Objectives. Resin-dentin bond strength decreases over time. This reduction is related to the loss of hybrid layer integrity. Collagenolytic enzymes, especially matrix metalloproteinases (MMPs), are responsible for the degradation of the collagen matrix of the hybrid layer. Various MMP inhibitors with the ability to prevent enzymatic degradation have been identified. This study aimed to systematically review the literature for studies which evaluated the effect of MMP inhibitors on the immediate and aged dentin bond strengths. Study SelectionScreening and analysis were carried out by two reviewers. Two databases were searched, and from a total of 740 articles, 43 were accepted for full review. 21 articles with 0.2%–2% chlorhexidine (CHX) treatments were included for meta-analysis. A risk of bias assessment was performed on all studies chosen for meta-analysis. A variety of MMP inhibitors have been studied, CHX being the most widely used. Conclusions. A clear trend for a lower loss of dentin bond strength was observed with different MMP inhibitors. In meta-analysis, no significant difference was seen between the CHX and control in the immediate bond strengths. Bond strengths in the CHX group were significantly higher than the control group after aging ( ). The percentage of fractures occurring at the adhesive interface increased after aging. Five out of 21 studies included in the meta-analysis had high and the rest medium risk of bias. More long-term studies with lower risks of bias should be carried out to increase the reliability of results. Clinical RelevanceThe use of MMP inhibition with chlorhexidine can be recommended to increase the longevity of resin-dentin bond strength.

The main aim of this cross-sectional study was to investigate the prevalence and severity of erosive tooth wear and its association with dental caries and socio-demographic factors among middle-aged Finnish adults. Of the total Northern Finland Birth Cohort 1966 (n = 12,058), a convenience sample (n = 3181 adults) was invited for an oral health examination of which 1962 (61.7 %) participated, comprising the final study group. Clinical examinations were carried out by trained and calibrated dentists. Erosive tooth wear was assessed by sextants using the Basic Erosive Wear Examination Index (BEWE, 0–18) and dental caries at surface level using the ICDAS criteria (0–6). Socio-demographic data were obtained from a postal questionnaire. A logistic regression model was generated to test the association of the variables. The prevalence of erosive tooth wear was 75 % and the mean of the BEWE sum score was 3.4 (SD 3.30). Almost half of the members needed non-invasive or invasive measures to prevent further progression of the condition. Of those with erosive lesions, 14.6 % suffered from severe erosive tooth wear. There was a strong positive relationship between the presence of severe erosive tooth wear (BEWE sum score ≥9) and male gender and restorative treatment need. Erosive tooth wear is a common finding in Finnish adult population; almost one in ten suffer from severe erosive tooth wear. Restorative treatment need seems to be associated with severe erosive tooth wear.

Objective: To assess the influence of self-reported intrinsic factors [gastroesophageal reflux disease (GERD), long-term alcoholism, long-term heavy use of alcohol and multiple pregnancies] on erosive tooth wear in a middle-aged cohort sample. Materials and Methods: Of the total Northern Finland Birth Cohort (NFBC 1966), a convenience sample (n = 3,181) was invited for an oral health examination in 2012-2013, of which 1,962 participated, comprising the final study group. Erosive tooth wear was assessed by sextants using the Basic Erosive Wear Examination Index (BEWE, 0-18). Clinical data were supplemented by questionnaires conducted in 1997/1998 and 2012/2013. The participants were divided into severe (BEWE sum ≥9) and no-to-moderate (BEWE sum 0-8) erosive wear groups, and the logistic regression model was applied. Results: Selected intrinsic factors were quite rare in this cohort sample and explained only 5.9% of the difference in the prevalence and severity of erosive wear. Daily symptoms of GERD [odds ratio (OR) 3.8, confidence interval (CI) 1.2-12.0] and hyposalivation (OR 3.8, CI 1.2-11.8) were the strongest risk indicators for severe erosive wear. Additionally, variables associated with an elevated risk for severe erosive wear were diagnosed alcoholism at any point (OR 2.5, CI 0.7-9.7) and self-reported heavy use of alcohol in both questionnaires (OR 2.0, CI 0.6-6.2). Even low-dose long-term consumption of alcohol was associated with erosive wear. Conclusions: In this cohort sample, intrinsic factors such as GERD or alcoholism alone are relatively uncommon causes of erosive tooth wear. The role of long-term use of alcohol in the erosion process may be bigger than presumed.

The aim of this study was to investigate the prevalence of smoking and snuffing habits in association with dental caries occurrence in a male cohort born in the early 1990s in Finland. The impact of health behaviours and factors related to the place of residence were included in analyses. Oral health of 8537 conscripts was screened in a cross-sectional study. In the same occasion they also answered a questionnaire covering their smoking and snuffing habits and other background factors. The residence-related factors were obtained from the Defence Forces' database. Cross-tabulation together with chi-squared test and generalized linear mixed models were used for analyses. Almost forty per cent (39.4%) of the men reported smoking daily and 9.0% reported daily snuffing. Restorative treatment need of those who reported frequent smoking was more than 2-fold (mean DT = 2.22) compared to the non-smokers (mean DT = 1.07). Smoking was statistically significantly associated with other harmful health behaviours. The snuffers reported more snacking than the non-smokers, but were most frequent brushers. The result from the statistical modelling showed that smoking, low tooth brushing frequency, eating sweets and consuming energy drinks frequently were significantly associated with restorative treatment need. In this cross-sectional study, association between smoking and dental caries was distinct. The high rate of restorative treatment need among smokers may be explained by their poor health behaviours. Dietary habits of the snuffers seem harmful too, but are compensated by good tooth brushing frequency.