Non-carious Cervical Lesions Research Articles

Low-level laser therapy in cases of dentin hypersensitivity

Dentin hypersensitivity is characterized by short, sharp pain in response to a stimulus – thermal, drying, tactile, osmotic or chemical. These stimuli cause an unpleasant sensation lasting from seconds to minutes after provocation. Many alternative treatment methods have been introduced. One of the options is the use of low-level laser therapy, whose effect is based on the increase of the excitability threshold of the free nerve endings causing an analgesic effect, as well as on the stimulation of pulp mesenchymal cells to differentiate into odontoblasts and produce reparative dentin. To investigate the efficacy of low-level laser therapy in treating dentin hypersensitivity, we selected a group of patients complaining of sensitivity at the cervical area of teeth provoked by stimuli such as air, touch and cold spray. The patients were with good oral hygiene and with intact teeth or small non-carious cervical lesions. They confirmed the absence of serious systematic and psychological diseases; some of them smoked electronic cigarettes, which may aggravate the pain. The patients were submitted to six sessions of treatment of dentin hypersensitivity with intervals from 48 to 72 hours, as indicated by the manufacturer of the low-intensity laser device. The painful sensation was measured before each of the six sessions and immediately after the treatment. The results were evaluated by using a four-point scale. The answers assessment showed good results – there was a decrease of the pain sensation from 3-4 level to 1-2 level. Yet, we have to interpret this carefully, because pain evaluation is subjective and some of the smokers have quit smoking electronic cigarettes during the treatment. As a method of curing dentin hypersensitivity, the low-level laser therapy shows a good treatment efficacy, but needs further continuous follow-up.

A COMPARATIVE STUDY OF FREQUENCY OF RETENTION OF FLOWABLE NANOCLUSTER COMPOSITE AND RESIN MODIFIED GLASS IONOMERS IN NON CARIOUS CERVICAL LESIONS IN MAXILLARY MOLARS

Objective: To investigate and compare the retention rates of Flowable-Nanocluster-Composite and Resinmodified-Glass-Ionomers in non-carious cervical lesions in maxillary molars.
 Study Design: Prospective cross-sectional comparative study.
 Place and Duration of Study: Department of Operative Dentistry, Armed Forces Institute of Dentistry,Rawalpindi, from Jan 2017 to Dec 2018.
 Methodology: Male patients ranging from 30-40 years with moderate non-carious cervical lesions of maxillarypremolars and molars of either quadrant presenting to out-patient department were selected through convenience sampling. These lesions were restored with Flowable-Nanocluster-Composite and Resin-Modified-GlassIonomer. Retention of these two materials over the period of 6 months, 1 year and 2 years was noted. Chi square statistics were used to compare groups.
 Results: The retention of Flowable-Nanocluster-Composite was 92% in 6 months, 85% in one year and 81% in two years. Whereas, for resin-modified-glass-ionomer restorations, the frequency of retention of the filling material was 97% at 6 months, 93% at one year and 89% at two years period. Out of the total 74 resin-modified-glassionomers restorations, 8 (11%) had dislodged by the end of the second year as compared to 14 (19%) dislodged restorations for Flowable-Nanocluster-Composite.
 Conclusion: In conclusion, the study reveals that resin modified glass-ionomer has a superior retention rate over the period of two years as compared to Flowable-Nanocluster Composite. A dentist should have an insight into compositions of restorative materials for the longevity of their retention in various lesions.

Multidisciplinary Treatment of Deep Non‐Carious Cervical Lesion With a CAD/CAM Chairside Restoration in Combination With Periodontal Surgery: A 60‐Month Follow‐Up Technique Report

Restoring function and esthetics are essential aspects of periodontology and restorative dentistry. Depending on their extension and the tissues involved, the treatment of non-carious cervical lesions (NCCLs) associated with gingival recessions may require a multidisciplinary approach, and different periodontal and restorative techniques have been described. This case report presents an innovative approach to treat a deep NCCL combined with a gingival recession in a canine region of a female patient. A Computer Aided Design - Computer Aided Manufacturing (CAD/CAM) chairside ceramic restorations in combination with mucogingival surgery procedures are described. A comprehensive analysis of the selected approach and its clinical implications is presented based on a 60-month follow-up. Conclusions After 60-month follow-up, clinical condition maintained stable, and a successful esthetic outcome was accomplished. Complete root coverage was achieved and kept throughout the whole period of tracing.

Study of oral microorganisms contributing to non-carious cervical lesions via bacterial interaction and pH regulation.

There is a lack of evidence about the relationship between microorganisms and non‐carious cervical lesions (NCCLs) due to limited technologies. A group of 78 patients was enrolled for microbial 16S rRNA sequencing of dental plaques on normal and defective cervical surfaces. Parallel data from 39 patients were analysed with paired t tests, and Fusobacteriales exhibited significantly less distribution on NCCLs than on normal surfaces. As a result, Fusobacterium nucleatum, the most common oral bacterial strain belonging to the order Fusobacteriales, was selected for further research. From a scanning electron microscopy (SEM) scan, the tooth surface with Fusobacterium nucleatum and Streptococcus mutans culture was more intact than that without Fusobacterium nucleatum. Furthermore, the calcium contents in groups with Fusobacterium nucleatum were significantly higher than that without it. In further mechanistic research, Fusobacterium nucleatum was demonstrated to adhere to and disturb other organisms as well as producing alkaline secretions to neutralize the deleterious acidic environment, protecting the tooth structure. In conclusion, microorganisms and NCCLs were confirmed directly related through adherent bacterial interactions and pH regulation. The research provides a new perspective and experimental evidence for the relation between microorganisms and NCCLs, which guides clinical treatment and preventive dentistry in the future.

Dental hypersensitivity in individuals with cleft lip and palate: Origin and therapies

Background. Dental hypersensitivity is due to the exposure of the dentin layer after wear of enamel or cementum, exposing the dentinal tubules and the nerve endings of odontoblasts within these tubules. The present study aimed to assess the factors related to dental hypersensitivity in individuals with cleft lip and palate and the most common therapy received. Methods. The medical records of 536 patients with cleft lip and/or palate (281 males, 255 females) with a mean age of 18 were analyzed in a single center. The inclusion criterion was patients reporting dental hypersensitivity from May 2015 to October 2019. The origin of dental hypersensitivity was evaluated considering orthodontic movement, periodontal diseases, and reversible and irreversible pulpitis. The therapy indicated by the dental professionals for dental hypersensitivity were recorded. Descriptive statistics were performed. Results. Of 61 teeth with dental hypersensitivity, 10 were attributed to orthodontic movement, 21 to periodontal problems, 27 to reversible pulpitis, and three to irreversible pulpitis. The most used therapies were the application of fluoride varnish and prophylaxis, dentifrice indication for dental sensitivity, free gingival grafts, pulpectomy, desensitizing agent application, conservative endodontic treatment (direct pulp protection), and restoration of non-carious cervical lesions. Conclusion. Reversible pulpitis was the most prevalent etiologic factor of dental hypersensitivity in individuals with cleft lip and palate. Dentifrices for dental sensitivity and fluoride varnish application were frequently recommended.

Factors Associated with Noncarious Cervical Lesions in Different Age Ranges: A Cross-sectional Study.

Objectives Understanding the possible risk factors of noncarious cervical lesion (NCCL) is important for prevention and clinical management of the condition. The aim of this study was to investigate the factors associated with the prevalence of NCCL among adolescents, adults, and elderly people. Materials and Methods A cross-sectional study involving 501 participants aged 15 years or older was conducted. Participants were examined to assess the number of natural teeth and the prevalence and severity of NCCL by calibrated examiners. Data on age, gender, harmful toothbrushing habits, and acidogenic diet were collected through individual interviews. Multivariate Poisson’s regression models were used to evaluate the association between the independent variables and the prevalence of NCCL according to the three age groups: 15 to 39, 40 to 64, and 65 years or older. Results The prevalence of NCCL among participants was 62.5% (95% confidence interval: 58.2–66.7). Among 15- to 39-year-old participants, the mean of NCCL was higher in males, those with lower number of teeth and acidogenic diet intake. Males aged 40 to 64 years and those with harmful brushing habits were more likely to present higher mean of NCCL. Elderly people with harmful toothbrushing habits had a greater mean of NCCL. Conclusion Demographic (age and gender), clinical (number of teeth), and behavioral characteristics (harmful brushing habits and acidogenic diet) were meaningful factors associated with NCCL severity. The above-mentioned relationships varied between age groups.

Objective assessment of simulated non-carious cervical lesion by tridimensional digital scanning.

To explore the use of 3D intraoral scanner/image analysis for the detection and monitoring of simulated non-carious cervical lesions (NCCLs) in vitro. A total of 288 NCCLs of different severities and simulated using a laboratorial model associating toothbrush stiffness (soft, medium, and hard) and toothpaste abrasivity (low, medium, high, and negative control) were analyzed. Dental impressions were taken from specimens before and after 35K and 65K brushing strokes, and then scanned with a CEREC Omnicam scanner. 3D models were analyzed for volumetric tooth loss. 3D optical profilometry was considered as the gold standard. Data were analyzed using ANOVA and Fisher's PLSD tests (alpha = 0.05), and agreement between methods by using intraclass correlation coefficient. Toothbrushes of hard and mid stiffness caused higher tooth loss than soft when associated with the highest abrasive, at 35K and 65K strokes (p< 0.001). Variation in slurry abrasivity led to differences in tooth loss (with control < low < medium < high, p< 0.0001) after both 35K and 65K strokes, regardless of the type of toothbrush used, except at 35K, wherein control = low (p= 0.55). 35K strokes caused less tooth loss than 65K for all abrasive slurries (p < 0.0001) except controls. The intraclass correlation coefficient for agreement between the test and gold standard methods was 0.85. Analysis of 3D images from intraoral scanner could detect and monitor NCCL progression, although this ability was limited on incipient lesions. Overall good agreement was found between the test method and optical profilometry. The suggested method may be applicable to detect and monitor NCCLs clinically.

Diagnosis of non-carious cervical lesions

Diagnosis of non-carious cervical lesions

Prevalence of non-carious cervical lesions and cervical dentinary hypersensitivity in undergraduate students

Abstract Introduction The non-carious cervical lesion (NCCL) is currently a common oral disease. Objective This observational and descriptive study aimed to assess risk factors associated with non-carious cervical lesions, cervical dentin hypersensitivity (CDH), gingival recession (GR) and the relationship between these conditions in students in the last years of undergraduate dentistry. Material and method One hundred eighty-five dentistry students from a private college in Ceará with an average of 22.7 ± 2.3 years participated by filling out a google docs form. Two calibrated examiners performed the exams to verify the presence of NCCL, CDH and RG. Result The presence of NCCL was 22.7%, GR was 48.1% and cervical dentin hypersensitivity 8.6%. The chi-square test with p &lt; 0.05% verified a correlation between the presence of NCCL and the presence of GR and CDH. 25% of students had NCCL and 14% considered themselves stressed. There was no association between the variables bruxism and stress (p=0.529), bruxism and year of graduation course (p=0.716), as well as no association between stress and year of course (p = 0.397) was observed. There were no correlations between NCCL and bruxism, muscle symptoms, parafunctional habits and temporomandibular dysfunction. 10.8% of students who reported using legal and illegal drugs had NCCL. Conclusion The NCCL, GR and CDH were correlated in the group of students in the last two years of an undergraduate dentistry course in Ceará.

Scanning electron microscope characterization of noncarious cervical lesions in human teeth.

Aims:Abfraction is a theoretical process whereby occlusal forces create microfractures in enamel and dentin along the cervical area and predispose it to erosion and abrasion, forming noncarious cervical lesions. However, the theory is not yet proven. The aim of this study was to elucidate the role of abfraction as an etiology of these lesions.Materials and Methods:Ten human premolars with these lesions from 10 patients requiring tooth extraction, one tooth from each patient, were used in this study. After extractions, all teeth were stored in 10% formalin until required, then prepared routinely for scanning electron microscopy.Results:In all 10 teeth, at low magnification, noncarious cervical lesions appeared as crescent-shaped lesions. The upper edges of the lesions were on the enamel surfaces and their lower edges were on the cemental surfaces. In four teeth, the lesions showed evidence of microfractures characterized by the presence of fracture lines and fracture surfaces. In addition, in the first tooth of these teeth, the surface was also covered by a network of poorly fixed collagen fibers. In the third tooth, linear scratches, the openings of the dentinal tubules, a dentin matrix which consisted of a network of poorly fixed collagen fibers, and numerous dentinal tubules were also observed. In the remaining six teeth, they showed linear scratches, and the presence of the dentinal tubules or the exposed collagen fibers.Conclusions:It appears that abrasion and erosion are associated etiologic factors in forming noncarious cervical lesions and an ultrastructural finding that supports the abfraction theory of these lesions is observed.

Rethinking the decision-making process to treat gingival recession associated with non-carious cervical lesions.

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.

Presence of Gingival Recession or Noncarious Cervical Lesions on Teeth under Occlusal Trauma: A Systematic Review

AbstractThe goal of this research was to carry out a systematic review to verify the possible influence of occlusal factors on the occurrence of gingival recession and noncarious cervical lesions. To answer the specific research question—whether gingival recession or noncarious cervical lesions on teeth are present under occlusal trauma—a bibliographic search was conducted at MEDLINE/PubMed, Web of Science, and Gray Literature databases focusing on articles published, following strict inclusion criteria based on randomized clinical trials, controlled clinical studies, and case series, with restricted language (English) and publication date between March 2010 and March 2020, considering patients with occlusal trauma and gingival recession/noncarious cervical injuries. Questionnaires, animal or laboratory studies, case reports, and interviews were excluded. First, the title and/or abstract of the articles obtained were analyzed and, finally, a full-text reading was performed. Given the amount and diversity of the final studies, a qualitative analysis was made. Based on the established criteria, it was possible to obtain an initial 757 articles. After screening, five articles were included, and then qualitative analysis was performed. The results described in the articles were different, given the heterogeneity of the articles subjected to analysis. A few studies were published in the past 10 years, suggesting that the traumatic occlusion seems to be associated with the occurrence of the noncarious cervical lesion while it is not possible to arrive at a conclusion with regard to the association of gingival recession and occlusal trauma. Key Message Even though many professionals have categorically affirmed that there is a relation between trauma occlusal and gingival recession/noncarious cervical lesion, this systematic review found the absence of strong literature to really prove it. Once defined, it allows the therapeutic focus to centre on the causal or contributing factors and preventing or reducing future recurrence.

Three-year evaluation of different adhesion strategies in non-carious cervical lesion restorations: a randomized clinical trial.

:Objective:To evaluate non-carious cervical lesions (NCCLs) restored with different adhesion strategies.Methodology:This is a prospective, randomized, double-blind, split-mouth study. An adhesive restorative system (Single Bond Universal/Filtek Z350XT – SBU) was evaluated both without and with selective enamel conditioning (E-SBU), resin-modified glass-ionomer cements (Vitremer; RMGIC), and ethylenediaminetetraacetic acid pretreatment (EDTA; E-RMGIC). In total, 200 restorations, placed in 50 patients, were evaluated at baseline and at a 3-year follow-up using the modified United States Public Health Service (USPHS) criteria. Data were analyzed using the two-proportion equality test, multinomial logistic regression, Wilcoxon test, and Kaplan-Meier survival curves.Results:In total, 42 (84%) patients returned for the 3-year follow-up. SBU showed restoration losses statistically different from RMGIC. Retention was also statistically different in SBU between baseline and the 3-year follow-up. Marginal defects and surface texture were statistically significant for all groups in the period studied, except for the surface texture of SBU and the marginal integrity in E-RMGIC. We observed no statistically significant difference in wear, secondary caries, anatomical form, surface staining, and color over time. Recession degree was the only factor to influence retention rates. Cumulative survival (%) was 89, 98, 98, and 95.3, for SBU, SE-SBU, RMGIC, and E-RMGIC, respectively, without significant differences among them. There was a statistically significant difference between survival curves; however, multiple comparison procedures found no statistical differences.Conclusion:Selective enamel etching affected the retention of non-carious cervical restorations. Adhesion using EDTA and resin-modified glass-ionomer cements delayed marginal defects over time. The degree of gingival recession influenced retention rates. Resin composite restorations showed initial marginal defects, and ionomer restorations, reduced surface luster. EDTA pre-treatment followed by resin-modified glass-ionomer cements may be a promising adhesion strategy for NCCL restorations.

Tomada de arco facial e montagem de articulador semi-ajustável para diagnóstico oclusal – relato de caso

Objective: It consists of reporting a clinical case of taking a facial arch and assembling a semi-adjustable articulator (ASA) for occlusal diagnosis. Case report: A 22-year-old female patient sought dental care because she was sensitive to element 24. It was clinically observed that the patient had a non-carious cervical lesion. The patient showed a physiological occlusion and an unfavorable positioning of elements 22 and 23. Thus, an attempt was made to investigate the presence of abrasive and erosive habits, which were not reported by the patient. Thus, a clinical evaluation and model assembly in ASA was conducted to identify possible occlusal interference, which would be triggering such injury. The following figures report the clinical case, occlusal registration, taking the facial arch itself, removing the facial arch, angulation adjustments in the ASA, mounting the upper and lower model in the position of maximum usual intercuspation. Conclusion: The use of the semi-adjustable articulator and the facial arch contributed to the diagnosis, planning and treatment of the case. Therefore, these instruments must be part of the dental surgeon’s clinical practice in order to offer greater predictability during oral rehabilitation.

18-Month Clinical Comparison of Giomer Based and Nano Technology Based Materials in Non-Carious Cervical Lesion Class V Restorations

The 18-month randomized, controlled, split mouth, clinical trial have been completed. Visits include: screening, restoration placement, 6 month follow-up and 18-month follow-up. Cervical lesions were restored with giomer based BEAUTIFIL II LS (SHOFU, Kyoto, Japan) (BL) or nano technology based Filtek™ Supreme (3M, St. Paul, MN) (FS). Restorations were placed following the manufacturer’s guidelines. Clinical assessments were done by blinded examiners excluding the examiner that placed the restorations. Restorations were evaluated according to clinical criteria by Hickel, et al. including esthetic properties (surface luster, surface staining, marginal staining, color match, anatomical form), functional properties (fracture of material and retention, marginal adaptation, patient’s view) and biologic properties (recurrence of caries, tooth integrity, adjacent mucosa). The Wilcoxon signed-rank test was used to compare the Hickel criteria between groups. Hickel scores were analyzed using the Wilcoxon signed-rank test. The Wilcoxon signed-rank test compared differences between the two groups (BL - FS) within the same subject and then ranked the differences. Only positive and negative ranks were used in the analysis. The established null hypothesis: BL and FS will perform equally in Hickel Scoring (H0: BL = FS) was not rejected as no Hickel criteria comparisons showed statistical significances. Clinical performance comparison of non-carious cervical lesion restorations between giomer and nano technology based restorative systems showed no statistical differences according to Hickel criteria with similar clinical evaluations for both restorative materials.

Effect of dentifrice slurry abrasivity and erosive challenge on simulated non-carious cervical lesions development in vitro.

To investigate the effect of slurry abrasive levels and acidic challenges on the development of non-carious cervical lesions. Ninety-six extracted upper premolars were affixed in pairs to acrylic blocks and had their root surfaces covered by acrylic resin except for 2 mm from the cemento-enamel junction. The specimens were distributed into six groups (n = 8 pairs) based on two experimental factors: (1) slurry abrasivity level [low/medium/high] and (2) citric acid challenge [yes/no]. Specimens were brushed for 5,000, 15,000, 35,000, and 65,000 strokes. Volume loss (VL) was determined based on optical profilometry scans of specimens impressions at the baseline and at subsequent brushing levels. Data were analyzed using repeated measures analysis of variance and Bonferroni pairwise comparison (α = 0.05). Higher VL values were associated with high-abrasivity slurries relative to low- and medium-abrasivity slurries (P < 0.001). Increasing the slurry abrasivity level increased the VL regardless of the acidic challenge, which did not have a significant effect (P = 0.184). After 65,000 strokes, significant VL was recorded in all groups relative to preceding brushing levels (P < 0.001). Higher values of time-dependent surface loss were associated with increased dentifrice slurry abrasivity, regardless of the citric acid challenge.

Prevalence of gingival recession and its correlation with gingival phenotype in mandibular incisors region of orthodontically treated female patients: A cross-sectional study.

Background:Gingival recession is associated with dentin hypersensitivity, unesthetic appearance, and carious or noncarious cervical lesions. Orthodontic treatment, gingival thickness (GT), and keratinized tissue width (KTW) play roles in gingival recession etiology. The study is aimed to compare the prevalence of gingival recession in the mandibular incisor region of orthodontically-treated females with untreated controls, and to identify if there is any correlation among the GT, KTW, and gingival recession.Subjects and Methods:A total of 150 Saudi females were enrolled in this study. They were categorized into the treatment group (n = 75) and control group (n = 75). Background characteristics and clinical periodontal parameters including the plaque index, gingival index, GT, KTW, gingival recession length (GRL), and gingival recession width (GRW) were recorded and compared between groups, and any associations were identified.Results:Among the orthodontically-treated females, 31 (41.33%) had at least one mandibular incisor with gingival recession, in contrast to 18 (24%) of the controls. Pearson's correlation analysis indicated a significant positive correlation between the GT and KTW and between the GRL and GRW (P < 0.001). In addition, a significant negative correlation was observed between the KTW and GRL and between the KTW and GRW (P < 0.001). However, no significant correlation was found between the GT and GRL or between the GT and GRW.Conclusions:Our findings indicated that orthodontic treatment is a predisposing factor for the development or progression of gingival recession, particularly in females with a narrow KTW.

Influence of viscosity and chemical composition of composite resins in non-carious cervical restorations: 12-month randomized clinical trial

Objective: The objective of this double-blind, randomized controlled clinical trial was to evaluate the clinicalperformance of two methacrylate-based flowable composite and ormocer-based flowable composite in non-cariouscervical lesions (NCCLs) of adult patients. Material and Methods: 183 restorations were performed on NCCLsusing the Futurabond U adhesive system, applied in the selective enamel etching mode in all cavities. After theadhesive application, the cavities were restored with one out of the three evaluated flowable composites (n = 61per group): ormocer-based flowable composite (Admira Fusion Flow, ORM), low viscosity methacrylate-basedcomposite (GrandioSO Flow, LV) and high viscosity methacrylate-based composite (GrandioSO Heavy Flow, HV).After 12 months of clinical performance, these restorations were evaluated according to FDI and USPHS criteriain the following items: retention/fracture, marginal adaptation, marginal staining, postoperative sensitivity andcaries recurrence. Results: eight restorations were lost/fractured after 12 months of clinical evaluation (1 inthe ORM and 7 in the HV group). The retention rates for 12- months (95% confidence interval) were 98.4%(91.3%-99.7%) for the ORM group, 100% (94.5%-100%) for the LV group and 88.5% (78.1%-94.3%) for theHV group, with no statistical difference identified between any pair of groups (p &gt; 0.05). Five restorationspresented small marginal adaptation defects at the 12-months evaluation recall, and all of them were consideredclinically acceptable. Conclusion: The clinical performance of the universal adhesive associated to ormocer-basedor methacrylate-based flowable composite were found to be promising after 12-month of clinical evaluation.KEYWORDSDental bonding; Dental restoration; Clinical trial.

FEATURES OF DENTINE CHEMICAL COMPOSITION OF INTACT TEETH AND TEETH WITH WEDGE-SHAPED DEFECTS

The aim: Is to define dentine chemical composition of intact teeth and those with wedge-shaped defects followed by the analysis of revealed differences. Materials and methods: Longitudinal sections of 22 clinically removed teeth (12 – clinically intact ones, 10 – with wedge-shaped defects) from both jaws were studied in patients aged between 25-54 years. JSM-6490 LV focused beam electron microscope (scanning) with system of energy-dispersive X-ray microanalysis INCA Penta FETх3 was used. The chemical composition of 148 dentine areas in the incisal region (tubercle), equator, cervical area has been determined as a percentage of the weight amounts of carbon, oxygen, calcium, phosphorus, sodium, magnesium, sulfur, chlorine, zinc, potassium, aluminum. Results: Dentine chemical composition of teeth with wedge-shaped defects differed from those of intact teeth by significantly lower content: sodium, chlorine and calcium – in the incisal region (tubercle); sodium, magnesium − at the equator; sodium, chlorine and calcium – in the cervical region (p≤0.05). In the sample groups with cervical pathology there was more sulfur and oxygen in the incisal region (tubercle), phosphorus and zinc – at the equator, carbon and potassium – in the cervical region (p≤0.05). Conclusions: Differences in the chemical composition of intact teeth and teeth with wedge-shaped defects, the presence of correlation between the studied chemical elements confirm the role of macro- and microelements in the pathogenesis of non-carious cervical lesions.

Comparative evaluation of two different isolation techniques in restoration of noncarious cervical lesions using flowable composite: A split-mouth in vivo study

Context: Proper method of isolation plays a key role in the restoration of noncarious cervical lesions (NCCLs). Aims: The aim of this in vivo study was to compare the efficacy of two isolation techniques in restoring NCCLs using flowable composite. Settings and Design: Forty patients who fulfill the inclusion criteria were selected based on the power of the study (0.86). The participants were divided into two groups according to the split-mouth design. Materials and Methods: In Group A, lesion isolation was done using the Mylar matrix band with photocurable gingival barrier, and in Group B, using Metal matrix band and gingival barrier. The restorations were assessed immediately and after 6 months, using modified US Public Health Service criteria: marginal integrity, marginal discoloration, wear, retention, secondary caries, and postoperative sensitivity. Statistical Analysis: IBM SPSS (version 21.0) software was used. McNemar's and Chi-square tests were performed, considering P Results: Both the groups demonstrated satisfactory clinical performance. Upon inter- and intragroup comparison of the two isolation methods, there was no statistically significant difference (P > 0.05). Conclusions: Within the limitations of the study, both the groups performed similarly in isolation of NCCLs. However, long-term clinical studies must be needed for further evaluation.