The aim of this study was to evaluate the effect of silanization protocols on the bond strength of two resin cements to a lithium disilicate glass-ceramic. Thirty-two ceramic discs were assigned to 2 groups (n=16): G1 -dual-cured resin cement and G2 -lightcured resin cement. Four subgroups were evaluated according to the used silanization protocol. The glass-ceramic was etched with 10% hydrofluoric acid for 20 s and silane was applied for 1 min, as follows: CTL -according to the manufacturer's instructions; HA -dried with hot air; NWA -washed and dried with water and air at room temperature; HWA -washed and dried with hot water and hot air. Thereafter, adhesive was applied and light-cured for 20 s. Silicon molds were used to prepare resin cement cylinders (1x1 mm) on the ceramic surface. The specimens were stored in deionized water at 37 °C for 48 h and subjected to a micro-shear test. The data were submitted to statistical analysis (α=0.05). Group G1 showed higher bond strengths than G2, except for the CTL and NWA subgroups. Differences as function of the silanization protocol were only observed in G1: HWA (25.13±6.83)≥HA (22.95±7.78)≥CTL(17.44±7.24) ≥NWA(14.63±8.76). For G2 there was no difference among the subgroups. In conclusion, the silanization protocol affected the resin cement/ceramic bond strengths, depending on the material. Washing/drying with hot water and/or hot air increased only the bond strength of the dual-cured resin cement.S i l a n a t e d S u r f a c e T r e a t m e n t : Effects on the Bond Strength to Lithium Disilicate Glass-Ceramic

Objective: To evaluate if genetic polymorphisms in the oestrogen receptor 1 ( ESR1) and oestrogen receptor 2 ( ESR2) genes encoded for oestrogen receptors alpha (ERα) and beta (ERβ) are involved in permanent tooth size. Design: Cross-sectional study. Setting: Orthodontic Clinic at School of Dentistry of Ribeirão Preto, University of São Paulo. Participants: A total of 108 orthodontic patients. Materials and Methods: Pre-treatment orthodontic records were evaluated. Dental casts were used to determine the maximum crown measurements of fully erupted permanent teeth in the mesiodistal dimensions. Second and third molars were not included in the analysis. Genomic DNA samples were used for the genotyping of four genetic polymorphisms: ESR1 (rs9340799 and rs2234693) and ESR2 (rs1256049 and rs4986938). The associations between tooth size and sex were evaluated using t test. The associations between tooth size and genotype were analysed with linear regression and adjusted by sex at an alpha of P⩽0.05. Results: Female patients presented smaller tooth size than male patients. A statistically significant difference was observed in almost all teeth ( P<0.05). The genetic polymorphisms in rs9340799, rs2234693, rs1256049 and rs4986938 were associated with some tooth sizes in both the maxilla and mandible ( P<0.05). Conclusion: This study provides evidence that genetic polymorphisms in ESR1 and ESR2 could be associated with tooth size in permanent teeth.

The influence of root canal filling techniques on the penetration of AH Plus into dentinal tubules was evaluated using confocal laser scanning microscopy (CLSM) and the impact on the bond strength of the filling material on the root dentin was evaluated using the push-out test. Roots of the maxillary central incisors (n=40) were prepared with ProTaper Universal and assigned to four groups: lateral condensation, vertical compaction, modified Tagger hybrid and single cone. After root canal filling with gutta-percha and AH Plus, along with the addition of 0.01% fluorescein, the roots were cut into 2-mm slices. CLSM was performed on the first slice of each root third, followed by the push-out test. The second slice was analyzed under SEM. ANOVA demonstrated a statistically significant difference between the root canal filling techniques and the root thirds (p<0.05). For percent penetration, Tukey's test showed that the vertical compaction (91.77±13.51), lateral condensation (89.18±10.91) and modified Tagger hybrid (87.53±15.42) presented the highest values, which significantly differed (p<0.05) from those of the single cone (78.19±22.46). For bond strength (MPa), lateral condensation (3.42±0.54) and vertical compaction (3.47±0.53) had the highest values (p<0.05), while the modified Tagger hybrid (2.19±0.41) and single cone (0.54±0.21) had the lowest. In conclusion, the lateral condensation, vertical compaction and Modified Tagger's hybrid techniques resulted in greater penetration and bond strength to the intra-radicular dentin.

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In this study, curved maxillary molar root canals were instrumented with RaCe rotary system to evaluate: 1. the occurrence of canal transportation using a radiographic platform; 2. the action of the instruments on the dentin walls, centering ability and canal enlargement by analysis of digital images; and the percentage of regular dentin surfaces and debris within the canal by histological analysis. Ten mesiobuccal roots of extracted human maxillary molars were embedded in acrylic resin and sectioned at the middle and apical thirds. Root canal shaping was performed using the RaCe rotary system at 250 rpm and 1 Ncm torque. Each instrument set was used five times according to a crowndown technique in the following sequence: 40/0.10, 35/0.08, 25/0.06, 25/0.04, 25/0.02 (working length -WL), 30/0.02 (WL) and 35/0.02 (WL). Each instrument was inserted until resistance was felt and then pulled back, followed by brushing movements towards all canal walls. Each specimen was assessed by three study methods: radiographic platform, digitized image assessment and histological analysis. The radiographic platform showed lack of apical transportation. No statistically significant difference (Wilcoxon test, p>0.05) was found between the middle and apical thirds regarding instrument action on dentin walls, centering ability, area of root canal enlargement, percentage of regular dentin surfaces and debris within the root canal. It may be concluded that RaCe system is a suitable method for the preparation of curved root canals, regarding the maintenance of root canal original path, action on dentin walls, canal enlargement and removal of debris from the root canal lumen.

Background: Temporomandibular joint disorder (TMD) can significantly affect the quality of life of individuals. However, evidence of TMD involvement and the extent of the impacts caused by it, in groups exposed to a stressful routine, are still scarce. Therefore, the aim of the present study was to evaluate the prevalence of TMD signs and symptoms and their impact on quality of life related to oral health in construction workers. Material and methods: This cross-sectional study included only male individuals. Illiterate workers and functional illiterate were excluded. The diagnosis of TMD was established according to the Research Diagnostic Criteria for TMD (RDC/TMD). The Oral Health Impact Profile questionnaire validated for Portuguese (OHIP-14) was used to assess the impact of TMD on oral health and quality of life. Descriptive analysis of TMD signs and symptoms was performed. Data related to the OHIP-14 questionnaire were compared using the Mann-Whitney U test. Pearson's correlation was also performed. The established alpha of this study was 5%. Results: 230 individuals were included. The mean age was 37.8 (SD=11) years. The most frequent TMD sign and the symptom was disc displacement, 86 (37.39%) of the individuals. OHIP-14 demonstrated a statistically significant difference when

Introduction: The final color of dental ceramics depends on different factors such as light source, substrate, and selected material (thickness, contour, and texture). Objective: to report a clinical case in which a predictable protocol is used to optimize the final color of porcelain laminate veneers Case report:: A male patient attended the dental clinic dissatisfied with the composite resin restorations made on his upper anterior teeth. After anamnesis and clinical examination, it was suggested that the resin restorations be replaced by laminated porcelain veneers. A diagnostic wax-up was performed. The mock-up was also used to evaluate the aesthetic length for replicating the details of the incisal edge and the shape and size of the embrasures. The shade was selected before composite resin removal to avoid dehydration of the dental substrate. A photograph was taken to guide the selection of colors in different thirds. After removing the restorations, another photograph was taken to evaluate the color of the substrate. The impression was taken with 000 retractor wire and addition silicone. The laminates were made with pressed ceramic and feldspathic porcelain veneers were subsequently applied by layering the layers of dentin, incisal edge and enamel based on the waxing diagnosis. After approval by the patient, a conventional cementation technique was performed. The occlusal adjustment was made with rubber polishing cups and the anterior and lateral guides were checked. Conclusion: The protocol recommended for successful selection of the color of a porcelain laminate relies on the combination of knowledge of concepts, resources such as shade guides, spectrophotometers, and photographs, and porcelain application and characterization techniques performed by the technician and luting techniques by the dentist.

The study aimed to explore the influence of genetic polymorphisms in ANKK1 and DRD2 on the signs and symptoms of temporomandibular disorder (TMD) in construction workers. This cross-sectional study included only male subjects. All construction workers were healthy and over 18 years age. Illiterate workers and functionally illiterate workers were excluded. The diagnosis of TMD was established according to the Research Diagnostic Criteria for TMD (RDC/TMD). Genomic DNA was used to evaluate the genetic polymorphisms ANKK1 (rs1800497) and DRD2 (rs6275; rs6276) using Real-Time PCR. Chi-square or Fisher exact tests were used to evaluate genotypes and allele distribution among the studied phenotypes. The established alpha of this study was 5%. The sample included a total of 115 patients. The age of the patients ranged from 19 to 70 years (mean age 38.2; standard deviation 11.7). Chronic pain (87.7%), disc displacement (38.2%), and joint inflammation (26.9%) were the most frequently observed signs and symptoms. The genetic polymorphism rs6276 in DRD2 was associated with chronic pain (p=0.033). In conclusion, our study suggests that genetic polymorphisms in DRD2 and ANKK1 may influence TMD signs and symptoms in a group of male construction workers.