In vitro comparison of one-step, two-step, and three-step polishing systems on the surface roughness and gloss of different resin composites.

OBJECTIVES: This laboratory study evaluated the effect of three polishing systems on the surface roughness and gloss of resin composites. MATERIALS AND METHODS: Thirty specimens (6 mm Ø × 8 mm) were fabricated from each of three resin composites: Z 350 XT (nanofill), Harmonize (nanohybrid), and Estelite Omega (supranonofill). All specimens were photopolymerized using a multi-peak LED curing unit (VALO-Standard mode), having a exitance irradiance of approximately 1000 mW/cm2 against a polyester strip (PS). 2 mm was then removed from the irradiated end (finished) using #320 abrasive paper (F). Specimens were then randomly polished (P) using a one-step (1S) (OneGloss), two-step (2S) (EVE Diacomp Twist Basic CA), or 3-step (3S) (Astropol P) system (n = 10). For PS, F, and P groups, surface roughness (Ra) was measured using a surface roughness tester, and surface gloss was measured with a glossmeter. For each specimen, the percent recovery to the PS value (%R) of surface roughness and surface gloss were calculated. Data were analyzed using two-way ANOVA, followed by Tukey's test. Surface roughness and gloss values were submitted to Pearson's correlation test (α = 0.05). All statistical testing was performed using a pre-set alpha of 0.05. RESULTS: The interaction term [resin composite × polishing system] was significant for both surface roughness (p = 0.001) and gloss (p = 0.0001). For all resin composites, the 2S and 3S systems provided a higher %R of surface roughness and gloss compared to those of the 1S system. There was a negative correlation between surface roughness and gloss, but only a few combinations showed strong correlations. CONCLUSIONS: The 2S and 3S polishing systems provided surfaces having greater smoothness and gloss compared to the 1S system. The ability to recover surface roughness and gloss was dependent on type of resin composite filler classification. CLINICAL SIGNIFICANCE: The 3S and 2S polishing systems were more effective in achieving PS values than was the 1S system for all tested resin composites. However, individual polishing systems performed differently depending on type of resin composite.

Surface smoothness of resin composites after polishing-A systematic review and network meta-analysis of in vitro studies.

A systematic review and network meta-analysis was performed to provide evidence for the best polishing protocol for different types of resin composites to minimize surface roughness. A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, EMBASE, and Cochrane Library on July 2, 2019 (updated in December, 2020). In vitro studies that included at least two systems for polishing resin composites and analyzed surface roughness were included. The risk of bias was evaluated. A random-effects Bayesian-mixed treatment comparison model was used to compare surface roughness in resin composites with the different types of polishers. Surface under the cumulative ranking curve (SUCRA) analysis was performed to rank the probability for the best polishing system. After removal of duplicates, title and abstract screening yielded 34 studies. Network meta-analysis was not possible for hybrid and microhybrid composites. SUCRA analysis showed that abrasive paper discs allowed greater surface smoothness for nanohybrid and nanofill composites to a probability of between 83% and 91.6%. Silicon carbide brush had a 78.2% probability of being the best system for microfill composites. The use of abrasive paper disc polishers showed a favorable result in nanofill and nanohybrid resin composites. Silicon carbide brush has a greater chance of promoting a smoother surface for microfill resin composites.

Efficacy of bioactive materials in preventing Streptococcus mutans-induced caries on enamel and dentine.

The study investigated the ability of bioactive materials used to restore enamel and dentine specimens to prevent caries. Enamel (n = 50) and dentine (n = 50) specimens were obtained from bovine incisors, prepared, and randomly allocated to one of five groups according to the restorative treatment: alkasite without adhesive system; alkasite with adhesive system; high viscosity glass ionomer cement; resin composite; no restoration; negative control group. Specimens were restored, exposed to a thermal cycling aging protocol, sterilized, and exposed to a cariogenic challenge induced by Streptococcus mutans and then submitted to surface and subsurface microhardness tests and polarized light microscopy to verify the caries lesion development in enamel or dentine surrounding the restorative materials. Data were analyzed using one-way ANOVA. In enamel and dentine, glass ionomer cement, alkasite without and with adhesive system presented a lower percentage surface microhardness loss than resin composite and negative control. Enamel subsurface microhardness presented no statistically significant differences between glass ionomer cement, alkasite without and with adhesive system. Glass ionomer cement also did not present statistically significant differences from resin composite and the negative control. In dentine, glass ionomer cement showed the highest subsurface microhardness values. In conclusion, bioactive restorative materials provide greater protection to enamel and dentine against surface caries development than resin composite.

Effects of lesion size on the 30-month clinical performance of restorations with bulk fill and a regular nanofilled resin composite in noncarious cervical lesions.

OBJECTIVE: The aim of this double-blind, randomized trial was to evaluate the influence of the occlusogingival distance (OGD) in noncarious cervical lesions (NCCLs) on the clinical performance of a regular bulk-fill resin composite and a regular nanofilled resin composite. MATERIALS AND METHODS: One hundred and forty NCCLs in 77 participants were randomly 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]), namely: 1.5 mm-B, 1.5 mm-C, 3 mm-B, and 3 mm-C. The restorations were bonded using a two-step self-etch adhesive (Clearfil SE Bond), applied following the manufacturer's instructions. Restorations were polished 1 week after placement. Two experienced and calibrated examiners evaluated the restorations using modified US Public Health Service criteria at baseline (7 days) and after 6, 12, 18, 24, and 30 months. Statistical analyses were carried out using Kruskal-Wallis, Friedman's repeated measures analysis of variance, and the Wilcoxon signed rank test (α = 0.05). RESULTS: After 30 months, the recall rate was 94.2%. Eight restorations were lost (3 for 1.5 mm-C, 2 for 1.5 mm-B, 1 for 3 mm-C, and 2 for 3 mm-B). All groups resulted in a significantly worse marginal discoloration and surface texture at 30 months in comparison with the baseline (1 week). No significant difference was found for the other parameters. CONCLUSION: The restorations performed with both resin composites produced clinically acceptable restorations. The OGD of NCCLs did not influence the clinical performance of restorations. CLINICAL SIGNIFICANCE: The OGD of NCCLs did not have a significant effect on the clinical performance of a regular bulk-fill and nanofilled restorations. Both materials showed a very good performance on 30-month evaluation.

Do bioactive materials show greater retention rates in restoring permanent teeth than non-bioactive materials? A systematic review and network meta-analysis of randomized controlled trials.

OBJECTIVES: To answer the following research question: does the clinical evaluation of restorations on permanent teeth with bioactive materials show greater retention rates than those with non-bioactive materials? MATERIALS AND METHODS: A search strategy was used in the following databases: MEDLINE via PubMed, Scopus, Web of Science, LILACS, BBO, Embase, The Cochrane Library, and OpenGrey. Randomized controlled trials (RCTs), with a minimum of 2-year follow-up and evaluating at least one bioactive material in permanent teeth were included. Risk of bias was detected according to the Cochrane Collaboration tool for assessing the risk of bias (RoB 2.0), and network meta-analysis was performed using a random-effects Bayesian-mixed treatment comparison model. RESULTS: Twenty-seven studies were included. The success of the restorations was assessed using modified USPHS system in 24 studies and the FDI criteria in 3 studies. Network meta-analysis revealed three networks based on restoration preparations. Resin composites were ranked with higher SUCRA values, indicating a greater likelihood of being the preferred treatment for class I, II, and III restorations. In class V, resin-modified glass ionomer cement was ranked with the highest value. CONCLUSION: Bioactive restorative materials showed similar good clinical performance in terms of retention similarly to conventional resin composites. CLINICAL SIGNIFICANCE: The findings must be interpreted with caution because many RCT on restorative materials aim to verify the equivalence of new materials over the gold standard material rather than their superiority. The present systematic review also suggests that new RCT with longer follow-up periods are necessary.

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.

Influence of different intraradicular chemical pretreatments on the bond strength of adhesive interface between dentine and fiber post cements: A systematic review and network meta-analysis.

Systematic review and network meta-analyses were performed to answer the question: Do intraradicular chemical pretreatments affect the bond strength of the adhesive interface between dentine and fiber post cements? A literature search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, and Cochrane Library in October 2018 (updated September 2021). In vitro studies that compared the bond strength assessed by push-out tests following at least two dentine chemical treatments prior to fiber post cementation were included. Risk of bias was evaluated. A random-effects Bayesian-mixed treatment comparison model was used to compare push-out bond strength of different chemical pretreatments. SUCRA (surface area under the cumulative ranking) analysis was performed to rank the pretreatments. After removing duplicates and screening titles and abstracts, 61 studies remained. SUCRA analysis showed that the best bond strength values for self-etch, etch-and-rinse, and self-adhesive cements were ethyl acetate (SUCRA: 99.8%), low concentration NaOCl (SUCRA: 83.4%), and grape seed extract (SUCRA: 97.6%), respectively. According to the SUCRA rankings, ethanol was in a good position for all adhesive strategies (SUCRA: 78.6%). The use of chemical pretreatments in intraradicular dentine of endodontically treated teeth depends on the adhesive and cementation strategy. The pretreatment generally associated with the highest bond strength was ethanol.

Fatigue behavior and stress distribution of molars restored with MOD inlays with and without deep margin elevation.

OBJECTIVES: This study evaluated the effect of deep margin elevation (DME) and restorative materials (leucite-reinforced glass-ceramics [C] vs. indirect resin composite [R]) on the fatigue behavior and stress distribution of maxillary molars with 2-mm deep proximal margins restored with MOD inlay. METHODS: Fifty-two extracted human third molars were randomly assigned into four groups (n = 13): C; DME + C; R; and DME + R. Inlays were fabricated in CAD-CAM and bonded to all teeth. The fatigue behavior was assessed with the stepwise stress test (10,000 cycles/step; step = 50 N; 20 Hz; initial load = 200 N). Fatigue failure loads and the number of cycles were analyzed with 2-way ANOVA and Tukey's test (p < 0.05) and Kaplan-Meier survival plots. The stress distribution was assessed with finite element analysis. The models were considered isotropic, linear, and homogeneous, and presented bonded contacts. A tripod axial load (400 N) was applied to the occlusal surface. The stress distribution was analyzed with the maximum principal stress criterion. RESULTS: For fatigue, there was no difference for DME factor (p > 0.05). For the material factor, the load and number of cycles for failure were statistically higher in the R groups (p < 0.05). The finite element analysis showed that resin composite inlays concentrated more stress in the tooth structure, while ceramic inlays concentrated more stress in the restoration. Non-reparable failures were more frequent in the resin composite inlays groups. CONCLUSIONS: DME was not negative for fatigue and biomechanical behaviors. Resin composite inlays were more resistant to the fatigue test, although the failure mode was more aggressive. CLINICAL SIGNIFICANCE: DME does not impair mechanical behavior. Resin composite inlays failed at higher loads but with a more aggressive failure mode.

Effect of intraradicular fiber post on the fracture resistance of endodontically treated and restored anterior teeth: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: A fiber post is indicated when there is a significant loss of tooth structure and additional support for the restoration is needed. However, whether the use of a glass fiber post affects the fracture susceptibility of the restored anterior teeth is unknown. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the fracture resistance of endodontically treated and restored anterior teeth and to answer the research question, "Does the use of a fiber post influence the fracture resistance of endodontically treated and restored anterior teeth compared with alternative restorative treatments?" MATERIAL AND METHODS: A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and Embase databases without date and/or language restrictions (updated in July, 2020). In vitro studies comparing the fracture strength of endodontically treated and restored anterior teeth with and without fiber posts were included. The risk of bias was evaluated by using the previous meta-analyses of in vitro studies. The results were presented as standardized mean difference with a 95% confidence interval. Statistical heterogeneity of treatment effects between studies was assessed using the Cochran Q test and the I2 inconsistency test, and values greater than 50% were considered indicative of substantial heterogeneity. RESULTS: After the removal of duplicates and title and abstract screening, 31 studies remained. Seventeen were considered low risk of bias, 10 were medium risk of bias, and 4 were high risk of bias. Meta-analysis comparing control and experimental groups favored the use of a fiber post in endodontically treated teeth with some types of restoration to improve fracture resistance (standardized mean difference= 0.5 [0.08; 0.92]); a glass fiber post was also favored (standardized mean difference=0.92 [0.43; 1.42]); for veneer preparations and teeth with cervical cavities, a fiber post increases the fracture strength (standardized mean difference= 0.74 [0.01; 1.47]; 1.18 [0.35; 2.02], respectively). CONCLUSIONS: The use of glass fiber posts increases the fracture resistance of endodontically treated and restored teeth.

Bacterial levels and amount of endotoxins in carious dentin within reversible pulpitis scenarios.

OBJECTIVES: the objective of the present exploratory study was to determine bacterial diversity and endotoxin levels in deep carious lesions of teeth presenting symptoms of reversible pulpitis. MATERIALS AND METHODS: Twenty patients with deep carious lesions, reporting clinical symptomatology compatible with reversible pulpitis (n = 10) or not reporting clinical symptomatology (n = 10), were selected. Carious dentin samples were obtained with the aid of sterile and pyrogen-free spoon excavators and harvested in two steps: before and after infected dentin removal. Samples were collected for checkerboard and for kinetic chromogenic LAL assay for determination of microbial profile and quantitation of endotoxin, respectively. Data were analyzed by Mann Whitney for bacteria and two-way ANOVA for endotoxins (5%). RESULTS: No difference on the studied bacteria was detected between the superficial and deep dentin layers. Symptomatic teeth showed greater presence of Lactobacillus species, Capnocytophaga sputigena, and Leptotrichia buccalis. For the endotoxins, symptomatic teeth resulted in greater quantity of endotoxins (p = 0.047), being 4.13 log10 EU/mL/µg dentin and 3.45 log10 EU/mL/µg dentin, for symptomatic and asymptomatic teeth, respectively. Dentin collected in different areas presented similar number of endotoxins (p = 0.139). CONCLUSION: The amount of the studied bacteria does not seem to be related to reported symptomatology of deep carious lesions, while endotoxins quantity is greater in symptomatic scenarios, regardless of the harvesting area. CLINICAL RELEVANCE: The understanding of bacterial amount in reversible pulpitis is important to establish a clinical protocol of treatment.

Influence of glass fiber posts on the fracture susceptibility of endodontically treated maxillary anterior teeth with direct veneers: Preliminary results of a randomized clinical trial.

OBJECTIVE: The purpose of this randomized clinical trial was to evaluate the influence of glass fiber posts on fracture susceptibility of endodontically treated maxillary anterior teeth with direct veneers. MATERIALS AND METHODS: Fifty participants had 1 maxillary anterior tooth restored with a direct veneer. They were divided into 2 groups (n = 25) according to the use of intraradicular glass fiber posts. Clinical evaluation was performed at baseline, 6 and 12 months. The treatment success was determined by the absence of tooth fracture. If there was fracture, it was classified according to its extent. Fischer exact test was performed to analyze the criteria among the groups at each evaluation time. Friedman repeated analysis of variance assessed the difference in the performance of each group at three recall times (α = 0.5). RESULTS: For control group, at the 6-month follow-up, one tooth had suffered a catastrophic failure, which resulted in tooth extraction. Fisher statistical analysis showed no significant difference between the cumulative success rate of the groups for the 6 (P > .999) and the 12-month (P > .999) period. Friedman test showed no significant difference among the periods of evaluation (P > .999). CONCLUSIONS: Both groups had a similar success rate for maxillary anterior endodontically treated teeth with direct veneers after 12 months. CLINICAL IMPLICATIONS: Glass fiber post use does not influence the fracture susceptibility of maxillary anterior endodontically treated teeth with direct veneers in the short term.

Impact of simulated toothbrushing on surface properties of chairside CAD-CAM materials: An in vitro study.

STATEMENT OF PROBLEM: Chairside computer-aided design and computer-aided manufacturing (CAD-CAM) materials that do not require any firing steps are a promising option to expedite restoration production; however, little information is available to determine the most suitable material for each clinical situation. PURPOSE: The purpose of this in vitro study was to evaluate the effect of simulated toothbrushing on surface gloss, roughness, and wear of chairside CAD-CAM materials. MATERIAL AND METHODS: Disk-shaped specimens (n=15) were prepared of the following materials: ENA-VITA Enamic; LAV-Lava Ultimate; EMP-IPS Empress CAD; CER-Cerasmart; GRA-Grandio blocs. Gloss (Gloss Unit-GU) and surface roughness (Ra-µm) were evaluated before and after simulated toothbrushing (100 000 strokes). Wear (µm) was assessed by contact profilometry. Additional analyses of microhardness by scanning electron microscopy were also performed. Data were analyzed with 2-way repeated measures ANOVA test for roughness and gloss, and 1-way ANOVA for wear (α=.05). To estimate the correlation between Ra and GU, the Pearson correlation was calculated. RESULTS: Before brushing, CER showed the lowest Ra (P<.001), and GRA the lowest GU values. After brushing, the feldspathic ceramic-based materials (ENA and EMP) presented the highest gloss, whereas the ceramic group (EMP) showed the lowest Ra. Before and after brushing, GRA showed the lowest GU values. Higher wear values were found for the composite resin groups (CER>GRA), with the exception of LAVA, which was similar to ENA, and EMP showing improved wear resistance. A strong negative correlation (-0.925) between GU and Ra values was detected (P<.001). CONCLUSIONS: The materials containing a glass phase (ENA and EMP) presented higher wear resistance, higher gloss, and lower roughness after brushing than the other materials tested. The correlation test showed that the higher the surface roughness, the lower the gloss.

Conservative approach to treating severe tetracycline staining: a 12-month follow-up.

Severe tetracycline staining may affect the esthetics of teeth and the self-esteem of patients. This case report describes minimally invasive treatment with dental bleaching and direct restorations to improve the esthetics of tetracycline-stained teeth in a 44-year-old woman. All of the patient's teeth were affected by grayish brown staining, and the maxillary central incisors demonstrated incisal wear. The buccal angulation of the anterior teeth and the patient's Class II skeletal profile hindered the use of direct or indirect veneer restorations. The proposed treatment was home bleaching with 10% carbamide peroxide applied in a soft vinyl tray, which was worn overnight for the first 3 months and 2 hours daily for the next 3 months (total treatment time of 6 months). Afterward, a single session of in-office bleaching with 37% hydrogen peroxide was performed over resistant bands of staining observed at the cervical thirds of the teeth. Fourteen days after the in-office bleaching treatment, composite resin restorations were placed at the incisal areas of the maxillary central incisors and the cervical areas of the central incisors, lateral incisors, and canines to treat the incisal wear and mask the remaining dental discoloration. In some cases, minimally invasive treatment with tooth bleaching might be indicated for the esthetic treatment of teeth severely stained by tetracycline, although this approach presents limitations. In the present case, the patient was satisfied with her smile after the treatment protocol was completed, and the results remained stable after 12 months. The patient reported an improved quality of life after treatment.

A 2-year clinical evaluation of direct and semi-direct resin composite restorations in non-carious cervical lesions: a randomized clinical study.

OBJECTIVES: The purpose of this study was to evaluate the 2-year success of resin composite restorations in non-carious cervical lesions (NCCLs) using the direct or semi-direct techniques. MATERIALS AND METHODS: Thirty volunteers presenting with at least two NCCLs were included. Each participant received one restoration using the direct technique and the other using the semi-direct technique, totaling 60 restorations. Time for completing the treatment was computed. Assessments at baseline, 7 days, and 6, 12, and 24 months were performed using the modified United States Public Health Service criteria. Descriptive analysis was reported as a percentage of successful treatments. For inferential analysis, the Student t test was used to evaluate the differences between extension, depth, and time. The chi-square/Fisher tests were used to compare treatment success after each period (α = 0.05). The results were evaluated by using the Kaplan-Meier survival analysis. RESULTS: Differences were detected regarding mean ± standard deviation time, in which direct and semi-direct procedures were accomplished in 21.8 (± 14.5) and 35.3 (± 19.9) min, respectively. Of the 60 restorations placed, 7 failed in the direct group while 8 failed in the semi-direct group up to 2 years. No differences were detected between restorative protocols. The cumulative survival was 88.5% and 88.4% for the direct technique and semi-direct techniques after 24 months, respectively. CONCLUSION: The tested restorative protocols present similar results for NCCLs within the studied periods. CLINICAL RELEVANCE: The semi-direct technique exhibited clinical performance similar to direct technique for NCCL, demonstrating an alternative for restorations of these lesions.

Reshaping a retained deciduous canine with a semidirect composite resin veneer: A clinical report.

The presence of a retained primary canine in an adult, although not frequent, affects esthetics. Choosing the optimal restorative treatment is a challenge. The present clinical report describes a treatment for tooth reshaping with a semidirect composite resin technique, achieving an excellent esthetic result. The treatment was successful at the 18-month follow-up.

Can different etching protocols change the properties of a hybrid ceramic?

The aim of this study was to evaluate the effects of different concentrations of hydrofluoric acid (HF) and etching times on the flexural strength, roughness, wettability, and type of failure of a hybrid ceramic (VITA ENAMIC). Blocks of the ceramic material were made according to the norms of International Organization for Standardization standard 6872:2015 and randomly divided into 7 groups (n = 13): control (no treatment); surface etching with 5% HF for 30 (HF5-30), 60 (HF5-60), or 90 (HF5-90) seconds; and surface etching with 10% HF for 30 (HF10-30), 60 (HF10-60), or 90 (HF10-90) seconds. The adhesive surface of 10 specimens in each group was cemented with dual-curing resin cement. The specimens were submitted to biaxial flexural tests and fractographic analysis. Surface analyses were carried out using 3 noncemented specimens from each group. The surface roughness was evaluated through optical profilometry and the surface wettability through goniometry (contact angle). The values obtained were analyzed by a Dunnett test followed by 2-way analysis of variance and Tukey test (α = 5%). The flexural test results indicated a statistically significant reduction in the resistance of the ceramic when conditioned with 10% acid (P < 0.01). Etching with HF, at any concentration used for any applied time, significantly modified the ceramic roughness of the experimental groups (P < 0.01). The wettability was also significantly altered in the HF5-90 group and in all HF10 groups (P < 0.01). The higher the concentration of the acid, the lower the wettability of the ceramic (P < 0.01). Based on these results, a 5% HF concentration is best indicated for the surface treatment of VITA ENAMIC.

Auxiliary UV light devices for removal of fluorescent resin residues after bracket debonding.

OBJECTIVE: The purpose of this clinical report was to describe the detection of fluorescent resin residue after orthodontic bracket debonding with two UV light devices and analyze the surface morphology of enamel after 1 year. CLINICAL CONSIDERATIONS: A 22-year-old woman had orthodontic brackets removed by a previous dentist; however, resin residue was left on the enamel of the maxillary teeth. After confirming the fluorescent property of the resin, different protocols were used for each half of the maxillary arch. The first method, a black light lens was attached to a light-curing device to detect resin fluorescence, followed by polishing with silicone rubber tips. The second method used a light emitting diode light system attached to and activated by a high-speed handpiece, followed by polishing with discs. Both methods were completed with diamond polishing paste applied with felt discs. Polyvinyl siloxane impressions were made initially, after residue removal, after finishing and after polishing for morphologic analysis. The results were evaluated with photographs and the scanning electron microscope images made of resin casts from the impressions. A follow-up was made after 1 year. CONCLUSIONS: Both methods yielded a satisfactory clinical outcome, with a smooth surface, acceptable surface gloss and minimal tooth wear. The use of a UV device that excites fluorescence is recommended for the controlled removal of resin residue on enamel. CLINICAL SIGNIFICANCE: The controlled removal of resin residue from enamel after orthodontic treatment is challenging but can be improved with auxiliary methods for detecting resin residues. This clinical report describes two types of devices that excite fluorescent resins in a more rapid and precise technique to guide the practitioner in the controlled removal of residual resin on teeth.

Photodynamic inactivation of planktonic cultures and Streptococcus mutans biofilms for prevention of white spot lesions during orthodontic treatment: An in vitro investigation.

INTRODUCTION: This study evaluated the efficacy of photodynamic inactivation (PDI) with hematoporphyrin IX (H) and modified hematoporphyrin IX (MH) at 10 µmol/L, using a blue light-emitting diode (LED), fluence of 75 J/cm,2 over planktonic cultures and biofilm of Streptococcus mutans (UA 159). METHODS: Suspensions containing 107 cells/mL were tested under different experimental conditions: a) H and LED (H+L+), b) MH and LED (MH+L+), c) only LED (P-L+), d) only H (H+L-), e) only MH (MH+L-), and f) control group, no LED or photosensitizer treatment (P-L-). The study also evaluated the effect of PDI on S mutans biofilm on metallic or ceramic brackets bonded on specimens of human teeth. The strains were seeded onto Mitis salivarius-bacitracin-sacarose agar to determine the number of colony-forming units. RESULTS: H and MH under LED irradiation were effective on planktonic cultures (P <0.0001). H and MH (H+L+ and MH+L+) caused a reduction of 3.80 and 6.78 log10 CFU/mL. PDI with the use of H or MH and LED exerted a strong antimicrobial effect over S mutans showing 54% and 100% reduction, respectively. PDI on S mutans biofilm on metallic and ceramic brackets with the use of H was not effective (P = 0.0162, P = 0.1669), however, MH caused a significant reduction of 44% and 53% of the cell count on metallic and ceramic brackets, respectively (P = 0.0020, P = 0.004). CONCLUSIONS: In vitro planktonic cultures with the use of H or MH and LED exerted significant antimicrobial activity. No effect was observed on S mutans biofilm on either bracket type with the use of H, MH showed better results, suggesting a promising use against dental caries and white spot lesions.

Treatment of single maxillary gingival recession associated with non-carious cervical lesion: Randomized clinical trial comparing connective tissue graft alone to graft plus partial restoration.

BACKGROUND: Gingival recession (GR) is frequently associated with non-carious cervical lesion (NCCL) forming a combined defect (CD). The aim of this study was to evaluate a new multidisciplinary protocol for CDs. METHODS: Forty patients presenting 40 Miller's Class I or II GR defects associated with B+ tooth cervical defect were randomly allocated to one of the following treatments: test group (n = 20), partial restoration (PR) of the NCCL, in which the apical border of the restoration was placed 1 mm beyond the cement-enamel junction estimation, and connective tissue graft (CTG + PR) and Control Group (n = 20), odontoplasty of the NCCL and connective tissue graft (CTG). Clinical, aesthetic and patient-centred outcomes were evaluated. RESULTS: After 12 months, CD coverage rates were 75.3% (2.5 ± 1.0 mm) for CTG + PR and 74.6% (2.4 ± 1.1 mm) for CTG (p > 0.05). The estimated complete root coverage was 60% (n = 12) for CTG + PR and 70% (n = 14) for CTG. CTG + PR resulted in significantly better dentin hypersensitivity (DH) reduction (p = 0.034). Both groups resulted in aesthetic improvements; however, the CTG + PR group showed better gingival contour results. CONCLUSIONS: CTG and CTG + PR were effective to treat CD. Use of PR resulted in better gingival margin contour and DH reduction, without effect on CD coverage by CTG. (NCT02817763).

Evaluation of the bond strength and characteristics of zirconia after different surface treatments.

STATEMENT OF PROBLEM: Nonthermal plasma treatment could increase the bond strength of resin cements to zirconia, but studies are lacking. PURPOSE: The purpose of this in vitro study was to evaluate zirconia bond strength, surface roughness, and contact angle and to measure the infrared spectrum after different surface treatments. MATERIAL AND METHODS: Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP; n=9) blocks were sectioned into 36 slices (12×11×3 mm) and divided (n=4) into surface treatment groups as follows: 2 control groups, consisting of airborne-particle abrasion plus primer (APP) and 10% hydrofluoric acid etching plus primer (HFP), and 3 experimental groups consisting of a nonthermal plasma (NP) application; a nonthermal plasma plus primer application (NPP); and a 10% hydrofluoric acid etching plus nonthermal plasma plus primer (HFNPP) application. Each zirconia disk was cemented to a prepolymerized resin block. After cementation, the specimens were sectioned for microtensile strength testing and for surface roughness analysis and contact angle analysis. Results were submitted to analysis of variance and Tukey tests (α=.05). RESULTS: Results showed no statistically significant differences between the APP and HFNPP groups, but these 2 groups showed statistically better bonding than those of HFP, NP, and NPP. CONCLUSIONS: Airborne-particle abrasion resulted in a significant increase in surface roughness compared with the other groups. After nonthermal plasma treatment, the contact angle of the zirconia surface decreased within 48 hours. Nonthermal plasma application for surface treatment of zirconia showed no significant difference in bond strength when compared with airborne-particle abrasion.