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The aim of this study was to assess the temporal evolution of external cervical resorption (ECR) defects using a volumetric quantification method.Cone-beam computed tomographic (CBCT) images of patients diagnosed with ECR who chose not to receive treatment and attended recalls were collected. ECR defects were segmented in CBCT images at baseline and recall, and their volumes were quantified. The volumetric ratio of resorption defects/teeth was calculated. Three-dimensional classification of defects at baseline and recall and the prevalence of root surface perforations ≥1 mm were determined. The Wilcoxon matched pairs signed rank test, chi-square test, and linear regression models were used to analyze the data.Fifteen patients with 20 teeth diagnosed with ECR and an average recall time of 21 months were included. Nine (45%) teeth showed a change in 3-dimensional classification at recall. The volume of resorption defects (P = .0001) and the volumetric ratio of resorption defects/teeth (P = .0001) increased over time. The prevalence of root surface perforations ≥1 mm was higher at recall (n = 17, 85%) compared with baseline (n = 9, 45%) (P = .008). Linear regression models showed significant associations between the resorption defect volume at recall compared with baseline (P .0001; 95% confidence interval, 0.053-0.081) and the volumetric ratio of resorption defects/teeth at recall compared with baseline (P .0001; 95% confidence interval, 0.205-0.356). There was no association between the volume of resorption defects at recall with the length of the recall period, sex, or age (P .05).When left untreated, ECR defects can increase in size and develop more root surface perforations. ECR has a dynamic nature, and its volumetric increase over time does not result from uniform/linear expansion of the defects.

A rare case of extensive multiple idiopathic cervical root resorption with potential genetic predisposition was presented. A heathy 19-year-old Chinese male with no contributory medical or family/social history complained of pain during mastication that lasted for several months. Oral examination identified 7 missing teeth and external cervical root resorption involving 9 teeth. Comparison of orthopantomograms taken in May 2021 and February 2022 identified that cervical root resorption occurred in 22 teeth. Resorption commenced at the cementoenamel junction and progressed rapidly over the 9-month period. Laboratory test results were within normal limits. Trio-based whole-exome sequencing showed a missense mutation c.5630 C T in the filamin A (FLNA) gene at chromosome X of the subject. This is suggestive of the possibility of sex-linked recessive inheritance. This is the first study to report FLNA mutation in human subjects with cervical root resorption involving multiple teeth.

Objective. This study investigated the effects of flowable resin composites (FCR) on the restoration of noncarious cervical lesions (NCCL) and their impact on periodontal tissues. Materials and Methods. 30 periodontally healthy patients were assigned into three groups randomly; group VF: self-adhering FCR, group NF: fluoride-releasing FCR, and group SF: microhybrid FCR. Gingival crevicular fluid (GCF) volume levels of osteoprotegerin (OPG), immunoglobulins (IgA, IgM), and interleukins (IL-1, IL-1β, and IL-10) in GCF were analyzed with ELISA tests. Clinical success rates were evaluated using USPHS criteria during the 12-month follow-up. Results. The GCF volume was increased mostly in group SF ( 1.34 ± 0.09 μ l ). While the titer of interleukin was increased in all groups, higher increases were observed in IL-1 and IL-1β in group NF (170.78 pg/ml and 39.35 pg/ml). Increased IL-10 was observed in group VF ( 14.33 ± 0.85 pg / ml ). IgA levels varied partially among all groups ( p > 0.05 ), and even IgM levels were elevated immediately after the restoration process but returned to normal on the 28th day ( p < 0.05 ). Group NF failed in most of the USPHS criteria, while the material group VF and group SF presented acceptable results except in the marginal adaptation criterion ( p < 0.05 ). Conclusions. Clinical efficacy of self-adhering FCR was found the best for restoration of NCCL while fluoride-releasing FCR stimulated the periodontal response and had negative effects on GCF volume, cytokine, and immunoglobulin levels.

To assess long-term external cervical resorption (ECR) treatment outcomes in relation to both local and treatment-related determinants.Information was available for 76 patients (98 teeth) who were diagnosed with ECR during the period from 2008 to 2018 at the University of British Columbia graduate endodontics clinic. The ECR patients were followed up, and a clinical and radiographic examination was conducted. Chi-square test compared failure rates amongst different subgroups. The survival analysis was used to evaluate the overall ECR survival/failure rates in relation to several local and treatment-related determinants.Overall, 67 patients (89 teeth) were followed up. The mean follow-up time was 3.9 years, and the minimum was 1 year. Twenty-four teeth failed (19 extracted, 5 not functional), and the overall probability of failure was 50.0% 8 years after the diagnosis. Significant (p .05) local ECR determinants were tooth location and the Heithersay classification, and treatment-related determinants were root canal treatment (RCT) and the ECR repair combined with RCT. Treatment outcomes for Heithersay class 1 and 2 cases were better than for class 3 and 4 cases.Higher failure rates were associated with posterior tooth location and higher Heithersay class, whilst RCT and ECR repair combined with RCT were associated with lower failure rates.

SUMMARYAimTo evaluate and compare the effects of both manual and ultrasonic scaling on surface roughness of four different base materials, used for elevating dentin/cementum gingival margins of proximal cavities.Methods and MaterialsEighty human upper molars with compound Class II mesial cavities, with gingival margins 1 mm below the cemento–enamel junction (CEJ), were divided into four different groups according to the type of the base material used; resin-modified glass ionomer (RMGI), glass hybrid (HV-GIC), flowable bulk-fill resin composite (Bulk Flow) and bioactive ionic resin (Activa). This was followed by completing the restorations with the same resin composite. All materials were used according to the manufacturers’ instructions. All groups were further subdivided into two subgroups according to the scaling technique: manual (hand) or ultrasonic. All restorative and scaling procedures were performed after fixation of specimens with acrylic beside neighboring teeth to simulate natural contact. The mean surface roughness (Ra, μm) of all specimens was measured quantitatively and qualitatively by a three-dimensional (3D) surface analyzer system at two stages; (1) after thermal cycling for 5000 cycles without scaling and (2) after scaling. Data were statistically analyzed using analysis of variance (ANOVA), Tukey post hoc tests, and paired sample t-tests (at α=0.05).ResultsFor baseline readings, the Bulk Flow group had the lowest Ra values, while HV-GIC group had the highest. RMGI and Activa groups had no statistical significant difference between their Ra values (p>0.05). For post scaling readings, hand scaling had significantly lower Ra values than ultrasonic scaling in all the material groups (p0.05)ConclusionBulk Flow had the smoothest surfaces when cured against a matrix band compared with the other tested base materials. When hand and ultrasonic scaling methods were compared, the latter technique had more detrimental effect on the surface texture of the four tested base materials.

OBJECTIVES: This study aimed to assess the enamel and dentin marginal microleakage and dentin microtensile bond strength (μTBS) of ACTIVA BioACTIVE Restorative with and without a bonding agent compared with conventional restorative materials. MATERIAL AND METHODS: For enamel and dentin microleakage, Class II boxes were prepared in the mesial (1 mm under the cementoenamel junction) and distal (1 mm above the cementoenamel junction) surfaces of 90 extracted human third molars. The teeth were randomly divided into five groups (n = 18): Group Z (G‐Premio Bond + Filtek Z250 XT), Group X (G‐Premio Bond + X‐tra fil bulk‐fill), Group AA (G‐Premio Bond + Activa Bioactive restorative), Group A (Activa Bioactive restorative), and Group G (dentin conditioner + Fuji II LC Improve). The teeth were thermocycled, and their microleakage was quantified using the dye penetration test under a stereomicroscope. For dentin μTBS measurement, 12 specimens were fabricated in metal molds (1 × 1 × 12 mm³) for each group mentioned above, and a universal testing machine measured their μTBS. Data were analyzed using one‐way analysis of variance (ANOVA), the Kruskal–Wallis test, and multiple comparisons tests. RESULTS: Significant differences were noted among the groups in marginal microleakage and μTBS (p

Item does not contain fulltext AIM: To investigate the prevalence of non-carious cervical lesions (NCCLs) and their association with individual and tooth-related factors in adults from the 1982 Pelotas Birth Cohort. MATERIALS AND METHODS: Participants were interviewed and clinically examined at the age of 31. NCCL was defined as loss of dental tissue without bacterial involvement in the cervical region. Independent variables were the socioeconomic, demographic, behavioural, and clinical characteristics. Associations were tested using a multilevel Poisson regression model. RESULTS: Five-hundred and thirty-nine participants were clinically examined, with a 26% prevalence of NCCLs, which were more prevalent in the maxilla (56.5%) and in premolars (72.9%). In the multilevel analysis, women presented lower prevalence than men [prevalence ratio (PR) 0.59 (0.48-0.73)]; those who reported smoking at both 22 and 30 years of age had more NCCLs than those who never smoked [PR 1.65 (1.31-2.07)]; and high-frequency brushers presented higher prevalence than low-frequency brushers [PR 1.26 (1.03-1.55)]. Gingival recession increased 10 times the prevalence of NCCLs [PR 10.03 (8.15-12.35)], while the presence of periodontal pockets (≥4 mm) reduced the prevalence of NCCLs [PR 0.43 (0.28-0.66)]. CONCLUSIONS: NCCLs were more prevalent in males, smokers, and those with higher frequency of toothbrushing. While the presence of periodontal pockets was associated with a lower prevalence of NCCLs, gingival recession was a strong clinical indicator for the presence of NCCLs.

SUMMARY Objectives To evaluate the 5-year clinical performance of two-step etch-and-rinse adhesives in noncarious cervical lesions (NCCL). Methods and Materials The sample comprised 35 adults with at least two similar-sized NCCL. Seventy restorations were placed, according to one of the following groups: Adper Single Bond 2 (SB) and Ambar (AM). The restorations were placed incrementally using a resin composite (Opallis). The restorations were evaluated at baseline and after 6 and 18 months and 5 years using some items of the FDI criteria. The differences in the ratings of the two materials after 6 months, 18 months, and 5 years were performed with Friedman repeated measures ANOVA by rank and McNemar test for significance in each pair (α=0.05). Results Five patients did not attend the 60-month recall. No significant differences were observed between the materials for any criteria evaluated. Twenty-one restorations failed (12 for SB and 9 for AM) after 60 months. Thus, the retention rate for SB at 60 months were 55.6% for SB and 71% for AM (p=0.32). After 60 months, 12 restorations (6 for SB and 6 AM) showed some loss of marginal adaptation (p=1.0). Slight marginal discoloration was observed in 10 restorations (6 for SB and 4 AM; p=0.91). Five restorations (2 for SB and 3 for AM) showed recurrences of caries (p=1.0). Conclusions Both two-step etch-and-rinse adhesives—Adper Single Bond 2, a polyalkenoic acid-containing adhesive, and Ambar, a 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing adhesive—showed acceptable clinical performance after 60 months.

This article reports on published literature for causative factors of cervical dentin hypersensitivity and noncarious cervical lesions. The author conducted an exhaustive literary review of both conditions to examine etiologic co-factors involved for these dental findings. Previous literature found that these two conditions arise from combinations of dental stress distant from occlusal contacts, biocorrosion, and possibly friction. It is impossible to separate these three factors for the modern dentate human due to masticatory function and tooth contact when swallowing. The author concludes that in vivo study is needed to clarify the roles that etiologic factors play in the development of this type of dental pain and/or noncarious lesions. The clinical significance of this review is that a dental and medical history and active etiologic factors need to be uncovered for cervical dentin hypersensitivity with resulting noncarious cervical lesions. The successful clinician needs to determine causative factors, if possible, prior to treatment.

To evaluate the 24-month clinical performance of a "no wait" universal adhesive with different application modes in comparison with an etch-and-rinsew and two-step self-etch adhesive in non-carious cervical lesions (NCCLs).A total of 234 non-carious cervical lesions in 34 patients were restored following 5 different adhesive approaches: 1. Clearfil Universal Bond Quick, self-etch mode (CUQ-SE); 2. Clearfil Universal Bond Quick, selective etch mode (CUQ-SLE); 3. Clearfil Universal Bond Quick, etch-and-rinse mode (CUQ-ER); 4. Clearfil SE Bond (self-etch adhesive) (CSEB); 5. Tetric N-Bond Universal, etch-and-rinse mode (TBU-ER). All NCCLs were restored with a nanohybrid composite (Tetric N-Ceram). The restorations were evaluated at baseline, 6, 12, and 24months of clinical service regarding retention, marginal adaptation, marginal discoloration, secondary caries, post-operative sensitivity, color match, surface texture using modified United States Public Health Service (USPHS) criteria.The patient recall rate at 24 months was 73.5%. Eleven restorations, 6 of the CUQ-SE group, 4 of the CSEB group and 1 of the TBU-ER group, were clinically unacceptable due to retention loss. Regarding marginal adaptation and discoloration, CUQ-SE and CSEB groups exhibited higher bravo scores than other groups after 24 months (p0.05). At the end of 24-month examinations, no significant differences were detected among the groups regarding secondary caries, post-operative sensitivity, color match and surface texture.The clinical survival rates of the "no wait" universal adhesive at self-etch mode after 24 months were not acceptable. The "no wait" universal adhesive showed clinically acceptable performance in selective-etch and etch-and-rinse mode according to the evaluated USPHS criteria.

Gingival recession accounts for apical migration of the gingival margin, resulting in exposure of the cementoenamel junction and root surface, with exposure of the root surface linked to deteriorated esthetic appearance and increased dentinal hypersensitivity. Various surgical techniques have been used to correct labial gingival recession defects. The present study evaluated and compared the results of semilunar coronally positioned flap (SCPF) alone and in conjunction with free gingival graft (FGG) for the treatment of Miller Class I and II gingival recession defects in maxillary anterior teeth. A total of 20 bilateral Miller Class I and II gingival recession sites were included and randomly allocated (n = 10 sites/group) to either the semilunar coronally positioned flap technique alone (SCPF group; control) or with FGG (SCPF+FGG group; test). Longitudinal alterations in probing depth (PD), recession width (RW), recession height (RH), width of keratinized tissue (WKT), and clinical attachment level (CAL) were measured and analyzed for both groups at 1-, 3-, 6-, and 12-month follow-ups. Both groups saw a significant decrease in RH, RW, and CAL and a significant increase in WKT. No statistically significant difference was observed in the final root coverage outcome between both groups in terms of RH, RW, and CAL, but a significant increase in WKT was seen with SCPF+FGG. Both techniques demonstrated optimal results without significant differences in the final root coverage outcomes except for WKT, which had a statistically significant increase in the SCPF+FGG group.

Impacted mandibular third molars (M3M) are associated with the occurrence of distal caries on the adjacent mandibular second molars (DCM2M). In this study, we aimed to develop and validate five machine learning (ML) models designed to predict the occurrence of DCM2Ms due to the proximity with M3Ms and determine the relative importance of predictive variables for DCM2Ms that are important for clinical decision making. A total of 2642 mandibular second molars adjacent to M3Ms were analyzed and DCM2Ms were identified in 322 cases (12.2%). The models were trained using logistic regression, random forest, support vector machine, artificial neural network, and extreme gradient boosting ML methods and were subsequently validated using testing datasets. The performance of the ML models was significantly superior to that of single predictors. The area under the receiver operating characteristic curve of the machine learning models ranged from 0.88 to 0.89. Six features (sex, age, contact point at the cementoenamel junction, angulation of M3Ms, Winter's classification, and Pell and Gregory classification) were identified as relevant predictors. These prediction models could be used to detect patients at a high risk of developing DCM2M and ultimately contribute to caries prevention and treatment decision-making for impacted M3Ms.

External cervical resorption (ECR) refers to a pathological state in which resorption tissues penetrate into the dentin at the cervical aspect of the root. Despite being latent in its initial phase, ECR could cause severe damage to mineralized dental tissue and even involve the pulp if not given timely diagnosis and treatment. Nevertheless, the etiology of ECR is still poorly understood, which adds to the difficulty in early diagnosis. ECR has received growing attention in recent years due to the increasing number of clinical cases. Several potential predisposing factors have been recognized in cross-sectional studies as well as case reports. In the meantime, studies on histopathology and pathogenesis have shed light on possible mechanisms of ECR. This review aims to summarize the latest findings in the pathogenesis and potential predisposing factors of ECR, so as to provide pragmatic reference for clinical practice.

Aim of the current research is to establish and assess the microleakage in bulk-fill composite, nanohybrid ormocer-based resins, and nanofilled composite resin core build-up materials employing the dye-penetration technique.Sixty human mandibular first premolar teeth with a solitary root canal without dental caries were chosen for this research. Each specimen was subjected to decoronation of 2 mm from the cementoenamel junction (CEJ), following which the root canal treatment procedure was rendered complete. A space for the post was made for all the 60 samples. Following positioning of the post, specimens were allocated into one of the following three investigational groups (20 specimens in every group) on the basis of the core build-up materials used as group I: bulk-fill composites, group II: nanohybrid ormocer-based resins, and group III: nanofilled resin composites. Direct composite was used for core build-up and subjected to light-curing. Following this, the specimens were immersed in 1% methylene blue solution for 24 hours interval. Each section was evaluated for dye diffusion employing a stereomicroscope with software at a magnifying power of 40× and surface contact between dentin and base of the material was evaluated under scanning electron microscope.Nanohybrid ormocer-based composites exhibited the least microleakage at 1.12 ± 0.14, in pursuit by nanofilled composite resins at 1.79 ± 0.09, and finally the bulk-fill composites at 2.85 ± 0.11, amid the investigational groups studied. A statistically significant difference amid the three dissimilar cores buildup substances was found upon analysis of variance.Despite the study limitations, this research came to a conclusion that each of the three investigated core build-up substances exhibited microleakage. However, amid the three, nanohybrid ormocer-based composites depicted the lowest amount of microleakage in pursuit by the nanofilled resins and the bulk-fill composites.Core build-up is an important requirement as the remaining tooth substance following root canal treatment reduces and needs reinforcement with core build-up to sustain the tooth structure and provide resistance. A vital mandate for enduring efficiency of the restoration in the mouth is high-quality adhesive bond of these agents to cavity walls with diminished microleakage.

Background This study aimed to assess the distribution of non-carious cervical lesions (NCCLs) by tooth type, investigate the prevalence of NCCLs in patients undergoing orthodontic treatment, and identify the possible associated factors. Material and methods A total of 160 patients were enrolled in this retrospective study. Data on the following variables were collected from pre-and post-orthodontic treatment records: age, sex, Angle’s malocclusion, facial pattern, number of activation sessions, compensatory treatment, and retreatment. Frontal, right and left lateral intraoral photographs of each patient were evaluated to identify the presence or absence of NCCLs in each tooth and assess the distribution of NCCLs in the 3840 teeth from the enrolled patients. Furthermore, patients were classified as NCCLs present, irrespective of the number of NCCLs on the teeth or NCCL absent. Bivariate and multivariate Poisson regression analyses with robust variance were used to assess the association between the NCCLs and each independent variable. Prevalence ratio and 95% confidence intervals were calculated and p Results The prevalence of NCCLs before and after orthodontic treatment was 22.71% and 30.91%, respectively. Premolars were the most affected teeth, followed by the first molars, canines, and incisors. After statistical analysis, age was found to be the variable factor that influenced the prevalence ratio, with NCCL being the most prevalent when orthodontic treatment was performed in adulthood. Conclusions Premolars were most commonly affected by NCCLs. Furthermore, age seemed to contribute to the increased prevalence of NCCLs in adults undergoing orthodontic treatment.

The aim of this study was to investigate the impact of the incision type, with or without a coronally repositioning flap (CRF), on soft tissue healing and crestal bone remodeling after endodontic microsurgery (EMS).Clinical pictures and cone-beam computed tomography images from 47 patients (120 teeth) taken before surgery and at the follow-up appointment were included in this study. Clinical pictures were qualitatively evaluated by 2 endodontists for the gingival marginal level (GML) (recession, same position, or coronal root coverage), papillary height (same position/receded), and for presence/absence of scars for each tooth. Cone-beam computed tomography images were used to calculate the changes in the distance between the cementoenamel junction and the crestal bone level (CBL) between the preoperative and follow-up scans. Statistical analyses were performed to determine a correlation between patient-related factors (age, sex, tooth type, position, and presence/absence of a crown), incision techniques, and changes within the CBL.Gingival recession was more prevalent in mandibular teeth, molar teeth, and teeth that received intrasulcular or papilla-based incisions (P .05). Scar formation was affected by the flap design (P .05). CRF was the only technique resulting in coronal root coverage (P .05). There were no changes observed in the papillary height between the various flap designs. There was also no statistically significant difference in the crestal bone height between the preoperative and follow-up scan measurements (P .05).Soft tissue changes are evident after EMS and can be affected by the flap design selected, as well as the site being treated. Application of CRF can improve the position of GML after EMS. There are insignificant changes within the CBL at the facial aspect of the root after EMS.

The purpose of this in‐vivo study was to evaluate the clinical performance of restorations placed in non‐carious cervical lesions (NCCLs), using different cavity preparation designs, after 7.7 years. A total of 85 NCCLs with coronal margins in enamel and cervical margins in dentin were randomly assigned to the following treatment protocols: dentin surface cleaning, dentin surface roughening with round bur plus flowable composite, dentin surface roughening/cervical groove preparation with round bur, dentin surface roughening/cervical groove preparation with round bur plus flowable composite. After enamel beveling and selective enamel etching, the defects were restored with composite. The restorations were assessed by two independent, calibrated and blinded investigators, using modified USPHS criteria. At 7 years (7.7 (± 0.35)), a total of 64 restorations (75.3%) were available for follow‐up examination. The total retention rate, irrespective of the test groups, was 82.8%. Restorations placed without any preparation showed the highest loss rate (27.8%). Esthetic appearance, marginal adaptation, anatomic form and marginal discoloration did not differ significantly between the groups. Composites are long‐term stable materials for restoring NCCLs. Restorations placed without any dentin preparation (cavity cleaning only) showed the highest loss rate.

Clinical Relevance Non-carious cervical lesion restorations using a dual-cure universal adhesive in self-etch and etch-and-rinse mode showed satisfactory clinical performance after 18 months. SUMMARY Objectives: The objective of this multicenter, double-blind, split-mouth randomized clinical trial was to evaluate the clinical performance of a new dual-cure universal adhesive system (Futurabond U, Voco GmBH) when applied using different strategies over a period of 18 months. Methods and Materials: Fifty patients participated in this study. Two hundred non-carious cervical lesions were restored using the adhesive Futurabond U according to four adhesive strategies (n=50 per group): only self-etch (SEE), selective enamel etching + self-etch (SET), etch-and-rinse with dry dentin (ERDry), and etch-and-rinse with wet dentin (ERWet). After the adhesive application, cavities were restored using Admira Fusion composite resin. These restorations were evaluated according to FDI World Dental Federation criteria for the following characteristics: retention/fracture, marginal adaptation, marginal staining, postoperative sensitivity, and caries recurrence. Results: After 18 months, only four patients (12 months: one patient, n=4 restorations; and 18 months: three patients, n=12 restorations) were not evaluated. Fourteen restorations were lost after 18 months of clinical evaluation (four for SEE, three for SET, three for ERDry, and four for ERWet). The retention rates for 18 months (95% confidence interval) were 92% (81%–97%) for SEE, 94% (83%–97%) for SET, 94% (83%–97%) for ERDry, and 92% (81%–97%) for ERWet (p>0.05). Thirty-eight restorations were considered to have minor discrepancies in marginal adaptation at the 18-month recall (13 for SEE, 13 for SET, six for ERDry, and six for ERWet; p>0.05). Fourteen restorations were detected as a minor marginal discoloration at the 18-month recall (six for SEE, six for SET, one for ERDry, and one for ERWet; p>0.05). However, all were considered clinically acceptable. No restorations showed postoperative sensitivity or caries recurrence at the time. Conclusion: The clinical performance of the Futurabond U did not depend on the bonding strategy used, and it was considered reliable after 18 months of clinical evaluation, although more marginal discrepancy was observed in the self-etch group.

Objectives To compare the clinical performance of a universal adhesive in class V non-carious cervical lesions (NCCLs) using two surface treatment protocols (self-etch [SfE] vs selective-enamel-etch [SelE]). Material and methods Thirty-three adults, each with ≥2 NCCLs, received one resin composite restoration utilizing a SfE universal adhesive and another utilizing the adhesive and SelE with 37% phosphoric acid. Restorations were evaluated for sensitivity, retention, marginal discoloration, marginal adaptation, and clinical acceptability through 24 months using Cochran-Mantel-Haenszel tests for stratified, ordered categorical outcomes. Results Sixty-six restorations (35 SfE, 31 SelE; 27 volunteers) were evaluated at 24 months. There were no significant differences between SfE and SelE for sensitivity, retention, marginal adaptation, or clinical acceptability. One SfE restoration was lost. Marginal adaptation was significantly worse at 24 months than baseline for SelE (P = 0.01), but not for SfE. Marginal discoloration was significantly worse for SfE (P = 0.02), but not for SelE. Sensitivity improved from baseline to 24 months for both groups (SelE P = 0.004, SfE P = 0.002). Conclusions Twenty-four-month data indicated significantly reduced sensitivity for both groups, worse marginal discoloration for SfE, and worse marginal adaptation for SelE. No changes in retention or clinical acceptability were observed in either group. All retained restorations were clinically acceptable at 24 months. Clinical significance Both self-etch and selective enamel etch techniques with a universal adhesive produced clinically acceptable results in resin composite restorations for NCCLs over 2 years.

The aim of this present prospective study was to evaluate the outcomes of the multiple coronally advanced flap (MCAF) with a site-specific application of connective tissue graft (CTG) for the treatment of multiple gingival recession defects with or without the presence of noncarious cervical lesions (NCCLs). Analysis of periodontal conditions was performed in order to determine if the cementoenamel junction (CEJ) restorations could affect adequate plaque control as well as maintenance over time. A total of 93 gingival recessions were treated, 61% of which presented a NCCL restored with composite resin positioned 1 mm apical to the position of the anatomical CEJ. The surgical treatment involved MCAF+CTG for 54 sites and MCAF alone for 39 sites. At 12 months, complete root coverage (CRC) and periodontal parameters of restored and nonrestored teeth were assessed, and the differences between the two groups were not significant. It can be concluded that the proposed treatment modality does not produce a negative effect on periodontal condition and amount of CRC, thus resulting in a satisfactory esthetic result.

SUMMARY Purpose: The purpose was to perform a systematic review and meta-analysis based on the following research question: do tooth- and cavity-related aspects of noncarious cervical lesions (NCCLs) affect the retention of composite restorations? Methods: Randomized clinical trials (RCTs) that evaluated the retention rate of resin restorations in NCCLs were included for the identification and comparison of their characteristics. The search was conducted in PubMed and adapted for Scopus, Web of Science, Latin American and Caribbean Health Sciences Literature database (LILACS), Brazilian Library in Dentistry (BBO), Cochrane Library, and System for Information on Grey Literature in Europe (SIGLE) without restrictions until July 2018. Unpublished and ongoing trial registries were also searched. The Cochrane Collaboration tool was used for assessing risk of bias. The quality of the evidence was graded using the Grading of Recommendations: Assessment, Development and Evaluation. Using the random effects model, a meta-analysis was conducted for each aspect (arch distribution, tooth location, wear facets, dentin sclerosis, shape, size, depth, occluso-gingival distance, and margin location). Results: We retrieved 6738 articles. After removal of duplicates and nonrelevant articles, 24 RCTs remained. The anterior tooth location favored the retention rates of restoration of NCCLs (relative risk [RR], 1.08; 95% confidence interval [CI], 1.00-1.16). The presence of wear facets is a risk factor for the retention of restorations (RR, 0.91; 95% CI, 0.83-0.99). The evidence was moderate for arch distribution and low or very low for all other factors because of heterogeneity, imprecision, and inconsistency. Conclusion: The tooth location and the presence of wear facets can affect the retention of composite resins in NCCLs.

Clinical Relevance Using the deep margin elevation technique in preparations extending beyond the cemento-enamel junction appears to be beneficial in maintaining structural integrity of CAD/CAM-fabricated feldspathic ceramic inlays. SUMMARY Objective: To evaluate the effect of deep margin elevation on structural and marginal integrity of ceramic inlays. Methods and Materials: Forty extracted human third molars were collected and randomly separated into four groups (n=10/group). In group 1 (enamel margin group), the gingival margin was placed 1 mm supragingival to the cemento-enamel junction (CEJ). In group 2 (cementum margin group), the gingival margin was placed 2 mm below the CEJ. In group 3 (glass ionomer [GI] margin group), the gingival margin was placed 2 mm below the CEJ, and then the margin elevated with GI to the CEJ. In group 4 (resin-modified glass ionomer [RMGI] margin group), the gingival margin was placed 2 mm below the CEJ, and then the margin elevated with RMGI to the CEJ. Standardized ceramic class II inlays were fabricated with computer-aided design/computer-aided manufacturing and bonded to all teeth, and ceramic proximal box heights were measured. All teeth were subjected to 10,000 cycles of thermocycling (5°C/55°C) and then underwent 1,200,000 cycles of vertical chewing simulation at 50 N of force. Ceramic restorations and marginal integrity were assessed with a Hirox digital microscope. The Fisher exact test (two-tailed) with adjusted p-values (α=0.05) and logistic regression were used for statistical analysis. Results: The cementum margin group had a significantly higher ceramic fracture rate (90%) compared to other groups (10% in enamel margin and GI margin groups, p=0.007; 0% in RMGI group, p Conclusion: Deep marginal elevation resulted in decreased ceramic fracture when preparation margins were located below the CEJ. There was no difference found between margin elevation with GI or RMGI. Increased heights of ceramic proximal box may lead to an increased probability of ceramic fracture.

Identifying the accurate location of the greater palatine artery (GPA) can be challenging. The purpose of the present cadaver study was to determine the location of the GPA from the cementoenamel junction (CEJ) of the maxillary canine to second molar teeth and to define its relationship with the palatal vault height (PVH) in Caucasian cadavers. Sixty-six sections from fully or partially dentate cadavers were examined. The location of the GPA from the CEJ ranged from a minimum of 8.7 ± 2.1 mm at the canine to 14.5 ± 1.3 mm at the second molar. The minimum distance of the GPA to the CEJ in different PVH ranged from 6 to 12 mm. There was a significant difference between male and female cadavers regarding shallow PVH. Only the PVH as an independent variable had a significant correlation with the GPA location. The present study is the first to identify the different PVHs with customized stents and to correlate them with the distance of the GPA to the CEJ of maxillary teeth.

To evaluate the in vitro marginal integrity of CAD-CAM composite inlays with the proximal box margin relocated with different direct restorative materials before and after thermomechanical aging.Standardized 4 mm-wide Class II cavities were prepared in 40 sound human upper molars. The mesial cervical margin was located in enamel (control) and 1 mm occlusal to the cemento-enamel junction (CEJ), while the distal cervical margin was located in dentin (experimental) and 2 mm apical to the CEJ. In the experimental groups (n=10), the distal margins were relocated up to the CEJ level by using a highly viscous conventional glass ionomer cement (Equia Forte), low-viscosity bulk-fill composite (SureFil SDR Flow), highly viscous nanofilled composite (Filtek Supreme XT), or a highly viscous bulk-fill composite (Filtek Bulk Fill). The inlays were milled from CAD-CAM nanohybrid composite blocks (Brava Block) and luted with dual-cure resin cement (Allcem). The specimens were submitted to thermocycling (5-55°C, 7,800 cycles) and fatigue loading (50 N, 1 Hz, 240,000 cycles). Epoxy resin replicas of the margins were obtained before and after aging and evaluated through scanning electron microscopy. The percentage of continuous margin in relation to individual assessable margin was calculated as the marginal integrity. The data were statistically analyzed using Wilcoxon and Kruskal-Wallis tests (α= .05).The marginal integrity before and after aging was not significantly different (P0.05). Similarly, no significant differences were observed between margins relocated with different restorative materials in comparison to enamel margins (P0.05).Cervical margin relocation is a valid protocol to simplify intra-oral scanning and luting of CAD-CAM composite inlays with deep proximal margins. The marginal integrity at deep margins with relocation material was comparable to that of enamel margins.

OBJECTIVE: To examine effects of Radiation therapy (RT) for Head and Neck Cancer (HNC) on periodontal disease and relationships to caries. METHODS: Multicenter prospective observational cohort study conducted in patients undergoing RT for HNC. Assessments conducted by calibrated examiners at the pre-RT (baseline) visit (n=533), the 12-month visit (n=414), and the 24-month visit (n=365). RESULTS: Average whole mouth mean(SE) distance from the cemento-enamel junction to the gingival margin (CEJ-GM) decreased significantly from 0.43(0.04) mm at baseline to 0.24(0.04) mm at 12 months, and 0.11(0.04) mm at 24 months (p-values ≤0.001). Whole mouth mean(SE) percentage of sites with CEJ-GM distance of less than 0 mm increased significantly from 23.3%(1.0%) at baseline, to 28.5%(1.0%) at 12 months, and 30.5%(1.1%) at 24 months (p-values ≤0.02). Higher mean radiation dose to the mandible was associated with greater increase in percentage of mandibular sites with CEJ-GM distance of less than 0 mm (p=0.003). Both mean CEJ-GM distance and percentage of sites with CEJ-GM distance less than 0 mm were strongly associated with whole mouth mean proportion of decayed, missing, and filled surfaces, as well as proportion of decayed or filled facial/buccal surfaces specifically, (p-values

To evaluate the influence of the sonic device on the clinical performance of one-step self-etch adhesive systems in non-carious cervical lesions (NCCLs) after 18 months.Forty patients participated in this study. Eighty restorations were assigned to two groups (n = 40): Sonic application and Manual application. After the adhesive application (iBond Self-Etch, Kulzer, Hanau, Germany), NCCLs were restored using composite resin (Charisma, Kulzer, Hanau, Germany). The restorations were evaluated at baseline and after 18 months both according to the Word Dental Federation (FDI) and the United States Public Health Service (USPHS) criteria. Friedman repeated measures analysis of variance by rank and Wilcoxon test for significance in each pair were applied (α = 0.05).After 18 months, 38 patients were evaluated. Twenty-three restorations were lost (19 for manual vs. 4 for sonic application). The retention rates (95% confidence interval) were 50% (CI 34.8%-65.1%) for manual application and 84.2% (CI 69.6%-92.6%) for sonic application (p 0.05). Twelve restorations showed marginal staining (nine for manual vs. three for sonic application; FDI, p 0.05) and nine some marginal discrepancy (seven for manual vs. two for sonic application; FDI, p 0.05). No restorations showed postoperative sensitivity and caries recurrence at the time.The sonic application increases the retention rate of iBond Self-Etch after 18 months of clinical evaluation in NCCLs.The application of a simplified self-etch adhesive (iBond Self-Etch) associated to a sonic device seems to be an alternative to improve the clinical behavior in NCCLs.

In this clinical study, the 8-year clinical performances of a flowable resin composite was compared with that of a conventional resin composite.Ninety non-carious cervical lesions (NCCLs) in 19 participants were involved in this trial. NCCLs were restored with a flowable composite (Clearfil Flow FX: FX, Kuraray Noritake, Japan) or a conventional resin composite (Clearfil AP-X: AP) in conjunction with a one-step self-etch adhesive (Clearfil S3 Bond). Each participant had both types of resin composite restorations that were randomly allocated. The restorations were evaluated at baseline and annually up to 8 years using modified USPHS criteria. The data were statistically analyzed using the Fisher's exact test, Kaplan-Meier method, and a multivariate Cox-regression with frailty models (p 0.05).The 8-year participant recall rate was 95%. One hundred percent retention was recorded for AP, whereas four out of 46 restorations were lost for FX during the 8 years. The incidence of marginal staining increased over time regardless of the type of resin composite, showing 48% for AP and 57% for FX after 8 years. Wear of the resin composite occurred only for the flowable material and there was a significant difference between the types of resin composite (p = 0.024). Overall survival rates at 8 years for AP and FX were 98% and 82% respectively (p = 0.110).The flowable resin composite presented lower wear resistance and showed a lower survival rate compared with the conventional composite after eight years of clinical service.Flowable resin composites may show greater wear after long-term clinical service.UMIN000028745, Date of registration: August 19, 2017.

The present study aimed to compare the conventional clinical and a digital method for evaluating differences in gingival recession (ΔREC) in patients with advanced periodontitis treated with the non-surgical treatment protocol.Agreement between the methods was evaluated on a sample of ten patients with periodontitis (stage III/IV, grade B/C) with acquired clinical measurements and digital models from baseline (T0) and 12-months after non-surgical treatment of periodontitis (T1). The evaluation was performed on maxillary teeth from right to left second premolar resulting in overall 99 teeth. Clinical evaluation was performed by subtracting the distance measurements between gingival margin and cemento-enamel junction, obtained at T0 and T1 by a calibrated examiner (intra-examiner agreement90%). The digital evaluation was performed directly by measuring the distance between the gingival margins on superimposed T0 and T1 digital models. Using Bland-Altman and statistical analysis, all six measurements sites around each included tooth (n=594) acquired with both methods were compared.Median ΔREC (5th and 95th percentile) acquired with a conventional clinical and digital method was 0.0mm (-2.0 - 1.0) and -0.4mm (-1.6 - 0.8), respectively (p0.0001). The complete agreement between rounded digital and clinical ΔREC values was only 38%, revealing high disagreement also confirmed by Bland-Altman analysis with 95% limits of agreement ranging from -2.6 to 1.8mm. Absolute differences between the methods higher than 0.5 and 1 mm, was found in 61% and 38% of measurement sites, respectively.The conventional clinical method for ΔREC evaluation exhibits lower sensitivity and accuracy than the digital method.The quality of both clinical and research data in periodontology and implantology can be considerably improved by the digital method while still preserving the compatibility with the conventional clinical method.

The purpose of this clinical trial was to evaluate and compare the performances of three different universal adhesives used with a highly filled flowable universal resin composite in the restoration of non-carious cervical lesions (NCCLs) over a 60-month period.Ninety-nine NCCLs were restored at 18 participants. NCCLs were divided into three different universal adhesive groups: Clearfil Universal Bond (CU) (n = 31), iBOND Universal (IU) (n = 33), and G-Premio Bond (GP) (n = 35). Prior to the adhesive procedures, selective enamel etching was performed with 37% phosphoric acid in all experimental groups. Adhesive systems were applied following the manufacturers' instructions, and the lesions were restored with a highly filled flowable resin composite (G-ænial Universal Flo). Restorations were finished and polished immediately after placement. All restorations were scored with regard to retention, marginal discoloration, marginal adaptation, sensitivity, surface texture, and color match using modified United States Public Health Service (USPHS) criteria after 1 week (baseline) and 6, 12, 18, 24, 36, and 60 months. Statistical analyses were performed using chi-square and McNemar's and Kaplan Meier tests. The level of significance was set at p 0.05.After 60 months, the recall rate was 72.2%. Survival rates of CU, IU, and GP restorations were 87%, 85.2%, and 96.5%, respectively. Five CU (25%), 8 IU (34.8%), and 12 GP (42.9%) restorations exhibit bravo scores for marginal adaptation. However, no differences were seen among them. CU showed lower bravo score than IU and GP for marginal discoloration (CU, 0%; IU, 26.1%; GP, 32.1%). Two CU, 7 IU, and 6 GP restorations showed bravo scores for surface texture, and 2 (9.1%) CU and 1 (3.3%) GP restorations were scored as bravo score for color match (p 0.05).The tested universal adhesives showed similar success rates during the 60-month follow-up. However, CU showed better clinical performance than IU and GP in terms of marginal adaptation and discoloration.ClinicalTrials.gov Identifier: NCT03415412 CLINICAL RELEVANCE: The long-term clinical performances of the three universal adhesives in the restoration of NCCLs using selective enamel etching mode were successful after 60 months.

To determine the prevalence of non-carious cervical lesions (NCCLs) in maxillary premolars of different torques and simulated cervical stress profiles of the premolars under coincident loadings using finite element analysis (FEA).The CBCT scans of 616 maxillary premolars from 154 subjects were retrospectively evaluated. The premolars were ascribed into low torque group (LTG)-10.9°, medium torque group (MTG) -10.9° to -3.9°, and high torque group (HTG)-3.9°, when the torque was referring to the occlusion plane. The prevalence of NCCLs in each group was evaluated. Then finite element models of a maxillary first premolar, its adjacent teeth and alveolar bone were established. The models were prepared with ANSYS software generating the premolars presenting different torques. The mastication scenario for the premolars in maximum intercuspation position was simulated.The prevalence of NCCLs was 15.7% in LTG, 7.9% in MTG and 5.5% in HTG. The prevalence of LTG was significantly higher than that of MTG (P0.05) and HTG (P0.01). As for FEA, the stresses at the buccal necks of the premolars basically increased with decrease of the torque. The tensile stress peaks were in the cemento-enamel junction in most premolars of the LTG, while in the middle of the crowns in premolars of MTG and HTG.Low torque with excessive lingual inclination is a risk factor for NCCLs of maxillary premolars, and excessive tensile stress concentration in buccal necks during mastication may be responsible for that.

OBJECTIVE: To measure the three-dimensional morphology of the labial supraosseous gingiva (SOG) and the thickness of related labial bone in maxillary anterior teeth of periodontally healthy Han nationality youth using soft tissue indirect imaging cone-beam computed tomography (CBCT). METHODS: Twenty-five periodontally healthy subjects (11 males and 14 females) with 150 maxillary anterior teeth were involved in this study. A special impression with radiopaque material including the maxillary teeth was made, then a CBCT scan with the elastomeric matrix in position was taken for each subject. The imaging data were generated and transferred to a volumetric imaging software in which three-dimensional reconstruction was conducted and the image analyses were carried out. Measurements were made at the site of labial center of the maxillary anterior teeth. The height of the SOG, the distance between cemento-enamel junction (CEJ) and bone crest, the gingival thickness at the CEJ, and the thickness of bone 2 mm below the labial bone crest were measured and the correlation analysis between the parameters was made. All the data analyses were performed using SPSS 22.0. The data were analyzed with ANVOA and Pearson correlation tests with the significance level at α=0.05. RESULTS: The mean SOG values were (3.49±0.70) mm, (3.48±0.81) mm, and (3.54±0.67) mm for central incisors, lateral incisors and canines, respectively. There were no statistically significant differences among the different sites (P > 0.05). The mean gingival thickness values were (1.45±0.23) mm, (1.13±0.24) mm, (1.14±0.22) mm for central incisors, lateral incisors and canines, respectively. The gingival thickness of the central incisors was the largest among the maxillary anterior teeth with statistically significant difference (P < 0.05). No correlation was found between the SOG and gingival thickness among the maxillary anterior teeth (P > 0.05). CONCLUSION: The gingival thickness of central incisors was the largest and the supraosseous gingival height had no correlation with gingival thickness among the periodontally healthy maxillary anterior teeth.

Background The extent of gingival recession represents one of the most important measures determining outcome of periodontal plastic surgery. The accurate measurements are, thus, critical for optimal treatment planning and outcome evaluation. Present study aimed to introduce automated curvature-based digital gingival recession measurements, evaluate the agreement and reliability of manual measurements, and identify sources of manual variability. Methods Measurement of gingival recessions was performed manually by three examiners and automatically using curvature analysis on representative cross-sections (n = 60). Cemento-enamel junction (CEJ) and gingival margin (GM) measurement points selection was the only variable. Agreement and reliability of measurements were analysed using intra- and inter-examiner correlations and Bland–Altman plots. Measurement point selection variability was evaluated with manual point distance deviation from an automatic point. The effect of curvature on manual point selection was evaluated with scatter plots. Results Bland–Altman plots revealed a high variability of examiner’s recession measurements indicated by high 95% limits of agreement range of approximately 1 mm and several outliers beyond the limits of agreement. CEJ point selection was the main source of examiner’s variability due to smaller curvature values than GM, i.e., median values of − 0.98 mm− 1 and − 4.39 mm− 1, respectively, indicating straighter profile for CEJ point. Scatter plots revealed inverse relationship between curvature and examiner deviation for CEJ point, indicating a threshold curvature value around 1 mm− 1. Conclusions Automated curvature-based approach increases the precision of recession measurements by reproducible measurement point selection. Proposed approach allows evaluation of teeth with indistinguishable CEJ that could be not be included in the previous studies.

Made available in DSpace on 2022-05-01T08:44:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 The presence of a tooth-surface defect, such as a non-carious cervical lesion (NCCL), associated with sites of gingival recession (GR) defects creates a combined soft tissue/tooth defect (CD) that requires a different treatment plan. This study aimed to critically review the literature regarding the available treatment protocols for CDs and suggest a new decision-making process. NCCLs were classified as Class A-: the cementoenamel junction (CEJ) was visible and the root surface discrepancy was < 0.5 mm (no step); Class A+: CEJ was visible and the root surface discrepancy was > 0.5 mm (with a step); Class B-: unidentifiable CEJ without a step; Class B+: unidentifiable CEJ with a step. NCCLs affecting both root and crown surfaces (Class B) lead to CEJ destruction and consequently eliminate an important landmark used before and after root coverage procedures. The depth of the root surface discrepancy is vital owing to its possible impact on soft tissue adaptation after healing, which, in turn, may influence the treatment options, namely the use of graft and/or composites to compensate for the discrepancy. Clinically, a step with horizontal depth greater than 0.5 mm should be recognized as the minimum threshold value to define this condition. Extremely deep defects tend to assume a V-shaped topography. Therefore, extremely deep V-shaped defects were classified into subclasses A+V, a V-shaped defect, and B+V, a V-shaped defect with loss of CEJ, for management considerations. The treatment options, supported by the literature, and a decision-making process to deal with each condition are presented. Universidade Estadual Paulista — Unesp Institute of Science and Technology Department of Diagnosis and Surgery Universidade Estadual de Campinas — Unicamp Piracicaba Dental School Department of Prosthodontics and Periodontics Universidade de São Paulo — USP School of Dentistry Department of Stomatology Tuscany Academy of Dental Research — ATRO Universidade Estadual Paulista — Unesp Institute of Science and Technology Department of Diagnosis and Surgery

Human dentin consists of a primary layer produced during tooth formation in early childhood and a second layer which first forms upon tooth eruption and continues throughout life, termed secondary dentin (SD). The effect of attrition on SD formation was considered to be confined to the area subjacent to attrition facets. However, due to a lack of three-dimensional methodologies to demonstrate the structure of the SD, this association could not be determined. Therefore, in the current study, we aimed to explore the thickening pattern of the SD in relation to the amount of occlusal and interproximal attrition. A total of 30 premolars (50–60 years of age) with varying attrition rates were evaluated using micro-computerized tomography. The results revealed thickening of the SD below the cementoenamel junction (CEJ), mostly in the mesial and distal aspects of the root (p &lt, 0.05). The pattern of thickening under the tooth cervix, rather than in proximity to attrition facets, was consistent regardless of the attrition level. The amount of SD thickening mildly correlated with occlusal attrition (r = 0.577, p &lt, 0.05) and not with interproximal attrition. The thickening of the SD below the CEJ coincided with previous finite element models, suggesting that this area is mostly subjected to stress due to occlusal loadings. Therefore, we suggest that the SD formation might serve as a compensatory mechanism aimed to strengthen tooth structure against deflection caused by mechanical loading. Our study suggests that occlusal forces may play a significant role in SD formation.

The objective of this study was to determine the age-related anatomical changes that take place at the cementodentinal junction (CDJ).Eighty-four teeth were extracted; 42 samples came from patients ranging in age from 18 to 30 years, and 42 came from patients aged from 40 to 60 years. Upper and lower and anterior and posterior teeth were included. Longitudinal slices were made, and 1% toluidine blue was used to stain all the samples prior to microscopic examination. Anatomical landmarks (apical foramen [AF], apical vertex, and cementoenamel junction) in the apical third were identified, and a pre-calibrated software package was employed to take digital measurements. Statistical analysis was performed by means of the Wilcoxon rank-sum test.The data obtained showed that there were anatomical variations in the apical third in the older patients and that these changes were related to the age of the patient. Narrower root canals and smaller CDJ diameters were found in older patients' samples.The results of this study suggest that instrumentation and obturation should take place 1 mm from the AF in older patients, and not 0.5 mm, as is usually recommended.

OBJECTIVE: To evaluate the influence of base materials on stress distribution in endodontically treated maxillary premolars restored with endocrowns using three-dimensional finite element analysis. METHODS: A maxillary second premolar was scanned by Micro-CT and a three-dimensional finite element model of ceramic endocrown with 1 mm thickness of base was established. A model without base was also established as a negative control. Four kinds of conventional base materials with different elastic modulus were adopted: light cure glass ionomer(3M Vitrebond, 3 657 MPa), flowable composite resin(3M Filtek Z350XT Flowable Restorative, 7 300 MPa), high strength glass ionomer(GC Fuji Ⅸ, 13 130 MPa), and posterior composite resin(3M Filtek P60, 19 700 MPa). With a 200 N force loaded vertically and obliquely, the distribution and magnitude of stress in the tooth tissue and adhesive layer were investigated by three-dimensional finite element analysis. RESULTS: The maximum von Mises stress values(vertical/oblique) in dentin and adhesive layer were measured as follows: (1) no base material: 19.39/70.49 MPa in dentin and 6.97/17.97 MPa in adhesive layer; (2) light cure glass ionomer: 19.00/69.75 MPa in dentin and 6.87/16.30 MPa in adhesive layer; (3) flowable composite resin: 18.78/69.33 MPa in dentin and 6.79/16.17 MPa in adhesive layer; (4) high strength glass ionomer: 18.71/69.20 MPa in dentin and 6.74/16.07 MPa in adhesive layer; (5) posterior composite resin: 18.61/69.03 MPa in dentin and 6.70/16.01 MPa in adhesive layer. Under the same loading condition, models with different elastic moduli of base materials had similar stress distribution patterns. The von Mises stress of tooth tissue was mainly concentrated in the tooth cervix. Under oblique load, the regions where von Mises stress concentrated in were similar to those under a vertical load, but the values increased. The stress concentration in the tooth cervix was alleviated in models with base materials compared with the model without base material. The maximum von Mises stress in the tooth tissue and adhesive layer decreased when the elastic modulus of base materials increased and got close to that of dentin. CONCLUSION: The posterior composite resin of which the elastic moduli is high and close to that of dentin is recommended as base material for premolar endocrowns to alleviate the concentration of stress in tooth cervix and adhesive layer.

Objective To analyze the prevalence of distal caries in mandibular second molars (M2Ms) and its correlation with the three-dimensional position of mandibular third molars (M3Ms) by cone beam computed tomography (CBCT) images. Materials and methods CBCT scans involving 421 M3Ms were assessed. The presence of distal caries of M2Ms, patient age and gender, impaction depths and mesial angulation of M3Ms, the cementoenamel junction (CEJ) distances and contact point localization, and the horizontal positions of M3Ms were assessed. Risk factors were identified by multivariate logistic regression analysis. Results The overall prevalence of distal caries in M2Ms was 31.6%. Mesial angulation (16°–75°) of M3Ms, contact point localization at or below the CEJ of M2Ms, and a buccal or lingual position of M3Ms relative to the molar line were identified as risk factors for the prevalence of distal caries in M2Ms (p p Conclusions Buccal or lingual position of M3Ms may represent a new risk factor for the distal caries in M2Ms. Mesial angulation (16°–75°) of M3Ms is a predictive parameter for both the presence and severity of distal caries in M2Ms. Clinical relevance As the presence of distal caries in M2Ms is significantly associated with the three-dimensional position of M3Ms, watchful monitoring or prophylactic removal of M3Ms should be deliberated when M3Ms are mesially angulated (16°–75°), buccally or lingually positioned, and with the contact point localization at or below the CEJ of M2Ms.

Background: Abfraction is a loss of tooth structure along the gingival margin and manifests with different clinical appearances. It has multifactorial etiology and may occur due to normal and abnormal tooth function and may also be accompanied by pathological wear, such as abrasion and erosion. The theory behind the abfraction is that the tooth flexure in the cervical area is caused due to occlusal compressive forces and tensile stresses. This results in the fractures in the hydroxyapatite (HA) crystals. It is also caused by the low packing density of the Hunter–Schreger band (HSB) at the cervical area. Unfortunately, there is a lack of evidence regarding the outcome of abfraction with or without intervention. The aim of this review is to collect clinical information from the literature and discuss the etiology, pathogenesis, clinical representation, and management. Also, search databases for clinical studies that describe the role of sclerotic dentine in non-carious cervical lesions (NCCLs) are becoming a clinical challenge. Methods: The literature was searched that described the etiology, pathogenesis, clinical representation, and management of the abfraction lesions. Also, a specific question regarding the formation of sclerotic dentin in the NCCL lesion was described and searched for evidence that challenges etching, bonding, and successfully restoring NCCLs. The databases PUBMED, SCOPUS, MEDLINE, WEB of SCIENCE, and EMBASE were searched using the key terms. The inclusion criteria were the randomized controlled clinical trial, cohort studies, and cross-sectional studies that aimed at determining the role of sclerotic dentine in NCCLs and its effect on etching, bonding. Results: One clinical study was retrieved according to the PRISMA flowchart and PICO format. The longer etching time, total-etch adhesive system, and EDTA pre-treatment of the sclerotic dentin of cervical wedge-shaped defects could improve the bonding strength in lesions like NCCL's. Conclusion: In conclusion, clinical challenges that occur due to NCCLs are better managed by a proper understanding of factors like etiopathogenesis, ultra-structure of enamel, and dentine and their effect on the bonding of restorations of the tooth.

Objective. The aim of this paper was to analyze the distribution of stress and deformation on the man­dibular first premolar under two types of loading (axial and para-axial load of 200 N) using the FEM computer method. Materials and Method. For this research a μCT scan of the first mandibular premolar was used, and the method used in this research was FEM analysis under two types of loading. Results. The values of the von Mises stress measured in the cervical part of an intact tooth under axial load were up to 12 MPa, and under paraaxial load over 50 MPa. The val­ues of the stress measured on the bottom of the non-carious lesion are very high ≈ 240 Mpa. Stress values in the cervical part of the intact tooth are higher in the zone of the sub-surface enamel. The deformation values of the tooth under para-axial loading were ≈ 10 times higher than the value of the deformation under axial load. The greatest deformations were seen in the area of the tooth crown. Conclusions. Occlusal load­ing leads to significant stress in the cervical part of teeth. The values of the measured stress are greater un­der the action of paraxial load. The values of stress in abfraction lesions measured under a paraxial load are extremely high. Exposing the lesion to further stress will lead to its deepening. The total deformation of the entire tooth under paraxial load was ≈ 10 times higher compared to the deformation value of the tooth under axial load.

The aim of this clinical trial was to evaluate and compare the performance of a universal adhesive with different adhesive strategies in the restoration of non-carious cervical lesions (NCCLs) over a 36-month period. One hundred sixty-five NCCLs in 35 patients (13 female, 22 male) with at least 3 lesions each were included in this study. Three groups were formed according to the adhesive strategy used (n = 55): selective-etch mode, etch-and-rinse mode, or self-etch mode of a universal adhesive, Single Bond Universal. The same nanofilled resin composite, Filtek Ultimate, was used for all restorations by a single operator. The restorations were evaluated by two calibrated examiners at baseline and at 6, 12, 18, 24, and 36 months in accordance with the modified USPHS criteria. The chi-square test was used for intergroup comparison and Cochran’s Q test for intragroup comparison (∝ = 5%). At 36 months, the recall rate was 98.1% and three restorations, one from each group, had failed because of retention loss (P > 0.05). The self-etch mode group showed 17 bravo scores for both marginal staining and marginal adaptation after 3 years, which was significantly different from the selective-etch and etch-and-rinse groups (P

To investigate the prevalence of different patterns of cemento-enamel junction (CEJ) morphology under swept-source optical coherence tomography (SS-OCT). One hundred extracted human teeth were used consisting of incisors, premolars, and molars. Each sample was observed for every 500 μm circumferentially along CEJ and OCT images of the pattern were noted. Microscopic observations were done for the representative sample using confocal laser scanning microscope (CLSM) and transmission electron microscope (TEM). The OCT images exhibited four CEJ patterns: edge-to-edge (type I), exposed dentin (type II), cementum overlapping enamel (type III), and enamel overlapping cementum (type IV). The prevalence of CEJ patterns was further statistically considered for mesial, distal, buccal, and lingual surfaces. The real-time imaging by SS-OCT instantly determined CEJ morphology. CLSM and TEM observation revealed morphological features along CEJ, which corresponded to OCT images of CEJ anatomy. OCT results showed 56.8% of type I pattern predominantly found on proximal surfaces, followed by 36.5% of type II pattern on buccal and lingual surface, 6.4% of type III pattern, and 0.3% of type IV pattern. There was a significant difference in prevalence of CEJ patterns among different types of teeth, but there was no statistically significant difference among the four surfaces in each type of teeth. OCT is a non-invasive diagnostic tool to examine the CEJ patterns along the entire circumference. OCT observation revealed even minor dentin exposure that would need clinical and home procedures to prevent any symptoms.

Objectives This study investigated the effect of toothbrush bristle configuration and brushing load on the development of non-carious cervical lesions (NCCLs). Methods Human premolars were mounted on acrylic blocks and had their root surfaces partially covered with acrylic resin to simulate gingiva, leaving a 2-mm length area apical to the cemento-enamel junction exposed for brushing. The teeth were brushed under 1- or 3 N load with one of the following toothbrushes (n = 16): a) ordinary/flat-trimmed (Oral-B Indicator); b) rippled (Oral-B Contour); c) cross-angled/multileveled/rubber bristles (Oral-B Pro-Health All-in-One); d) cross-angled/multileveled/flex head (Oral-B Pro-Flex); e) feathered (Oral-B Compact Clean). Brushing was performed using toothpaste slurry (Crest Cavity Protection) for 55,000 double-strokes in back-and-forth motion, to simulate 10 years of brushing. Impressions were taken at baseline and after brushing and scanned by a 3D optical profilometer. The lesions formed were evaluated for volume loss, angle, and shape. Results The ordinary/flat-trimmed toothbrush caused significantly higher volume loss (3.81 mm3) in comparison to the other toothbrushes (2.56-2.92 mm3). The toothbrush having rubber bristles was associated with NCCLs showing the smallest angle and, along with the rippled toothbrush (53.1%), provoked higher proportion of wedge-shaped lesions (43.8%), whereas teeth brushed with the feathered toothbrush exhibited the lowest prevalence of wedge-shaped lesions (3.1%). The 1- and 3 N load applied during brushing affected neither volume loss nor lesion angle. Conclusions At the brushing loads tested, the development of NCCLs was dependent on toothbrush bristle configuration, with the ordinary/flat-trimmed version causing the highest abrasion and the feathered toothbrush the least proportion of wedge-shaped lesions. Clinical significance Toothbrush bristle arrangement plays a role in NCCL development, with the ordinary/flat-trimmed version being more abrasive and the feathered toothbrush causing less wedge-shaped lesions.

The aim of this work was to compare the duration of treatment between orthodontic treatment combined with piezocorticision (OT-PC) and conventional orthodontic treatment (COT), as well as to evaluate the safety, inflammatory process, periodontal health, and soft tissue healing in the OT-PC group.Twelve patients were included in each group, and their treatment times were compared for preliminary bracket alignment (PBA) and for overall treatment. In the OT-PC group, the inflammatory process was evaluated by quantifying cytokines in the gingival crevicular fluid. A calibrated examiner measured the probing depth (PD), the distance between the gingival margin and the cementoenamel junction (GM-CEJ), and the clinical attachment level (CAL), before and after OT-PC. The presence of gingival scars was evaluated. Bone and root injuries were assessed with the use of cone-beam computed tomography.The treatment time was significantly reduced in the OT-PC group for PBA in both maxilla (45%; P = 0.001) and mandible (31%; P = 0.023), as well as for overall treatment (52%; P 0.0001). Although not statistically significant, several inflammatory mediators demonstrated peaks at 3-5 and 16 weeks. There were not significant changes in PD and GM-CEJ after OT-PC treatment, unlike CAL (0.09 ± 0.12 mm; P = 0.024); 47.5% of piezocorticisions caused gingival scars. Only one patient showed no scars. Four cortical bones did not heal completely, and 2 roots had piezoelectric injuries.OT-PC was effective at reducing the orthodontic treatment time.

Despite the fact that external cervical resorption (ECR) is a well-known and rather frequently met condition, the driving force of this phenomenon still remains unclear. Recently, hypoxia has been linked to ECR. Thus, the aim of this work was to investigate the existence of hypoxia in ECR and hypothesize on its role at the time of extraction. This work is a case study of a tooth with ECR. ECR diagnosis was based on clinical and radiographic examination with cone-beam computed tomographic imaging. The extracted tooth was further analyzed by using nanofocus computed tomographic imaging and immunohistology. To investigate the 3-dimensional extent and pattern of ECR, in vivo cone-beam computed tomographic imaging and ex vivo nanofocus computed tomographic imaging were used. Different histologic stains were used to investigate the presence of a hypoxic environment and to gain a better insight into the involved cells, neuronal structures, and remodeling process during ECR. A higher distribution of hypoxia-inducible factor 1a–positive cells was found in the apical part of the resorption area when compared with the coronal area of the resorption. In addition, a similar distribution of hypoxia-inducible factor 1a–positive odontoblasts was observed in the pulp. Three-dimensional analysis of the calcification of the pulp revealed the formation of pulp stones in areas with higher hypoxia. Histology showed that remodeling during ECR can occur according to a layered pattern. This investigation confirms the presence of hypoxia in ECR and shows that there is a gradient of hypoxia within the ECR lesion and surrounding tooth structure. The hypoxic environment within the pulp is also indicated by the formation of pulp stones.

Objective This study aimed to evaluate the effect of prolonging polymerization time on the 18 months clinical performance of a universal adhesive system used as etch-and-rinse (ER) and self-etch (SE). Methods 140 restorations were randomly placed in 35 subjects according to the following groups: ER10 (light-curing for 10 s); ER40 (light-curing for 40 s); SE10 (light-curing for 10 s) and; SE40 (light-curing for 40 s/1200 mW/cm2). A resin composite was placed incrementally. The restorations were evaluated at baseline and after 18 months by using the FDI criteria. The following outcomes were evaluated: marginal staining, marginal adaptation, spontaneous post-operative sensitivity and recurrence of caries. The differences among the groups were calculated using Friedman repeated measures analysis of variance rank (α = 0.05). Results After 18 months the retention/fracture rates were 88.9% (95%CI 74.1–95.6%) for ER10, 94.3% (95%CI 91.4–98.5%) for ER40, 77.2% (95%CI 60.1–87.9) for SE10 and 97.2% (95%CI 85.5–99.9%) for SE40. A significant difference was detected in the retention rate when SE10 was compared to the SE40 (p = 0.01). Also, ER40 showed a significant improvement of the marginal adaptation when compared to ER10 (p = 0.01). Significance This is the first study that demonstrates an improvement in the clinical performance of universal adhesive systems in non-carious cervical lesions when prolonged light-cured was applied.

Mild and intermediately strong 2-step self-etch adhesives (2SEa) have been shown to bond efficiently to dentin. In general, their bonding efficiency to enamel is inferior to that of etchrinse adhesives (ERa). On the other hand, their application procedure is less elaborate, and consequently leaves less room for application mistakes. The aim of this randomized controlled trial was to evaluate the clinical performance of an intermediately strong 2SEa, as compared with that of a 3-step ERa after 6 years of clinical functioning.239 non-carious cervical lesions in 50 patients were restored with the nanohybrid composite Herculite XRV (Kerr), bonded in random order either with the 2SEa Optibond XTR ('O-XTR', Kerr) or the gold-standard control 3ERa Optibond FL ('O-FL', Kerr). The restorations were recalled after 1, 2 and 6 years of clinical service and examined for retention, marginal adaptation, marginal discoloration, caries occurrence, and postoperative sensitivity. Statistical analysis was performed using a logistic regression model with generalized estimating equations (2-way GEE model).The patient recall rate at 6 years was 94%. The overall clinical success rate was 81.9% and 80.9% for O-XTR and O-FL, respectively. In total, 42 restorations (21 O-XTR, 21 O-FL) failed because of retention loss, severe abfraction/abrasion/erosion, severe marginal defects and/or discoloration, and/or caries. A retention rate of 92.9% and 88.9% was recorded for O-XTR and O-FL, respectively. Progressive marginal deterioration was observed over the 6-year period. Small clinically acceptable marginal defects were recorded in about 70% of the restorations (O-XTR: 69.9%; O-FL: 74.1%). Regarding marginal discoloration, 37% of the O-XTR and 30.2% of the O-FL restorations showed superficial clinically acceptable marginal discoloration. Six O-XTR and 4 O-FL restorations exhibited caries at the restoration margin. No significant difference was observed between the two groups for any of the evaluated parameters (p0.05).After 6 years of clinical service, Class-V restorations bonded with the 2SEa performed clinically equally well as those bonded with the 3ERa.

Non-carious cervical lesions (NCCLs) are characterized by a loss of hard dental tissue near the cement–enamel junction with multifactorial etiology. The aim of this study was to demonstrate that occlusal factors as attrition, malocclusion, and bruxism, and mental disorders as depression, stress, and anxiety are involved in the etiology of NCCLs. Salivary samples and clinical data of 340 individuals selected from 6,112 participants were obtained from the University of Pittsburgh School of Dental Medicine Dental Registry and DNA Repository project. The affected group was formed by individuals with NCCL (34 females, 34 males, mean age 55.34 years). In addition, the comparison group was formed by individuals without NCCL (136 females, 136 males, mean age 55.14 years). Eleven single-nucleotide polymorphisms (SNPs) previously associated with mental disorders were genotyped and tested for association with NCCLs. When all occlusal factors were combined there was found a significant association with NCCL (p = 0.000001/adjusted OR 4.38, 95% CI 2.50–7.69). Attrition (OR 3.56, 95% CI 2.00–6.32) and malocclusion (OR 5.09, 95% CI 1.65–15.68) as separate variables showed statistically significant associations with NCCL. There was a significant difference in stress history between the two groups (OR 2.17, 95% CI 1.08–4.39). No associations between NCCLs and the SNPs selected were found. However, when the occlusal factors were analyzed as covariates, associations were found between bruxism and seven of the selected SNPs. Our results suggest that occlusal factors might be associated with NCCLs.

The purpose of this multicenter clinical study was to compare the mid-term clinical effectiveness of direct resin composite restorations using one-step or two-step self-etch adhesives (1-SEAs or 2-SEAs). In total, 352 restorations of class I–V cavities and non-carious cervical lesions in vital teeth (1-SEAs; 52 cases, 2-SEAs; 300 cases) were placed at nine university hospitals and evaluated according to the modified USPHS criteria at baseline, and after 1, 2, and 3 years. The recall rates were 86.6% (1 year), 80.1% (2 years), and 62.2% (3 years). Two restorations failed due to fracture during the follow-up, and there was no significant difference in survival rates between 1-SEAs (97.6%) and 2-SEAs (99.4%). However, 2-SEAs exhibited significantly lower occurrences of discoloration, marginal discoloration, fracture, and plaque retention. Moreover, the subjects reported a significantly lower postoperative hypersensitivity and higher overall satisfaction at all evaluation periods if 2-SEAs were used.