Retention of tooth-colored restorations in non-carious cervical lesions--a systematic review

A 2-Year Randomized Clinical Trial of Three Bonding Techniques in Non-Carious Cervical Lesions

Background and objective: The aim of this randomized split-mouth study-controlled clinical trial was to compare the 2-year clinical performance of resin composite restorations placed at non-caries cervical lesions (NCCL) with one-step self-etch, total-etch, and selective enamel etch and self-etch adhesive techniques. Materials and methods: Thirty-two patients received three resin composite restorations each at NCCLs (Tetric EvoCeram/Ivoclar/Vivadent), bonded with a total-etch adhesive agent (ExciTE F/Ivoclar/Vivadent) and a self-etch (AdheSE One F/Ivoclar/Vivadent) without and with selective enamel etching. All restorations were evaluated by two examiners at baseline, 6-, 12-, 18-, and 24-months with FDI clinical criteria (post-operation regarding retention, caries occurrence, marginal adaptation, and marginal staining). A logistic regression analysis, a Cohen's kappa statistic, a multifactorial analysis, and X2 were performed with generalized estimating equations. Results: After 2 years, the retention rate was 86.8% for total etch, 92.26% for self-etch, and 93.63% for selective enamel etching and self-etch. No caries was detected on the restorations. Concerning marginal adaptation, the clinically perfect restorations were 26.9% for the total-etch technique, 16% for self-etch, and 25.9% for selective enamel etch and self-etch. The logistic regression model revealed that only time reduced the probability of perfect marginal adaptation. Conclusions: All three adhesive strategies provided restorations with no significant differences in the retention rate or marginal adaptation, whereas the total etch yielded better performance for marginal staining. All restorations were assessed as clinically acceptable after 2 years.

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.

Retrospective Clinical Evaluation of RMGIC/GIC Class V Restorations

The aim of this retrospective study was to evaluate the clinical performance of glass-ionomer cement (GIC) and resin-modified glass-ionomer cement (RMGIC) materials in Class V carious cervical lesions restored by dental students. Ninety-six (96) restorations performed with either GIC (Fuji IX) (n = 39) or RMGIC (Fuji II LC) (n = 57) were evaluated using the modified USPHS criteria by two independent investigators at two follow-up evaluations (two years apart). The Fisher statistical test was used to compare USPHS criteria and examine significant differences, with a significance level set at p < 0.05. The Kaplan-Meier algorithm was used to calculate the survival probability. The overall success rate of Class V restorations was 72.9% at the second follow-up evaluation, with restorations ranging in age from 2.5 to 3.5 years. The RMGIC (Fuji II LC) restorations exhibited a significantly higher overall success rate compared to the GIC (Fuji IX) restorations (p = 0.0104). Significant differences were observed in retention (p = 0.0034) and color match (p = 0.0023).

Stereomicroscopic Aspects of Non-Carious Cervical Lesions

Non-carious cervical lesions (NCCLs) represent a form of tooth wear, characterized by the irreversible loss of dental hard tissues at the enamel-cement junction, without the involvement of caries and dental trauma. The aim of this study was to highlight the morphological elements of NCCLs via their stereomicroscopic examination and to confirm the role of this examination in the diagnosis of early lesions. In addition, the association between the morphological aspects identified during the stereomicroscopic examination of NCCLs and their etiological factors was determined. For this study, extracted teeth with NCCLs were examined with a stereomicroscope. The morphological aspects of NCCLs were evaluated at magnifications up to 75×. In wedge-shaped NCCLs, the stereomicroscopic examination allowed the identification and measurement of scratches, furrows and cracks. In saucer-shaped NCCLs, the stereomicroscopic examination highlighted the smooth appearance of the walls. The presented study highlighted the role of stereomicroscopic examination in the assessment of NCCL morphology and in their early diagnosis. The study confirmed, in particular, the role of occlusal overloads and tooth brushing in determining the morphology of NCCLs.

Conservative Treatment of Dental Non-Carious Cervical Lesions: A Scoping Review

This scoping review aims to evaluate methods of conservative reconstruction of dental enamel lesions resulting from abrasions and evaluate the effect of diode laser in reducing the symptoms of tooth sensitivity. The cementoenamel junction is more prone to substance loss because the enamel thickness is substantially decreased, resulting in a much weaker enamel-dentin bond.

METHODS

Dental abrasion was examined in the mechanical cause alone. Pubmed, Scopus, and Web of Science were used to discover publications that matched our topic from 1 January 2018 to 20 March 2023. A comparison of various non-carious cervical lesion (NCCL) restoration treatments was generated mostly by mechanical considerations.

RESULTS

A final number of 11 clinical trials and randomized controlled trials were included in the review for qualitative analysis. Composite resins performed well in clinical trials for the restoration of NCCLs.

CONCLUSIONS

Composite, in its different forms of filling and consistency, preceded by the use of adhesives, is an efficient and effective material for the treatment of NCCLs. Diode laser use prior to NCCL restoration of teeth does not diminish restoration retention rate, may lessen hypersensitivity, and may affect restoration success.

Noncarious cervical lesions: Morphology and progression, prevalence, etiology, pathophysiology, and clinical guidelines for restoration

PURPOSE

To synthesize the literature regarding noncarious cervical lesions (NCCLs) and propose clinical guidelines when lesion restoration is indicated.

MATERIAL AND METHODS

A PubMed search was performed related to NCCL morphology, progression, prevalence, etiology, pathophysiology, and restoration.

RESULTS

NCCLs form as either rounded (saucerlike) depressions with smooth, featureless surfaces that progress mainly in height or as V-shaped indentations that increase in both height and depth. Prevalence ranges from less than 10% to over 90% and increases with age. Common locations are the facial surfaces of maxillary premolars. They have a multifactorial etiology due to personal habits such as excessive horizontal toothbrushing and consumption of acidic foods and drinks. Occlusal factors have been identified as contributing to the prevalence of NCCLs in some studies, whereas other studies indicate there is no relationship. The concept of abfraction has been proposed whereby mechanical stress from occlusal loading plays a role in the development and progression of NCCLs with publications supporting the concept and others indicating it lacks the required clinical documentation. Regardless of the development mechanism, demineralization occurs and they are one of the most common demineralization diseases in the body. Treatment should be managed conservatively through preventive intervention with restorative treatment delayed until it becomes necessary due to factors such as lesion progression, impact on patient's quality of life, sensitivity, poor esthetics, and food collection may necessitate restoration. Composite resins are commonly used to restore NCCLs although other materials such as glass ionomer and resin-modified glass ionomer are also used. Sclerotic dentin does not etch like normal dentin and therefore it has been recommended to texture the dentin surface with a fine rotary diamond instrument to improve restoration retention. Some clinicians use mechanical retention to increase retention. Beveling of enamel is used to increase the bonding area and retention as well as enhance the esthetic result by gradually creating a color change between the restoration and tooth. Both multistep and single-step adhesives have been used. Dentin etching should be increased to 30 seconds due to the sclerotic dentin with the adhesive agent applied using a light scrubbing motion for 20 seconds but without excessive force that induces substantial bending of a disposable applicator. Both flowable and sculptable composite resins have been successfully used with some clinicians applying and polymerizing a layer of flowable composite resin and then adding an external layer of sculptable composite resin to provide enhanced resistance to wear. When caries is present, silver diamine fluoride has been used to arrest the caries rather than restore the lesion.

CONCLUSIONS

Noncarious cervical lesions (NCCLs) form as smooth saucerlike depressions or as V-shaped notches. Prevalence values as high as 90% and as low as 10% have been reported due to habits such as excessive toothbrushing and an acidic diet. Occlusal factors have been proposed as contributing to their presence but it remains controversial. Publications have both supported and challenged the concept of abfraction. They are one of the most common demineralization diseases in the body. Conservative treatment through prevention is recommended with restorative treatment delayed as long as possible. When treatment is needed, composite resins are commonly used with proposed restorative guidelines including texturing the sclerotic dentin, beveling the enamel, potential use of mechanical retention, 30 seconds of acid etching, and use of either multistep or single-step adhesives in conjunction with a light scrubbing motion for 20 seconds without excessive force placed on disposable applicators.

Effect of partial restorative treatment on stress distributions in non-carious cervical lesions: a three-dimensional finite element analysis

BACKGROUND

Partial restoration combined with periodontal root coverage surgery can be applied to the treatment of non-carious cervical lesions (NCCLs) accompanied with gingival recessions in clinical practice. However, the feasibility of NCCL partial restorative treatment from a biomechanical perspective remains unclear. This study aimed to investigate the effect of partial restorations on stress distributions in the NCCLs of mandibular first premolars via three-dimensional finite element analysis.

METHODS

Three-dimensional finite element models of buccal wedge-shaped NCCLs in various locations of a defected zenith (0 mm, 1 mm, and 2 mm) were constructed and divided into three groups (A, B, and C). Three partially restored NCCL models with different locations of the lower restoration border (1 mm, 1.5 mm, and 2 mm), and one completely restored NCCL model were further constructed for each group. The following restorative materials were used in all restoration models: composite resin (CR), glass-ionomer cement (GIC), and mineral trioxide aggregate (MTA). The first principal stress distributions under buccal oblique loads of 100 N were analyzed. Restoration bond failures were also evaluated based on stress distributions at dentin-restoration interfaces.

RESULTS

When the partial restoration fully covered the defected zenith, the first principal stress around the zenith decreased and the maximum tensile stress was concentrated at the lower restoration border. When the partial restoration did not cover the defected zenith, the first principal stress distribution patterns were similar to those in unrestored models, with the maximum tensile stress remaining concentrated at the zenith. As the elastic modulus of the restorative material was altered, the stress distributions at the interface were not obviously changed. Restoration bond failures were not observed in CR, but occurred in GIC and MTA in most models.

CONCLUSIONS

Partial restorations that fully covered defected zeniths improved the stress distributions in NCCLs, while the stress distributions were unchanged or worsened under other circumstances. CR was the optimal material for partial restorations compared to GIC and MTA.

Evaluation of the Mechanical Properties of Three Resin-Modified Glass-Ionomer Materials

This study is aimed at evaluating the flexural strength (FS), fracture toughness (FT), and diametral tensile strength (DTS) of three resin-modified glass-ionomer cements (RMGICs): Ketac Nano, Riva Light Cure, and Fuji II LC. One hundred twenty specimens were prepared from the RMGIC materials ( $n=10$ ). The cements were mixed and inserted into different mould sizes according to the test performed: FS: rectangular Teflon mould ( $32\text{mm}\times 3.15\text{mm}\times 2\text{mm}$ ); FT: notchless triangular prism (NTP) Teflon mould ( $6\text{mm}\times 6\text{mm}\times 6\text{mm}\times 12\text{mm}$ ); and DTS: ring road stainless steel mould ( $6\text{mm}\times 3\text{mm}$ ). Specimens were light cured for 20 seconds on each surface and stored in distilled water at ${37}^{°}\text{C}\pm 2^{°}\text{C}$ for seven days prior to tests. To evaluate the influence of storage in the mechanical properties of the RMGIs, specimens tested for DTS were stored in distilled water at ${37}^{°}\text{C}\pm 2^{°}\text{C}$ for 32 days prior to test. Data were analyzed by ANOVA and Tukey’s test ( $\alpha =0.05$ ). Fuji II LC presented significantly higher values for all tests employed when compared to Ketac Nano and Riva LC RMGIs. There was no significant difference on DTS before and after the 32-day storage for each material. Fuji II LC presented superior mechanical properties when compared to Ketac Nano, and Riva LC storage showed no influence on the mechanical properties of the RMGI materials tested.

Eight-year clinical evaluation of two types of resin composite in non-carious cervical lesions

OBJECTIVES

In this clinical study, the 8-year clinical performances of a flowable resin composite was compared with that of a conventional resin composite.

MATERIALS AND METHODS

Ninety non-carious cervical lesions (NCCLs) in 19 participants were involved in this trial. NCCLs were restored with a flowable composite (Clearfil Flow FX: FX, Kuraray Noritake, Japan) or a conventional resin composite (Clearfil AP-X: AP) in conjunction with a one-step self-etch adhesive (Clearfil S3 Bond). Each participant had both types of resin composite restorations that were randomly allocated. The restorations were evaluated at baseline and annually up to 8 years using modified USPHS criteria. The data were statistically analyzed using the Fisher's exact test, Kaplan-Meier method, and a multivariate Cox-regression with frailty models (p < 0.05).

RESULTS

The 8-year participant recall rate was 95%. One hundred percent retention was recorded for AP, whereas four out of 46 restorations were lost for FX during the 8 years. The incidence of marginal staining increased over time regardless of the type of resin composite, showing 48% for AP and 57% for FX after 8 years. Wear of the resin composite occurred only for the flowable material and there was a significant difference between the types of resin composite (p = 0.024). Overall survival rates at 8 years for AP and FX were 98% and 82% respectively (p = 0.110).

CONCLUSIONS

The flowable resin composite presented lower wear resistance and showed a lower survival rate compared with the conventional composite after eight years of clinical service.

CLINICAL RELEVANCE

Flowable resin composites may show greater wear after long-term clinical service.

TRIAL REGISTRATION NUMBER

UMIN000028745, Date of registration: August 19, 2017.

X-ray microtomography analysis of gaps and voids in the restoration of non-carious cervical lesions with different composite resins

Context (Background)

Resin composites are the most widely used material for restoring cervical defects. However, the high failure rate of these restorations is still a concern.

Aims

The aim of this in vitro study was to evaluate, using microtomography (μCT), the interfacial gap and voids formation in Class V cavities in premolars restored with materials with lower polymerization shrinkage combined with different restorative techniques.

Settings and Design

Cervical defects were created in 30 intact premolar and were randomly distributed to be restored by one of the following techniques (n = 6): Composite resin with two increments (CR), organic modified polymer (ORMOCER) with single (OR1) or two increments (OR2, or low viscosity bulk-fill composite resin with single (BF1) or two increments (BF2).

Methods and Material

Each tooth was scanned before filling to determine the volume of interest (VOI) to be applied in the second μCT after restoration and to control the cavity volume among the groups. In the μCT after filling, the volume of interfacial gaps and voids was calculated for each group.

Statistical Analysis

The groups were compared using one-way and Tukey HSD post hoc test (α = 0.05).

Results

It was possible to identify higher gap formation in the OR1 group and higher void formation in CR group (P < 0.05). OR2 group showed better results than the group with one increment. BF2 showed the best filling capacity.

Conclusions

It was possible to conclude that the material and the number of increments directly influenced the internal adaptation and voids formation of Class V restorations.

Challenging the Concept that OptiBond FL and Clearfil SE Bond in NCCLs Are Gold Standard Adhesives: A Systematic Review and Meta-analysis

PURPOSE

The following PICO (Patient/Population, Intervention, Comparison, and Outcomes) question was proposed: "Are retention rates of composite resin restorations in noncarious cervical lesions (NCCLs) when using adhesives considered "gold standard" (OptiBond FL and Clearfil SE Bond) higher than those obtained with other adhesives brands"?

METHODS

A search was performed in February 2019 (updated in November 2019) in the PubMed/MEDLINE, EMBASE, LILACS, BBO, Web of Science, Cochrane Library, Grey Literature, and IADR abstracts (1990-2018); unpublished and ongoing trial registries, dissertations, and theses were also searched. Only randomized clinical trials (RCTs) conducted in NCCLs that compared either OptiBond FL or Clearfil SE Bond adhesive with other commercially available adhesives were included. The risk of bias (RoB) was applied by using the Cochrane Collaboration tool. A meta-analysis was performed for retention rates at different follow-up times using a random effects model for both the adhesives. Heterogeneity was assessed with the Cochran Q test and I2 statistics. Grading of Recommendations: Assessment, Development and Evaluation (GRADE) assessed the quality of evidence.

RESULTS

After removal of duplicates and noneligible articles, 25 studies remained for qualitative synthesis, as one study was common to the two adhesives, of which 9 studies were used for the OptiBond FL meta-analysis and 14 for the Clearfil SE Bond meta-analysis. No significant differences were observed for retention rates in follow-up periods of 12-24 months (p=0.97), 36-48 months (p=0.72), or 108-156 months (p=0.73) for OptiBond FL; and for 12-24 months (p=0.10) and 36-48 months (p=0.17) for Clearfil SE Bond. A significant difference was only found for OptiBond FL at 60-96 months (p=0.02), but only three studies were included in this meta-analysis.

CONCLUSIONS

The evidence from available RCTs conducted in NCCLs that compared OptiBond FL or Clearfil SE Bond does not support the widespread concept that these adhesives are better than any other competitive brands available in the dental market.

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.

Two-year randomized clinical trial of different restorative techniques in non-carious cervical lesions and MMP activity in gingival crevicular fluid

OBJECTIVES

To evaluate different restorative techniques for non-carious cervical lesions (NCCLs) and the activity of matrix metalloproteinases (MMPs) in gingival crevicular fluid.

MATERIALS AND METHODS

Two hundred restorations were performed in 50 patients using resin composite restorative system without (I) and with selective enamel conditioning (II) and resin-modified glass-ionomer cement without (III) and with EDTA pretreatment (IV). Gingival crevicular fluid samples were collected in 15 patients. Restorations were evaluated using USPHS criteria at baseline and after 2 years. Percentages of MMP activity were assessed by zymography as a surrogate outcome. Equality tests of two proportions, logistic regression analysis, survival analysis, ANOVA repeated measures, and Fisher tests were used.

RESULTS

No differences in clinical performance were found among groups. Group I had lower retention at 2 years than at baseline. Decreased alpha scores for marginal integrity and marginal discoloration were observed for all groups after 2 years. MMP-2 decreased after 1 year, and its activity increased back to the initial level after 2 years, mainly for groups I, II, and III. MMP-9 increased after 1 year, and it was reduced to the initial level after 2 years, mainly for group I.

CONCLUSIONS

All restorative techniques performed similarly in NCCLs after 2 years with initial marginal defect alterations. MMP-2 reestablished its initial levels after 2 years, and MMP-9 had few alterations over time in crevicular fluid. Clinical relevance The different restorative techniques are equally successful in NCCLs after 2 years of clinical functioning and have similar effects on MMPs present in crevicular fluid.

Glass hybrid versus composite for non-carious cervical lesions: Survival, restoration quality and costs in randomized controlled trial after 3 years

OBJECTIVE

This study compared survival, restoration quality and costs of glass hybrid (GH; EQUIA Forte Fil/EQUIA Forte Coat) and resin composite restorations (RC; OptiBond FL/Filtek Supreme XTE) of sclerotic non-carious cervical lesions.

METHODS

This is a cluster-randomized trial (ClinicalTrials.gov: NCT02631161). 88 patients (50-70 years) with 175 sNCCLs were randomized to receive GH or RC. Restorations were placed without mechanical cavity preparation and followed for a mean 36 (min/max: 31/55) months (variable follow-up due to COVID-19 lockdown). Restoration quality was re-evaluated at 1-, 18- and 36-months using FDI-criteria. Survival was assessed using multi-level Cox-regression analysis. Costs were estimated from a payer's perspective in Germany. Initial costs were determined based on micro-costing using time recordings and hourly costs, and follow-up costs based on statutory insurance fee-item-catalogues.

RESULTS

88 patients (175 restorations) were treated; 43 received GH (83 restorations), 45 RC (92 restorations). 17  GH and 19 RC showed total retention loss, 5  GH were partially lost (p = 0.396/Cox). FDI ratings were not sufficiently different for any domain except surface luster, where RC showed higher score (p < 0.001). Costs were initially lower for GH (32.57; SD 16.36 €) than RC (44.25; SD 21.40 €), while re-treatment costs were similar (GH: 9.15; SD 15.70 €; RC: 7.35; SD 14.51 €), resulting in significantly lower costs for GH (GH: 41.72; SD 25.08 €) than RC (51.60; 26.17 €) (p < 0.001/GLM).

CONCLUSIONS

While survival was not significantly different, GH was significantly less costly both initially and long-term than RC for restoring non-carious cervical lesions.

CLINICAL SIGNIFICANCE

Within this trial, survival was not significantly different between GH and RC to restore sclerotic NCCLs. As GH was significantly less costly both initially and long-term than RC, using RC was only cost-effective for payers willing to invest high additional expenses per minimal survival gains.

Three-year Clinical Performance of Two Giomer Restorative Materials in Restorations

CLINICAL RELEVANCE

The clinical performance of both conventional and flowable giomer restorative materials was particularly good in Class I restorations after three years of service.

SUMMARY

This study evaluated and compared the clinical performance of a flowable and a conventional giomer restorative material after three years. Forty-four pairs of restorations (total n=88) were placed in Class I cavities with either a flowable giomer (Beautifil Flow Plus F00; Shofu Inc, Kyoto, Japan) or a conventional giomer restorative material (Beautifil II; Shofu Inc) after the application of a dentin adhesive (FL-Bond II; Shofu Inc) and a flowable liner (Beautifil Flow Plus F03; Shofu Inc). After 3 years, 39 pairs of restorations were evaluated with the modified United States Public Health Service criteria, and digital color photographs of restorations were taken at each patient visit. The evaluation parameters were as follows: color match, marginal integrity, marginal discoloration, retention, secondary caries formation, anatomic form, surface texture, and postoperative sensitivity. Evaluations were recorded as a clinically ideal situation (Alpha), a clinically acceptable situation (Bravo), or a clinically unacceptable situation (Charlie). Data were analyzed with Fisher's exact and McNemar tests (α=0.05).None of the restorations showed retention loss, postoperative sensitivity, secondary caries, or color change. The performance of Beautifil II in terms of marginal integrity, marginal discoloration, and surface anatomic form was significantly lower at the 36-month follow-up than at baseline (p=0.007). There were no significant differences between the baseline and 36-month follow-up scores for the other criteria for Beautifil II (p>0.05). No differences were found between the baseline and the 36-month follow-up scores for any of the criteria for Beautifil Flow Plus F00 (p>0.05). No statistically significant difference in overall clinical performance was found between the 2 materials after 36 months (p>0.05).The three-year clinical performance of both restorative materials (Beautifil Flow Plus F00 and Beautifil II) was very good and not significantly different for any of the parameters evaluated.

Randomized controlled clinical trial of a highly filled flowable composite in non-carious cervical lesions: 3-year results

OBJECTIVES

This prospective, randomized, split-mouth clinical trial assessed the 3-year clinical performance of a highly filled flowable composite and a conventional paste-type composite in non-carious cervical lesions (NCCLs).

MATERIALS AND METHODS

A total of 84 NCCLs in 27 subjects were included in this split-mouth design study and randomly divided into two groups: a highly filled flowable composite Clearfil Majesty ES Flow group (ES, n = 42) and a conventional paste-type composite Majesty group (MJ, n = 42). Clearfil SE Bond was used following the manufacturer's instructions. The restorations were evaluated at baseline (BL) and 1, 2, and 3 years using FDI (World Dental Federation) criteria. Data were analysed by a paired chi-squared test for intergroup comparisons and the Friedman test for intragroup comparisons (α = 0.05).

RESULTS

Both groups had a 97.3% retention rate at the 3-year evaluation. The acceptable scores (FDI scores 1-3) for each criterion exhibited no significant difference between the MJ and ES groups at any time point (p = 1.00). The marginal adaptation performance of ES was significantly better than that of MJ at every evaluation point (p < 0.05).

CONCLUSIONS

The 3-year clinical performance of ES in NCCLs was similar to that of MJ. When the restorations were clinically acceptable, ES showed better marginal adaptation than MJ.

CLINICAL RELEVANCE

Compared with conventional paste-type composites, highly filled flowable composites showed similar clinical performance and better marginal adaptation for restoring NCCLs after 3 years.

TRIAL REGISTRATION

TRN: ChiCTR1900028484 . Date of registration: December 22, 2019, retrospectively registered.

Adhesive strategies in cervical lesions: systematic review and a network meta-analysis of randomized controlled trials

OBJECTIVES

A network meta-analysis (NMA) was performed to assess which adhesive strategy is most clinically effective in treating non-carious cervical lesions (NCCLs).

MATERIAL AND METHODS

Studies were identified by a systematic search of electronic databases including MEDLINE via PubMed, Brazilian Library in Dentistry (BBO), Cochrane Library, EMBASE, Latin American and Caribbean Health Sciences Literature database (LILACS), Scopus, and Web of Science without restrictions on publication year or language. The grey literature was also consulted. Only randomized clinical trials that compared different adhesive strategies in NCCLs in adult patients were included. The risk of bias was evaluated by using the Cochrane Collaboration tool. A random-effects Bayesian mixed treatment comparison model was used to compare adhesive strategies (3ER, 2ER, 2SE, and 1SE) at different follow-up times. The surface under cumulative ranking curve (SUCRA) was estimated for each strategy. Heterogeneity was assessed by using the Cochran Q test and I² statistics. The quality of evidence was evaluated using the GRADE approach.

RESULTS

A total of 5058 studies were identified, 66 of which met the eligibility criteria and of these 5 were judged "low" risk of bias and 57 were meta-analyzed. We did not observe significant differences in the NMA analysis for any two pairs of adhesives, except for the shortest follow-up for 2ER vs 3ER. The material 2SE ranked highest, although it differed only slightly from the other bonding strategies.

CONCLUSIONS

No bonding strategy is better than the others.

CLINICAL RELEVANCE

Adhesive efficacy cannot be characterized by its bonding strategy.

One-year evaluation of a new restorative glass ionomer cement for the restoration of non-carious cervical lesions in patients with systemic diseases: a randomized, clinical trial

OBJECTIVE

This randomized and clinical trial aimed to evaluate the performance of a new restorative Glass Ionomer Cement (GIC) for the restoration of non-carious cervical lesions (NCCLs) of patients with systemic diseases compared with a posterior resin composite after 12 months.

METHODOLOGY

134 restorations were placed at 30 patients presenting systemic diseases by a single clinician. NCCLs were allocated to two groups according to restorative system used: a conventional restorative GIC [Fuji Bulk (GC, Tokyo Japan) (FB)] and a posterior resin composite [G-ænial Posterior (GC, Tokyo Japan) (GP)] used with a universal adhesive using etch&rinse mode. All restorative procedures were conducted according to manufacturer's instructions. Restorations were scored regarding retention, marginal discoloration, marginal adaptation, secondary caries, surface texture, and post-operative sensitivity using modified United States Public Health Service (USPHS) criteria after 1 week (baseline), 6, and 12 months. Descriptive statistics were performed using chi-square tests. Cochran Q and Mc Nemar's tests were used to detect differences over time.

RESULTS

After 12 months, recall rate was 93% and the rates of cumulative retention failure for FB and GP were 4.9% and 1.6% respectively. Both groups presented similar alpha rates for marginal adaptation (FB 86.2%, GP 95.5%) and marginal discoloration (FB 93.8%, GP 97%) at 6-month recall, but FB restorations showed higher bravo scores than GP restorations for marginal adaptation and marginal discoloration after 12 months (p<0.05). Regarding surface texture, 2 FB restorations (3.1%) were scored as bravo after 6 months. All restorations were scored as alpha for secondary caries and postoperative sensitivity after 12 months.

CONCLUSION

Although the posterior resin composite demonstrated clinically higher alpha scores than the conventional GIC for marginal adaptation and discoloration, both materials successfully restored NCCLs at patients with systematic disease after a year.

CLINICAL RELEVANCE

Due to its acceptable clinical results, the tested conventional restorative GIC can be used for the restoration of NCCLs of patients with systemic diseases.

Current perspectives on dental adhesion: (1) Dentin adhesion - not there yet

The essential goal of any adhesive restoration is to achieve a tight and long-lasting adaptation of the restorative material to enamel and dentin. The key challenge for new dental adhesives is to be simultaneously effective on two dental substrates of conflicting nature. Some barriers must be overcome to accomplish this objective. While bonding to enamel by micromechanical interlocking of resin tags within the array of microporosities in acid-etched enamel can be reliably achieved and can effectively seal the restoration margins against leakage, bonding effectively and durably to organic and humid dentin is the most puzzling task in adhesive dentistry.

Much of the research and development of dental adhesives has focused on making the clinical procedure more user-friendly by reducing the number of bottles and/or steps. Although clinicians certainly prefer less complicated and more versatile adhesive materials, there is a trade-off between simplification of dental adhesives and clinical outcomes. Likewise, new materials are launched with claims of being novel and having special properties without much supporting evidence.

This review article discusses dental adhesion acknowledging pioneer work in the field, highlights the substrate as a major challenge to obtain durable adhesive restorations, as well as analyzes the three adhesion strategies and their shortcomings. It also reviews the potential of chemical/ionic dental adhesion, discusses the issue of extensively published laboratory research that does not translate to clinical relevance, and leaves a few thoughts in regard to recent research that may have implications for future adhesive materials.

Do Tooth- and Cavity-related Aspects of Noncarious Cervical Lesions Affect the Retention of Resin Composite Restorations in Adults? A Systematic Review and Meta-analysis

PURPOSE

The purpose was to perform a systematic review and meta-analysis based on the following research question: do tooth- and cavity-related aspects of noncarious cervical lesions (NCCLs) affect the retention of composite restorations?

METHODS

Randomized clinical trials (RCTs) that evaluated the retention rate of resin restorations in NCCLs were included for the identification and comparison of their characteristics. The search was conducted in PubMed and adapted for Scopus, Web of Science, Latin American and Caribbean Health Sciences Literature database (LILACS), Brazilian Library in Dentistry (BBO), Cochrane Library, and System for Information on Grey Literature in Europe (SIGLE) without restrictions until July 2018. Unpublished and ongoing trial registries were also searched. The Cochrane Collaboration tool was used for assessing risk of bias. The quality of the evidence was graded using the Grading of Recommendations: Assessment, Development and Evaluation. Using the random effects model, a meta-analysis was conducted for each aspect (arch distribution, tooth location, wear facets, dentin sclerosis, shape, size, depth, occluso-gingival distance, and margin location).

RESULTS

We retrieved 6738 articles. After removal of duplicates and nonrelevant articles, 24 RCTs remained. The anterior tooth location favored the retention rates of restoration of NCCLs (relative risk [RR], 1.08; 95% confidence interval [CI], 1.00-1.16). The presence of wear facets is a risk factor for the retention of restorations (RR, 0.91; 95% CI, 0.83-0.99). The evidence was moderate for arch distribution and low or very low for all other factors because of heterogeneity, imprecision, and inconsistency.

CONCLUSION

The tooth location and the presence of wear facets can affect the retention of composite resins in NCCLs.

Clinical Evaluation of Noncarious Cervical Lesions of Different Extensions Restored With Bulk-fill or Conventional Resin Composite: Preliminary Results of a Randomized Clinical Trial

PURPOSE

This randomized clinical trial evaluated the influence of the occlusogingival distance (OGD) of noncarious cervical lesions (NCCLs) on the clinical performance of a regular bulk-fill resin composite and a regular nanofilled resin composite.

METHODS AND MATERIALS

A total of 140 restorations were randomly placed in 77 participants by one operator. NCCLs were divided into four groups (n=35) according to OGD (1.5 mm±10% or 3 mm±10%) and resin composites (Filtek Bulk Fill Posterior [B] or Filtek Z350 XT [C]) used: 1.5 mm-B, 1.5 mm-C, 3 mm-B, and 3 mm-C. A two-step self-etch adhesive (Clearfil SE Bond) was applied following manufacturer instructions in all restorative procedures. Restorations were polished 1 week after placement. Clinical evaluation was performed at baseline (7 days), 6 months, and 1 year by two calibrated examiners, according to the modified US Public Health Service criteria evaluating fractures/retention, marginal staining, marginal adaptation, recurrence of caries, anatomic form, postoperative sensitivity, and surface texture. The Kruskal-Wallis test was used for intergroup comparison in each follow-up; the Friedman analysis of variance, followed by the least significant difference test (multiple comparisons) was used for intragroup comparison between baseline and follow-up times (α=0.05).

RESULTS

Two restorations were lost at 12 months (1 for 1.5 mm-B and 1 for 3 mm-B). The retention rates at 12 months were 100% for 1.5 mm-C, 97% for 1.5 mm-B, 100% for 3 mm-C; and 97% for 3 mm-B, with no statistical difference among the groups (p=0.570). At 12 months, a statistically significant difference was found among the follow-up times for the same group (1.5 mm-B, 1.5 mm-C, and 3 mm-B) regarding the marginal staining criterion; moreover, the 3 mm-C group showed a significant difference from 6 months. No significant difference was found for the other parameters.

CONCLUSION

Both resin composites showed acceptable clinical performance, and the OGD of NCCLs did not influence the clinical performance of resin composite restorations after 12 months.

How to Intervene in the Root Caries Process? Systematic Review and Meta-Analyses

The aim of this review as part of the preparation for a workshop organized by the European Federation of Conservative Dentistry (EFCD) in conjunction with the European Organisation for Caries Research (ORCA) was to systematically analyze available evidence of non-, micro- as well as invasive interventions for root caries lesions (RCLs). For each treatment strategy, a separate systematic review was either performed (micro-invasive and choice of restorative material) or updated (non-invasive and excavation technique) each of them following PRISMA guidelines, and if possible meta-analyses were performed. Besides the general advice to improve tooth brushing with fluoride toothpaste main findings for non-invasive interventions in RCLs, the use of dentifrices containing 5,000 ppm F- as well as professionally applied chlorhexidine varnish or silver diamine fluoride seemed to be more efficacious to arrest root caries compared to conventional fluoride toothpaste or placebo respectively. However, this conclusion is based only on a few randomized clinical trials. For micro-invasive treatments, only 2 studies focusing on sealants were available without clear conclusions. A recent review on the comparison of atraumatic restorative treatment compared with conventional treatment concluded that there is insufficient data to clearly rule out if any difference with regard to restoration longevity between both techniques exists. When restoring coventionally, composites performed better than resin-modified and glass ionomer cements. However, all materials showed rather high annual failure rates in the majority of the studies and evidence is based on a low number of prospective studies with a rather high risk of bias.

Chemical Interaction and Interface Analysis of Self-Etch Adhesives Containing 10-MDP and Methacrylamide With the Dentin in Noncarious Cervical Lesions

Objectives:

To characterize the chemical interactions and analyze the interface of adhesive systems containing 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) and N-methacryloyl glycine (methacrylamide) functional monomers with the dentin in noncarious cervical lesions (NCCLs) compared with artificial defects (ADs).

Methods and Materials:

Twenty human teeth with natural NCCLs on the buccal surface were used. Class V cavities, similar to NCCLs, were created on the lingual surface to serve as controls. Teeth were randomly allocated to two groups according to the functional monomer in the adhesive (N=10): G1, 10-MDP; and G2, methacrylamide. NCCLs and ADs were characterized by their mineral composition (MC) and degree of demineralization (DD) using micro-Raman spectroscopy, adhesive/dentin chemical interactions (CIs) were assessed with infrared photoacoustic spectroscopy, and interface morphology was evaluated with scanning electron and light microscopy. MC, CI, and DD data were submitted to Shapiro-Wilk and Student t-tests (p&lt;0.05).

Results:

Compared with ADs, dentin in NCCLs was hypermineralized (p&lt;0.05). In G1, CI, and DD in the first 2 μm, and adhesive projections in NCCLs and ADs interfaces were similar. Additionally, a thin layer of dentin collagen was observed in ADs, while it was hardly present in NCCLs. In G2, although CI could not be identified, changes in the mineral components were observed. The DD in the ADs and NCCLs were statistically similar, while SEM showed a lack of adhesion at NCCLs interface. DD and collagen exposure in the ADs and NCCLs were more pronounced than in G1.

Conclusions:

Results suggest that the G1 adhesive could be applied directly on the superficial sclerotic layer in NCCLs. In contrast, previous cavity preparation should be conducted to improve the micromechanical interaction of G2 with the dentin.

Chemical Interaction Analysis of an Adhesive Containing 10-Methacryloyloxydecyl Dihydrogen Phosphate (10-MDP) With the Dentin in Noncarious Cervical Lesions

The purpose of this study was to evaluate the chemical bonds of a self-etch 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) adhesive to natural noncarious cervical lesions (NCCLs) and compare them with those occurring in sclerotic dentin in artificially prepared defects (APDs). Four human teeth with natural NCCLs on the buccal surface were selected. Artificial defects matching the natural lesions were prepared on the lingual surface of the same teeth serving as control. Micro-Raman (MR) spectroscopy was used to quantify mineral content in natural NCCLs and in APDs. Fourier transform infrared-photoacoustic spectroscopy (FTIR-PAS) readouts were taken before and after adhesive application to analyze the protein matrix/mineral (M:M) ratio and chemical interactions between 10-MDP adhesive and dentin. The MR and FTIR-PAS spectra collected from natural NCCLs demonstrated a larger area of the band (961 cm−1, PO4) and lower M:M ratio, respectively, characterizing a hypermineralized dentin, compared with APDs. FTIR-PAS demonstrated emergence of a peak (1179 cm−1, P=O) in spectra after adhesive treatment, demonstrating a more intense chemical interaction in natural NCCLs. The results demonstrated that chemical bonding of 10-MDP adhesive to natural NCCLs is more intense, due to the hypermineralized surface, and suggest that it is unnecessary to remove the hypermineralized layer with burs, as this may decrease the chemical bonding potential of 10-MDP.

Influence of adhesive strategy on clinical parameters in cervical restorations: A systematic review and meta-analysis

OBJECTIVES

We aimed to answer the following PICO question: "Is the risk of postoperative sensitivity (POS), retention rates and marginal discoloration of composite restorations [CR] bonded with self-etch (SE) in non-carious cervical lesions (NCCLs) of adults equals to etch-and-rinse (ER) adhesives?".

METHODS

A comprehensive search was performed in May 2016 in the MEDLINE, Scopus, Web of Science, LILACS, BBO and Cochrane Library and SIGLE, abstracts of IADR, unpublished and ongoing trials registries, dissertations and theses without restrictions. Only randomized clinical trials that compared composite resin restorations placed with self-etch and etch-and-rinse in NCCLs were included. After removal of duplicates and non-eligible articles, 50 articles from 42 studies (follow-ups of the same study were merged) remained for synthesis of the risk of bias (Cochrane Risk of bias tool).

RESULTS

Thirteen studies were at "high" risk of bias, yielding 29 studies for meta-analysis. No difference on the POS after restoration placement (risk ratio [RR] 1.04; 95% CI 0.81 to 1.34) as well as in the retention rates for all follow-up periods was observed. The etch-and-rinse approach produced less marginal discoloration at 18 months to 2 years (RR 1.51; 95% CI 1.21 to 1.90) and at 4 to 5 years (RR 1.81; 95% CI 1.28 to 2.55) (p<0.0007).

CONCLUSIONS

The adhesive strategy did not influence the POS and the retention rates of composite resin in NCCLs in any of the follow-up periods; but less marginal discoloration was found in etch-and-rinse adhesives.

CLINICAL SIGNIFICANCE

Composite resin restorations placed with self-etch and etch-and-rinse adhesives produce restoration with the similar clinical service and POS, however using etch-and-rinse adhesives one can reduce marginal discoloration. PROSPERO registration number: CRD42015019533.

Adhesive systems for restoring primary teeth: a systematic review and meta-analysis of in vitro studies

AIM

To systematically review the literature for in vitro studies that evaluated the immediate or after ageing bond strength of etch-and-rinse and self-etch adhesive systems to enamel and dentin of primary teeth.

DESIGN

The search was conducted in PubMed/MEDLINE, Cochrane, SciELO, Lilacs, and Scopus databases with no publication year or language limits, following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. From 459 potentially eligible studies, 39 were selected for full-text analysis, and 5 were identified in reference lists, with 36 considered in the meta-analysis. Two reviewers independently selected the studies, extracted the data, and assessed the risk of bias. Pooling bond strength data was calculated using random effects analysis method, comparing two categories of adhesives (etch-and-rinse versus self-etch systems) when applied in different types and conditions of substrate (α  =  0.05).

RESULTS

No statistical significant difference in bond strength between both categories was observed in caries-affected dentin at immediate evaluation and in sound dentin after ageing. Etch-and-rinse adhesives, however, performed better in sound enamel and dentin substrates considering immediate bond strength. None study assessed the long-term adhesive effectiveness to sound or demineralized enamel.

CONCLUSION

Although the articles included in this meta-analysis showed high heterogeneity and high risk of bias, the in vitro literature suggests superior performance of etch-and-rinse adhesives in primary teeth in comparison with self-etch systems.

Selective enamel etching in cervical lesions for self-etch adhesives: A systematic review and meta-analysis

OBJECTIVES

To identify if selective etching of enamel (SEE) margins improves the retention rates and marginal discoloration of cervical composite restorations in non-carious cervical lesions (NCCLs) of adult patients.

SOURCE

MEDLINE, Scopus, Web of Science, LILACS, BBO Library, Cochrane Library and SIGLE were searched without restrictions, as well as IADR abstracts and gray literature via trial registries. Dissertations and theses were searched using the ProQuest Dissertations and Periódicos Capes Theses databases.

STUDY SELECTION

We included randomized clinical trials that compared the clinical effectiveness of SEE using the self-etch adhesive for direct composite resin restorations in NCCLs in the permanent dentition.

DATA

After removal of duplicates, 2689 articles were identified. Following screening of abstracts, 10 studies remained in the qualitative synthesis. Seven were considered to be at "low" risk of bias. The report of the studies varied from 1 to 5 years. Except for one-year follow-up, there was a significantly lower marginal discoloration and marginal adaptation during all follow-up periods. Significantly less loss of retention of restorations at the 3-year follow-up was observed with the selective enamel etching technique.

CONCLUSIONS

Selective enamel prior to application of self-etch adhesive systems in NCCLs might improve clinical performance of resin-composite cervical restorations, although further long-term research is required to confirm this.

CLINICAL SIGNIFICANCE

Selective enamel etching prior to application of self-etch adhesive systems in NCCLs can produce composite restorations with higher longevity.