ESE position statement on root resorption.

This Position Statement on root resorption represents the consensus of an expert committee convened by the European Society of Endodontology (ESE). The statement is based on current clinical and scientific evidence as well as the expertise of the committee. The aim is to provide clinicians with authoritative information on the aetiology, histopathology, clinical presentation and recommendations for the management of root resorption. It is the intention of the committee to update this position statement at appropriate intervals as further evidence emerges.

The association between dental caries and physical activity, physical fitness, and background factors among Finnish male conscripts.

Studies on measured physical fitness and oral health are sparse. The aim of this study was to investigate the associations between self-reported physical activity and measured physical fitness and oral health of young men. The study population consisted of 13,564 Finnish male conscripts who had mandatory clinical oral examinations and physical fitness tests at the beginning of military service in 2011. Finally, around 10,800 conscripts had physical fitness test outcomes available and a total of 8552 conscripts answered a computer-based questionnaire on background factors. Decayed Tooth (DT) and Decayed, Missing, or Filled Tooth (DMFT) indices, outcomes of surveys and fitness tests were used in analyses by cross-tabulation and multivariable logistic regression model (odds ratios [OR] with 95% confidence interval [CI]) were calculated. Regularly exercising conscripts had a reduced need for dental restorative treatment than those reporting no physical activity (p < 0.0001). The proportion of participants with sound dentition (DT = 0) increased steadily with increasing physical activity (39.0-59.4%). Good measured physical fitness was a protective factor against increased dental restorative treatment need. A low prevalence of smoking and low use of alcohol and energy drinks were associated with frequent exercise, whereas consumption of sport drinks and snuff use were common among those who exercised frequently. Good measured physical fitness and self-reported physical activity are associated with reduced caries burden. There is a need for information about the harms of tobacco products and the benefits of a healthy diet, even for the increased energy needs of the physically active.

Incorporation of dimethyl sulfoxide into experimental hydrophilic and hydrophobic adhesive resins: evaluation of cytotoxic activities.

This study evaluated the cytotoxicity of methacrylate-based resins containing dimethyl sulfoxide (DMSO). DMSO was incorporated into hydrophobic (R2) and hydrophilic (R5) resins at weight concentrations of 0, 0.01, 0.1, 1, 5, or 10 w/w %. Resin discs (n = 10/group) were prepared. Human gingival fibroblasts (HGF-1) were exposed to resin eluates for 24 h. Furthermore, dentin barrier test was performed using 3-D cultures of odontoblast-like cells (SV40 transfected pulp derived cells) with dentin slices of 400 µm thickness (n = 8). After acid etching of dentin, DMSO-modified resins were applied into the cavity part of the device and light-cured for 20 s. Cell viability (%) was assessed by MTT and analyzed spectrometrically. Data were analyzed by ANOVA and Tukey test (α = 0.05). Resin eluates showed statistically significantly lower % cell viability for all neat and DMSO-modified resins than seen for the negative control. Moreover, DMSO-R5 eluates resulted in significantly lower % cell viability than DMSO-R2 emulates. The dentin barrier test showed that DMSO-R2 did not result in significantly lower % cell viability, whereas incorporation of 1-10 w/w % DMSO into R5 resulted in significantly lower % of cell viability. Incorporating DMSO into hydrophilic self-etching resins may increase cytotoxicity. The biocompatibility is not influenced by the addition of DMSO into hydrophobic resin.

Dentifrices or gels containing MMP inhibitors prevent dentine loss: in situ studies.

OBJECTIVES: Evaluate the effect of dentifrices or gels containing MMP inhibitors on dentine loss in situ. MATERIALS AND METHODS: Acrylic palatal appliances containing bovine dentine blocks were divided into two rows, corresponding to the groups erosion (ERO) and erosion associated with abrasion (ERO+ABR). For ERO, the appliances were immersed in a cola drink for 5 min, 4 times/day, while for ERO+ABR, the blocks were brushed for 15 sec with a dentifrice slurry after the second and third erosive challenges. Ten volunteers took part in study 1 (S1), where the dentifrices evaluated contained 1100 ppm fluoride as NaF, 0.61% green tea extract, or 0.012% chlorhexidine digluconate. Thirteen volunteers participated in study 2 (S2), in which the treatment was performed only once (1 min) with gels containing 400 µM EGCG (EGCG400), 0.012% chlorhexidine, 1 mM FeSO4, 1.23% F (NaF), placebo, or received no treatment. Dentine loss was analyzed by profilometry (µm). RESULTS: Regarding S1, ERO+ABR induced significantly higher dentine loss compared with ERO and all dentifrices tested led to significantly lower dentine loss when compared with placebo. For S2, regardless of the conditions or times of evaluation, gels containing EGCG, CHX, or FeSO4 led to significantly less wear compared with the other groups. CONCLUSION: Both dentifrices and gels containing MMP inhibitors significantly reduced dentine loss. CLINICAL RELEVANCE: Dentifrices and gels containing MMP inhibitors are able to increase the protection against dentine wear, although gels have a better effect when compared with fluoride gel, lasting up to 10 days after a single application.

Survival of primary molars with pulpotomy interventions: public oral health practice-based study in Helsinki.

OBJECTIVES: To assess long-term survival of pulpotomized primary molars and factors related to the survival of the teeth. MATERIALS AND METHODS: This retrospective longitudinal study was based on electronic dental health records of children who attended public health service. Eligible children were <12 years and had a pulpotomy procedure code in their dental treatment history. Data were obtained in the period between 2002 and 2016. Chi-squared test, t-test, and one-way ANOVA were used to assess for statistical differences. Kaplan-Meier analyses were performed to create survival estimates, and the log-rank test was performed to compare differences in survival distributions. A multivariate Cox regression was conducted, and hazard ratios were calculated to estimate the hazard rate for failure. RESULTS: Of interventions, 40% were registered in children 3-6 years of age; 56% were boys. Mean estimated survival of such molars was 82 months (SEM = 0.6) and differed by dental operator's work setting and choice of restorative materials used after pulpotomy intervention. Using a stainless steel crown (SSC) to restore pulp-intervened primary molars had the strongest effect on survival (111 months with SEM = 1.8), followed by if the intervention was performed by a specialist or specializing dentist in paediatric dentistry (99 months with SEM = 2.6). CONCLUSIONS: The estimated survival time of pulpotomized primary molars is affected by dental operator-related factors, which should be considered in management of extensively carious primary molars of paediatric patients, both at the clinical and organizational decision-making levels. An increased focus on the use of SSC is recommended to be in the learning objectives of dental education programs.

Modeling enamel matrix secretion in mammalian teeth.

The most mineralized tissue of the mammalian body is tooth enamel. Especially in species with thick enamel, three-dimensional (3D) tomography data has shown that the distribution of enamel varies across the occlusal surface of the tooth crown. Differences in enamel thickness among species and within the tooth crown have been used to examine taxonomic affiliations, life history, and functional properties of teeth. Before becoming fully mineralized, enamel matrix is secreted on the top of a dentine template, and it remains to be explored how matrix thickness is spatially regulated. To provide a predictive framework to examine enamel distribution, we introduce a computational model of enamel matrix secretion that maps the dentine topography to the enamel surface topography. Starting from empirical enamel-dentine junctions, enamel matrix deposition is modeled as a diffusion-limited free boundary problem. Using laboratory microCT and synchrotron tomographic data of pig molars that have markedly different dentine and enamel surface topographies, we show how diffusion-limited matrix deposition accounts for both the process of matrix secretion and the final enamel distribution. Simulations reveal how concave and convex dentine features have distinct effects on enamel surface, thereby explaining why the enamel surface is not a straightforward extrapolation of the dentine template. Human and orangutan molar simulations show that even subtle variation in dentine topography can be mapped to the enamel surface features. Mechanistic models of extracellular matrix deposition can be used to predict occlusal morphologies of teeth.

Consumption of snacks and dental caries among Finnish young men: a cross-sectional epidemiological study.

The aim of this study was to investigate the frequency of consumption of snack products, as well as the association between snacking and restorative treatment need, and associated factors among a healthy Finnish male population. Approximately 8500 conscripts answered a computer-based questionnaire covering their snacking habits and other health behaviours. Restorative treatment need and history (DT, DMFT) were examined by trained and calibrated dentists. Cross-tabulations were used to investigate the associations between snacking habits and the other researched variables, and logistic regression analyses (odds ratio and 95% confidence interval) were used to investigate the variables influencing the restorative treatment need. In the present study, almost one-third of the study group consumed snack products daily, most often fizzy and energy drinks. Only 10% had received a diet counselling. The most common situations involving snacking were at the cinema and while playing computer games. According to Pearson's Chi square test, snacking was associated with smoking and snuffing and infrequent tooth brushing (p < 0.001). According to the regression analyses, daily snacking, smoking, and doing exercise daily increased the odds for restorative treatment need whereas higher education level and tooth brushing twice or more often per day decreased the odds for restorative treatment need. It can be concluded that daily snacking is common among Finnish young men and is associated with restorative treatment need. Snacking is also associated with other harmful oral and general health habits. Individual dietary counselling should be routinely offered to everybody in dental clinics.

Estimating molar-incisor-hypomineralization among 8-year-olds based on 15-year public oral health practice-based data.

Background: A wide range in the prevalence of molar-incisor-hypomineralization (MIH) has been reported. Population-based studies are recommended. However, such studies are expensive and time-consuming.Objectives: To estimate the magnitude of MIH condition among 8-year-olds based on routine oral health examinations and to associate first permanent molar (FPM) affection with that of other permanent teeth over time.Materials and methods: This retrospective study, with cross-sectional and longitudinal components, was based on electronic oral health records; all 8-year-olds examined between 2002 and 2016 were included.Results: The average estimated prevalence of MIH was 8.3%; yearly range was 4.8-15.9%. The mean number of affected teeth was 1.4; 62% had one affected tooth. One-surface defects were the most frequent (66%). Asymmetric distribution of affected teeth was observed. In follow-up, 10.7%, 8.4%, and 11.2% had at least one affected permanent canine, premolar, or second permanent molar, respectively. The proportion of children with other MIH-affected permanent teeth was higher in the group with ≥2 MIH-affected teeth than in group with one affected FPM at the age of 8.Conclusions: The average prevalence of MIH was comparable to that reported elsewhere. The number of MIH-affected teeth at early mixed dentition predicts the affection of other permanent teeth over time, mainly that of permanent canines. Further screening of children with MIH is recommended to improve individually tailored early preventive and restorative dental care.

Inhibition of dentin matrix-bound cysteine cathepsins by potassium fluoride.

Matrix metalloproteinases (MMPs) and cysteine cathepsins (CCs) can break down unprotected type I collagen fibrils in dentin matrix. This study investigated the use of potassium fluoride (KF) as a potential inhibitor of MMPs and CCs in dentin. Demineralized dentin beams were divided into groups (n = 10 in each group) and incubated in artificial saliva (AS, control), either alone or with one of seven concentrations of KF (6-238 mM fluoride) for 1, 7, and 21 d. After 21 d, all groups were further aged in AS for 6 months. Total MMP activity was screened using the colorimetric MMP assay. The activities of MMP-2 and MMP-9 were investigated using gelatin zymography. At the end of each incubation, changes in loss of dry mass and CC-mediated or total dissolution of collagen peptides were measured via precision weighing, C-terminal crosslinked telopeptide of type I collagen (CTX), and hydroxyproline (HYP) assays. The beams were examined using scanning electron microscopy. After 21 d, total MMP activities, dry mass loss, and CTX release for the groups exposed to 179 and 238 mM fluoride were significantly lower compared with the control group. After 6 months, all groups showed similar total MMP activity, dry mass loss, and HYP release, and CTX levels were significantly lower when the fluoride concentration was ≥24 mM. Calcium fluoride (CaF2 )-like precipitates were observed over the beams. In summary, KF significantly inhibited the catalytic activity of dentin matrix-bound CCs but did not seem to be effective for MMP-mediated activity.

Association of dietary habits with restorative dental treatment need and BMI among Finnish conscripts: a cross-sectional epidemiological study.

OBJECTIVE: Processed foods and fatty, sugary snacking products, such as fizzy drinks and desserts, have become more popular, causing a desire to replace meals with snacks worldwide. High-sugar and fat-rich food components have been reported to be associated with increased level of dental caries as well as underweight and overweight. The aim of the present cross-sectional population-based study was to analyse the eating behaviours of young, healthy Finnish males in association with oral health and BMI, considering self-reported and residential background factors. DESIGN: Cross-sectional study. SETTING: Finnish Defence Forces, Finland. PARTICIPANTS: The used clinical data were gathered from 13 564 Finnish conscripts born in the beginning of the 1990s through clinical check-ups. In addition, about 8700 of the conscripts answered a computer-assisted questionnaire ('Oral Health of the Conscripts 2011' data) about their background information and health habits. RESULTS: There was distinct variation in dietary patterns. Eating breakfast, regular physical exercise and daily tooth brushing all decreased the odds for restorative dental treatment need (decayed teeth), whereas smoking and drinking fizzy drinks for quenching thirst increased it. Eating breakfast and dinner were each associated with lower BMI, but smoking increased the odds for higher BMI (≥25 kg/m2). CONCLUSIONS: Regular, proper meals and especially eating breakfast decreased the odds for both dental caries and high BMI (≥25 kg/m2).

Genome-Wide Association Study of Erosive Tooth Wear in a Finnish Cohort.

Erosive tooth wear is defined as irreversible loss of dental tissues due to intrinsic or extrinsic acids, exacerbated by mechanical forces. Recent studies have suggested a higher prevalence of erosive tooth wear in males, as well as a genetic contribution to susceptibility to erosive tooth wear. Our aim was to examine erosive tooth wear by performing a genome-wide association study (GWAS) in a sample of the Northern Finland Birth Cohort 1966 (n = 1,962). Erosive tooth wear was assessed clinically using the basic erosive wear examination. A GWAS was performed for the whole sample as well as separately for males and females. We identified one genome-wide significant signal (rs11681214) in the GWAS of the whole sample near the genes PXDN and MYT1L. When the sample was stratified by sex, the strongest genome-wide significant signals were observed in or near the genes FGFR1, C8orf86, CDH4, SCD5, F2R, and ING1. Additionally, multiple suggestive association signals were detected in all GWASs performed. Many of the signals were in or near the genes putatively related to oral environment or tooth development, and some were near the regions considered to be associated with dental caries, such as 2p24, 4q21, and 13q33. Replications of these associations in other samples, as well as experimental studies to determine the biological functions of associated genetic variants, are needed.

The types and management of dental trauma during military service in Finland.

BACKGROUND/AIMS: All Finnish males must attend compulsory military service that lasts from 6 months to 1 year. About 25 000 males (approximately 80% of each age cohort) and 400 volunteer females complete the service annually. The aim of the study was to investigate the types of dental trauma occurring among Finnish conscripts during their military service. The article also focused on how dental trauma is treated in the Finnish Defence Forces. MATERIAL AND METHODS: All dental records in the Defence Forces' patient register concerning dental trauma during the years 2011 and 2012 were analysed by tooth number, treatment procedures and number of visits. RESULTS: According to the patient register, 361 conscripts suffered an oral trauma during their military service; thus, the average annual incidence was 7.2 trauma per 1000 conscripts. A total of 483 teeth were traumatized in the 2-year period. The most frequently traumatized teeth were the maxillary central incisors (61%), and the most common findings were enamel or enamel-dentin fractures (63% of all findings). Severe trauma was not common, and the most severe ones occurred during off-duty hours. The most common treatment was direct filling (n = 189 patients). Only 53 patients had soft tissue injuries (bruises, wounds). Among patients with dental trauma, the mean number of visits to the Defence Forces' dental clinic was 1.9. Great variation exists in recording findings concerning dental and oral trauma. CONCLUSION: Minor trauma is common. In all cases, recording trauma and treatments should be performed carefully.

Survival of extensive restorations in primary molars: 15-year practice-based study.

BACKGROUND: Caries decline in the western world is accompanied by strong polarization among children; 8% of Finnish 5-year-olds having 76% of untreated caries. This high caries risk group needs preventive and restorative strategies. AIM: To explore survival of extensive restorations in primary molars. DESIGN: This study was based on health records from 2002 to 2016 of children under 18 years. RESULTS: Of severely affected primary molars (n = 1061), 41% were restored with preformed metal crowns (PMCs), 38% with glass-ionomer cement (GIC)/polyacid-modified resin composite (PAMRC)/resin-modified GIC (RMGIC), and 21% with resin composites (RC). Younger children (3-8) received 97% of the PMCs and 86% of GIC/PAMRC/RMGIC; older ones (≥9) 91% of the RC restorations. Neither amalgam nor indirect restorations were registered. General dentists (GDs) engaged in primary care restored with GIC/PAMRC/RMGIC (52%) or RC (48%). GDs in general anesthesia care service placed 66% and specializing/specialized dentists 31% of PMCs. PMCs had lower failure rate (1.4% vs 3.0%) than GIC/PAMRC/RMGIC (P = 0.001). Choosing PMCs reduced patient visits compared to other restorations (P < 0.001). CONCLUSIONS: Severely affected primary molars of children at high caries risk are better managed, using PMCs to optimize the resources in public oral health services.

Effect of pH on dentin protease inactivation by carbodiimide.

A water-soluble crosslinking agent, 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC), has been used as a pretreatment of acid-etched dentin to inactivate matrix-bound endogenous dentin proteases. The aim of this study was to evaluate the effect of pH on the inactivation capacity of EDC. Demineralized dentin beams (1 × 2 × 6 mm) were divided into six groups (n = 8 per group). Then, EDC (0.3 M) was solubilized in distilled water with pH of 2, 4, 6, 7, 9, or 11. Control EDC was solubilized in 0.1 M 2-(N-morpholino) ethanesulfonic acid (MES) buffer and its pH was adjusted to 6. The dentin beams were pretreated for 1 min with EDC at each pH or with EDC in MES buffer at pH 6.0 and then incubated in 1 ml of simulated body fluid (pH 7.2) for 1, 3, 7, or 14 d. Untreated beams served as controls. At each study time-point, the dry mass of dentin beams was assessed and the incubation media were analyzed for carboxyterminal telopeptide of type-I collagen (ICTP) and C-terminal telopeptide of type I collagen (CTX) using specific ELISAs. Data were subjected to repeat-measures anova. The results of the study indicated that specimens pretreated with EDC in MES buffer showed the lowest collagen degradation in terms of mass loss and release of telopeptides, while specimens pretreated in alkaline media showed the highest collagen degradation. This study indicates that the pH of the EDC solution plays an important role in the stability of dentin protease inactivation.

Postradiation Matrix Metalloproteinase-20 Expression and Its Impact on Dental Micromorphology and Radiation-Related Caries.

Recent evidence suggests that head-and-neck radiotherapy (HNRT) increases active forms of matrix metalloproteinase-20 (MMP-20) in human tooth crowns, degrading the dentin-enamel junction (DEJ) and leading to enamel delamination, which is a pivotal step in the formation of radiation-related caries (RRC). Additional participation of enzymatic degradation of organic matrix components in caries progression was attributed to MMP-20 in dentin. Therefore, the current study tested the hypothesis that MMP-20 is overexpressed in the DEJ, dentin-pulp complex components, and carious dentin of post-HNRT patients, leading to detectable micromorphological changes to the enamel and dentin. Thirty-six teeth were studied, including 19 post-HNRT specimens and 17 nonirradiated controls. Optical light microscopy was used to investigate the micromorphological components of the DEJ, dentin-pulp complex components, and carious dentin. The samples were divided into 2 subgroups: nondemineralized ground sections (n = 20) and demineralized histological sections (n = 16). In addition, immunohistochemical analysis using the immunoperoxidase technique was conducted to semiquantitatively assess MMP-20 expression in the DEJ, dentin-pulp complex components, and carious dentin. No apparent damage to the DEJ microstructure or other dentin-pulp complex components was observed and no statistically significant differences were detected in MMP-20 expression (p > 0.05) between the irradiated and control groups. This study rejected the hypothesis that MMP-20 is overexpressed in the DEJ, dentin-pulp complex components, and carious dentin of post-HNRT patients, leading to detectable micromorphological changes. Hence, direct effects of radiation may not be regarded as an independent factor to explain aggressive clinical patterns of RRC.

Profiling of smokers and snuffers among young Finnish men - cross-sectional epidemiological study.

OBJECTIVE: The purpose of this study was to get new information from several sources about the background factors of Finnish smokers, snuffers, and dual users. Profiles of young smokers and snuffers were investigated in association with restorative treatment need, oral hygiene, eating habits, physical activity, body mass index (BMI), psychological and socioeconomic factors. MATERIAL AND METHODS: The study group comprised 3420 conscripts. The data were collected from four different sources: a health examination including an oral health screening, a computer-based questionnaire for investigating individual background factors, a psychological test assessing cognitive skills, and the Cooper test. Statistical analyses comprised cross tabulation and binary logistic regression modelling. RESULTS: The odds for smoking were the greatest among those who had DT (Decayed teeth) > 0, used energy drinks or alcohol regularly, or whose parents were divorced. A score of ≥2900 m in the Cooper test, a higher physical exercise level, a higher own education level, and using sports drinks decreased the odds for smoking. The odds for snuffing were higher among those who ran >2500 m in the Cooper test, had a BMI of ≥25, used sports/energy drinks, or exercised regularly, and lower among those who achieved good results in the cognitive test. Using energy/sports drinks or alcohol was positively and a higher education level was negatively associated with dual use. CONCLUSIONS: Along with increasing prevalence of snuffing, heterogeneity is likely among snuffers. Good cognitive skills may prevent from smoking and snuffing.

NaF Inhibits Matrix-Bound Cathepsin-Mediated Dentin Matrix Degradation.

Matrix metalloproteinases (MMPs) and cysteine cathepsins (CCs) degrade the collagen fibrils of demineralized dentin. Sodium fluoride (NaF) has previously been shown to inhibit recombinant MMP-2 and MMP-9. This study aimed to evaluate the efficacy of NaF on the inhibition of dentin-bound MMPs and CCs. Dentin beams were completely demineralized in 10% phosphoric acid. The baseline total MMP activity and dry masses were measured. Beams were assigned to test groups based on similar MMP activity and dry mass (n = 10/group), and incubated in artificial saliva (control) or artificial saliva with NaF containing 6-238 mM fluoride for 1, 7 and 21 days. The dry mass loss and MMP activities were reassessed at each time point. The proteolytic activity was screened by gelatin zymography. ICTP and CTX released to the incubation medium were analyzed as indices of MMP and cathepsin K activity, respectively. The beams were examined under scanning electron microscopy. All NaF doses reduced the dry mass loss after 21 days (p < 0.05). NaF inhibition of the total MMP activity ranged between 5 and 80%. In gelatin zymography, the bands of MMP-2 and MMP-9 became less prominent with increasing NaF levels. NaF did not decrease the released ICTP (p > 0.05). Less CTX release was detected with F ≥179 mM (p < 0.05). CaF2-like minerals were observed on the beams. High levels of NaF may slow the degradation of the dentin matrix due to the inhibition of cathepsin K. Fluoride does not seem effective in the direct inhibition of proteolysis by dentin matrix-bound MMPs.

Influence of Intrinsic Factors on Erosive Tooth Wear in a Large-Scale Epidemiological Study.

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.

Association of erosive tooth wear and dental caries in Northern Finland Birth Cohort 1966 - an epidemiological cross-sectional study.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Matrix metalloproteinases and other matrix proteinases in relation to cariology: the era of 'dentin degradomics'.

Dentin organic matrix, with type I collagen as the main component, is exposed after demineralization in dentinal caries, erosion or acidic conditioning during adhesive composite restorative treatment. This exposed matrix is prone to slow hydrolytic degradation by host collagenolytic enzymes, matrix metalloproteinases (MMPs) and cysteine cathepsins. Here we review the recent findings demonstrating that inhibition of salivary or dentin endogenous collagenolytic enzymes may provide preventive means against progression of caries or erosion, just as they have been shown to retain the integrity and improve the longevity of resin composite filling bonding to dentin. This paper also presents the case that the organic matrix in caries-affected dentin may not be preserved as intact as previously considered. In partially demineralized dentin, MMPs and cysteine cathepsins with the ability to cleave off the terminal non-helical ends of collagen molecules (telopeptides) may lead to the gradual loss of intramolecular gap areas. This would seriously compromise the matrix ability for intrafibrillar remineralization, which is considered essential in restoring the dentin's mechanical properties. More detailed data of the enzymes responsible and their detailed function in dentin-destructive conditions may not only help to find new and better preventive means, but better preservation of demineralized dentin collagenous matrix may also facilitate true biological remineralization for the better restoration of tooth structural and mechanical integrity and mechanical properties.