Treatment of Molar-incisor Hypomineralization: A Case Report of 11-year Clinical Follow-up.

The purpose of this case report was to describe an 11-year follow-up of a patient presenting with molar-incisor hypomineralization (MIH) having yellowish and porous permanent incisors and molars. Clinical examination revealed demarcated brown opacities on one upper and one lower central incisor and three first permanent molars. Initially, treatment involved oral hygiene and periodic fluoride varnish application. Subsequently, the occlusal surfaces of the affected molars were restored or sealed with glass ionomer cement. At-home dental bleaching was also performed. Areas of unsatisfactory esthetics on the incisors were replaced by composite resins. This report discussed the patient's needs and expectations, the difficulties of prolonged treatment for patients with MIH, and the restorative protocol involving at-home dental bleaching and composite resins.

Does the Bleaching Gel Application Site Interfere With the Whitening Result? A Randomized Clinical Trial.

This study aimed to evaluate the effect of the bleaching gel application site on chromatic changes and postoperative sensitivity in teeth. Thirty patients were selected and allocated to three groups (n=10 per group), according to the location of the gel: GI, cervical application; GII, incisal application; and GIII, total facial. The amount and time of application of the 35% hydrogen peroxide (H2O2) gel were standardized. Color changes were analyzed by ΔE and Wid (bleaching index), using the values obtained in the readings conducted on a digital spectrophotometer in the cervical (CRs) and incisal regions (IRs) of the teeth. Spontaneous sensitivity was assessed using the questionnaire, and the stimulated sensitivity caused by the thermosensory analysis (TSA). The analysis occurred in five stages: baseline, after the first, second, and third whitening sessions (S), and 14 days after the end of the whitening, using the linear regression statistical model with mixed effects and post-test by orthogonal contrasts (p<0.05). Although the IR was momentarily favored, at the end of the treatment, the restriction of the application site provided results similar to those obtained when the gel was applied over the entire facial surface. Regarding sensitivity, only the GI showed spontaneous sensitivity. In the TSA, GIII had less influence on the threshold of the thermal sensation. It was concluded that the chromatic alteration does not depend on the gel application site. Spontaneous sensitivity is greater when the gel is concentrated in the cervical region (CR), and the teeth remain sensitized by thermal stimuli even after 14 days.

Three-year Randomized Prospective Clinical Trial of Class II Restorations Using Flowable Bulk-fill Resin Composites.

OBJECTIVES: This randomized, prospective, and split-mouth study aimed to evaluate flowable bulk-fill resin composites in class II restorations and to compare with a conventional layering technique after a 3-year follow-up. METHODS AND MATERIALS: Fifty-three subjects received three class II restorations according to the restorative systems: conventional microhybrid resin composite (PA, Peak Universal + Amelogen Plus, Ultradent), flowable bulk-fill and nanoparticulate resin composites (ABF, Adper Single Bond 2 + Filtek Bulk Fill Flow + Filtek Z350XT, 3M Oral Care), and flowable bulk-fill and microhybrid resin composites (XST, XP Bond + SDR + TPH3, Dentsply). The clinical performance and interproximal contacts were evaluated. Statistical analyses were performed using the equality test of two proportions, Logistic regression analysis, Friedman, Wilcoxon, Kruskal-Wallis, and Mann-Whitney tests (a=0.05). RESULTS: Forty-seven patients were evaluated at 3 years. XST bulk-fill restorative system presented higher marginal discoloration than PA, and the opposite occurred for surface staining. All restorative systems resulted in decreased interproximal contacts, occurring early for XST. CONCLUSIONS: Although the restorative system using incremental technique presented better performance for marginal discoloration, one of the restorative systems that used flowable bulk-fill resin composite (XST) showed the lowest surface staining. All restorative systems had decreased proximal contact over time.

Wear, roughness and microhardness analyses of single increment restorative materials submitted to different challenges in vitro.

PURPOSE: To evaluate the microhardness, roughness, profilometry and cross-sectional hardness of single increment materials submitted to different challenges. METHODS: Thirty-six disks of each material, Filtek Supreme XTE (FT), Filtek One Bulk Fill (BK), Ketac Molar Easy Mix (KT) and Equia Forte + Coat (EQ) were immersed in saliva, pH cycling and Coke for 15 days. Half of each surface was used as its own control. Superficial microhardness, roughness, perfilometry analysis were performed. All samples were sectioned, embedded in acrylic resins, polished and cross-sectional hardness were made. Data were analyzed by ANOVA and Tukey's test (p < 0.05). RESULTS: The KT presented superficial microhardness superior than EQ. However, in depth, EQ showed superior values. FT, KT suffered the effects of challenges on microhardness values. The highest roughness and wear values were found for KT. RC do not suffer wear. All materials suffered the effects of Coke and pH challenges in depths 10 µm and 60 µm. CONCLUSION: The single increment restorative material that suffered less action on its surface was the bulk-fill resin. The coat present in the hybrid ionomer was able to resist to the immersion actions. In addition, Coke was the most aggressive challenge.

In vivo acid etching effect on bacteria within caries-affected dentin.

Acid etching procedures may disrupt residual bacteria and contribute to the success of incomplete caries removal followed by adhesive restoration. This study evaluated the in vivo effect of acid etching on cariogenic bacterial activity within affected dentin after minimally invasive treatment of caries lesions. Twenty-eight carious permanent teeth received standardized selective caries removal and random acid etch treatment (E) or not (NE) prior to adhesive restoration. Baseline and 3-month dentin biopsies were collected. The number of bacteria and activity of total bacterial cells and Streptococcus mutans were determined by quantitative PCR and RT-PCR. No statistically significant differences were observed in total bacterial number and activity between E and NE treatments (p > 0.3008). For NE, however, the residual S. mutans bacterial cells were reduced (p = 0.0027), while the activity per cell was significantly increased (p = 0.0010) after reentry at 3 months after restoration. This effect was not observed in group E. Although no significant differences were found between groups, this study suggests that acid etching of affected dentin prior to adhesive restoration may directly or indirectly have an inhibitive effect on the activity of residual cariogenic bacteria. Further research is required to investigate this potential effect.

Perceptibility and Acceptability of Surface Gloss Variations in Dentistry.

OBJECTIVE: To assess the visual perception of observers regarding perceptibility and acceptability of surface gloss variations of resin composites and to determine the limit of perceptibility and acceptability of gloss variations. METHODS: Eight resin composite specimens and one human tooth specimen were fabricated. The resin specimens were polished to reach a surface gloss, in gloss units (GUs), of 10 GU, 20 GU, 30 GU, 40 GU, 50 GU, 60 GU, 70 GU, and 80 GU, and the human tooth specimen had a surface gloss of 80 GU. Sixty observers were selected to compare the surface gloss of the specimens in a light booth. For the perceptibility assessment, specimens were randomly displayed two at a time. Each observer performed a total of 144 observations. Observers answered two specific questions for determining the level and limit of perceptibility of gloss variations. The acceptability limit of gloss was determined by comparing the resin specimens with the tooth specimen. The observations were performed with dental practice scenarios (illuminant conditions, visualization field, and observers' education). Data were submitted to a nonlinear probit model and nonlinear regression estimation probit (5%). RESULTS: Differences in perceptibility and acceptability were observed for surface gloss variations (ΔGU) (p<0.001). Perceptibility increased with ΔGU (10<20<30<40<50=60=70), while acceptability decreased with ΔGU (0=10>20>30>40>50>60=70). Acceptability and perceptibility limits were 6.4 GU and 35.7 GU, respectively. CONCLUSIONS: Perceptibility and acceptability of surface gloss are influenced by gloss variations. A variation of 6.4 GU was required for 50% of observers to notice gloss variations. Concerning acceptability, observers required a variation of 35.7 GU to consider differences in gloss not acceptable.

Randomized Prospective Clinical Trial of Class II Restorations Using Low-shrinkage Flowable Resin Composite.

PURPOSE: The aim of this prospective, randomized, split-mouth clinical trial was to evaluate postoperative sensitivity, clinical performance, and interproximal contacts after using different restorative systems. METHODS AND MATERIALS: Fifty-three subjects each received three class II restorations according to the restorative systems: conventional resin composite (PA: Peak Universal+Amelogen Plus, Ultradent), low-shrinkage flowable and nanoparticulate resin composites (ABF: Adper Single Bond 2+Filtek Bulk Fill Flow+Filtek Z350XT, 3M ESPE), and low-shrinkage flowable and microhybrid resin composites (XST: XP Bond+SDR+TPH3, Dentsply). Postoperative sensitivity was assessed at 24 hours, seven days, 90 days, and six months. The clinical performance and interproximal contacts were evaluated at baseline, six months, and one year. Friedman, Wilcoxon, Kruskal-Wallis, and Mann-Whitney tests were used to evaluate postoperative sensitivity and interproximal contacts. The equality test of two proportions and logistic regression analysis were used to assess the clinical performance. RESULTS: No statistically significant differences were observed among groups for postoperative sensitivity. The highest spontaneous sensitivity was reported at 24 hours. ABF was the only group that did not present a reduction in cold sensitivity. Color, marginal discoloration, and superficial staining showed differences among the groups. XST did not show superficial staining after one year. No differences were observed among groups in relation to interproximal contacts. XST resulted in the loss of interproximal contact after one year. CONCLUSIONS: Different types of restorative systems do not influence postoperative sensitivity; however, ABF maintained cold sensitivity over time. Marginal discoloration occurred for all groups but occurred earliest for PA. XST presented a reduction of interproximal contact after one year of evaluation.

A New Approach for Dental Bleaching Using Violet Light With or Without the Use of Whitening Gel: Study of Bleaching Effectiveness.

The objective of this study was to evaluate the effectiveness of violet light-emitting diodes (LEDs) in dental bleaching treatment when used in conjunction with bleaching gels containing different concentrations of hydrogen peroxide (HP). Here, 90 bovine teeth (n=15) were randomly assigned to the following groups: GI, placebo without light; GII, 35% HP without light; GIII, 17.5% HP without light; GIV, placebo with violet LED; GV, 35% HP with violet LED; and GVI, 17.5% HP with violet LEDs. Three bleaching sessions of 45 minutes were conducted; 21 cycles involving one minute of irradiation by violet LEDs with 30-second intervals were performed during each session of bleaching (GIV, GV, and GVI). Color changes (ΔE, ΔL, Δa, and Δb) were analyzed using a visible ultraviolet light spectrophotometer 7 days after each bleaching session. The mean ΔE, ΔL, Δa, and Δb values were compared between groups by analysis of variance and Tukey tests, with a significance level of 5%. The groups treated with 35% HP had higher ΔE and ΔL and lower Δb values, regardless of whether violet light was used. The group that received only violet LED differed from the control group in terms of ΔE, and the group treated with 17.5% HP and violet LED presented higher ΔE values than the group treated with 17.5% HP only. Thus, violet light did not influence bleaching efficacy when using 35% HP, but when used in conjunction with 17.5% HP, it increased the bleaching efficacy. Moreover, use of the violet LED only also prompted a bleaching effect, although it was less marked.

Influence of protease inhibitors on the degradation of sound, sclerotic and caries-affected demineralized dentin.

The aim of this study was to evaluate influence of protease inhibitors on degradation of sound, sclerotic and caries-affected dentin. Thirty-nine molars were used, thirteen for each dentin condition. Three slices were obtained from each tooth, each one immersed in the following different solutions for 1 h: 1) artificial saliva; 2) 2% chlorhexidine; 3) 0.5% epigallocatechin-gallate (EGCG). After immersion, samples were subjected to enzymatic degradation challenge (collagenase from Clostridium histolyticum). Nanohardness (HIT) and elastic modulus (Er) were measured before and after enzymatic challenge, as well as the ultimate tensile strength (UTS). Results of UTS, HIT and Er tests were submitted to repeated measurements ANOVA and Tukey post-test (α = 0.05). Higher values of UTS were found for sound dentin in control (40.30 ±â€¯21.38 MPa) and 0.5% EGCG (30.05 ±â€¯19.67 MPa) groups. Before degradation, higher values of HIT (0.237 ±â€¯0.062 GPa) and Er (5.58 ±â€¯1.75 GPa) were found for 0.5% EGCG group in caries-affected dentin. After degradation, 2% chlorhexidine group had higher values of HIT and Er for sound (0.134 ±â€¯0.020 GPa and 3.57 ±â€¯0.40 GPa) and sclerotic (0.201 ±â€¯0.048 GPa and 4.30 ±â€¯0.56 GPa) dentin. The 2% chlorhexidine showed best effect increasing HIT and Er, mainly for sclerotic dentin, before/after enzymatic degradation. The 0.5% EGCG showed better effect on HIT and Er in caries-affected dentin, before enzymatic degradation.

Conservative Approach for Treatment of Maxillary Lateral Incisor Agenesis With the Deciduous Tooth Retained: 18-Month Follow-Up.

This case describes a female patient with agenesis of the maxillary right lateral incisor, with her permanent canine in its position and the deciduous canine retained. Additionally, she presented with a maxillary left peg lateral incisor. To solve her functional and esthetic complaints, a multidisciplinary approach involving perio-restorative procedures was proposed. Periodontal surgeries were performed to align the gingival contour, and the restorative approach utilized ceramic veneers. At the 18-month clinical and radiographic follow-up, the treatment outcome was stable, with maintenance of the clinical results achieved and without any sign of deciduous tooth resorption.

Microhardness and Roughness of Infiltrated White Spot Lesions Submitted to Different Challenges.

A white spot lesion is the first clinical sign of a caries lesion and represents mineral loss from the enamel subsurface. The purpose of this study was to evaluate the microhardness and surface roughness of white spot lesions after application of a resin infiltrant and subjection to different challenges. Caries-like lesions were induced in bovine enamel discs (n=50), and the specimens were randomly divided into five study groups (n=10): demineralized enamel (negative control, G1), infiltrated enamel (G2), infiltrated enamel submitted to brushing (G3), infiltrated enamel submitted to pH cycling (G4), and infiltrated enamel submitted to artificial aging (G5). Half of each enamel surface was used as its own positive control. Roughness data were analyzed using the Kruskal-Wallis test followed by the Dunn test. Results from microhardness were analyzed by two-way analysis of variance, followed by the Tukey test for multiple comparisons. The level of significance was set at 5%. Microhardness and roughness values obtained from the test side of the specimens were significantly lower compared with the sound enamel for all groups. Microhardness values obtained for G2, G3, and G5 were not significantly different. Values found for G1 were significantly lower compared with those for G2, G3, and G5. The lowest microhardness values were observed for G4, which was significantly different from the other groups. Surface roughness was not significantly different between G2 and G3. The resin infiltrant presented superiority over the unprotected white spot lesions, as they were more resistant to mechanical and aging challenges. However, resin infiltration was not able to reestablish the properties of sound enamel and was not resistant to a new cariogenic challenge.

An In Situ Study of the Influence of Staining Beverages on Color Alteration of Bleached Teeth.

The aim of this study was to evaluate overall color change in bovine tooth fragments submitted to dental bleaching treatment performed simultaneously with the ingestion of beverages containing dyes. For this purpose, tooth fragments assembled into intraoral devices were submitted to at-home dental bleaching using 10% carbamide peroxide (CP) for 14 days and to immersion in staining beverages for 10 minutes daily. The specimens were divided into the following study groups according to bleaching treatment and staining substance (n=12): G I (negative control): no bleaching + distilled water; G II (positive control): bleaching + distilled water; G III: bleaching + coffee; and G IV: bleaching + grape juice. Twelve volunteers used the device continually, except during meals, oral hygiene, dental bleaching, and pigment challenge. Color readings were performed using a spectrophotometer both before the bleaching treatment and after each treatment week. The results were submitted to the normality test. The data obtained were submitted to analysis of variance and the Tukey or Kruskal-Wallis and Dunn tests (α=0.05). All bleached groups showed similar ΔE results at the end of treatment. Staining beverages generated negative ΔL mean values, and the lowest result was obtained in the treatment with coffee after 14 days. The Δa values in the groups that received treatment with staining beverages were higher when compared to the control groups. Dental bleaching associated with the consumption of staining substances may not affect overall tooth color change by the end of the treatment, although the consumption of staining substances did influence the different color dimensions.

Seven-year clinical performance of resin composite versus resin-modified glass ionomer restorations in noncarious cervical lesions.

PURPOSE: The purpose of this study was to comparatively assess the seven-year clinical performance of a one-bottle etch-and-rinse adhesive with resin composite (RC) and resin-modified glass ionomer (RMGI) restorations in noncarious cervical lesions. METHODS AND MATERIALS: One operator placed 70 restorations (35 restorations in each group) in 30 patients under rubber dam isolation without mechanical preparation. The restorations were directly assessed by two independent examiners, using modified US Public Health Service criteria at baseline and 6, 12, 24, 60, and 84 months. The obtained data were tabulated and statistically analyzed using the Fisher and McNemar tests. A difference was significant if p<0.05. RESULTS: Twenty patients were available for recall after seven years (66.6%), and 25 RC and 26 RMGI restorations out of 70 restorations were evaluated. Excellent agreement was registered for all criteria between examiners (κ≥0.85). Alfa and bravo scores were classified as clinically acceptable. The McNemar test detected significant differences within RC restorations between baseline and seven-year evaluations for anatomic form, marginal integrity, and retention (p<0.05). For RMGI restorations, a significant difference was identified for marginal integrity (p<0.05). As to material comparison, the Fisher exact showed a better retention performance for RMGI restorations than for RC restorations (p<0.05). Twelve composite restorations were dislodged (52.0% retention) and three ionomer restorations were lost (88.5% retention). The cumulative success rate for RC and RMGI was 30% and 58.1%, respectively. CONCLUSIONS: After seven years of service, the clinical performance of RMGI restorations was superior to that of the adhesive system/resin composite restorations in this study.

In vivo dentin remineralization by calcium-phosphate cement.

Minimally invasive caries-removal procedures remove only caries-infected dentin and preserve caries-affected dentin that becomes remineralized. Dental cements containing calcium phosphate promote remineralization. This study evaluated the in vivo remineralization capacity of resin-based calcium-phosphate cement (Ca-P) used for indirect pulp-capping. Carious and sound teeth indicated for extraction were randomly restored with the Ca-P base or without base (control), followed by adhesive restoration. Study teeth were extracted after three months, followed by elemental analysis of the cavity floor. Mineral content of affected or sound dentin at the cavity floor was quantified by electron probe micro-analysis to 100-mum depth. After three months, caries-affected dentin underneath the Ca-P base showed significantly increased calcium and phosphorus content to a depth of 30 mum. Mineral content of treated caries-affected dentin was in the range of healthy dentin, revealing the capacity of Ca-P base to promote remineralization of caries-affected dentin.

Clinical evaluation of two packable posterior composites: 2-year follow-up.

The clinical performance of two packable posterior composites, Alert (A)-Jeneric/Pentron and SureFil (S)-Dentsply, was evaluated in 33 patients. Each patient received one A and one S restoration, resulting in a total of 66 restorations. The restorations were placed by one operator according to the manufacturer's specifications and were finished and polished after 1 week. Photographs were taken at baseline and after 2 years. Two independent evaluators conducted the clinical evaluation by using modified United States Public Health Service criteria. After 2 years, 60 restorations (30 A and 30 S), 27 class I (16 A and 11 S) and 33 class II (14 A and 19 S) were evaluated in 30 patients. Criterion A for recurrent caries, vitality, and retention was applicable to all 60 restorations. Criterion B was distributed among 40 restorations as follows: surface texture (15 A; 2 S), color (5 A; 6 S), postoperative sensitivity (1 S), marginal discoloration (8 A), marginal adaptation (3 A), and wear resistance (2 A). Data were analyzed using the Exact Fisher and McNemar tests. After 2 years, S showed a significantly better performance than A with respect to surface texture and marginal discoloration. The clinical performance of both materials was considered acceptable over the 2-year period. Further evaluations are necessary for a more in-depth analysis.