Cervical wear pathobiology by robot-simulated 3-year toothbrushing - New methodological approach

OBJECTIVES

An ex-vivo study was aimed at (i) programming clinically validated robot three-year random toothbrushing, (ii) evaluating cervical macro- and microwear patterns on all tooth groups of different functional age, (iii) documenting and codificating wear related morphological features at the cemento-enamel junction in young teeth and on roots in older teeth.

DESIGN

Following ethical approval random toothbrushing (44 strokes per tooth horizontally, rotating, vertically; 2x/d) with manual toothbrushes and low-abrasive dentifrice was performed in an artificial oral cavity with brushing-force 3.5 N on 14 extracted human teeth. Morphological features were examined by SEM at baseline and after simulated 3 years using the replication technique. 3D-SEM analyses were carried out with a four-quadrant back scattered electron detector. Wilcoxon-Mann-Whitney-test was used for statistical analyses.

RESULTS

3-year random toothbrushing with horizontal, rotating and vertical brushing movements revealed morphological features classified as four enamel patterns, one dentin pattern and three cervical patterns. Negative impacts were enamel, cementum and dentin loss. Positive impact on oral health was removing dental calculus and straightening cervical traumatic and iatrogenic damages. The volume loss varied from x̅=34.25nl to x̅=87.75nl. Wear extended apically from 100 to 1500 micrometres.

CONCLUSION

Robot simulated toothbrushing in an artificial oral cavity, with subsequent SEM and 3D-SEM assessment, elucidated both negative and oral health-contributing micromorphology patterns of cervical wear after simulated 3-year random toothbrushing. Cervical macro- and microwear of cementum revealed, for the first time, what we describe as overhanging enamel peninsulas and enamel islands on roots in young teeth, but no enamel islands on roots from older teeth after root cementum loss. In contrast, many older teeth exhibited enamel peninsulas.

A depth-resolved quantitative evaluation method for non-carious cervical lesions treatment with optical coherence tomography

OBJECTIVES

The aim of this study is prognostic assessment of surface smoothness and the presence of internal bubbles after treatment of non-cancerous cervical lesions (NCCLs) using optical coherence tomography (OCT).

METHODS

After treatment with NCCLs, cross-sectional images of the lesion parts of the sample were non-invasively acquired and analyzed. The surface smoothness between tooth and resin, resin and cemento-enamel junction, and the presence bubble inside resin was confirmed. In addition, using an algorithm that distinguishes between resin and dental structure based on OCT cross-sectional images, we quantitatively analyzed the amount of resin used in treating NCCLs and acquired 3D images.

RESULTS

The inner structure of the resin in each sample was checked, and the presence of bubbles was confirmed. In addition, the resin sections were separated from the tomographic images acquired by OCT to visualize 3D images. The volume of resin used in the treatment part of each NCCLs samples was quantitatively analyzed as 3.7216 ∼ 14.889 mm3.

CONCLUSIONS

OCT is able to measure not only the surface abrasion provided by existing intraoral scanner, but also the size and depth location of interal bubbles, which is distinctive advantage of our method. Based on our results, OCT is a significant tool for qualitative and quantitative analysis of dental NCCLs treatment before and after treatment.

CLINICAL SIGNIFICANCE

The study used OCT, a non-destructive diagnostic, to reveal the structure of the resin and the location and size of bubbles after NCCLs treatment. These findings could be golden standard in determining the prognosis of NCCLs treatment.

Clinical performance of preheating thermoviscous composite resin for non-carious cervical lesions restoration: A 24-month randomized clinical trial

OBJECTIVES

This 24-month, double-blind, split-mouth randomized clinical trial aimed to compare the retention rates of a preheated thermoviscous composite resin (PHT) compared to a non-heated composite resin (NHT) in non-carious cervical lesions (NCCLs).

METHODS

A total of 120 restorations were restored on NCCLs using a preheated (VisCalor bulk, Voco GmbH) and a non-heated (Admira Fusion, Voco GmbH) composite resins with 60 restorations per group. A universal adhesive in the selective enamel conditioning was applied. In the PHT group, composite was heated at 68 °C for using a bench heater. In the NHT group, no heating was employed. Both restorative materials were dispensed into caps and inserted into the NCCLs. The restorations were evaluated at baseline, 6, 12, 18, and after 24 months of clinical service using the FDI criteria. Statistical analysis was performed with Kaplan-Meier estimation analysis for retention/fracture rate and Chi-square test for the other FDI parameters (α=0.05).

RESULTS

After 24 months 108 restorations were assessed. Seven restorations were lost (two for PHT group and five for NHT group), and the retention rates (95 % confidence interval [CI]) were 96.7 % (81.5-99.9) for PHT group and 90.8 % (81.1-96.0) for NHT group, with no statistical differences between them (p > 0.05). The hazard ratio (95 % CI) was 0.52 (0.27 to 1.01), with no significant difference within groups. In terms of all other FDI parameters that were assessed, all restorations were deemed clinically acceptable.

CONCLUSIONS

Both composites showed high rates of retention rates after 24 months.

CLINICAL SIGNIFICANCE

The clinical performance of the new preheated thermoviscous was found to be as good as the non-heated composite after 24-month of clinical evaluation in non-carious cervical lesions.

REGISTRATION OF CLINICAL TRIALS

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Investigation of the presence of Non-carious cervical lesions (NCCLs) in ancient adult skulls: analyzing data from prehistoric and historical samples through a systematic review and meta-analysis

OBJECTIVES

Historically, the prevalence of caries has undergone significant changes, particularly increasing with the industrialization of sugar consumption. When examining ancient populations, lower caries rates are discovered, attributed in part to dietary factors. These populations consumed abrasive foods, leading to occlusal wear and reduced non-axial occlusal forces, potentially influencing Non-Carious Cervical Lesions (NCCLs). Although some attribute NCCLs to abfraction, the mechanism remains debated. This systematic review aims to evaluate the presence of NCCLs in ancient populations, shedding light on the factors contributing to their occurrence.

MATERIALS AND METHODS

The present systematic review was registered on PROSPERO, and the manuscript was prepared following PRISMA guidelines.

RESULTS

After the literature search and article screening, data from 6 studies were included in the meta-analysis, with only 2 reporting NCCLs in ancient skulls, encopassing 17 subjects in 805 examined skulls, suggesting their presence even before the widespread use of toothbrushes. This finding indicates a potential etiopathogenic mechanism linked to abfraction, but the cause is complex and involves abrasive and erosive factors closely tied to dietary habits.

CONCLUSIONS

In summary, NCCLs were present in ancient populations, albeit with a much lower prevalence. Their occurrence cannot be solely attributed to wear mechanisms but must be connected to abrasive factors related to diet or practices with religious and cultural significance, such as the use of labrets.

CLINICAL RELEVANCE

Th the knowledge of NCCLs presence in acient sculls is crucial today for better understand the associated risk factors. In this context, the analysis of ancient skulls allows us to discern the role that tooth brushing and diet played in the formation of NCCLs, over the past century.

Sixty-month comperative evaluation of a glass hybrid restorative and a composite resin in non-carious cervical lesions of bruxist individuals

OBJECTIVE

To compare the clinical performance of a glass hybrid (GH) restorative and a nano-ceramic composite resin (CR) in the restoration of non-carious cervical lesions (NCCLs) of bruxist individuals in a 60-month randomized clinical trial.

MATERIALS AND METHODS

Twenty-five bruxist candidates having NCCLs were recruited in this clinical study. The depth, height (cervico-incisal), width (mesio-distal), internal angles of the NCCLs, degree of tooth wear (TWI) and gingival index (GI) were measured. One hundred-and-forty-eight NCCLs were restored either with a GH restorative (Equia Forte Fil) or a CR (Ceram.X One Universal). Modified USPHS criteria was used to evaluate restorations after 1 week and 12, 24, 36 and 60 months. Pearson's Chi-Square, Fisher's Exact and Cochran Q tests were run for analysis. Survival rates of the restorations were compared with Kaplan-Meier analysis (p < 0.05).

RESULTS

After 60 months, 97 restorations in 15 patients were examined. The recall rate was 60.0%. Retention rates were 73.5% for CR and 66.7% for GH. A total of 29 restorations were lost (13CR (26.5%), 16GH (33.3%)). There was not a significant difference between tested restoratives in retention (p = 0.464), marginal adaptation (p = 0.856) and marginal discoloration (p = 0.273). There was no relationship between internal angle, depth, height or width and retention of the GH or CR restorations (p > 0.05). The increase in retention loss and marginal discoloration of both restorations over time were significant (p < 0.001). Sensitivity or secondary caries were not detected after 60 months.

CONCLUSION

GH and nano-ceramic CR showed similar clinical performances in NCCLs after 60 months in patients with bruxism.

CLINICAL SIGNIFICANCE

After 60 months, CR and GH materials showed clinically acceptable performances in restoration of NCCLs in patients with bruxism.

Prolonged polymerization of a universal adhesive in non-carious cervical lesions: 36-month double-blind randomized clinical trial

OBJECTIVE

To evaluate the effect of prolonged (P) polymerization time of a universal adhesive system applied in etch-and-rinse (ER) or self-etch (SE) strategies on the clinical performance of restorations in non-carious cervical lesions (NCCLs), after 36 months of clinical service.

METHODS

A total of 140 restorations were randomly placed in 35 subjects according to the polymerization time groups: ER (10 s); ER-P (40 s); SE (10 s); and SE-P (40 s) at 1,200 mW/cm2. Composite resin was placed incrementally. The restorations were evaluated immediately and after 6, 12, 18, and 36 months using the FDI criteria. Data were analyzed using the Kaplan-Meier survival test for retention loss, and the Kruskal-Wallis' test for secondary outcomes (α = 0.05).

RESULTS

After 36 months, 19 restorations were lost: ER 6, ER-P 2, SE 9, SE-P 2. The retention rates were 82.3% for ER; 94.1 % for ER-P; 73.5 % for SE; and 94.1 % for SE-P, with a significant difference between ER vs. ER-P and SE vs. SE-P, as well as ER vs. SE-P and ER-P vs. SE (p < 0.0001). Minor defects were observed in 18 restorations for the marginal staining criteria: ER 5, ER-P 2, SE 8, SE-P 3; and in 33 restorations for the marginal adaptation criteria: ER 11, ER-P 4, SE 12, and SE-P 6 (p > 0.05). No restorations showed recurrence of caries or postoperative sensitivity.

CONCLUSIONS

A prolonged polymerization time of 40 s improves the clinical performance of the universal adhesive for both adhesive strategies evaluated, even after 36 months.

CLINICAL SIGNIFICANCE

Prolonging the polymerization time of a universal adhesive from 10 to 40 s has been shown to improve its clinical performance when used in NCCLs.

Prevalence and Characterization of External Cervical Resorption Using Cone Beam Computed Tomography

INTRODUCTION

The aim of this study was to assess the prevalence of external cervical resorption (ECR) and characterize the cases of ECR using cone beam computed tomography (CBCT).

METHODS

High-resolution CBCT scans of 6216 patients (2280 males and 3936 females), consecutively acquired during the period July 2021 to March 2022, were analyzed. Identified cases of ECR were characterized by 3 evaluators regarding lesion height, circumferential spread, portal of entry proximity to root canal, stage, location, and width.

RESULTS

In a total of 38 patients and 40 teeth, ECR cases demonstrated an incidence of 0.61%. The median age of the patients was 39 years. Prevalence of ERC was 0.78% among males and 0.50% among females. The most affected teeth were the maxillary incisors and canines. The most frequent characteristics of the lesion were: extension up to the cervical third (47.5%), more than 270° circumferential spread (42.55%), probable pulpal involvement (57.5%), progressive stage (65%), supracrestal (52.1%) and mesial (34.7%) localization of >1 mm in size (52.1%) portals of entry. Cases with greater longitudinal involvement also showed greater circumferential progression (P = .008). There was no association between portal of entry location and bone crest or ECR reparative phase (P = .42). Inter-rater agreement ranged from good to very good. No association between portal of entry and ECR progression was observed.

CONCLUSIONS

ECR showed low prevalence in the Brazilian population, affecting mostly anterior maxillary teeth of patients within a wide age range. CBCT allowed characterization of ECR lesions with good interobserver agreement.

Prolonged application time effects on universal adhesives in non-carious cervical lesions: An 18-month split mouth randomized clinical trial

OBJECTIVE

This double-blind, split mouth randomized clinical trial aimed to assess the clinical performance of Clearfil Universal Bond Quick (CBUq) universal adhesive under different application times (no waiting and waiting) compared to Clearfil SE Bond adhesive in non-carious cervical lesions (NCCLs) over 18 months.

METHODS

One hundred and eighty-three restorations were distributed randomly into three groups based on the adhesive system and waiting time: CUBq without waiting time (CUBq-NW), CUBq with a 20 s waiting time (CUBq-W), and CSE with a 20 s waiting time. After placement, restorations were evaluated after 18 months using the International Dental Federation (FDI) and United States Public Health Service (USPHS) criteria. Statistical analyses involved Friedman repeated measures analysis of variance and Wilcoxon tests, with a significance level set at 5 %.

RESULTS

Over the 18-month period, no restorations were lost across the tested groups. Marginal adaptation evaluation indicated minor discrepancies in 21 restorations (8 CUBq-NW, 6 CUBq-W, and 7 CSE). There were no significant differences observed among the three groups following the 18-month clinical assessment (p > 0.05). Only two restorations showed marginal discoloration after 18 months (1 CUBq-NW and 1 CSE).

CONCLUSIONS

The application of Clearfil Universal Bond Quick using either the "waiting" or "no-waiting" technique exhibited excellent clinical results in NCCLs during the 18-month follow-up period, demonstrating comparable performance to Clearfil SE Bond in all assessed outcomes.

CLINICAL SIGNIFICANCE

The findings suggest that the new universal adhesive applied using the no-waiting technique demonstrates promising clinical performance when compared to conventional application methods.

TRIAL REGISTRATION

ClinicalTrials.gov identifer RBR-69p7mpr.

Clinical performance of non-carious cervical lesions restored with using self-etch mode of adhesives according to the FDI criteria

AIM

The purpose of this study was to evaluate the 18-month retrospective study of self-etch adhesive (Prime&Bond One Select) and self-etch mode of universal adhesives (Single Bond Universal, Gluma Bond Universal) applied to non-carious cervical lesions according to the World Dental Federation criteria.

MATERIALS AND METHODS

Thirty patients without any systemic disease, good oral hygiene, having at least 20 teeth and six non-carious cervical lesions treated using a self-etch mode of adhesives operated between January and March 2017. Accordingly, 335 restorations were evaluated according to the World Dental Federation criteria at 3, 6, 12 and 18 months. Pillai's Trace test was used to determine the interaction of criteria with time and adhesive systems. IBM SPSS Statistics 21.0 program was used in the analysis. Value of P < 0.05 was accepted as a criterion for statistical significance.

RESULTS

At the end of 18 months, participation was 100%. There was a statistically significant difference P < 0.05 between Prime&Bond One Select and Single Bond Universal, Prime&Bond One Select and Gluma Bond Universal in the 18-month period. In terms of marginal staining, fracture of material and retention, recurrence of caries, erosion and abfraction, tooth integrity criteria at the end of the 18 months, Prime&Bond One Select performed clinically very good, Single Bond Universal and Gluma Bond Universal performed clinically good according to World Dental Federation criteria. Marginal adaptation criteria, Prime&Bond One Select, Single Bond Universal and Gluma Bond Universal performed clinically good. Retention loss rate was found to be the lowest in Prime&Bond One Select and the highest in Gluma Bond Universal.

CONCLUSION

Accordingly, 18-month evaluation of all adhesives used in the study showed clinically acceptable results in all of the World Dental Federation criteria.

Clinical management of external cervical resorption: A systematic review

This review investigated whether any therapeutic options influenced the outcome of treatment for teeth with external cervical resorption. Out of 870 articles identified by an electronic search, 60 clinical case reports and six case series were included. No randomised clinical trials were found. Risk of bias was assessed using Joanna Briggs Institute's tools. External surgical intervention was the preferred method of accessing the lesions. Removal of resorptive tissue was most often achieved mechanically. Bioactive endodontic cements were the preferred materials for restoring teeth. The outcome measures were based on clinical and radiographic parameters. Of the cases included in the review, no specific treatment approach had a superior outcome in relation to Heithersay's classification. Furthermore, due to the absence of randomised clinical trials, and the low level of evidence associated with case reports/case series, it was not possible to define the optimum clinical treatment for external cervical resorption.

Clinical and radiographic features of external cervical resorption - An observational study

AIM

To determine the prevalence of symptoms, clinical signs and radiographic presentation of external cervical resorption (ECR).

METHODOLOGY

This study involved 215 ECR lesions in 194 patients referred to the Endodontic postgraduate Unit at King's College London or Specialist Endodontic practice (London, UK). The clinical and radiographic findings (periapical [PA] and cone beam computed tomography [CBCT]) were readily accessible for evaluation. A checklist was used for data collection. Inferential analysis was carried out to determine if there was any potential association between type and location of tooth in the jaw as well as sex, age of the patient and ECR presentation and radiographic feature.

RESULTS

Eighty-eight patients (94 teeth) were female and 106 patients were male (121 teeth), the mean age (±SD) was 41.5 (±17.7) years. Fifteen patients (7.7%) had more than one ECR lesion. The most affected teeth were maxillary central incisors (21.4% [46 teeth]) and mandibular first molars (10.2% [22 teeth]). ECR was most commonly detected as an incidental radiographic finding in 58.1% [125 teeth] of the cases. ECR presented with symptoms of pulpal/periapical disease in 23.3% [n = 50] and clinical signs (e.g. pink spot, cavitation) in 16.7% [36 teeth] of the cases. Clinical signs such as cavitation (14%), pink spot (5.1%) and discolouration (2.8%) were uncommon, but their incidence increased up to 24.7% when combined with other clinical findings. ECR was detected in the resorptive and reparative phases in 70.2% and 29.8% of the cases respectively.

CONCLUSION

ECR appears to be quiescent in nature, the majority being asymptomatic and diagnosed incidentally from PA or CBCT. When assessed with the Patel classification, most lesions were minimal to moderate in relation to their height (1 or 2) and circumferential spread (A or B). However, the majority of ECRs were in (close) proximity to the pulp. Symptoms and clinical signs were associated with (probable) pulp involvement rather than the height and circumferential spread of the lesion. Clinical signs were more frequently associated when ECR affected multiple surfaces.

Investigating the etiology of non-carious cervical lesions: Novel µCT analysis

OBJECTIVES

The etiology of non-carious cervical lesions (NCCLs) is not fully understood, limiting treatment and prevention. Our aim was to evaluate the effect of mechanical loading and acid exposure on the cervical tooth region using a random spectrum loading model that simulates the nature of oral mastication.

METHODS

Thirty extracted human premolars were divided into three experimental groups: 1) unloaded teeth immersed in acid (erosion group: Er), 2) loaded teeth immersed in acid (erosion with spectrum loading group: Er-SL), and 3) loaded teeth immersed in distilled water (spectrum loading group: SL). Random spectrum loading with loads ranging from 100 to 500 N was performed. All teeth were scanned using micro-CT. A novel 3D analysis was developed to evaluate the circumferential cervical tissue loss and regions under tension and compression. For parametric and non-parametric comparisons, one-way ANOVA with Tukey post-hoc tests and Kruskal-Wallis with Bonferroni post-hoc tests were used.

RESULTS

A significant difference was observed in the circumferential volumetric loss, with the Er-SL exhibiting the greatest volume loss (p < 0.001). Moreover, in the loaded groups (Er-SL and SL), regions subjected to tension showed significantly greater loss (p < 0.001, p = 0.007) compared with regions subjected to compression.

CONCLUSIONS

The novel high-resolution micro-CT analysis provided new insights into the etiology of NCCLs. The results suggested that the cumulative effect of mechanical loading and acid exposure may play a major role in NCCL formation.

CLINICAL SIGNIFICANCE

This study investigates the etiology of NCCLs by examining the combined effects of occlusal loads and acid exposure on cervical tissue loss. Understanding the pathogenesis of NCCLs paves the way for the development of improved preventative measures and treatment strategies to prevent tooth structure degradation.

A qualitative analysis of dentists' understanding and management of non-carious cervical lesions (NCCL)

INTRODUCTION

Non-carious cervical lesions (NCCLs) are considered to have a multi-factorial aetiology and their management is affected by a range of variables perhaps most importantly clinical judgement. The aim of this study was to elicit information from practicing dentists, using interviews, to explore their understanding of NCCL aetiology, the decision-making criteria of when to restore, and the restorative techniques used to restore NCCLs. This may help identify gaps or anomalies in our understanding to inform future research and clinical practice for the management of NCCLs.

METHODS

An interview guide was developed from a literature search which formed 2 domains framed around understanding and management of NCCLs based on: understanding of diagnosis and aetiology, and factors affecting decision making for management. Practicing dentists with more than 10 years of experience were purposively recruited to conduct in-depth, semi-structured interviews. Fifteen interviews were audio recorded and transcribed verbatim. A thematic content analysis was conducted and the results analysed.

RESULTS

From the thematic analysis, 2 domains were identified. In the domain of "diagnosis and aetiology", while participants have similar understanding and methods of diagnosing NCCL, most stated NCCLs in a patient were caused by a "main aetiology" such as "abrasion", "abfraction" while few described the inter-relationship of these aetiological factors. In the domain of "factors affecting decision making". "Patient reported symptoms" and "lesion dimension" were the main factors that affected participants' decision to provide restorative or non-restorative management. However, a "restorative threshold" was not able to be identified.

CONCLUSION

There was notable variety in participants' understanding of the aetiology, management, and treatment of NCCLs, particularly the restorative threshold of when to treat.

CLINICAL SIGNIFICANCE

The variability demonstrates the need to have a clearer understanding of the key elements that affect the management of NCCLs and better information to support the decision of when to treat.

Evaluation of a novel restorative protocol to treat non-carious cervical lesion associated with gingival recession: a 2-year follow-up randomized clinical trial

OBJECTIVE

To compare 2 different resin composites and 2 adhesive systems used in a new restorative protocol (partial restoration) to treat non-carious cervical lesions associated with gingival recession type 1 (RT1).

MATERIAL AND METHODS

Eighty combined defects (CDs) were treated with a partial restoration and periodontal plastic surgery for root coverage. The CDs were randomly assigned to one of the following groups: NP + TE (n = 20), nanofilled composite and 2-step total-etch adhesive system; NP + UA (n = 20), nanofilled composite and universal adhesive system; MH + TE (n = 20), microhybrid composite and 2-step total-etch adhesive; MH + UA (n = 20), microhybrid composite and universal adhesive. Restorations were assessed using the United States Public Health Service (USPHS) criteria at 1 week (baseline) and 6, 12, and 24 months. Survival rate, periodontal parameters, dentin hypersensitivity (DH), and aesthetics were also evaluated.

RESULTS

After 24 months, only the MH + TE group did not lose any restoration, with no significant differences between groups. For surface roughness parameter, MH presented 83.3% of the restorations scoring Bravo, whereas NP presented 48.5% of the restorations scoring Bravo. All groups presented restorations with marginal discoloration. All periodontal parameters behaved similarly, regardless of the restorative material. All groups presented significant reductions of dentin hypersensitivity and improved aesthetic perceptions (p < 0.05).

CONCLUSION

Both resin composites and adhesives tested can be combined for partial restorations to treat CDs.

CLINICAL RELEVANCE

This new restorative-surgical protocol to treat CDs presents satisfactory outcomes. The partial restorations can be successfully executed with both combinations of adhesives and resin composites evaluated in this investigation. TRN : ClinicalTrial.gov: NCT03215615; registration date July 12, 2017.

Origin and Development of Cervical Dentin Hypersensitivity and Noncarious Cervical Lesions: Literature Review

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.

Clinical Performance of a "No Wait" Universal Adhesive in Noncarious Cervical Lesions: A Two-year Randomized Controlled Clinical Trial

PURPOSE

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).

MATERIALS AND METHODS

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.

RESULTS

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 (p < 0.05). 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.

CONCLUSION

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.

Sixty-month follow up of three different universal adhesives used with a highly-filled flowable resin composite in the restoration of non-carious cervical lesion

OBJECTIVE

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.

MATERIAL AND METHODS

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.

RESULTS

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).

CONCLUSION

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.

TRIAL REGISTRATION

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.

Five-year Randomized Clinical Trial on the Performance of Two Etch-and-rinse Adhesives in Noncarious Cervical Lesions

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.

Machine learning to predict distal caries in mandibular second molars associated with impacted third molars

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.

Are Glass-Ionomer Cement Restorations in Cervical Lesions More Long-Lasting than Resin-based Composite Resins? A Systematic Review and Meta-Analysis

PURPOSE

To compare the the loss of retention and color match of glass-ionomer cements (GIC) and resin-based composites (RC) in noncarious cervical lesions. Other secondary outcomes (surface texture, marginal adaptation, marginal discoloration, and secondary caries) were evaluated in a systematic review and meta-analysis.

MATERIALS AND METHODS

A comprehensive search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, and Cochrane. We included only randomized clinical trials. The quality of the evidence for each outcome was assessed using the GRADE tool.

RESULTS

A total of 1530 articles were identified, but only 19 reports remained for analysis, all of which were judged to possess "unclear" risk of bias. GIC showed higher retention rates in all follow-ups (1 to 3 years, p < 0.0001; at 5 years, p < 0.00001). No difference was observed for marginal discoloration, marginal adaptation and secondary caries in all follow-ups (p > 0.05). RC showed better color match than GIC only at 2 years (p = 0.03). Higher roughness was observed in GIC in all follow-ups (at 1 year p = 0.0003; at 3 years p = 0.0004). Quality of evidence was graded as moderate or low due to unclear risk of bias and imprecision in some outcomes.

CONCLUSION

The loss of retention of RMGIC/GIC was inferior to that of RC, but a higher roughness was observed in the RMGIC/GIC when compared to RC in all follow-ups of the clinical studies evaluated. In addition, the color match was better with RC only in the 2-year follow-up when compared to GIC. The quality of evidence was judged as moderate to low in these two outcomes.

Decision-making process as guide to the management of non-carious cervical lesions with and without painful symptomatology

The aim of this study is to develop a decision-making path for the management of non-carious cervical lesions (NCCLs) associated with or without dentin hypersensitivity (DH) This will allow to limit or delay invasive approaches identifying the causes that produced them. The need for this review is because there are no clear guidelines in the current literature for the treatment of NCCLs. Usually, the selection of the best therapy option is postponed to clinical judgment which can be influenced by a patient's demands (aesthetic, symptomatologic reasons or worsening of pre-existing NCCL). To establish a therapeutic plan the young dentist should be able to distinguish the NCCLs that need to be monitored over time from those in need of early treatment. Indeed, the experience of the dentist and the compliance of the patient play a decisive role for the success of the therapy.

Nonsurgical Management and 2-year Follow-up by means of Cone Beam Computed Tomography of an Invasive Cervical Resorption in a Molar

BACKGROUND

Invasive cervical resorption (ICR) is a relatively uncommon form of external tooth resorption, characterized by an invasive nature. It is usually painless and detection of lesions is often made incidentally. Three-dimensional imaging techniques, such as cone beam computed tomography (CBCT), are useful in the diagnosis and management of ICR as the true extent of the defect cannot always be estimated using conventional radiographs.

AIM

The aim of this article is to report on the successful treatment of ICR in mandibular first molar by nonsurgical approach and follow-up by means of CBCT.

CASE REPORT

An 18-year-old patient was referred with a complaint of unusual radiolucency in the mesial cervical area of tooth #19 with unknown etiology. Cone beam computed tomography was performed to assess the extent of the lesion in three spatial levels and diagnosis of Heithersay class III ICR was made. This case presented with ICR (Heithersay class III) on tooth #19. Nonsurgical root canal treatment and removal of the lesion from the coronal access was performed; the resorptive defect was filled with dual-cure, self-adhesive, resin-modified glass ionomer cement (RMGIC); 6-month follow-up X-ray film showed no changes at the lesion site and tooth was asymptomatic; 1-year follow-up X-ray film showed slight mesial bone loss and a probing depth of 3 mm; finally, 2-year follow-up CBCT images showed no recurrence and no further bone destruction at the lesion site.

CONCLUSION

The intraoral radiographs revealed the resorptive changes in two dimensions; therefore, the actual extent and location of the lesions are not fully understood. On the contrary, CBCT is a very useful tool to achieve a proper diagnosis; it detects the extent of the defect more accurately and hence, improves the treatment outcomes of ICR.

CLINICAL SIGNIFICANCE

The ICR is usually seen as a late complication to traumatic injuries of the teeth; it is essential, therefore, that the patients who were exposed to situations that can damage the integrity of periodontal tissue need to have careful periodic recalls and X-ray examinations.

Periodontal Evaluation in Noncarious Cervical Lesions Restored with Resin-modified Glass-Ionomer Cement and Resin Composite: A Randomised Controlled Study

PURPOSE

To assess periodontal parameters of noncarious cervical lesions (NCCLs) restored with glass-ionomer cement (RM-GIC) and composite resin at baseline, three and six months.

MATERIALS AND METHODS

Eighteen patients with bilateral lesions were included in the study. Lesions (1 mm in depth) were randomly restored with each type of restorative material. Probing depth (PD), relative gingival recession (rGR), relative clinical attachment level (rCAL), visible plaque index (VPI) and gingival bleeding index (GBI) were measured.

RESULTS

No statistically significant differences were found when comparing within groups (p > 0.05). However, the intergroup analysis demonstrated a decrease in GR and rCAL gain for teeth restored with the resin-modified glass-ionomer cement (RM-GIC).

CONCLUSION

Both materials behaved similarly when in close contact with periodontal tissues and did not influence periodontal parameters.

Management of bilateral invasive cervical resorption lesions in maxillary incisors using a novel calcium silicate-based cement: A case report

Invasive cervical resorption is a pathologic process leading to progressive and usually destructive loss of tooth structure. The pathogenic mechanism is not completely understood and the diagnosis may be challenging. The aim of this article is to present an unusual case of bilateral presence of invasive cervical resorption lesions in maxillary central incisors and to discuss the treatment procedures using a novel repair material. The management of the present case was carried out in three phases. The first stage of the treatment aimed at curetting the active tissue from the resorption cavity and restoring the defect with the novel calcium silicate-based cement (Biodentine, Septodont). In the maxillary left central incisor it was not possible to remove the resorptive tissue without exposing the pulp, and therefore root canal treatment was performed. At the second phase, a full-thickness flap was raised in order to expose and repair the defect that was extending subgingivally. At the third phase teeth were restored with composite resin. The patient was kept under review and after a follow-up period of 2 years neither signs of periradicular lesion nor recurrence of resorption were observed. The teeth were asymptomatic, and restorations appeared to be in excellent condition. In conclusion, Biodentine seems to be a promising material for the treatment of invasive cervical resorption lesions.

External Cervical Resorption: A New Oral Manifestation of Systemic Sclerosis

Systemic sclerosis (SSc) is a complex, chronic, and progressive autoimmune disease. SSc causes bone resorption of mandible and distal phalanges of fingers through a known mechanism, and it has also been pointed out as a possible cause of apical root resorption of teeth, because tooth resorption is regulated by similar mechanisms to those controlling bone resorption. The objective of this article was to report the first case in the literature of external cervical resorption (ECR) as an oral manifestation of SSc. A 66-year-old female patient with a 35-year history of SSc was diagnosed with multiple ECRs through a computerized axial tomography and clinical examination. All known causes of ECR were discarded after a detailed anamnesis and clinical examination. This report details SSc as a possible cause of ECR and discusses the pathogenesis of ECR in relation with SSc. The systemic alterations provoked by SSc can be related to the etiopathogenesis of cervical root resorption. It is extremely relevant that dental care providers be aware that external cervical resorptions could be present in patients suffering from SSc, consciously look for these lesions, treat them early in case they are present, and advise the patient with SSc of the importance of continuous dental controls.

Stress-strain Analysis of Premolars With Non-carious Cervical Lesions: Influence of Restorative Material, Loading Direction and Mechanical Fatigue

Noncarious cervical lesions (NCCLs) are characterized by a loss of dental structure at the cementoenamel junction (CEJ) caused by stress, biocorrosion, and attrition. Variations in occlusal loading can promote different stress and strain patterns on the CEJ. Restoration of NCCLs is part of lesion management; however, there is still no conclusive restorative protocol for NCCLs. This study aimed to evaluate the stress and strain distribution of maxillary premolars with NCCLs according to three factors: 1) restorative technique; 2) direction of occlusal loading; and 3) mechanical fatigue. Three-dimensional (3D) finite element analysis (FEA) and strain gauge testing were used to assess stress and strain, respectively. 3D-FEA orthotropic, linear, and elastic models were generated: sound tooth (SO); unrestored NCCL; or NCCL restored with glass ionomer; flowable composite resin; nanofilled composite resin (CR); lithium disilicate ceramic; and nanofilled composite resin core associated with a lithium disilicate laminate (CL). A 150-N compressive static load was applied in two conditions: axially in both cusps (Al); and at a 45° angle to the long axis of the tooth applied to the palatine cusp (Ol). For the experimental tests, specimens were treated as described previously, and one strain gauge was attached to the buccal surface of each tooth to record tooth strains before and after cyclic loading (200,000 cycles, 50 N). FEA showed that the association of NCCL and Ol resulted in higher stress values. CR and CL restorations showed the closest biomechanical behavior to SO for both loading types. Loaded Al or Ol specimens showed higher strain values after mechanical fatigue. Lower stress and strain were observed with Al when compared with Ol. The restoration of NCCLs with composite resin only or associated with ceramic laminates seems to be the best approach because the results for those groups were similar in biomechanical behaviors to sound teeth.

Abrasion: A Common Dental Problem Revisited

Dental abrasion is most commonly seen at the cervical necks of teeth, but can occur in any area, even inter-dentally from vigorous and incorrect use of dental floss. Acid erosion has been implicated in the initiation and progress of the cervical lesion, while tooth-brush abrasion has long been held as the prime cause of cervical abrasion. Identification of the risk factors is clearly important in order to modify any habits and provide appropriate advice.

[Effect of molar ligation and local Porphyromonas gingivalis inoculation on alveolar bone loss in the mouse]

OBJECTIVE

To compare the extent and time course of alveolar bone loss and osteoclast activation in two murine models of periodontal disease: molar ligation and Porphyromonas gingivalis (P. gingivalis) oral inoculation.

METHODS

A split-mouth design was applied to two groups of mice (C57BL6, 6-8 weeks old, n=24 in both groups), resulting in four treatment groups: (1) Control group: unligated upper right 2nd molars receiving CMC only, (2)Ligature group: ligation of a 9-0 suture around the upper left 2nd molar, (3) P. gingivalis group: unligated upper right 2nd molar receiving P. gingivalis challenge only, (4)Ligature+P.gingivalis group: ligation of the upper left 2nd molar in combination with oral inoculation with 109 colony-forming units(CFU) P. gingivalis. Alveolar bone loss was measured as the cementoenamel junction and alveolar bone crest (CEJ-ABC) distance. In the study, 48 C57BL6 mice were designed and treated as described above, and osteoclasts were counted on histological sections following tartrate-resistant acid phosphatase (TRAP) staining and counts were normalized to alveolar bone surface distance. Then 36 C57BL6 mice were investigated, of which 30 were ligated a 9-0 silk ligature around the 2nd molar in the left maxillary quadrant and 6 were not ligated. After ligation for 1 week, the ligatures in 12 mice were taken off for either 1 week or 2 weeks. The CEJ-ABC distance of the 6 mice without ligation was baseline. The CEJ-ABC distances were measured and analyzed. The data were analyzed with one-way ANOVA.

RESULTS

Molar ligation induced marked alveolar bone loss after 3, 6, 9 and 12 weeks [(0.16±0.04) mm, (0.16±0.02) mm, (0.18±0.03) mm, (0.17±0.02) mm], vs. corresponding controls [(0.09±0.03)mm,(0.10±0.01)mm,(0.12±0.04)mm,(0.12±0.01)mm] and P. gingivalis group [(0.09±0.03)mm, (0.12±0.01)mm,(0.12±0.02)mm,(0.10±0.01)mm], P<0.05. Combined treatment with molar ligation and P. gingivalis did not further increase the CEJ-ABC distance. Evidence for osteoclast activation was found one day after molar ligation, and TRAP-positive cell numbers peaked on day 3 (12±4 vs. control 2±2, P<0.01). After taking off ligature following ligation for 2 weeks, it showed significantly regrowth of alveolar bone compared with that before removal of the ligature on day 7 [(0.07±0.02)mm vs. (0.13±0.01)mm, P<0.01].

CONCLUSION

Molar ligation is a rapid and effective way to induce periodontal bone loss in mice. Osteoclast activation occurs within 24 hours of ligature placement, and the extent of bone loss well exceeds that of the P.gingivalis-induced bone loss. Removing ligature after periodontal disease might help bone regeneration by regrowth of the alveolar bone.

Potential of desensitizing toothpastes to reduce the hydrogen peroxide diffusion in teeth with cervical lesions

PURPOSE

To evaluate the occlusive potential of four toothpastes by atomic force microscopy (AFM) before and after bleaching and quantify the hydrogen peroxide (HP) diffusion into the pulp chamber after application of desensitizing toothpastes in teeth with cervical lesions.

METHODS

In 52 human extracted premolars, 2-mm deep artificial cervical lesions (ACL) were prepared and rinsed with EDTA for 10 seconds. Then teeth were adapted in a brushing machine and brushed with one of the following toothpastes [Regular toothpaste with no occlusive compounds Colgate Cavity Protection (CP), Oral-B Pro Health (OB), Colgate ProRelief (PR) and Sensodyne Rapid Relief (RR)] under constant loading (250 g; 4.5 cycles/seconds; 3 minutes). In 13 teeth (control group), no artificial cervical lesion was prepared. After that, the teeth were bleached with 35% HP with three 15-minute applications. The HP diffusion was measured spectrophotometrically as a stable red product based on HP reaction with 4-aminoanthipyrine and phenol in presence of peroxidase, at a wavelength of 510 nm and the dentin surfaces of ACL were evaluated before and after bleaching by AFM. Data was statistically analyzed by one-way ANOVA and Tukey's test (alpha = 0.05).

RESULTS

In the AFM images, some modifications of the dentin surface were observed after application of OB and RR. However, only for RR the formation of a surface deposit was produced, which occluded the majority of the dentin tubules. Also, only for RR, this deposit was not modified/removed by bleaching. Despite this, all groups with ACL showed higher HP penetration than sound teeth, regardless of the toothpaste used (P < 0.001).

No association between gingival labial recession and facial type

OBJECTIVE

To evaluate if facial type is a predictor of the development of gingival recession.

METHODS

A cohort of 179 orthodontic patients (76 males, 101 females; age before treatment T S = 12.4 years, SD = 0.8) were followed until 5 years post-treatment (T 5 = 20.7 years, SD = 1.2). The presence of recessions was scored ('Yes' or 'No') by two raters on initial (T S), end of treatment (T 0), and post-treatment (T 5) plaster models. A recession was noted (scored 'Yes') if the labial cemento-enamel junction was exposed. The clinical crown heights were measured at T S, T 0, and T 5 as the distances between the incisal edges and the deepest points of the curvature of the vestibulo-gingival margins. Determination of the facial type was based on the inclination of mandibular plane relative to cranial base (Sella-Nasion/Mandibular Plane) and the proportion of posterior to anterior face heights (PFHs; SGo/NMe × 100 per cent) on pre-treatment cephalograms.

RESULTS

From T 0 to T 5, the number of subjects with recessions increased from 2 (1.1 per cent) to 24 (13.6 per cent), and the number of recession sites increased from 2 to 39. However, most patients had either one or two recession sites. The mean clinical crown height of mandibular incisors increased by 0.86mm (SD = 0.82, P < 0.001). Regression analysis showed that mandibular plane inclination had no effect on the development of gingival recession or on the increase of clinical crown heights of mandibular incisors.

CONCLUSIONS

Facial type is not a predictor of the occurrence of gingival recession.

Meta-Analysis of the Influence of Bonding Parameters on the Clinical Outcome of Tooth-colored Cervical Restorations

PURPOSE

To meta-analyze the literature on the clinical performance of Class V restorations to assess the factors that influence retention, marginal integrity, and marginal discoloration of cervical lesions restored with composite resins, glass-ionomer-cement-based materials [glass-ionomer cement (GIC) and resin-modified glass ionomers (RMGICs)], and polyacid-modified resin composites (PMRC).

MATERIALS AND METHODS

The English literature was searched (MEDLINE and SCOPUS) for prospective clinical trials on cervical restorations with an observation period of at least 18 months. The studies had to report about retention, marginal discoloration, marginal integrity, and marginal caries and include a description of the operative technique (beveling of enamel, roughening of dentin, type of isolation). Eighty-one studies involving 185 experiments for 47 adhesives matched the inclusion criteria. The statistical analysis was carried out by using the following linear mixed model: log (-log (Y /100)) = β + α log(T ) + error with β = log(λ), where β is a summary measure of the non-linear deterioration occurring in each experiment, including a random study effect.

RESULTS

On average, 12.3% of the cervical restorations were lost, 27.9% exhibited marginal discoloration, and 34.6% exhibited deterioration of marginal integrity after 5 years. The calculation of the clinical index was 17.4% of failures after 5 years and 32.3% after 8 years. A higher variability was found for retention loss and marginal discoloration. Hardly any secondary caries lesions were detected, even in the experiments with a follow-up time longer than 8 years. Restorations placed using rubber-dam in teeth whose dentin was roughened showed a statistically significantly higher retention rate than those placed in teeth with unprepared dentin or without rubber-dam (p < 0.05). However, enamel beveling had no influence on any of the examined variables. Significant differences were found between pairs of adhesive systems and also between pairs of classes of adhesive systems. One-step self-etching had a significantly worse clinically index than two-step self-etching and three-step etch-and-rinse (p = 0.026 and p = 0.002, respectively).

CONCLUSION

The clinical performance is significantly influenced by the type of adhesive system and/or the adhesive class to which the system belongs. Whether the dentin/enamel is roughened or not and whether rubberdam isolation is used or not also significantly influenced the clinical performance. Composite resin restorations placed with two-step self-etching and three-step etch-and-rinse adhesive systems should be preferred over onestep self-etching adhesive systems, GIC-based materials, and PMRCs.

One-year Clinical Evaluation of Resin Composite Restorations of Noncarious Cervical Lesions in Smokers

PURPOSE

To evaluate the one-year clinical performance of composite restorations in noncarious cervical lesions placed in smoking and non-smokers using a multimode adhesive system with two adhesive strategies.

MATERIALS AND METHODS

Among the selected cervical lesions, four experimental groups were formed based on the patients' smoking habit and bonding strategies with a multimode adhesive system (n = 38): G1: etchand- rinse in non-smokers; G2: selective enamel etching in non-smokers; G3: etch-and-rinse in smokers; G4: selective enamel etching in smokers. The restorations were paired, ie, each patient received at least two restorations. A nanofilled resin composite was applied and light cured incrementally in all groups by one operator. Two calibrated examiners evaluated the restorations at baseline, 6 and 12 months after placement. The modified USPHS criteria were used for evaluation. Data were analyzed using the chi-square (for associations between groups) and McNemar tests.

RESULTS

No statistically significant difference was found between groups for the criteria of retention, marginal discoloration, color match, marginal integrity, or sensitivity after 6 and 12 months. The assessments over time showed a statistically significant difference only for marginal discoloration at 12 months for groups 1, 3, and 4 when compared to baseline (p = 0.031). There were no statistical differences for any criteria evaluated among smokers and non-smokers, except for color match, where a difference was found after the baseline evaluation. Regarding the adhesive strategy, etch-and-rinse resulted in a clinical performance similar to that of selective enamel etching over 12 months.

CONCLUSION

Neither cigarette smoking habit nor adhesive strategy influenced the clinical performance of resin composite cervical restorations over the first year.

Effect of Remaining Cavity Wall, Cervical Dentin, and Post on Fracture Resistance of Endodontically Treated, Composite Restored Premolars

PURPOSE

The aim of this study was to examine the effect of remaining buccal cavity wall, remaining cervical tissue, and post on the fracture strength of endodontically treated restored premolars.

MATERIALS AND METHODS

Teeth were randomly allocated to 10 experimental groups (n=10) according to cavity design and presence or absence of post or to a control group. After thermal and mechanical aging, ramped loading until fracture was performed.

RESULTS

A high cervical outline (417 N) and the presence of a post (189 N) increased fracture strength, but both factors together had an antagonistic effect of -218 N, resulting in a higher strength of not 606 N (417+189) but 388 N. The risk of catastrophic failure increased (OR=3.17) when a post was present.

Combined orthodontic-periodontal treatment in periodontal patients with anteriorly displaced incisors

INTRODUCTION

Flared and elongated incisors are associated with different types of periodontal bone defects, usually horizontal. Combined orthodontic-periodontal treatment is being used in periodontal patients with anterior displacement of the incisors. The purpose of this study was to investigate the changes in periodontal health and the shape of bone defects in the incisors after such combined treatment.

METHODS

Fourteen adults were included in the study. In total, 56 elongated maxillary incisors with horizontal bone defects received orthodontic-periodontal treatment with circumferential supracrestal fibrotomy. To improve bone morphology, periodontal regenerative surgery and guided tissue regeneration were performed on the anterior teeth with angular bone defects after orthodontic treatment. Cone-beam computed tomography scans were taken before treatment (T0), at the end of the orthodontic intrusion (T1), and 6 months after the guided tissue regeneration surgery (T2). Probing pocket depth and clinical attachment loss were examined at T0, T1, and T2. The data were analyzed using paired t tests.

RESULTS

From T0 to T1, clinical attachment loss decreased significantly by 0.29 mm (P <0.05). The distance from the cementoenamel junction to the marginal bone crest decreased by 0.66 mm (P <0.05). The labial side of alveolar bone thickness increased by 0.54 mm (P <0.05), and the lingual side of alveolar bone thickness decreased by 0.46 mm (P <0.05). The shape of the bone defect was changed from horizontal to vertical on some teeth. From T1 to T2, both probing pocket depth and clinical attachment loss improved significantly, and the radiographic examinations showed bone redepositions of 2.15 ± 0.68 mm (P <0.05) vertically and 1.44 ± 0.92 mm (P <0.05) horizontally. The distance from the most apical point of the bone defect to the cementoenamel junction after combined treatment decreased by 2.11 ± 1.30 mm (P <0.05).

CONCLUSIONS

Combined orthodontic-periodontal treatment improved the periodontal conditions of the defective bone sites. Bone morphology, altered by orthodontic intrusion with fibrotomy, can improve the results of subsequent guided tissue regeneration.

Dental Materials: What Goes Where? Class V Restorations

A large number of Class V restorations are placed per annum to restore cervical lesions. This paper evaluates the pathogenesis of these lesions, with particular reference to the role of occlusal factors, and reviews the literature in order to provide advice on the material(s) which are most likely to produce optimal longevity of a Class V restoration. CPD/CLINICAL RELEVANCE: Resin-modified glass ionomer materials appear to provide optimal survival for a Class V restoration, but a (flowable) comDosite miaht Droduce a better aesthetic result.

Influence of operator experience on non-carious cervical lesion restorations: Clinical evaluation with different adhesive systems

PURPOSE

To evaluate the influence of operator experience on adhesive technique and to assess the clinical performances of two different adhesive systems.

METHODS

90 cervical lesions in 42 subjects, with a mean age of 52.4 years (range between 32-63) were selected. Lesions were divided into two groups according to operator experience (n = 42 restorations performed by a skilled operator, n = 48 restorations performed by five unexperienced operators) and further divided into two subgroups according to the adhesive system used: three-step etch-and-rinse (Optibond FL) or one step self-etch (G-Bond). Adhesives were applied according to manufacturers' instructions. Subjects underwent follow-up at 12, 24, and 36 months and restoration retention, enamel and dentin marginal integrity, marginal discoloration, caries occurrence, post-operative sensitivity, and preservation of tooth vitality were evaluated according to USPSH criteria. ANOVA test was performed to evaluate the influence of the adhesive system, the operator experience, and aging on restorations.

RESULTS

Operator experience (expert vs. inexperienced), aging time (12, 24, or 36 months), and the adhesive system (self-etch vs. etch-and-rinse) all affected the results statistically, as did the interaction between the adhesive system and operator experience.

The Octagon Model: a clinical tool for assessing marginal tissue recession

The Octagon Model is a clinical assessment tool designed to assess marginal tissue recession (MTR) and estimate the level of difficulty in achieving root coverage. It evaluates eight patient- and siterelated factors: patient's expectations, smoking status, width of keratinized tissue, absence/presence of cervical lesion, interproximal soft tissue/bone level, depth and width of recession defect, and buccal bone thickness. The model is presented in a three-colored diagram to facilitate communication between clinicians and between clinicians and their patients, and to assist clinicians in optimizing treatment plans at both site and patient levels.

Full-mouth treatment of gingival recessions and noncarious cervical lesions with coronally advanced flap and xenogeneic collagen matrix: a 2-year case report

BACKGROUND

In clinical practice it is common to observe adjacent multiple gingival recessions (MGRs) associated with noncarious cervical lesions (NCCLs). The aim of this 2-year case report was to describe the full-mouth treatment of a patient affected by MGRs and NCCLs, with a combined restorative-surgical approach using a coronally advanced flap (CAF) and a xenogeneic collagen matrix (CM).

METHOD

Before surgery, a composite restoration filled the deepest portion of the NCCL defects and was finished at the level of the maximum root coverage (MRC). The surgical technique adopted for the root coverage procedures was CAF for MGRs without vertical releasing incisions in the maxilla, and with one vertical releasing incision in the mandible. The CM was positioned at the level of the cementoenamel junction (CEJ), and sutured at the base of the anatomic de-epithelialized papillae. The flap was shifted coronally, providing complete coverage of the CM, and sutured coronal to the CEJ with a variable number of sling sutures.

RESULTS

At 2 years, complete root coverage was achieved in all treated sites, and the patient reported complete resolution of dental hypersensitivity. In the questionnaire, the patient-reported outcome showed a high level of esthetic satisfaction (mean score: 9.6; range: 9 to 10), and the objective esthetic evaluation with the root coverage esthetic score (RES) system showed a very high result (mean: 9.4).

CONCLUSIONS

The suggested combined restorative-surgical approach provided successful root coverage and a favorable esthetic outcome in the treatment of MGR associated with NCCLs.

[Impacted teeth and the six incarnations of resorption]

There are six distinct types of resorption of dental hard tissue that occur in association with unerupted and impacted permanent teeth. These pathologic entities differ markedly from one another in terms of their aetiology, their treatment and their prognosis. In several of them, the continued existence of the affected tooth may be in danger while in others, conservative treatment may halt the resorption process and provide for a successful outcome. The treatment approach is specific for each type and is entirely dependant on the diagnosis. This presentation will discuss prevalence, aetiology, presenting symptoms and clinical signs, radiographic features, histopathology, differential diagnosis, treatment and prognosis in relation to each of the conditions.

Periodontal consequences of mandibular incisor proclination during presurgical orthodontic treatment in Class III malocclusion patients

OBJECTIVE

To test the hypothesis that periodontal changes are similar between proclined and minimal-changed mandibular incisor position groups during presurgical orthodontic treatment for Class III orthognathic surgery.

MATERIALS AND METHODS

The following measurements were performed before and after presurgical orthodontic treatment of 75 patients (proclination group, 39 subjects; minimal-change group, 36 subjects): clinical crown length, sulcus and bone probing depths, and width of attached gingiva from clinical examination; infradentale-to-MP (perpendicular distance of infradentale to mandibular plane) from examination of lateral cephalograms; and the distance between the cementoenamel junction and alveolar crest from examination of periapical radiographs. Data were compared between the two groups, and a regression analysis was performed to investigate factors affecting the periodontal changes.

RESULTS

In both groups, clinical crown length and bone probing depth increased during presurgical orthodontics (P < .05). Infradentale-to-MP and the width of attached gingiva decreased more in the proclination group than in the minimal-change group (P < .05). Proclination and protrusion of the mandibular incisors, and treatment duration affected the periodontal changes.

CONCLUSIONS

The null hypothesis was rejected. Proclination of the mandibular incisors for decompensation in Class III surgery patients seems to result in labial alveolar bone recession and a decrease in width of attached gingiva. However, the amount of the periodontal recession appeared to be clinically insignificant.

Rubber dam isolation--key to success in diastema closure technique with direct composite resin

The use of direct composite resin for diastema closure has technique advantages, including that the restorative procedure can be carried out in one appointment at a reasonable cost and without the removal of sound tooth structure. The use of a rubber dam for closing diastemas with composite resin is of paramount importance as it prevents moisture contamination and ensures increased gingival retraction compared to other techniques. This provides better access to the cervical area of the tooth, facilitating proper placement of resin to recreate the natural anatomical contours and contact point. Thus, there is a more natural adaptation of the restoration to the gingival tissue, avoiding a space between the papilla and the restored tooth. To illustrate the advantages of this technique, two diastema closure cases are presented using direct composite resin with rubber dam isolation.

Randomized clinical trial of four adhesion strategies in cervical lesions: 12-month results

The aim of this study was to evaluate the 6- and 12-month clinical performance of four adhesion strategies from the same manufacturer (Kerr) in non-carious cervical lesions (NCCLs) using two evaluation criteria. Thirty-five patients, with at least four NCCLs each, participated in this study. After samplesize calculation, 180 restorations were assigned to one of the following groups: OFL (Optibond FL), OSP (Optibond Solo Plus), XTR (Optibond XTR), and AIO (Optibond All-In-One). The composite resin Filtek Supreme Ultra (3M ESPE) was placed incrementally. The restorations were evaluated at baseline, after 6 months, and after 12 months, using both the FDI and the USPHS-modified criteria. Statistical analyses were performed with Friedman repeated measures, ANOVA by rank, and the McNemar test for significance in each pair (α=0.05). Six restorations (2 for OFL, 1 for OSP, 2 for XTR, and 1 for AIO) were lost at 12 months (P>0.05 for both evaluation criteria). Marginal staining was observed in seven restorations using the FDI criteria (P>0.05) and three restorations using the USPHSmodified criteria (P>0.05). Eight restorations (2 for OSP, 3 for XTR, and 3 for AIO) were classified as Bravo for marginal adaptation using the USPHSmodified criteria (P>0.05). However, 62 restorations (14 for OFL, 12 for OSP, 15 for XTR, and 21 for AIO) were classified as Bravo using the FDI criteria (P>0.05). The four adhesion strategies showed similar clinical retention at 6 and 12 months. The FDI evaluation criteria tend to be more sensitive than the USPHS-modified criteria.

Surgical repair of invasive cervical root resorption with calcium-enriched mixture cement: a case report

Invasive cervical resorption (ICR) occurs in the cervical area of the teeth due to the formation of a soft tissue that progressively resorbs dentin. The disease is asymptomatic unless the pulp is exposed. This article presents a case involving a mandibular canine that was treated with a calcium-enriched mixture (CEM) cement. After a full mucoperiosteal flap was performed, the soft tissue was curetted away and the cavity filled with CEM biomaterial. One week later, the supragingival surface of the CEM was polished and covered with composite resin. At a 1-year follow-up visit, the pulp was healthy and the gingival probing depth decreased from >3 mm to 1 mm, showing attachment gain. As a biocompatible material, CEM has proven its ability in dentinogenesis, cementogenesis, and osteogenesis; it may prove to be a suitable biomaterial for treating ICR cases.

Prevalence of non-carious cervical lesions and associated risk indicators in middle-aged and elderly populations in Southern China

OBJECTIVE

To explore the prevalence of NCCL and associated risk indicators in 35- to 44-year-olds and 65- to 74-year-olds from both urban and suburban districts of Guangzhou, Southern China.

METHODS

A cross-sectional survey was conducted on NCCL with a sample of 768 35- to 44-year-olds and 991 65- to 74-year-olds, and the Tooth wear index was applied to record the tooth wear. Data on socioeconomic status, health behaviour and general health condition were obtained from a structured questionnaire.

RESULTS

The prevalence of NCCL was 76.8% and 81.3% in middle-aged and elderly populations, respectively. The results from the analysis of covariance (ANCOVA) demonstrated that for the 35- to 44-year-olds, those who were male, older, living in the suburban district and used toothpicks frequently, they tended to have more teeth with NCCL. Men, who were aged between 65 and 74 years old, who used toothpicks frequently, drank vinegar beverages, ate hard food and had not visited a dentist in a year; tended to have more teeth with NCCL.

CONCLUSION

NCCL was very common amongst middle-aged and elderly populations in South China. Older men who had unhealthy oral habits like using toothpicks, eating hard food and drinking vinegar beverages tended to have more teeth with NCCL. Oral health education would benefit those at risk.

Stain Removal Assessment of Two Manual Toothbrushes with an Interproximal Tooth Stain Index

OBJECTIVE

To assess a newly developed index to measure interproximal stain and evaluate the stain removal efficacy of two commercially available manual toothbrushes.

METHODS

This was a randomized, examiner-blind, parallel-group, two-treatment clinical trial of two weeks' duration. Subjects qualified for the study if they had an average Modified Lobene Stain Index of ≥ 1.5 from two anterior teeth. At baseline, subjects brushed in front of a mirror for one minute under supervision. All subjects were provided with a standard 0.243% sodium fluoride dentifrice and were randomly assigned either an Oral-B Pulsar manual brush (OBP) or a Colgate Whitening manual brush (CW) to use for two weeks. Stain was reassessed after two weeks of product use. Stain measurements were conducted using the Modified Lobene Stain Index and the new Interproximal Modified Lobene Stain Index, which allows for assessment of stain in hard-to-reach areas using the same area and intensity scales as the Modified Lobene Stain Index.

RESULTS

Use of the two manual brushes resulted in statistically significant reductions in surface stain relative to baseline after two weeks of use. Median stain reductions were 78% and 60% for the OBP and CW, respectively, as measured by the Modified Lobene Stain Index. The mean changes in the composite scores from baseline to week two were 1.85 and 1.57 for the two treatment groups, respectively. Statistically significant reductions from baseline were also found for the intensity and extent of stain measures (p < 0.001). Similar trends were found using the new Interproximal Modified Lobene Index. Composite median stain removal percentages versus baseline were 88% and 73% for the OBP and CW groups, respectively (p < 0.001). For the interproximal sites, a median stain removal of 92% was observed with the OBP brush and 83% reduction with the CW brush. For the gingival sites, the median stain removal percentages were 83% and 50%, respectively For the body region, a median stain removal of 100% was found for both treatment groups. No statistically significant differences were found between the two groups for the mean composite scores for either index.

CONCLUSION

Both manual brushes showed effective stain removal, including interproximal hard-to-reach sites. The Interproximal Modified Lobene Stain Index gave clinically relevant results consistent with the traditional Modified Lobene Stain Index, while allowing assessment of interproximal regions.

Restorations in abrasion/erosion cervical lesions: 8-year results of a triple blind randomized controlled trial

PURPOSE

An equivalence randomized controlled trial within the subject was organized to evaluate the clinical long-term success of a new 2-step etch & rinse adhesive and a new nano-filled ormocer.

METHODS

50 subjects, 21 males and 29 females aged between 21 and 65, were randomized to receive 150 restorations, 100 with the new restorative material, 50 with the composite as control, placed in non-carious cervical lesions with the same bonding system. The main outcome measure was the cause of failure at 8 years. Randomization was number table-generated, with allocation concealment by opaque sequentially numbered sealed and stapled envelopes. Subjects, examiner, and analyst were blinded to group assignment. Two interim analyses were performed. Data were analyzed by ANOVA and Cox test (P < 0.05).

RESULTS

After 8 years, 40 subjects and 120 teeth were included in the analysis of the primary outcome. There were eight failures in the experimental group and four failures in the control group. The cumulative loss rate was 7% for both restorative materials, with the annual failure lower than 1%, without any statistically significant difference. There were two key elements of failure: the presence of sclerotic dentin and the relationship between lesion and gingival margin.

Esthetic evaluation of different approaches to treat gingival recession associated with non-carious cervical lesion treatment: a 2-year follow-up

PURPOSE

To evaluate the esthetic outcome of four different approaches to treat gingival recession, associated with non-carious cervical lesion (combined defects) and the possible roles of patient-related factors in this esthetic outcome.

METHODS

78 combined defects were previously treated by: coronally advanced flap (CAF), CAF plus cervical restoration using resin-modified glass-ionomer material (CAF+R), connective tissue graft (CTG) and CTG+R. After a follow-up of 2 years, esthetic evaluations were performed using a modification of the Root Coverage Esthetic Score (MRES) and Qualitative Cosmetic Evaluation (QCE). Additionally, regression analyses were performed to evaluate the influence of patient-related factors in the final esthetic outcome.

RESULTS

The MRES showed that CAF and CTG had statistically significantly better results, when compared to the other groups (P < 0.05). Similarly, the QCE showed that CAF and CTG, along with CAF+R presented better results, and CTG+R showed the poorest esthetic outcome. Regression analyses showed that the overall gingival inflammation (full mouth bleeding index--FMBI) was negatively associated with CTG MRES score (P = 0.04 and R = -0.48). This means that the greater the FMBI during the study period, the lower the final esthetic score.

Bizarre tooth surface loss and the Miswak stick

Tooth surface loss can present in a variety of ways, some of which can appear rather strange on first examination. This case report demonstrates an unusual presentation of tooth surface loss (TSL) and its subsequent treatment. This loss of hard dental tissue appeared to be affecting the whole of the patient's remaining dentition, both lingually and buccally. Detailed questioning revealed the origins of this problem which turned out to be due to excessive use of an intra-oral Miswak chewing stick. Cinical Relevance: This article will enable clinicians to understand the importance of specific, targeted history-taking, involving a rare case of tooth surface loss as well as the use of minimally destructive restoration composites and a fibre-reinforced composite bridge.