INTRODUCTION: Studies demonstrated that the accuracy of intra-oral scanners can be compared with conventional impressions for most indications. However, little is known about their applicability to take impressions of multiple implants. AIM: The aim of this study was to evaluate the accuracy of four intra-oral scanners when applied for implant impressions in the edentulous jaw. MATERIAL AND METHODS: An acrylic mandibular cast containing six external connection implants (region 36, 34, 32, 42, 44 and 46) with PEEK scanbodies was scanned using four intra-oral scanners: the Lava C.O.S. and the 3M True Definition, Cerec Omnicam and 3Shape Trios. Each model was scanned 10 times with every intra-oral scanner. As a reference, a highly accurate laboratory scanner (104i, Imetric, Courgenay, Switzerland) was used. The scans were imported into metrology software (Geomagic Qualify 12) for analyses. Accuracy was measured in terms of trueness (comparing test and reference) and precision (determining the deviation between different test scans). Mann-Whitney U-test and Wilcoxon signed rank test were used to detect statistically significant differences in trueness and precision respectively. RESULTS: The mean trueness was 0.112 mm for Lava COS, 0.035 mm for 3M TrueDef, 0.028 mm for Trios and 0.061 mm for Cerec Omnicam. There was no statistically significant difference between 3M TrueDef and Trios (P = 0.262). Cerec Omnicam was less accurate than 3M TrueDef (P = 0.013) and Trios (P = 0.005), but more accurate compared to Lava COS (P = 0.007). Lava COS was also less accurate compared to 3M TrueDef (P = 0.005) and Trios (P = 0.005). The mean precision was 0.066 mm for Lava COS, 0.030 mm for 3M TrueDef, 0.033 mm for Trios and 0.059 mm for Cerec Omnicam. There was no statistically significant difference between 3M TrueDef and Trios (P = 0.119). Cerec Omnicam was less accurate compared to 3M TrueDef (P < 0.001) and Trios (P < 0.001), but no difference was found with Lava COS (P = 0.169). Lava COS was also less accurate compared to 3M TrueDef (P < 0.001) and Trios (P < 0.001). CONCLUSIONS: Based on the findings of this in vitro study, the 3M True Definition and Trios scanner demonstrated the highest accuracy. The Lava COS was found not suitable for taking implant impressions for a cross-arch bridge in the edentulous jaw.

Purpose The study aims to evaluate the long-term clinical outcome of immediate loading of implants in the edentulous mandible. Materials and Methods Patients were treated at least 1 year prior to evaluation, with four to five implants and an immediate provisional bridge in the edentulous mandible. They were invited for a clinical examination, which included the removal of the bridge, probing, perio-testing, clinical photographs, and a new radiograph to determine the bone level. Also, patients were requested to answer the OHIP-14 questionnaire to rate their satisfaction with the treatment Results Forty-six patients (21 men, 25 women), mean age 60 years (SD 8.5, range 43-77), were treated with 211 implants. One implant failed to integrate, resulting in a survival rate of 99.5%. After a mean follow-up of 90 months (SD 45, range 17-143), the mean bone level was 1.17mm (SD 0.49, range 0.36-4.88). The mean Periotest value was -5.48 (SD 0.883, range -2 to -7). The mean probing depth was 2.04mm (SD 0.71, range 1.00-8.25). There were 83.3% of the implants that demonstrated no bleeding at probing. Calculus was observed at 13.9% of the abutments. Around one implant (0.5%), suppuration was seen after probing. There was a highly significant correlation between bone loss and probing depth (p<.001). Overall, patients were very satisfied, with 69.6% scoring their treatment as excellent Conclusion Immediate loading of surface-enhanced implants is a highly predictable and successful treatment modality in the edentulous mandible.

Aim To compare the long-term clinical outcome of turned vs. moderately rough implants. Materials and methods Patients treated with implants in the edentulous mandible and/or maxilla were invited for a clinical examination. After prosthesis removal, the pocket depth was measured and the bleeding scored. Also, a new radiograph was taken for bone loss evaluation. Patients were also requested to rate their satisfaction with the treatment Results One hundred and ninety-seven implants in 33 patients were evaluated. After a mean follow-up of 172months (SD 42, range 120-252), the mean loss was 1.61mm (SD 1.35, range 0.00-8.25). Bone loss was higher in the maxilla compared to the mandible (P<0.001), and at implants, that was restored on implant level (P=0.003). Multivariate analyses demonstrated a significant effect of implant surface roughness and time of loading on bone loss. Smoking, on the other hand, did not affect the outcome. Mean pocket probing depth was 3.64mm (SD 0.96, range 1.25-7.25). A total of 4.1% of the implants demonstrated signs of peri-implantitis. The overall patient satisfaction rate was 98.5 Conclusion Implant treatment in the edentulous jaw has a predictable long-term outcome with limited complications.

Background Single implants were introduced in the 1980s, but long-term follow-up is scarce. Purpose The study aims to retrospectively investigate the prosthetic survival and complication rates of single implants in periodontally healthy patients after 16-22 years, and to evaluate the influence of different prosthetic procedures Materials and Methods Patients with a single implant were recalled for clinical examination. Prosthetic procedures included single-tooth (ST) and CeraOne (CO) abutments supporting a porcelain-fused-to-metal (PFM), all-ceramic (CER), or gold-acrylic (ACR) crown. Prosthetic survival, success, and occurrence of biological, technical, and aesthetic complications were obtained. Procedures were compared by log-rank tests Results Fifty patients attended the examination. All implants were functional; however, 15% of abutments and 27% of crowns had been renewed. Replacements (1/4) were related to technical issues whereas the main cause was aesthetics. The abutment cumulative survival rate (CSR) differed significantly between ST-PFM (74%), ST-ACR (0%), and CO reconstructions (97%). The crown CSR was significantly lower for ST-ACR crowns (0%) compared with ST-PFM (68%) and CO (81%). Thirty-nine percent of implants remained complication free throughout the mean 18.5 years. Complications (1/3) required component replacement, and 53% occurred within 5 years after surgery Conclusion Prosthetic survival rates of single implants are encouraging after 16 to 22 years. However, 66% of the patients encountered at least one complication during follow-up.

The aim of this study was to evaluate the accuracy, in terms of trueness and precision, of optical dental scanners. An experimental acrylic resin cast was created and digitized using a microcomputed tomography (microCT) scanner, which sewed as the reference model. Five polyether impressions were made of the acrylic resin cast to create five stone casts. Each dental digitizer (Imetric, Lava ST, Smart Optics, KaVo Everest) made five scans of the acrylic resin cast and one scan of every stone cast. The scans were superimposed and compared using metrology software. Deviations were calculated between the datasets obtained from the dental digitizers and the microCT scanner (= trueness) and between datasets from the same dental digitizer (= precision). With exception of the Smart Optics scanner, there were no significant differences in trueness for the acrylic resin cast. For the stone casts, however, the Lava ST performed better than Imetric, which did better than the KaVo scanner. The Smart Optics scanner demonstrated the highest deviation. All digitizers demonstrated a significantly higher trueness for the acrylic resin cast compared to the plaster cast, except the Lava ST The Lava ST was significantly more precise compared to the other scanners. Imetric and Smart Optics also demonstrated a higher level of precision compared to the KaVo scanner. All digitizers demonstrated some degree of error. Stone cast copies are less accurate because of difficulties with scanning the rougher surface or dimensional deformations caused during the production process. For complex, large-span reconstructions, a highly accurate scanner should be selected.

Background: The All-on-4® concept is widely applied for full-arch rehabilitations, using two tilted and two axially loadedimplants in order to overcome anatomical constraints.Purpose: The aim of this study was to assess the survival and individual success of implants immediately loaded with anAll-on-4 full-arch screw-retained prosthetic bridge i n fully edentulous mandibles or maxillae over up to 3 years.Materials and Methods: In total, 20 patients with atrophic jaws (9 maxillae, 11 mandibles) were treated with computer-guided flapless surgery and immediately provided with a provisional bridge. The final prosthesis was delivered after6 months. In total, 80 TiUnite™ Brånemark implants were placed. Radiographs were taken after surgery and 1 and 3 yearslater.Results: A 3-year survival rate of 100% was seen for all implants, both in lower and in upper jaw. None of the temporaryor definite prostheses were lost over the follow-up period of 3 years. After 1 year, the mean bone loss was 1.13 mm (SD 0.94;range −0.1 to 3.8), and after 3 years, it was 1.61 mm (SD 1.40; range 0 to 5). The mean bone loss between the 1-year and3-year follow-ups was 0.48 mm (SD 0.66; range −1.2 to 3.6). This difference was statistically significant (p < .001), indicativeof ongoing bone loss. Twenty-six percent of the implants had bone loss above 1.5 mm after 1 year, but after 3 years, 30%of the implants had already lost more than 1.9 mm.Conclusion: The implant and prosthetic survival was 100%, and patients benefited from the All-on-4 treatment. However,unacceptable ongoing bone loss was seen in 49.2% of the patients; this may be a warning sign for future problems and needsclinical attention. Overloading and surgery-related aspects need to be investigated as potential explanations.

Introduction: Implant dentistry in undergraduate education is predominantly theoretical or prosthetics oriented. Clinical experience with implant surgery could provide students a better understanding of alternatives for tooth replacements. This study describes an implant dentistry programme for undergraduate students, which included surgical placement of implants. The study presents the clinical outcomes of the programme, patients' satisfaction and students' attitudes/perceptions. It reflects on barriers and problems encountered during implementation and provides suggestions for other institutions. Materials and methods: Thirty-six students placed one implant each for a single tooth replacement after careful radiographic assessment and pre-surgical planning. One-stage surgery was performed under one-to-one supervision. Crowns were cemented on individual abutments 3-6 months later. Crestal bone loss was assessed radiographically immediately after surgery, at crown placement and after 1 year of loading. Questionnaires were used to investigate patients' perspectives and students' opinions towards the programme, as well as their perceived level of competence. Results: Thirty-six implants were placed in 27 patients; two (5.6%) failed prior to loading; mean bone loss from time of surgery to crown placement was 1.41 mm and remained unchanged thereafter, reflecting implant success. Overall, patients were satisfied and the majority would repeat the treatment by a student. The students thought it was a valuable experience, although they realised that additional education is necessary to perform implant surgery without supervision. Conclusion: Implant placement by undergraduate students resulted in acceptable clinical outcome parameters, patient satisfaction and positive student perceptions. These findings support the further development of clinical implant education in undergraduate dental curricula.

Introduction: To promote consensus on implant dentistry university education in Europe, a workshop amongst university teachers and opinion leaders was organised in 2008. As a result, guidelines on both under-and postgraduate education were issued. This study aims to investigate the current status of university teaching of implant dentistry and the impact of the recommendations for teaching and assessment, 5 years after the first consensus. Finally, this report attempts to identify future directions in education within the discipline. Materials and methods: An online survey was distributed amongst 105 academic leaders in implant education in Europe, and 52 questionnaires were returned (response rate 50%). Results: The average amount of implant dentistry in undergraduate curricula has increased to 74 h, compared to 36 h in 2008, and the inclusion of pre-clinical and clinical education has increased. No change occurred with regard to the aimed competence levels. It was suggested that certain implant procedures including surgery should be provided by dentists after attending additional courses, whilst complex treatments will still require specialist training. The 2008 workshop guidelines have been implemented to a varying extent (25-100%) in under-and postgraduate education. Main reported implementation barriers included limited time availability in the curriculum and limited financial/material resources. Future discussions about implant dentistry in Europe should be focused towards integration in current dental curricula, approaches to overcome barriers and the relations with and role of industrial partners. Conclusion: Implant dentistry is increasingly integrating in undergraduate dental education. Development of the consensus guidelines in 2008 may have facilitated this process. Nevertheless, further progress is needed on all educational levels to align training of professionals to the growing treatment needs of the population.

This prospective study evaluated clinical results of immediately loaded Biomet 3i implants with different surface topographies. Thirty-three periodontally compromised patients received 163 implants (130 in the maxilla and 33 in the mandible; 132 NanoTite and 31 Osseotite). After a mean loading period of 57 months, the survival rate was 96.3%. Mean crestal bone loss was 1.6 mm. No difference in bone loss was detected between the two surfaces. Only 6% of the implants had peri-implantitis based on total bone loss above 2 mm from the day of surgery in conjunction with probing depths of > 4 mm.

The present study describes the development of a microsphere capsule based on polylactide-co-glycolide (PLGA) loaded with simvastatin that was subsequently incorporated into synthetic bone cement. The osteogenic effect of simvastatin-loaded bone cement was in a critical sized defect in vivo to test the hypothesis the biologic response would be different depending on the dosage of simvastatin applied to bone cement. Our results showed that simvastatin loaded PLGA microspheres can be successfully obtained through O/W emulsion/solvent evaporation method with appropriate morphologic characteristics and high encapsulation efficiency for incorporation in bone cements. The biodegradable characteristic of the microspheres successfully presented a slow release and the duration of the release lasted for more than 1 month. The in vivo experiment revealed that the microspheres containing simvastatin significantly enhanced bone formation in the rabbit calvaria critical size defect.