PURPOSE: To present a survival analysis of 133 consecutively placed moderately rough implants, all with a total follow-up of 20 years.

MATERIALS AND METHODS: A total of 133 implants of the same brand placed in 46 patients at the same county clinic in Sweden were followed up prospectively over 20 years and analyzed for survival and bone height, the latter evaluated in periapical radiographs.

RESULTS: A total of 7 implants failed, 4 of which were in the same patient. Implant failure was associated with a combination of smoking and bruxism in 5 of the 7 failed cases. A 20-year survival rate of 94.7% was observed. Average marginal bone loss (MBL) at 20 years of follow-up was 0.543 ± 1.193 mm, with 9 implants having more than 2 mm of MBL. A total of 20 patients with 25 implants dropped out of the study; however, if death of the patient is excluded as a dropout reason, only 3 implants in 3 patients were unaccounted for.

CONCLUSIONS: Good clinical results in the 95% survival range were observed with moderately rough implants over a 20-year follow-up period.

Background: Overload from bruxism may affect survival of dental implants.

Objectives: To evaluate implant failure and marginal bone loss (MBL) in patients presenting with probable bruxism compared to non-bruxers. The study was registered in PROSPERO (CRD42021238397).

Methods: An electronic search September 2022 in PubMed/Medline, Web of Science and Science Direct was combined with a hand search. Two independent reviewers carried out abstract screening, full-text assessment, quality assessment (National Institutes of Health tool) and data extraction. Only studies that provided information on self-report and clinical examination needed for the diagnosis of at least 'probable' bruxism were included. A pairwise random-effect meta-analysis was carried out.

Results: In total 1338 studies were identified, and after screening and full-text assessment 27 studies that presented data on 2105 implants in probable bruxers and 10 264 implants in non-bruxers were included, with 138 and 352 implant failures in respective groups. the meta-analysis showed that implants placed in probable bruxers had a higher risk of failure than in non-bruxers (OR 2.189; 95% CI 1.337, 3.583, p = .002). A meta-regression showed that follow-up time did not affect this OR. Eighteen studies provided general data on MBL but did not report results separated between bruxers and non-bruxers. Therefore, an analysis of MBL was not possible.

Conclusion: The results of the present systematic review show that implants placed in probable bruxers present a significantly higher risk of failure than implants placed in non-bruxers. This should be considered in treatment planning and management of implant patients.

The aim of the present systematic review was to investigate the clinical outcomes after the perforation of the maxillary sinus by dental implants, or after maxillary sinus membrane perforation during sinus lift procedure. Twenty-nine publications were included. Failure rates of implants in cases where perforation of sinus floor had happened (11 studies) was generally low, and only one case of transient sinusitis was reported. The estimated failure rate of these implants was 2.1% (SE 1.0%, p = 0.035). There were 1817 implants (73 failures) placed in augmented sinuses in which the sinus membrane was perforated and 5043 implants (274 failures) placed in sinuses with no perforated membrane, from 18 studies. The odds of implant failure difference between the groups were not significant (OR 1.347, p = 0.197). log OR of implant failure between perforated and non-perforated membrane groups did not significantly change with the follow-up time (-0.004/month; p = 0.500). In conclusion, implant failure rate is generally low either for implants penetrating in the floor of the maxillary sinus or implants placed in augmented sinuses in which the sinus membrane was perforated. The prevalence of postoperative infection/sinusitis is low, and it may depend either on the dimensions of the perforation or on the anatomical predisposition.

Background: This study aimed to assess the survival of implants placed in the maxillary tuberosity or in the pterygomaxillary region of the maxilla, based on a systematic review of the literature. Methods: An electronic search was undertaken in three databases. The cumulative survival rate (CSR) was calculated. The log-rank (Mantel-Cox) test was used to compare the survival distributions between some groups. Results: Thirty-eight studies were included, reporting 3446 implants (3053 pterygoid, 393 tuberosity) in 2245 patients, followed up for a mean ± SD of 61.0 ± 36.3 months (min-max, 1-144). A total of 208 pterygoid and 12 tuber implants failed, with a clear concentration of failures in the first year of follow-up and a 10-year CSR of 92.5% and 96.9%, respectively. The survival of pterygoid implants was lower than that of implants in the maxillary tuberosity (p = 0.006; log-rank test), and the survival of implants submitted to early/delayed loading was lower than that of immediately loaded implants (p < 0.001; log-rank test). Non-splinted implants presented higher failure rates. Few cases of intra- or postoperative complications were reported. Conclusions: Implants placed in the pterygoid process/maxillary tuberosity present a high 10-year CSR, although with lower survival for pterygoid in comparison to tuber implants. Pterygoid/tuber implants that are splinted with other implants may present higher survival rates than those that are not splinted.

PURPOSE: The aim of the present systematic review was to investigate the influence of hypertension on the dental implant failure rate.

METHODS: An electronic search was undertaken in four databases, plus a manual search of journals. The I² statistic was used to check heterogeneity and the inverse-variance method was used for the meta-analysis. The estimate of relative effect for dichotomous outcome was expressed as an odds ratio (OR).

RESULTS: The review included 24 publications. There were 4874 implants (257 failures) placed in hypertensive patients and 16,192 implants (809 failures) placed in normotensive patients. A pairwise meta-analysis showed that implants in hypertensive patients did not have a higher risk of failure than implants placed in normotensive patients (OR 1.100, p = 0.671). The log OR of implant failure between hypertensive and normotensive patients did not significantly change with the follow-up time (p = 0.824).

CONCLUSIONS: This review suggests that implants in hypertensive patients do not present higher odds of failure in comparison to normotensive patients. However, further research on this topic, with the use of more rigorous criteria to diagnose patients as being hypertensive, as well as clearer information about the pharmacological management of the condition in the patients, is recommended.

Background: The placement of implants into the alveolar socket right after tooth extraction is called immediate implant placement (IIP). This approach has its particularities depending on which region of the jaws is involved. The anterior mandible region is peculiar due to the presence of mandibular incisors, which have the shortest roots among all permanent teeth.

Purpose: This study aimed to investigate the factors that could be associated with the risk of either cortical bone wall perforation or invasion of the 2 mm secure distance from the surrounding anatomical structures (defined as unsafe implant placement), with IIP in the maxillary aesthetic zone, in a cone-beam computed tomography (CBCT) virtual study.

Materials and methods: CBCT exams from 239 eligible subjects were investigated. Implants were virtually placed in two distinct positions: prosthetically-driven (along the long axis of the existing tooth) and bone-driven position (according to the available bone and with regard to nearby anatomical structures). Correlation between several variables was tested, and binary logistic regression analysis in order to assess of the possible associations between covariates and unsafe placement was performed.

Results: Safe placing implants was significantly higher for the bone-driven in comparison to the prosthetically-driven position (22.2% vs. 3.3%, respectively), and the 2-mm secure distance from anatomical structures was not possible to respect in the majority of cases (77.6% vs. 82.9%, respectively). Covariates associated with a higher risk of unsafe placement were tooth region (CI in relation to IL and CA), decrease of labial concavity angle (LCA), decrease of mandible basal bone height (MBBH), and decrease in mandibular bone thickness at the tooth apex level (MBT0).

Conclusion: The possibility of safely placing immediate implants in the anterior mandible is significantly higher for bone-driven than in prosthetically driven position. Presurgical virtual planning with CBCT is a great tool for minimizing the risk of implant unsafe placement with regards to the anatomical conditions in the mandible.

PURPOSE: This research aimed to investigate potential factors associated with the risk of perforation of the labial bone plate, nasal floor, or maxillary sinus floor during immediate implant placement (IIP) in the maxillary premolar area, utilizing a cone-beam computed tomography (CBCT) virtual study.

METHODS: CBCT exams from 179 eligible participants, encompassing 716 teeth, were included. Implants were virtually positioned in 2 orientations: along the long axis of the tooth (the prosthetically-driven position) and in an optimal position relative to adjacent anatomical structures (the bone-driven position). Binary logistic regression analysis was employed to assess potential associations between perforation or invasion and various covariates, including sex, age, tooth region, the distance from the tooth apex to the nasal floor or maxillary sinus floor, the angle between the prosthetically- and bone-driven positions (implant-line A angle [ILAA]), and the labial concavity angle (LCA).

RESULTS: The mean ILAA was 18.3°±8.0°, and the angle was significantly larger for the second premolar compared to the first premolar. The mean minimum implant length was 13.0±2.1 mm, with a bone anchorage of 4 mm. The incidence of perforation was 84.1% for the prosthetically-driven position and 40.5% for the bone-driven position. Factors associated with a higher risk of cortical bone wall perforation or invasion of the 2-mm safety margin from surrounding anatomical structures (in the bone-driven position) included female sex, older age, shorter distance from the tooth apex to the nasal cavity/maxillary sinus, and smaller LCA.

CONCLUSIONS: A high prevalence of cortical bone wall perforation or invasion of the 2-mm safety margin is anticipated when performing IIP in the maxillary premolar region.

BackgroundPyodermatitis-pyostomatitis vegetans (PPV) is a rare mucocutaneous disease characterized by multiple pustules and it is considered a marker for inflammatory bowel disease (IBD). The oral manifestations of this condition are referred to as pyostomatitis vegetans (PSV).PurposeTo investigate which features could help in establishing the diagnosis of PSV, with or without cutaneous lesions, based on information retrieved from all cases of PSV described in the literature. A case of PV from the authors was also included in the analysis.MethodsAn electronic search was undertaken, last updated in August 2022. Inclusion criteria included publications reporting cases of PSV, with the diagnosis confirmed by the pathological examination of oral or skin lesions, and presence of IBD.Results/ConclusionsSixty-two publications with 77 cases of PSV and an associated IBD were included. Features that are helpful in establishing the diagnosis of PSV are snail track appearance of oral lesions, an associated IBD (which is not always symptomatic), evidence of intraepithelial clefting on microscopic examination of oral lesions, and peripheral blood eosinophilia. A gold standard for the management of PSV does not exist and high-level evidence is limited. There is no established therapeutic protocol for PSV and management primarily consists of topical and/or systemic corticosteroids, antirheumatic drugs (sulfasalazine, mesalazine), monoclonal antibody (infliximab, adalimumab) immunosuppressives (azathioprine, methotrexate), antibiotics (dapsone), or a combination of these. The risk of recurrence of oral lesions is considerable when the medication dose is decreased or fully interrupted.

Background: Together with psychosocial and hereditary factors, bruxism is a pos-sible risk factor for orofacial pain. Bruxism is defined as a masticatory muscle activity characterized by repetitive or sustained tooth contact, or by bracing or thrusting of the mandible. A smartphone application to report awake bruxism (AB) has been de-veloped and translated into more than 25 languages.Objective(s): To translate the application into Swedish, adapt it to Swedish culture and conduct a study to evaluate the usability of the application for studies on family history and associated risk factors.Methods: Translation and cultural adaption of the Swedish version of the application (BruxApp) was carried out in a four-step sequential process. Ten young adults (22– 30 years) were recruited together with ten parents (42–67 years) and reported their AB with the application over two seven-day periods. Pain, stress and parafunctional behaviours were assessed by questionnaires.Results: The back translation check showed minimal discrepancies between the trans-lation and the English version. Participants did not report any problems with the ap-plication. Response rates for both groups were 65%. A difference in frequency of AB was shown between young adults and parents (22.0% vs. 12.5%, p< .001). A positive moderate correlation was found between AB and stress (r= 0.54, p= .017).Conclusion: The use of application strategies enables data collection on AB which can be used in both clinical and research settings. The results suggest that the Swedish version is ready for implementation and for studies on the relationships between AB, family history and psychosocial factors.

PURPOSE: To evaluate the survival rate of full-coverage tooth-supported fixed prosthetic restorations, single crowns (SCs), and fixed dental prostheses (FDPs), taking into consideration the potential influence of tooth-vitality, presence and type of post, and type of prosthetic restoration material.

MATERIALS AND METHODS: In October 2022, two authors independently conducted a search in PubMed, Web of Science, and Scopus electronic databases as well as a hand search to identify clinical human studies on full-coverage SCs and FDPs supported by vital and/or non-vital abutments and/or a combination of both, with a minimum observation period of 24 months.

RESULTS: Out of 4198 studies identified through the database search and 22 through hand searching, 26 studies fulfilled the inclusion criteria and were included in the analysis of the present systematic review. Included studies scored six points and more according to Newcastle-Ottawa Scale (NOS). The highest estimated 5-year survival rate was observed for (metal-ceramic and all-ceramic) SCs on vital teeth (98.3%; 95% CI [98.1, 98.6%]) and all ceramic SCs on non-vital teeth with fiber post (95.0%; 95% CI [94.5-95.4%]). Metal-ceramic SCs on vital teeth (97.1%; 95% CI [95.6-98.7%]) showed a statistically significant higher estimated 5-year survival rate compared to metal-ceramic SCs with cast metal post (90.7%; 95% CI [87.4-94.0%], P < 0.001), fiber post (91.3%; 95% CI [90.9-91.6%], P < 0.001) and without post (85.7%; 95% CI [80.7, 90.6%], P < 0.032). All-ceramic SCs with fiber post had a statistically significant higher estimated 5-year survival rate (95.0%; 95% CI [94.5-95.4%]) compared to metal-ceramic SCs on non-vital teeth with fiber post (91.3%; 95% CI [90.9-91.6%], P < 0.001). SCs (all-ceramic and metal-ceramic) with fiber post had a statistically significantly higher estimated 5-year survival rate of (92.7%; 95% CI [92.4-92.9%]) than SCs made of metal-ceramic and retained by cast metal post (90.7%; 95% CI [87.4-94.0%], P < 0.001). For FDPs, the 5-year survival rate was significantly higher for FDPs on vital abutments (84.9%; 95% CI [75.9, 93.9%]) compared to FDPs retained by non-vital abutment/s (81.3%; 95% CI [80.3, 82.2%], P = 0.049) irrespective to presence, type of post, and FDPs material. The results are limited by the limited number of studies and the presence of uncontrolled confounding clinical variables.

CONCLUSIONS: Within the limitations of the study, tooth vitality is suggested to contribute positively to the survival of SCs and FDPs.

The purpose of the present systematic review was to investigate the influence of bisphosphonates (BPs) on the dental implant failure rate and marginal bone loss (MBL). An electronic search was undertaken in three databases, plus a manual search of journals. Meta-analyses were performed, besides a meta-regression in order to verify how the log odds ratio (OR) was associated with follow-up time. The five- and ten-year estimated implant survivals were calculated. The review included 33 publications. Altogether, there were 1727 and 21,986 implants placed in patients taking and not taking BPs, respectively. A pairwise meta-analysis (26 studies) showed that implants in BP patients had a higher failure risk in comparison to non-BP patients (OR 1.653, p = 0.047). There was an estimated decrease of 0.004 in log OR for every additional month of follow-up, although it was not significant (p = 0.259). The global estimated implant survival in patients taking BPs after 5 and 10 years was 94.2% (95% CI, 94.0-94.4) and 90.1% (95% CI, 89.8-90.3), respectively. It was not possible to make any reliable analysis concerning MBL, as only two studies reported MBL results separated by groups. There is a 65.3% higher risk of implant failure in patients taking BPs in comparison to patients not taking this class of drugs.

PURPOSE: To compare the failure rates and the prevalence of technical complications between full-coverage tooth-supported monolithic zirconia (MZ) and porcelain-veneered zirconia (PVZ) fixed dental prosthesis, based on a systematic literature review.

METHODS: An electronic search was performed in three databases, supplemented by hand searching. Several statistical methods were used.

RESULTS: Seventy-four publications reported 6370 restorations (4264 PVZ; 2106 MZ; 8200 abutment teeth; 3549 patients), followed up until 152 months. A total of 216 prostheses failed, and survival was statistically significant different between groups. PVZ had higher occurrence of complications than MZ; the difference was especially greater for either minor or major chipping. The difference in prevalence of either minor or major chipping was statistically significant for PVZ prostheses between cementation with glass ionomer and adhesive resin cement (higher), adhesive resin and resin-modified glass ionomer cement (RMGIC, higher), and between RMGIC (higher) and glass ionomer cement. For MZ the difference was significant only for minor chipping between RMGIC (higher) and adhesive resin cement. Abutment teeth to PVZ prostheses more often lost vitality. Decementation was not observed with RMGIC. Air abrasion did not seem to clinically decrease the decementation risk. The 5-year difference in the occurrence of minor or major chipping between MZ and PVZ prostheses was statistically significant, but nor for catastrophic fracture.

CONCLUSION: Tooth-supported PVZ prostheses present higher failure and complication rates than MZ prosthesis. The difference in complications is striking when it comes to chipping.

CLINICAL RELEVANCE: Awareness of the outcome differences between different types of zirconia prostheses is important for clinical practice.

PURPOSE: To assess the clinical outcomes of zirconia dental implants based on an updated systematic literature review.

METHODS: An electronic search was performed in three databases, last updated in June 2023, supplemented by hand searching. The eligibility criteria were clinical studies reporting patients rehabilitated with zirconia implants. The cumulative survival rate (CSR) of implants was calculated. A meta-analysis for marginal bone loss (MBL) under different follow-up times and a meta-regression assessing the relationship between mean MBL and follow-up were done.

RESULTS: Twenty-five studies were included (4017 implants, 2083 patients). Seven studies had follow-up longer than 60 months. 172 implants failed, after a mean of 12.0 ± 16.1 months (min-max 0.3-86.0), of which 47 early failures, and 26 due to implant fracture, the majority in narrow-diameter implants. The 10-year CSR was 95.1%. Implants with coronal part prepared by drills presented statistically significant lower survival than non-prepared implants (p < 0.001). Two-piece implants presented lower survival than one-piece implants (p = 0.017). Implants discontinued from the market presented lower survival than the commercially available ones (p < 0.001). The difference in survival was not significant between implants in maxilla and mandible (p = 0.637). The mean MBL fluctuated between 0.632 and 2.060 mm over long periods of observation (up until 132 months). There was an estimated MBL increase of 0.005 mm per additional month of follow-up.

CONCLUSION: Zirconia implants present high 10-year CSR and short-term low MBL. The review was registered in PROSPERO (CRD42022342055).

CLINICAL RELEVANCE: The clinical outcomes observed for zirconia dental implants are very promising, although these have not yet been extensively studied as titanium alloy implants.

PURPOSE: To investigate the influence of cantilever prosthetic arm on the marginal bone loss (MBL) over time around dental implants supporting short fixed partial dentures (FPDs), in a record-based retrospective study.

METHODS: All cases of 3-unit implant-supported FPDs, supported by 2-3 implants, from the database of cases treated at one specialist clinic were considered for inclusion. Only implants with a minimum of 36 months of radiological follow-up were considered. Univariate linear regression models were used to compare MBL over time between 12 clinical covariates, after which a linear mixed-effects model was built.

RESULTS: One-hundred-thirty-nine patients (64 men, 75 women) with 164 3-unit implant-supported FPDs (333 implants supporting non-cantilevered FPDs, 94 supporting cantilevered FPDs) were included in the study. The patients were followed up clinically and radiographically for a mean of 154.1 ± 78.0 (min-max, 37.3-364.6) and 132.9 ± 77.3 months (min-max, 36.8-329.9), respectively. The total number of marginal bone level double measurements (mesial and distal sides of each implant) was 2909. FPDs with cantilever presented an estimated greater MBL over time compared to FPDs without cantilever. Bruxism, sex (women), implant (modified) surface, and (poor) bone quality were also associated with higher MBL over time.

CONCLUSIONS: The use of a cantilever extension is suggested to negatively affect the bone marginal level over time around implants supporting 3-unit FPDs. Due to the small difference of the estimated MBL over long periods of follow-up between the groups, it is a matter of debate if the observed negative effect may be of clinical significance.

This dental record-based retrospective study aimed to compare the marginal bone loss (MBL) around dental implants in a group of smokers in relation to a matched group of non-smokers, with a special focus on five different frequencies of daily smoking (non-smokers, and frequency of 1-5, 6-10, 11-15, and 20 cig./day). Only implants with a minimum of 36 months of radiological follow-up were considered. Univariate linear regression models were used to compare MBL over time between 12 clinical covariates, after which a linear mixed-effects model was built. After matching of the patients, the study included 340 implants in 104 smokers, and 337 implants in 100 non-smokers. The results suggested that smoking degree (greater MBL for higher degrees of smoking), bruxism (greater MBL for bruxers), jaw (greater MBL in maxilla), prosthesis fixation (greater MBL for screw-retained prosthesis), and implant diameter (greater MBL for 3.75-4.10 mm) had a significant influence on MBL over time. There appears to be a positive correlation between the degree of smoking and the degree of MBL, meaning, the higher the degree of smoking, the greater the MBL. However, the difference is not apparent for different degrees of smoking when this is high, namely above 10 cigarettes per day.

The aim of this present record-based retrospective study was to investigate the influence of the crown-implant ratio (CIR) and implant inclination in relation to the occlusal plane on the marginal bone loss (MBL) around dental implants supporting single crowns in the posterior region of the jaws. All the cases of implant-supported single crowns in the premolar and molar regions were initially considered for inclusion. Only implants not lost, with baseline radiographs taken within 12 months after implant placement and with a minimum of 36 months of radiological follow-up, were considered for the analysis of MBL. Univariate linear regression models were used to compare MBL over time between 12 clinical covariates, after which a linear mixed-effects model was built. After the exclusion of 49 cases, a total of 316 implant-supported single crowns in 234 patients were included. The results from the statistical models suggested that implant inclination and anatomical- and clinical CIR (the main related factors investigated in the study) were not statistically significantly related to MBL over time. Age (older people), tooth region (premolar), and bruxism (bruxers) had a statistically significant influence on MBL over time.

PURPOSE: To assess the influence of several factors on the survival of tooth-supported fixed partial dentures (FPDs) with vital and non-vital abutments.

MATERIALS AND METHODS: The present retrospective cohort study was based on the records of patients treated with 3-to-7-unit tooth-supported FPDs with a minimum follow-up time of 6 months after prosthesis delivery. Cumulative survival rate (CSR) was calculated over the maximum follow-up period. Cox regression models were used to evaluate the association between the clinical covariates and prosthesis failure.

RESULTS: A total of 331 FPDs in 229 patients were included. The CSRs were 90.1% and 77.6% after 5 and 10 years and 67.9% and 52.1% after 15 and 20 years, respectively. Tooth-supported FPD failure was more prevalent within the first years of prosthesis delivery. Loss of one or more abutment teeth and loss of prosthesis retention were the main reasons for failure. Smoking and type of prosthesis material significantly influenced the survival of FPDs. Abutment vitality, position of the non-vital abutment, or prosthesis length did not show any significant influence on the occurrence of prosthesis failure.

CONCLUSION: Smoking and the type of prosthesis material are suggested to contribute to an increased rate of FPD failure irrespective of abutment vitality.

ObjectivesThe aim of the present retrospective study was to compare the marginal bone loss (MBL) around dental implants in a group of diabetic patients in relation to a matched group of non-diabetic patients.Materials and methodsThe present dental record-based retrospective study included patients selected from individuals treated with dental implants at one specialist clinic in Malmo, Sweden. Patients were excluded if they had history of periodontitis and/or were treated for periodontal disease. The study group included 710 implants installed in 180 patients (mean age 60.3 +/- 13.0 years), 349 implants in 90 diabetic (21 T1DM and 69 T2DM patients), and 361 implants in 90 non-diabetic patients.ResultsThe results suggested that jaw (greater MBL in the maxilla), diabetes (greater MBL for diabetic patients, and worse for T1DM patients), bruxism (greater MBL for bruxers), and smoking (greater MBL for smokers and former smokers) had a statistically significant influence on MBL over time.ConclusionsPatients with diabetes have an estimated greater MBL over time compared to non-diabetic patients. The difference was greater in patients with diabetes type 1 compared to patients with diabetes type 2. Bruxism, smoking, and implant location (maxilla) were also associated with a higher loss of marginal bone around implants over time.

PURPOSE: To compare marginal bone loss (MBL) around dental implants in a group of bruxers in relation to a matched group of non-bruxers.

METHODS: The present record-based retrospective study included patients selected from individuals treated with dental implants at one specialist clinic in Malmö. Only implants not lost and with baseline radiographs taken within 12 months after implant placement and with a minimum of 36 months of radiological follow-up were considered for inclusion. Univariate linear regression models and a linear mixed-effects model were performed.

RESULTS: Two hundred and four patients (104 bruxers, 100 non-bruxers), with a total of 811 implants (416 in bruxers, 395 in non-bruxers) were included in the study. The results of the linear mixed-effects model suggested that bruxism, smoking, age, region of the jaws, implant diameter, and prosthesis type had a statistically significant influence on MBL over time. Individuals who are both bruxers and smokers showed greater MBL when compared to individuals who are either a bruxer or smoker, or neither (p < 0.001).

CONCLUSIONS: Bruxism is suggested to increase the risk of MBL over time, as well as higher age, smoking, and the combination of bruxism and smoking. Other factors that showed a correlation with increased MBL were implant diameter, region of the jaws, and prosthesis type, but it is not possible to draw robust conclusions for these factors, as the categories of these variables were very unbalanced.

Background and Objectives: Implant-supported single crowns have become a routine approach for the replacement of missing single teeth, being considered as one of the most common ways of rehabilitation when adjacent teeth are healthy. The present retrospective study aimed to investigate the risk factors possibly associated with failure and technical complications of implant-supported single crowns and their supporting implants. Materials and Methods: Patients treated at one faculty (2009-2019) were considered for inclusion. Complications investigated included ceramic fracture/chipping, crown loss of retention/mobility, crown failure/fracture, loosening/loss/fracture of prosthetic screw, and implant failure/fracture. Any condition/situation that led to the removal/replacement of crowns (implant failure not included) was considered prosthesis failure. Univariate/multivariate Cox regression models were used to evaluate the associations between clinical covariates and failure. Results: 278 patients (358 crowns) were included. Mean & PLUSMN; SD follow-up was 56.5 & PLUSMN; 29.7 months. Seven implants (after a mean of 76.5 & PLUSMN; 43.7 months) and twenty crowns (21.3 & PLUSMN; 23.5 months) failed. The cumulative survival rate (CSR) for crowns was 93.5% after 5, remaining at 92.2% between 6 and 11 years. The most common reasons for crown failure were porcelain large fracture (n = 6), crown repeatedly loose (n = 6), and porcelain chipping (n = 5). Men and probable bruxism were identified in the Cox regression model as being associated with crown failure. The most common observed technical complications were mobility of the crown and chipping of the ceramic material, with the latter being observed even in crowns manufactured of monolithic zirconia. Cases with at least one technical complication (not considering loss of screw hole sealing) were more common among probable bruxers than in non-bruxers (p = 0.002). Cases of ceramic chipping were more common among bruxers than in non-bruxers (p = 0.014, log-rank test). Conclusions: Probable bruxism and patient's sex (men) were factors associated with a higher risk of failure of implant-supported single crowns.

Aim: To evaluate the accuracy of tridimensional (3D)-printed guide-assisted flapless cortical bone micro-osteoperforations (MOPs) in the anterior mandible on a cadaver model. Materials and methods: Five human cadaver heads with complete dentition in the anterior mandible were used in the present study. Preplanning CBCT and intraoral surface scans were obtained. After alignment, drilling sites in the interradic-ular areas were planned from canine to canine, and a surgical guide was printed. The drilling was performed and a post -procedure CBCT scan was obtained to assess the accuracy of the procedure in relation to the virtual planning. Results: The mean +/- standard deviation (SD) mesiodistal interradicular space was 2.67 +/- 0.84 mm. The mean +/- SD error of the actual drilled hole compared with the planned position of the mesial drill site was 0.66 +/- 0.33 mm, and to the distal drill site it was 0.56 +/- 0.33 mm. There was a statistically signifi-cant difference between the number of times the teeth were hit mesially (10 out of 64 holes) and distally (none). Conclusions: The proposed technique, limited to an ex vivo scenario, provides a valid and reliable method for mandibu-lar MOPs using a 3D-generated surgical guide. However, the risk of damaging adjacent radicular surfaces, particularly in areas with limited mesiodistal interradicular bone, needs to be considered. Further studies should focus on using thinner drills and adding other methods to stabilize the guide. Addi-tionally, by selecting individuals and perforation sites with more mesiodistal interradicular bone, less damage is likely.

Objectives/aim To analyze and compare costs of different prosthetic rehabilitations for the edentulous maxilla. Materials and methods Patients with edentulous maxillae were rehabilitated with either of three implant-supported prosthetic protocols; removable overdenture supported by 2 implants (ISOD 2), fixed dental prostheses supported by 4 (ISFAFDP 4) or 6 (ISFAFDP 6) implants. Cost of treatment and costs during follow-up were registered and compared. Results Twenty-four patients were included: six patients received ISOD 2 treatment, eight patients received ISFADP 4 treatment and ten patients received ISFADP 6 treatment. Initial costs for ISFAFDP 6 were higher than costs for ISFAFDP 4 and ISOD 2, but there were no differences in cost for maintenance i.e., the ISOD treatment remained the least costly treatment alternative after 1-year follow-up. Discussion The lack of difference in cost for maintenance and repair over the first year suggests that implant-supported overdentures will remain the least costly treatment option for the edentulous maxilla, at least in a short-term perspective. Conclusions Removable maxillary overdentures supported by 2 implants may be a valid low cost treatment option.

PURPOSE: To investigate and compare the demographic data, occurrence of recurrence and metastasis, and survival prognosis between ameloblastic carcinoma and metastasizing ameloblastoma, based on appropriate and currently accepted eligible diagnostic criteria, in a systematic review of the literature.

METHODS: An electronic search was undertaken, last updated in December 2021. Eligibility criteria included publications having enough clinicopathological information to confirm the diagnosis of these tumors.

RESULTS: Seventy-seven publications reporting 85 ameloblastic carcinomas and 43 metastasizing ameloblastomas were included. Both tumors were more frequent in mandible and showed different clinical profiles regarding patients' sex and age. There was no difference in the estimated cumulative survival between patients diagnosed with these tumors. Metastases mainly affected the lungs, followed by cervical lymph nodes. The mean time between the first metastasis and the last follow-up was higher for metastasizing ameloblastoma (p=0.021). Additionally, metastasizing ameloblastoma patients remained alive longer than ameloblastic carcinoma patients after the first metastasis diagnosis (p=0.041). Considering only the cases that metastasized, a higher ratio of ameloblastic carcinoma patients died in comparison to metastasizing ameloblastoma patients (p=0.003). The occurrence of recurrence was associated with a conservative primary treatment with both ameloblastic carcinoma (p<0.001) and metastasizing ameloblastoma tumors (p=0.017). Multiple recurrent events were associated with conservative primary therapies with metastasizing ameloblastoma (p<0.001) but not with ameloblastic carcinoma (p=0.121).

CONCLUSIONS: In addition to some demographic differences, ameloblastic carcinomas that metastasize present a worse prognosis than metastasizing ameloblastoma. As conservative procedures are associated with multiple recurrent events, this treatment modality should be avoided for both tumors. This article is protected by copyright. All rights reserved.

The present review aimed to evaluate the impact of diabetes mellitus on dental implant failure rates and marginal bone loss (MBL). An electronic search was undertaken in three databases, plus a manual search of journals. Meta-analyses were performed as well as meta-regressions in order to verify how the odds ratio (OR) and MBL were associated with follow-up time. The review included 89 publications. Altogether, there were 5510 and 62,780 implants placed in diabetic and non-diabetic patients, respectively. Pairwise meta-analysis showed that implants in diabetic patients had a higher failure risk in comparison to non-diabetic patients (OR 1.777, p < 0.001). Implant failures were more likely to occur in type 1 diabetes patients than in type 2 (OR 4.477, p = 0.032). The difference in implant failure between the groups was statistically significant in the maxilla but not in the mandible. The MBL mean difference (MD) between the groups was 0.776 mm (p = 0.027), with an estimated increase of 0.032 mm in the MBL MD between groups for every additional month of follow-up (p < 0.001). There was an estimated decrease of 0.007 in OR for every additional month of follow-up (p = 0.048). In conclusion, implants in diabetic patients showed a 77.7% higher risk of failure than in non-diabetic patients.

OBJECTIVES: Acute as well as chronic pain syndromes are common after whiplash trauma and exercise therapy is proposed as one possible intervention strategy. The aim of the present systematic review was to evaluate the effect of exercise therapy in patients with Whiplash-Associated Disorders for the improvement of neck pain and neck disability, compared with other therapeutic interventions, placebo interventions, no treatment, or waiting list.

CONTENT: The review was registered in Prospero (CRD42017060356) and conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A literature search in PubMed, Scopus and Cochrane from inception until January 13, 2020 was combined with a hand search to identify eligible randomized controlled studies. Abstract screening, full text assessment and risk of bias assessment (Cochrane RoB 2.0) were conducted by two independent reviewers.

SUMMARY: The search identified 4,103 articles. After removal of duplicates, screening of 2,921 abstracts and full text assessment of 100 articles, 27 articles that reported data for 2,127 patients were included. The included articles evaluated the effect of exercise therapy on neck pain, neck disability or other outcome measures and indicated some positive effects from exercise, but many studies lacked control groups not receiving active treatment. Studies on exercise that could be included in the random-effect meta-analysis showed significant short-term effects on neck pain and medium-term effects on neck disability.

OUTLOOK: Despite a large number of articles published in the area of exercise therapy and Whiplash-Associated Disorders, the current evidence base is weak. The results from the present review with meta-analysis suggests that exercise therapy may provide additional effect for improvement of neck pain and disability in patients with Whiplash-Associated Disorders.

The purpose of the study was to investigate the influence of multiple factors on the survival of tooth-supported single crowns and assess the biological and technical complications. This retrospective study included patients rehabilitated with single crowns with a minimum follow-up time of 6 months after delivery. The cumulative survival rate was calculated over the maximum period of follow-up time and reported in a life-table survival analysis. Univariate and multivariate Cox regression was used to evaluate the associations between clinical covariates and crown failure. The included cohort group consisted of 1037 single crowns delivered in 401 patients and followed for a mean of 134.8 ± 80.2 months. Cumulative survival rate was 89.9% and 80.9% after 5 and 10 years and 70.5% and 61.8% after 15 and 20 years, respectively. The main reasons for single crown failure were loss of retention, tooth loss, and fracture. Anterior placement, non-vital abutments, and bruxism significantly influenced the survival of single crowns. The survival of single crowns was not influenced by patient's age and sex, location of the crowns in relation to the jaws, type of tooth, presence of post and core, and type of crown material, treatment providers, or smoking. Anterior placement, non-vital abutments, and bruxism are factors suggested to increase the risk of single crown failure and the prevalence of technical and biological complications.

Background: Tooth-supported fixed dental prosthesis (FDP) is one of the most reliable treatment options to replace missing teeth. The longevity of the treatment could, however, be affected by several general and local factors, especially bruxism.

Objective: To investigate the influence of bruxism on the long-term survival of tooth-supported FDPs in bruxers compared to a matched group of nonbruxers, taking several clinical variables into account.

Materials and methods: The present retrospective cohort study was based on records of patients treated with 3-7-unit tooth-supported FDPs with a minimum follow-up time of 6 months after prosthesis delivery. The criteria for the diagnosis of "possible" and "probable" sleep or awake bruxism were used. A matched group of nonbruxers was selected on the basis of similarities in four factors, patients' gender and age, number of prosthetic units of the FDPs, and follow-up time. The paired-samples t-test or Wilcoxon signed rank test were used to compared mean values between the two groups. Contingency tables of categorical data were analyzed by McNemar's test.

Results: The cohort group consisted of 62 noncantilevered FDPs in each group, followed up for a mean of 110.1 and 106.5 months (bruxers and nonbruxers, respectively). Tooth-supported FDPs in bruxers presented significantly higher failure rate than in nonbruxers (32.3% vs. 25.8%, respectively; p = 0.001). Loss of retention and tooth loss were the main reasons for failures in both groups. For nonsmokers, the FDP failure rate was higher in nonbruxers. Technical and biological complications were significantly more prevalent in bruxers compared to nonbruxers.

Conclusions: Bruxism is suggested to increase technical and biological complications and FDP failure.

Purpose: To investigate the risk factors related to failure of removable partial dentures (RPDs) and to compare the survival of RPDs when abutment teeth have good vs reduced bone support. Materials and Methods: In this longitudinal patient record-based cohort study with a mean follow-up of 44.9 months, Cox regression models were used to evaluate the associations between clinical covariates and abutment tooth failure, as well as prosthesis failure. Results: A total of 142 patients and 172 RPDs were included. Of the 172 prostheses, 64 (nearly 40%) failed after a mean time of about 4 years. Loss of abutment teeth was the main reason leading to RPD failure, followed closely by poor fit and adaptation. No factor was shown to be statistically significant at the prosthesis level. Women (Hazard Ratio [HR] = 0.542), endodontic treatment (HR = 3.460), presence of post and core (HR = 0.302), presence of a prosthetic crown (HR = 3.403), and abutment tooth type (in relation to incisor: canine HR = 0.196, premolar HR = 0.449) were the risk factors statistically significantly associated with the loss of abutment teeth. The pre-prosthesis amount of bone support of the teeth did not affect their prognosis as abutments for RPDs. Conclusion: RPD treatment modality presented a high failure rate after a mean follow-up of 4 years. Vital abutment teeth had a better survival rate than the ones treated endodontically (whether restored with or without a post and core); nevertheless, the amount of bone support did not affect their survival.

Background and Objectives: Tobacco is today the single most preventable cause of death, being associated with countless diseases, including cancer and neurological, cardiovascular, and respiratory diseases. Smoking also brings negative consequences to oral health, potentially impairing treatment with dental implants. The present review aimed to evaluate the influence of smoking on dental implant failure rates and marginal bone loss (MBL). Materials and Methods: Electronic search was undertaken in three databases, plus a manual search of journals. Meta-analyses were performed, in addition to meta-regressions, in order to verify how the odds ratio (OR) and MBL were associated with follow-up time. Results: The review included 292 publications. Altogether, there were 35,511 and 114,597 implants placed in smokers and in non-smokers, respectively. Pairwise meta-analysis showed that implants in smokers had a higher failure risk in comparison with non-smokers (OR 2.402, p < 0.001). The difference in implant failure between the groups was statistically significant in the maxilla (OR 2.910, p < 0.001), as well as in the mandible (OR 2.866, p < 0.001). The MBL mean difference (MD) between the groups was 0.580 mm (p < 0.001). There was an estimated decrease of 0.001 in OR (p = 0.566) and increase of 0.004 mm (p = 0.279) in the MBL MD between groups for every additional month of follow-up, although without statistical significance. Therefore, there was no clear influence of the follow-up on the effect size (OR) and on MBL MD between groups. Conclusions: Implants placed in smokers present a 140.2% higher risk of failure than implants placed in non-smokers.

The aim of this prospective randomized clinical study was to compare the clinical treatment outcome for single dental implants submitted to either immediate loading (IL) or delayed loading (DL) after 5 years of follow-up. Fifty patients with a missing maxillary tooth (15-25) were randomly allocated to either the IL or DL. The treatment procedures included implant installation in healed sites, temporary screw-retained crown and replacement with a permanent single implant crown. The two groups were evaluated with regard to implant survival, marginal bone level, papillae index, pink and white esthetic score (PES, WES). At the 5-year follow-up the implant survival rate was 100% and 95.8% for IL and DL, respectively. Implant success rate was 91.7% and 83.3% for IL and DL, respectively. The mean +/- SD marginal bone loss for IL and DL was -0.50 +/- 0.73 mm and -0.54 +/- 0.65 mm, respectively. (p = 0.782). Statistically significant less marginal bone loss was found non-smokers (p = 0.021). No statistically significant differences were found for IL and DL concerning papillae index PES and WES after 5 years. This study suggests that implant-supported single crowns in the maxillary aesthetic zone can present similar results with respect to either IL or DL after 5 years.

Purpose

To evaluate the bond strength between polymer-based copings and zirconia copings as positive control, cemented on implant-supported titanium bases with different adhesive cement systems. Moreover, to evaluate if airborne-particle abrasion of polymethylmetacrylate (PMMA) would enhance the bond strength.

Methods

Four groups of different materials were used to fabricate the copings, 30 in each group: airborne-particle abraded milled zirconia (TAZirconia, control group), milled PMMA (TPMMA), airborne-particle abraded milled PMMA (TAPMMA) and 3 D-printed micro filled hybrid resin (TAMFH). Each group of copings was cemented on titanium bases by three different adhesive cement systems, 10 each: Multilink Hybrid Abutment, Panavia V5, RelyX Ultimate. The specimens were stored dry at room temperature for 24 h, subjected to thermocycling for 5000 cycles followed by evaluating the bond strength by tensile strength test.

Results

TPMMA and TAPMMA cemented with Multilink Hybrid Abutment showed statistically significant lower bond strength in comparison to TAZirconia and TAMFH. No difference was observed between the latter two. TPMMA, TAPMMA and TAMFH had a statistically significant lower bond strength compared to the control group when cemented with Panavia V5. TPMMA and TAPMMA cemented with Rely X Ultimate showed statistically significant lower bond strength in comparison to the control group.

Conclusion

Almost all experimental groups, except 3 D-printed MFH, performed inferior than the positive control group where the highest bond strength was reported for the cementation of zirconia copings cemented with Panavia V5 or Rely X Ultimate. Airborne-particle abrasion did not improve the bond strength of the PMMA, except when Multilink Hybrid Abutment was used.

The purpose of this review was to integrate the clinical, radiological, microscopic, and molecular data of published cherubism cases, in addition to therapeutic approaches, to provide more concise information about the disease. An electronic search was undertaken in September 2019. Eligibility criteria included publications having enough clinical, radiological, and histological information to confirm the diagnosis. A total of 260 publications reporting 513 cherubism cases were included. Familial history was observed in 310/458 cases (67.7%). SH3BP2 mutations were reported in 101/108 cases (93.5%) and mainly occurred at protein residues 415, 418, 419, and 420. Retrospective clinical grading was possible in 175 cases. Advanced clinical grading was associated with tooth agenesis, but not with other clinical, radiological, and genetic features. Specific amino acid substitutions of SH3BP2 mutations were not associated with the clinical grading of the disease. 'Wait and see' was the most common therapeutic approach. In a small number of cases, drugs were used in the treatment, with variable response. In conclusion, there is no clear correlation between the genotype and the phenotype of the disease, but additional genomic and gene expression regulation information is necessary for a better understanding of cherubism.

The present review aimed to evaluate the difference of dental implant failure rates and marginal bone loss (MBL) between implants inserted in fresh extraction sockets or healed sites. Electronic search was undertaken in three databases, plus manual search of journals, including studies randomized or not. Meta-analyses were performed besides meta-regressions, in order to verify how the odds ratio (OR) and MBL were associated with follow-up time. The review included 163 publications. Altogether, there were 17,278 and 38,738 implants placed in fresh extraction sockets and healed sites, respectively. Pairwise meta-analyses showed that implants in sockets had a higher failure risk in comparison to healed sites: OR 1.349, all studies included; OR 2.070, only prospective non-RCTs; OR 2.487, only RCTs (all p < 0.001). The difference in implant failure between the groups was statistically significant in the maxilla (OR 1.616, p = 0.029), but not in the mandible (OR 2.192, p = 0.075). The MBL mean difference (MD) between the groups was -0.053 mm (p = 0.089). There was an estimated decrease of 0.003 in OR (p = 0.284) and an increase of 0.006 mm (p = 0.036) in the MBL MD between groups for every additional month of follow-up. In conclusion, implants placed in fresh extraction sockets present higher risk of failure than implants placed in healed sites.

This study aimed to investigate the factors that could be associated with the risk of labial cortical bone wall perforation with immediate implant placement (IIP) in the maxillary aesthetic zone, in a cone-beam computed tomography (CBCT) virtual study. CBCT exams from 126 qualified subjects (756 teeth) were included. Implants were virtually positioned in two different positions: in the long axis of the tooth (prosthetically-driven position) and in an ideal position in relation to adjacent anatomical structures (bone-driven position). Two different implant diameters were planned for each tooth position, namely, 3.75 and 4.3 mm for central incisors and canines, and 3.0 and 3.3 mm for lateral incisors. The incidence of perforation was nearly 80% and 5% for prostheticallyand bone-driven position, respectively. Factors associated with a higher risk of cortical bone wall perforation (bone-driven position), according to logistic regression analysis, were women, wider implants, Sagittal Root Position class IV, and decrease of the labial concavity angle. Perforation of the labial cortical bone wall can be greatly minimized when the implant is placed in a bone-driven position compared to a prosthetically-driven position. It is important to preoperatively evaluate the morphological features of the implant site for risk assessment and to individualize the treatment plan. 

Purpose: To assess the clinical outcomes of maxillary overdentures supported by dental implants by conducting a literature review. Materials and Methods: An electronic search was undertaken in March 2019. Eligibility criteria included publications reporting cases of implant-supported maxillary overdentures with follow-up information. Results: A total of 131 publications were included (1,478 overdentures supported by 6,681 implants). The mean number of attachments per overdenture was 3.8 ± 1.2 (range: 1 to 9), and a bar-clip system was used in about half of the cases. The prostheses were followed up for a mean of 47.9 ± 32.8 (range: 1 to 240) months. A total of 401 implants (6.0%) failed in 219 patients (14.8%), and 55 prostheses (3.7%) failed at a mean of 40.2 ± 53.2 (range: 6 to 240) months after placement. Most of the failures happened within the first year after placement for both implants (52.1%) and prostheses (41.8%). Patients with fewer implants per prosthesis presented higher prosthesis failure rates than patients with more implants per prosthesis. The cumulative survival rate for dental implants after 19 years was 70.4%, and for implant-supported maxillary overdentures was 79.8%. Presence of palatal coverage and/or metallic structure/reinforcement does not seem to have an influence on failure rate. Of the most commonly used attachment systems, the ball/O-ring and the Ceka were the ones with the highest rates of patients having at least one implant failure. Conclusion: Most of the prosthesis failures were due to loss of implants, and the first year was the most critical period for failures. The number of dental implants placed per patient seemed to have an impact on the occurrence of overdenture failure.

The presented study aimed to assess the survival rate of porcelain laminate veneers (PLV) based on a systematic review of the literature. An electronic search was last updated in February 2021. Eligibility criteria included clinical series of patients rehabilitated with PLVs published in the last 25 years, with a minimum follow-up of 3 years. Survival analysis methods were applied. Twenty-five studies were included, with 6500 PLVs. The 10-year estimated cumulative survival rate (CSR) of PLVs was 95.5%. The 10-year CSR of PLVs when fracture, debonding, occurrence of secondary caries, and need of endodontic treatment were considered as isolated reasons for failure were 96.3%, 99.2%, 99.3%, and 99.0%, respectively. PLVs without incisal coverage had a higher failure rate than PLVs with incisal coverage. Non-feldspathic PLVs performed better than feldspathic PLVs. As a conclusion, the 10-year CSR of PLVs was 95.5%, when fracture, debonding, occurrence of secondary caries, and need of endodontic treatment were considered as reasons for restoration failure. Fracture seems to be most common complication of PLVs, followed by debonding, with both more commonly happening within the first years after PLV cementation. PLVs with incisal coverage and non-feldspathic PLVs presented lower failure rates than PLVs without incisal coverage and feldspathic PLVs.

OBJECTIVE:

The aim of the present study was to evaluate the accuracy of an extraoral CBCT-planned 3D-printed surgical guide aimed to percutaneous injection of substances into the temporomandibular joint (TMJ) and the lateral pterygoid muscle (LPM).

METHODS:

Nine human cadaver heads were used. Pre-planning CBCT and facial scans were obtained and three percutaneous injection sites were planned: one for the lower compartment of the TMJ and two for the LPM. A digital surgical guide was then designed with small titanium sleeves and printed by a 3D printer. After the injections, new CBCT scans with the needles in place were obtained in order to assess the accuracy of the procedure in relation to the virtual planning.

RESULTS:

The mean values for angle deviation were very low (range 1.13o-4.08o), the same happening for the mean difference in the length reached (range 1.82–2.64 mm), as well as for the mean difference in the needle tip dislocation (range 0.94–2.03 mm).

CONCLUSION:

The guide seems to be a reliable tool for accurate percutaneous injection of drugs into the inferior compartment of the TMJ and the LPM. Further studies are necessary to test the efficacy and validate the method in an in vivo study.

The present review aimed to evaluate the impact of implant length on failure rates between short (<10 mm) and long (>= 10 mm) dental implants. An electronic search was undertaken in three databases, as well as a manual search of journals. Implant failure was the outcome evaluated. Meta-analysis was performed in addition to a meta-regression in order to verify how the risk ratio (RR) was associated with the follow-up time. The review included 353 publications. Altogether, there were 25,490 short and 159,435 long implants. Pairwise meta-analysis showed that short implants had a higher failure risk than long implants (RR 2.437, p < 0.001). There was a decrease in the probability of implant failure with longer implants when implants of different length groups were compared. A sensitivity analysis, which plotted together only studies with follow-up times of 7 years or less, resulted in an estimated increase of 0.6 in RR for every additional month of follow-up. In conclusion, short implants showed a 2.5 times higher risk of failure than long implants. Implant failure is multifactorial, and the implant length is only one of the many factors contributing to the loss of an implant. A good treatment plan and the patient's general health should be taken into account when planning for an implant treatment.

The aim of this study was to evaluate the sensitivity, accuracy, and reliability of two-dimensional computed tomography (2D-CT) scans (axial, coronal, sagittal planes) and three-dimensional computed tomography (3D-CT) reconstructions in diagnosing midfacial fractures in relation to actual fractures identified clinically and during surgery (gold standard). The imaging diagnosis was performed by a radiologist and an oral and maxillofacial surgeon. Sixty-two patients with a total of 429 midfacial fractures were included. Frontal sinus and nose fractures were easily diagnosed. For the three CT planes, there was a statistically significant difference between the CT examination and the gold standard for five to seven of the nine bones evaluated, while for 3D-CT, a difference was observed only for fractures of the orbital floor. The inter-observer agreement between the oral and maxillofacial surgeon and the radiologist was 75.5%. In conclusion, in this study 3D-CT reconstructions showed significantly the best sensitivity, accuracy, and reliability for the diagnosis of midfacial fractures. The sagittal reconstructions were the least diagnostic of the 2D-CT images. For areas where the parameters studied showed less agreement and hence a more difficult diagnosis, we recommend a combination of 3D and 2D-CT images to improve diagnostic accuracy.

BACKGROUND: The oral rehabilitation with fixed restorations supported by the combination of teeth and dental implants has been advocated in some cases.

PURPOSE: To assess the clinical outcomes of these prostheses. Fixed restorations supported by the combination of teeth and dental implants.

MATERIALS AND METHODS: This retrospective study included all patients treated with combined tooth-implant-supported fixed dental prostheses (FDPs) at one specialist clinic. Abutment/prosthesis failure and technical complications were the outcomes analyzed.

RESULTS: A total of 85 patients with 96 prostheses were included, with a mean follow-up of 10.5 years. Twenty prostheses failed. The estimated cumulative survival rate was 90.7%, 84.8%, 69.9%, and 66.2% at 5, 10, 15, and 20 years, respectively. The failure of tooth and/or implant abutments in key positions affected the survival of the prostheses. There were seven reasons for prostheses failure, with the loss of abutments exerting a significant influence. Bruxism was possibly associated with failures. Prostheses with cantilevers did not show a statistically significant higher failure rate. No group had a general higher prevalence of technical complications in comparison to the other groups.

CONCLUSIONS: Although combined tooth-implant-supported FDPs are an alternative treatment option, this study has found that across 20 years of service nearly 35% the prostheses may fail.

Background and Objectives: To integrate the available published data on patients with oral lichen planus (OLP) rehabilitated with dental implants, as well as to review the recommendations for OLP patients receiving implants. Materials and Methods: An electronic search was undertaken in February 2019 using five databases. Publications reporting cases of patients with OLP and rehabilitated with implant-supported oral prosthesis were included. Results: Twenty-two publications were included (230 patients, 615 implants). The overall implant failure rate was 13.9% (85/610). In patients with oral squamous cell carcinoma (OSCC) the failure rate was 90.6% (29/32), but none of these implants lost osseointegration; instead, the implants were removed together with the tumor. One study presented a very high implant failure rate, 76.4% (42/55), in patients with “active lichen planus”, with all implants failing between 7–16 weeks after implant placement, and its conflicting and incongruent results are discussed in detail. There was a statistically significant difference between the failure rates in implants installed in different jaws (maxilla/mandible) and when implants of different surfaces were used (turned/moderately rough), but not between patients with reticular or erosive OLP types, or between male and female patients. If OSCC patients and the cases of the latter study are not considered, then the failure rate becomes very low (2.7%, 14/523). The time between implant placement and failure was 25.4 ± 32.6 months (range 1–112). The mean ± SD follow-up was 58.9 ± 26.7 months (1–180). Conclusions: When the results of the one study with a very high failure rate and of the cases that developed OSCC are not considered, the dental implant failure rate in OLP patients was 2.7% after a follow-up of approximately five years. Recommendations are given when treating OLP patients with dental implants.

The purpose was to integrate the available data published on desmoplastic ameloblastoma (DA) into a comprehensive analysis of its clinical/radiographic features. As it is not clear if the hybrid ameloblastoma has a unique biological behavior, the clinical/radiographic features of conventional DA with the hybrid variant were compared. An electronic search was undertaken in May/2019. Eligibility criteria included publications having enough clinical/radiographic/histological information to confirm the diagnosis. 128 publications reporting 285 DAs were included (246 central non-hybrid, 33 central hybrid, 6 peripheral). There was a statistically significant difference between non-hybrid and hybrid cases concerning lesion location, radiographic limits and size. In contrast to non-hybrid tumors that showed similar distribution in mandible and maxilla, a highly predominant mandible location was observed in the hybrid tumors. Also, non-hybrid lesions more often showed ill-defined radiographic margins, and were larger tumors than hybrid DAs. Enucleation with an additional therapy (either curettage or peripheral osteotomy) or resection led to a lower recurrence risk in comparison to curettage or enucleation without additional therapy. Location of the lesion and type of treatment are related to tumor recurrence. There are important differences in location and radiographic limits between hybrid and non-hybrid DAs, which support their classification as distinct lesions.

Purpose: This review aimed to evaluate the effects of the local delivery of antibiotics incorporated in implant surfaces on some quantitative parameters of bone formation. Materials and methods: An electronic search was undertaken in three databases (PubMed, Scopus, Embase) in addition to hand searching. The search was limited to animal experiments using endosseous implants combined with localized antibiotics release. Meta-analyses were performed for the percentages of bone volume (BV) and bone-to-implant contact (BIC). Results: Nine studies met the inclusion criteria. Several methods were identified for local delivery of antibiotics at the bone-implant interface, but the most commonly used method was by coating (incorporating the implant surface with the antibiotic agents). Different antibiotic agents were used, namely bacitracin, doxycycline, enoxacin, gentamicin, minocycline, tobramycin, and vancomycin. There was no statistically significant difference in the percentage of BIC between implants with or without localized antibiotic release (P = 0.59). The meta-analysis revealed higher BV around implants coated with antibiotics compared to control groups (without antibiotics) (P < 0.01). Conclusion: It is suggested that the local administration of antibiotics around implants did not adversely affect the percentage of direct bone contact around implants, with a tendency for a slightly better bone formation around implants when combined with local administration of antibiotics. It is a matter of debate whether these in vivo results will have the same effect in the clinical setting. However, the risk of bias of these studies may, to some extent, question the validity of these results. (C) 2020 The Author. Published by Elsevier Ltd on behalf of The Japanese Association for Dental Science.

Purpose: To compare clinical and esthetic outcomes between immediately loaded single implants placed with and without a fully guided surgical procedure. Materials and Methods: Patients with a missing maxillary tooth (second premolar to second premolar) were considered for inclusion in this 1-year prospective nonrandomized study. Exclusion criteria were general health contraindications for oral surgery besides the need for bone grafting or ridge augmentation. One group received digital implant planning, fully guided surgery, and immediate loading (DIL). The other group received freehand surgery and immediate loading (IL). Outcome measures were implant survival, marginal bone loss, soft tissue changes, papilla index, pink and white esthetic scores (PES and WES, respectively), and patient-reported outcome measures (PROMs). Results: Two of 21 implants failed in the DIL group soon after placement, resulting in a 1-year implant survival rate of 90.5%, while no implants failed in the IL group. Significantly higher papilla index scores and lower soft tissue changes were found for the DIL group compared to the IL group. No differences were found after 1 year regarding marginal bone loss, PES, WES, or PROMs. Conclusion: Within the limitations of this study, immediate loading in combination with fully guided surgery might negatively affect implant survival. Immediate loading, fully guided surgery, and a digital workflow appear to have a positive effect on early soft tissue adaptation.

The aim was to compare clinical and radiological features of the two juvenile ossifying fibroma (JOF) variants, trabecular (JTOF) and juvenile psammomatoid ossifying fibroma (JPOF). An electronic search was undertaken in March 2019. Eligibility criteria included publications having sufficient clinical, radiological, and histological information to confirm the diagnosis. A total of 185 publications and 491 cases were included. Most JOFs, including both variants, showed bone expansion, were painless, presented no cortical perforation and no secondary aneurysmal bone cyst, did not cause tooth root resorption, and had a mixed unilocular radiodensity appearance and well-defined limits on radiological examination. Patients with JPOF were on average older than those with JTOF. Enucleation and curettage was associated with a considerably high recurrence rate, regardless of the anatomical location or variant type of the lesion. Enucleation followed by either curettage or peripheral osteotomy showed lower recurrence rates than enucleation only. When resection was performed, only one case of JTOF presented recurrence. In conclusion, JOF lesions presented high rates of recurrence after treatment by curettage and enucleation only. Although surgical resection of JOFs resulted in the virtual absence of recurrence, enucleation followed by peripheral osteotomy/curettage should be the treatment of choice for both JOF variants to avoid the disfigurement usually associated with surgical resection.

Objectives: To investigate the molecular pathogenesis of implant‐associated peripheral giant cell granuloma (IA‐PGCG). Methods: A convenience sample of 15 IA‐PGCG cases was selected. Hotspot mutations of KRAS, FGFR1, and TRPV4 genes, previously reported in conventional giant cell lesions of the jaws, were investigated by Sanger sequencing. As these mutations could activate MAPK/ERK pathway, the expression of phospho‐ERK1/2 was also evaluated by immunohistochemistry. Results: KRAS mutations were detected in 8/15 (53.4%) samples. Similar to conventional peripheral giant cell granuloma, the KRAS mutations most frequently occurred in codon 146 (p.A146V, n = 3), followed by codon 12 (p.G12A and p.G12D, n = 1 each) and codon 14 (p.V14L, n = 1). Variants of unknown significance (VUS) were also detected in two cases, affecting codons 37 (p.E37K) and 127 (p.T127I). All samples showed wild‐type (WT) sequences for FGFR1 and TRPV4 genes. Consistent with MAPK/ERK pathway activation, all mononuclear cells of the lesion showed strong staining for phospho‐ERK1/2 protein in the immunohistochemical analysis. Conclusions: KRAS mutations and activation of the MAPK‐ERK signaling pathway occur in IA‐PGCG. This is the first study to demonstrate cancer‐associated gene mutations in a non‐neoplastic reactive condition associated with dental implants.

BACKGROUND: Implant-supported fixed partial dentures (ISFPDs) are one of the most common options to rehabilitate partially edentulous patients.

PURPOSE: To assess the clinical outcomes of ISFPDs.

METHODS: This retrospective study included all patients treated with ISFPDs with 2 to 6 prosthetic units at one specialist clinic. Implant/prosthesis failure and technical complications were the outcomes analyzed.

RESULTS: Six hundred and forty-two patients with 876 ISFPDs (2241 implants) were included, followed up for 108.0 ± 76.2 months. Eighty-eight prostheses and 112 implants (26 before, 86 after prosthesis installation) failed. The estimated CSR of ISFPDs at 30 years was 72.7%. Smokers presented lower implant survival than nonsmokers. Two hundred and ninety-nine ISFPDs (33.2%) presented technical complications. Bruxism was a factor to exert a higher risk of screw and implant fracture, and ceramic chipping. ISFPDs with cantilever presented higher risk of failure, and screw loosening/fracture. Prostheses supported by implants with internal abutment connection or with two pontics had higher risk of presenting ceramic chipping. Extension of the prosthesis did not seem to exert influence on prosthesis failure/complications.

CONCLUSIONS: ISFPDs presented good long-term prognosis. Implant failure was the main reason for ISFPD failure. The results suggest that bruxism and the presence of cantilever may contribute to the increased rate of mechanical complications and prosthesis failure.

OBJECTIVE: To assess the outcomes of implant-supported full-arch fixed dental prostheses (ISFAFDPs) and the supporting implants.

MATERIAL AND METHODS: This retrospective study included patients treated with ISFAFDPs at one specialist clinic. Implant/prosthesis failure and complications were the outcomes analyzed. Survival analysis methods were used.

RESULTS: A total of 709 patients with 869 ISFAFDPs (4,797 implants) were included, with a mean ± SD follow-up of 10.7 ± 7.2 years. A total of 353 implants and 62 prostheses failed. Estimated cumulative survival rates were as follows: 93.3% (95% CI 91.3, 95.3) after 10 years and 87.1% (95% CI 83.4, 90.8) after 20 years. Implants installed in bruxers, smokers, and maxilla had a lower survival than implants installed in non-bruxers, non-smokers, and mandible, respectively. A total of 415 ISFAFDPs (47.8%) presented technical complications, of which 67 (7.7%) presented only occurrences of loss/fracture of implant access hole sealing. Bruxism was a factor to exert a higher risk of screw loosening (HR 3.302; also in younger patients), screw fracture (HR 4.956), ceramic chipping/fracture (HR 5.685), and loss/fracture of acrylic teeth (HR 2.125; this last complication with higher risk also in men, in maxillae, and when the opposing jaw presented natural dentition or fixed prostheses). Patients with bruxism had a statistically significant higher risk of prosthesis failure than non-bruxers (HR 3.276).

CONCLUSIONS: ISFAFDPs presented good long-term prognosis. Failure of several supporting implants was the main reason for failure. The results of the present study strongly suggest that bruxism is an important contributor to implant and prosthesis failure, as well as to an increased prevalence of technical complications in ISFAFDPs.

The aim of this study was to compare the clinical outcomes of implant-supported overdentures (ODs) with either bar-clip or ball attachments. The implant, prosthesis failure, and technical complications were the outcomes analyzed in this retrospective clinical study conducted in a specialty clinic. Seventy-five patients with 242 implants supported by 76 ODs (36 maxillary, 40 mandibular) were included in the study and followed up for 88.8 ± 82.9 months (mean ± standard deviation). Bar-clip and ball attachments were used in 78.9% and 21.1% of the cases, respectively. Forty-three implant failures (17.8%) in 17 prostheses (17/76; 22.4%) were observed in this study. The average period of implant failure was 43.3 ± 41.0 months, and most of them were maxillary turned implants. The bar-clip system demonstrated more complications in the attachment parts compared to the ball attachment system. Poor retention of the prosthesis was similar between the two systems. Loss of implants resulted in the failure of 10 ODs in this study. ODs opposed by natural dentition or fixed prostheses presented with more complications. The Cox proportional hazards model did not show a significant effect on prosthesis failure for any of the factors. These findings indicated that patients with ODs need constant maintenance follow-ups to address the technical complications and perform prosthodontic maintenance regardless of the attachment system used.