Objective: To identify common resilience factors against non-communicable diseases (dental caries, diabetes type II, obesity and cardiovascular disease) among healthy individuals exposed to chronic adversity.

Materials and methods: The databases MEDLINE (via PubMed), Scopus and CINAHL were searched. Observational studies in English assessing resilience factors among populations living in chronic adversity were included. Intervention studies, systematic reviews, non-original articles and qualitative studies were excluded. There were no restrictions regarding publication year or age. No meta-analysis could be done. Quality assessments were made with the Newcastle-Ottawa scale (NOS).

Results: A final total of 41 studies were included in this systematic review. The investigated health resilience factors were divided into the following domains: environmental (community and family) and individual (behavioural and psychosocial). A narrative synthesis of the results was made according to the domains.

Conclusions: Individual psychosocial, family and environmental factors play a role as health resilience factors in populations living in chronic adversity. However, the inconclusive results suggest that these factors do not act in isolation but interplay in a complex manner and that their interaction may vary during the life course, in different contexts, and over time.

ObjectiveThe aim was to identify caries active individuals among adults by using a trajectory model of longitudinal data from the Swedish national registry (SKaPa) and comparing them with published data from the Dunedin cohort.Materials and methodsData from two different age groups (30- and 40-year-olds) followed for 10 years were retrieved from SKaPa and were compared with published longitudinal birth-cohort data from the Dunedin study. Using the trajectory model, the subjects were divided into three different trajectories according to their caries development over time (i.e. high, 15%; moderate, 45%; low, 40%).ResultsCaries experience, as measured by mean decayed, missing, and filled surfaces (DMFS) index, revealed significant differences among the three trajectories in both age groups. The patterns were similar to those observed in the Dunedin cohort. The mean increase in DMFS during the 10-year follow-up period from SKaPa was significantly higher for the high trajectories in both age groups compared with the moderate and low trajectories.ConclusionsThe method using three trajectories for presentation of caries experience over time, may be a useful tool to identify subjects with different disease activities. Identification of subjects in the high caries experience trajectory may increase the possibility to explore and evaluate more effective caries prevention for this group in the future.

Odontoblasts are thought to be involved in innate immunity but their precise role in this process is not fully understood. Here, we assess effects of lipopolysaccharide (LPS) and lipoteichoic acid (LTA), produced by Gram-negative and Gram-positive bacteria, respectively, on matrix metalloproteinase-8 (MMP-8), interleukin-6 (IL-6) and cathelin-related antimicrobial peptide (CRAMP) expression in odontoblast-like MDPC-23 cells. Gene activity and protein production was determined by quantitative real-time RT-PCR and ELISA, respectively. Cellular expression of CRAMP was determined by immunocytochemistry. Stimulation with LTA (5 and 25 µg/ml) but not LPS (1 and 5 µg/ml) for 24 h enhanced IL-6 mRNA expression. The LTA-induced up-regulation of IL-6 mRNA levels was associated with increased IL-6 protein levels. Stimulation with either LPS or LTA for 24 h lacked effect on both MMP-8 transcript and protein expression. Immunocytochemistry disclosed that MDPC-23 cells expressed immunoreactivity for CRAMP. MDPC-23 cells showed mRNA expression for CRAMP, but stimulation with either LPS or LTA did not modulate CRAMP transcript expression. We show that MDPC-23 cells possess immune-like cell properties such as LTA-induced IL-6 production and expression of the antimicrobial peptide CRAMP, suggesting that odontoblasts may modulate innate immunity via these mechanisms.

Deep caries presents a dilemma in terms of which treatment that will render an optimal prognosis by maintaining pulp vitality with absence of apical pathology. Previously, 2 randomized clinical trials were performed testing the short-term effects of stepwise carious tissue removal versus nonselective carious removal to hard dentin with or without pulp exposure. The aim of this article was to report the 5-y outcome on these previously treated patients having radiographically well-defined carious lesions extending into the pulpal quarter of the dentin but with a well-defined radiodense zone between the carious lesion and the pulp. In this long-term study, 239 of 314 (76.2%) patients were analyzed. The stepwise removal group had a significantly higher proportion of success (60.2%) at 5-y follow-up compared with the nonselective carious removal to hard dentin group (46.3%) ( P = 0.031) when pulp exposures per se were included as failures. Pulp exposure rate was significantly lower in the stepwise carious removal group (21.2% vs. 35.5%; P = 0.014). Irrespective of pulp exposure status, the difference (13.3%) was still significant when sustained pulp vitality without apical radiolucency and unbearable pain was considered (95% confidence interval, 3.1-26.3, P = 0.045). After pulp exposure, only 9% ( n = 4) of the analyzed patients were assessed as successful, indicating that the prognosis is highly dubious following conventional pulp-capping procedures (direct pulp capping or partial pulpotomy) in deep carious lesions in adults. In conclusion, the stepwise carious removal group had a significantly higher proportion of pulps with sustained vitality without apical radiolucency versus nonselective carious removal of deep carious lesions in adult teeth at 5-y follow-up (ClinicalTrials.gov NCT00187837 and NCT00187850).

OBJECTIVE: Dental caries is a process driven by acids produced by oral microorganisms followed by degradation of the dentine collagen matrix by proteolytic enzymes. Matrix metalloproteinases (MMPs) have been suggested to contribute to caries by degrading collagen. The aim of this study was to develop a method for generating demineralized dentine matrix substrate (DDM) maintaining MMP-8 bioactivity and no interference with later assays. Such a substrate would allow study of the effects of various treatments on MMP-8 activity and collagen degradation in demineralized dentine. DESIGN: Human dentine was powderized in a tissue grinder and frozen (-80°C). The powder was demineralized in dialysis tubes, using EDTA or acetic acid. The demineralized dentine matrix (DDM) was harvested and analyzed for collagen content using SDS-PAGE. The DDM was subsequently suspended in PBS or TESCA buffer. Protein, MMP-8 (ELISA) and collagen (HYP) was analyzed directly or after 1 wk. RESULTS: EDTA or acid demineralization of dentine using dialysis yielded a substrate rich in collagen coupled with preserved MMP-8 activity. Collagen degraded in room temperature, assessed by higher HYP amounts in the soluble fraction of DDM after one wk, indicating that the methods used preserved active DDM-components after the demineralization process. CONCLUSIONS: The presented demineralization methods both provided insoluble DDM substrates suitable for further intervention studies. However, it was found that the substrates differed depending on the demineralization method and buffers used. This needs further study to find an optimal technique for generating DDM with retained proteins as well as enzymatic bioactivity.

The caries process in dentin involves the degradation of both mineral and organic matrix. The demineralization has been demonstrated to be caused by bacterial acids. How-ever, the collagen degradation is considered to be initiated by endogenous proteolytic enzymes, mainly collagenolytic matrix metalloproteinases (MMPs). This paper aims to relate salivary MMP-8 (or salivary collagenase-2) and tissue inhibi-tor of MMP (TIMP-1) levels to manifest caries in a large num-ber of subjects. A random sample of 451 adults (aged 18-87 years) living in the south of Sweden was included in this study. Standard clinical examinations were performed, and stimulated saliva was collected and analyzed for concentra-tions of MMP-8, TIMP-1 and total protein, using an immuno-fluorometric assay, an enzyme-linked immunosorbent assay and the Bradford assay, respectively. Salivary numbers of mutans streptococci and lactobacilli were determined using a chair-side kit. Subjects with manifest caries lesions present-ed with elevated levels of MMP-8 (p < 0.001) as well as total protein, MMP-8/TIMP-1 ratio, bleeding on probing and plaque index (p = 0.05) compared with subjects without manifest caries. Multiple linear regression analysis with car-ies as the dependent variable revealed MMP-8 as the only significant explanatory variable (p < 0.001). TIMP-1 was not significant in any case. Using MMP-8 as the dependent vari-able revealed total protein concentration, caries lesions (p ≤ 0.001) and salivary secretion rate (p = 0.05) as explanatory variables. In conclusion, our data reveal that subjects with manifest caries lesions have elevated levels of salivary MMP-8 relative to subjects with no caries lesions.

Dental caries is a common disease all over the world, despite the fact that it can be both effectively prevented as well as treated. It is driven by acids produced by oral microorganisms as a consequence of their metabolism of dietary carbohydrates. Given enough acid challenge, eventually the enamel barrier will be broken down, and the carious lesion will extend into underlying hard tissue, forming a macroscopic cavity in the dentine. In comparison to plaque biofilm on enamel, this dentine carious lesion will form a vastly different environment for the residing microorganisms. The environment will influence the types and numbers of microorganisms that will be able to colonize the dentine caries lesion. The overall aims for this thesis is to enumerate and further study microorganisms found in established dentine caries lesions, and also to illuminate how host-derived proteolytic enzymes might contribute to this degradation, in order to better understand the caries process in dentine, but also to find incitements for new methods to influence the natural progression of caries lesions. In Paper I, the number of remaining viable microorganisms after completed excavation using two different excavation methods were investigated. Samples of carious dentine tissue was collected before and after excavation, and cultivated on different agar media in different atmospheres. Analysis was performed by counting the number of colony forming units (cfu). Key findings: Numbers of remaining microorganisms after excavation was low for both methods, but some microorganisms always remained in the cavity floors even when the cavities were judged as ”caries free” using normal clinical criteria. In Paper II, the acid tolerant microbiota in established dentine caries lesions were investigated. Samples were taken as in Paper I, but on three levels (superficial, center of lesion, cavity floor). The samples were cultivated in anaerobic conditions on solid pH-selective agar media of different acidity. Key findings: Each investigated lesion harbored a unique microbiota, both in terms of species composition and numbers of microorganisms. This indicate that various combinations of aciduric microorganisms can colonize, survive in and probably also propagate dentine carious lesions. We also found that solid pH-selective agars successfully can be used to select acid tolerant microorganisms in caries lesions. This would preserve their phenotypic traits for further study. In Paper III, the relation between salivary levels of matrix metalloproteinase-8 (MMP-8), salivary levels of tissue inhibitor of MMP (TIMP-1) and presence of manifest caries lesions in a large number of subjects was investigated. Saliva samples were collected and analyzed for concentrations of MMP-8, TIMP-1 and total protein using immunofluorometric assay, enzyme linked immunosorbent assay and Bradford assay, respectively. Key findings: Subjects with manifest caries lesions had significantly elevated levels of salivary MMP-8 compared to subjects without caries lesions. TIMP-1 was not significant in any case. In Paper IV, a new method for generating bioactive demineralized dentine matrix substrate (DDM) was developed, using a dialysis system and two different demineralization approaches (acetic acid (AA) or EDTA). The generated DDM was subsequently analyzed for presence of type 1 collagen, active MMP-8 and hydroxyproline (HYP) levels using SDS-PAGE, ELISA or immunofluorescence assay. Key findings: Both demineralization methods produced a substrate rich in collagen and with preserved MMP-8 activity. The report presents new knowledge on the composition of the acid tolerant dentine caries microbiota from three levels in dentine carious lesions and on the efficacy of operative caries removal on the numbers of viable microorganisms in the caries free cavity using two different operative methods. Moreover, the basic mechanisms behind collagen degradation in the dentine caries process are studied from both a clinical and laboratory perspective. The report provides a reference for further studies on dentine caries microbiology and dentine caries collagen degradation mechanisms, both of which are only known in part.

Objectives: Long term follow-up data based on randomised clinical trials are needed in relation to deep caries treatment. The aim of the present trial is to investigate the beneficial and harmful long term effects of stepwise excavation during two visits versus one completed excavation of deep caries in permanent teeth in adults. Methods: Consecutive patients contacting clinical units in Sweden and Denmark were included. The trial is a centrally randomised patient- and observer-blinded multicenter trial, with two parallel intervention groups. A sample size calculation showed that 134 patients were needed in each group. Taking dropouts into account, a total of 314 patients fulfilled well-defined inclusion and exclusion criteria and were centrally block-randomised stratified by age and pain. Inclusion criteria: (i) Person ≥ 18 yrs having deep caries with or without pain (ii) x-ray showing primary caries into the inner 1/4 of the dentin, with the presence of a radiopaque zone at the pulpal wall. Success was defined as unexposed pulp with sustained pulp vitality without apical radiolucency after follow-up. Blinded evaluation of 1½ follow-up has previously been carried out in 106 patients (stepwise excavation group) and 93 patients (direct complete excavation) (Bjørndal et al. 2010, EJOS). Results: At 3-5 yr follow up there was a statistically significantly higher success with stepwise excavation [difference: 11.5%, 95% confidence interval (0.5; 22.2)] versus a direct complete excavation procedure, being similarly with the short term follow-up data. 53.3% (n = 102) of the material has been controlled and no significant differences were noted between the two intervention groups in terms of patients not yet controlled, lost patients and failures (Table). Conclusion: A stepwise excavation procedure still seems preferable after a long term follow up and presumably related to the reduced risk of exposing the inflamed pulp associated with deep caries.

Less invasive excavation methods have been suggested for deep caries lesions. We tested the effects of stepwise vs. direct complete excavation, 1 yr after the procedure had been carried out, in 314 adults (from six centres) who had received treatment of a tooth with deep caries. The teeth had caries lesions involving 75% or more of the dentin and were centrally randomized to stepwise or direct complete excavation. Stepwise excavation resulted in fewer pulp exposures compared with direct complete excavation [difference: 11.4%, 95% confidence interval (CI) (1.2; 21.3)]. At 1 yr of follow-up, there was a statistically significantly higher success rate with stepwise excavation, with success being defined as an unexposed pulp with sustained pulp vitality without apical radiolucency [difference: 11.7%, 95% CI (0.5; 22.5)]. In a subsequent nested trial, 58 patients with exposed pulps were randomized to direct capping or partial pulpotomy. We found no significant difference in pulp vitality without apical radiolucency between the two capping procedures after more than 1 yr [31.8% and 34.5%; difference: 2.7%, 95% CI ()22.7; 26.6)]. In conclusion, stepwise excavation decreases the risk of pulp exposure compared with direct complete excavation. In view of the poor prognosis of vital pulp treatment, a stepwise excavation approach for managing deep caries lesions is recommended.

Objective: To investigate the acid tolerant microflora at different levels in established dentine caries lesions using solid pH-selective media, as acid stress might be a major selective determinant in dentine caries ecosystems. Methods: Primary dentine caries lesions (vital teeth, no symptoms) in five patients were sampled aseptically with a rose-bur at three levels: superficially, in the centre and the bottom of the lesion, when it was considered clinically caries free using visual and tactile criteria. Samples were incubated on neutral (blood agar) and pH-selective (Todd-Hewitt agar buffered to pH 4.0, 4.5, 5.0, 5.5) agar. Numbers of colony-forming units (cfu) were determined and colonies were characterized morphologically and with enzymatic- and sugar fermentation tests. Results: The total numbers of bacteria recovered from the pH-neutral agars did not decrease significantly with lesion depth (median blood agar: 6.3×103 superficially; 2.2×103 bottom) whereas cfu recovery from low pH agars decreased with increasing agar acidity. The composition of the aciduric microflora varied both between subjects and between sample sites within the lesions. Gram-positive cocci were most abundant, but with lower pH and deeper sampling sites, the numbers of lactobacilli and other Gram-positive rods increased. Mutans streptococci were found at all sampling depths. S. anginosus, S. constellatus, S. crista, S. gordonii, S. intermedius and S. sanguis were found less frequently. Conclusions: The study clearly indicates that many different microorganisms can be recovered on pH 5.5 agars and thus survive in low pH environments. pH 5.5 is quite sufficient to moderately demineralize dentine, and aciduric microorganisms should thus have the potential to contribute to the dentine caries process. Approved by the ethical committee at Lund University. Funded by Faculty grants.

Objectives: To investigate the acid tolerant microflora in dentine caries, with special respect to oral streptococci cultivable on pH-selective agar media, as acid stress might be a major selective force in dentine caries. Methods: Five patients with primary dentine caries lesions (vital teeth, no symptoms) participated in the study. Caries lesions were excavated aseptically under rubber-dam using rose-burs. Dentine sampling was performed using sterile rose-burs at 3 levels: superficially, in the centre and in the cavity floor. Samples were incubated on neutral (blood agar) and pH-selective agars (Todd-Hewitt agar with citrate-phosphate buffer; pH 4.5, 5.0 and 5.5). Numbers of colony-forming units (CFUs) were determined, characterized morphologically, isolated to blood agar and then identified (Gram-reaction, cell- and colony morphology). Each colony type was frozen in skim milk (158 isolates). Isolates described as streptococci were revived, re-incubated (65 isolates) and further characterized by enzymatic- and sugar fermentation tests. Results: The same bacterial counts were recovered from superficial, center and cavity floor, respectively. Each dentine sample exhibited a unique microflora. There was no significant difference in proportions of aciduric microorganisms in different levels in the lesion. Approximately 38% (superficial), 5% (centre) and 38% (cavity floor) of the total cultivable microbiota was able to grow at pH 5.5, a pH value critical for demineralisation of dentine. The acid-tolerant streptococcal isolates included mutans streptococci, S. anginosus, S. constellatus and a group of unidentified streptococci. Lactate consuming taxa were found in one case, but only at pH 5.5. Conclusion: There was no significant difference in numbers of microorganisms on different levels in the lesion. Composition of the dentine caries microflora differs from lesion to lesion. The dentine caries microflora consortia differ from lesion to lesion. A common property of these bacteria was acid tolerance. Approved by the ethical committee Lund University. Funded by Faculty grants.

To measure the amount of viable bacteria after excavation using conventional rose-bur or the chemo-mechanical Carisolv method, a total of 22 lesions were analyzed (one vital tooth per patient) in this open, controlled and randomized study. Two samples per lesion were taken under aseptic conditions using a rose-bur, one superficially in the caries lesion and one after completed excavation. In in vitro tests more material was collected from the hard caries free dentine as compared to the carious dentine. The samples were incubated on blood agar (aerobically and anaerobically), Rogosa (SL) agar and mitis salivarius (MS) agar. For blood agar (aerobic) both methods resulted in a significant decrease in CFU, for blood agar (anaerobic) and MS agar only the Carisolv method resulted in a significant decrease in CFU and for SL agar neither method resulted in a significant decrease in CFU. Comparing CFU before and after excavation, a considerable reduction of CFU was seen ranging from 10(1) to 10(4). Comparing the excavation methods, there were no significant differences, except in the case of blood agar (aerobic), which showed that Carisolv excavation was more effective in reducing CFU. This study indicated that bacterial sampling collected more material from hard dentine as compared from soft. Remaining bacteria after excavation were low in both groups. The Carisolv method seemed to remove bacteria at least up to and possibly beyond the extent of conventional drilling.