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Introduction This study radiographically analyzed the prevalence of root canal treatment (RCT) and apical periodontitis (AP) in type 1 diabetes mellitus (T1DM) and nondiabetic individuals and its association with the history/current status of T1DM. Methods In a cross-sectional paired study, the radiographic records of 50 individuals with T1DM and 100 age- and sex-matched nondiabetic subjects were examined. The presence of RCT and AP was evaluated. Information regarding the history and current status of T1DM was collected from the medical records of each patient. Results One or more RCTs were found in 76% and 44% of diabetic and nondiabetic subjects, respectively (P = .000). AP in 1 or more teeth was found in most T1DM patients (58%) and in 15% of the control subjects (P = .000). One or more RCTs associated with AP were found in 52% and 8% of T1DM and nondiabetic subjects, respectively (P = .000). Bivariate logistic regression analyses suggested that RCT (odds ratio [OR] = 10.435, P = .000), AP (OR = 3.508, P = .011), and RCT + AP (OR = 7.220, P = .000) were significantly associated with the presence of T1DM. Multivariate logistic regression showed that among T1DM individuals, there is an association between 11–15 years of diagnosis time and at least 1 RCT (OR = 46.316, P = .038) and an association between T1DM control and at least 1 tooth with AP (OR = 15.611, P = .016). Conclusions RCT, AP, and RCT with AP were more prevalent in individuals with T1DM than in nondiabetic individuals. RCT and AP were associated with the presence of T1DM, specifically RCT with diagnostic time and AP with glycemic control.

Purpose To assess the effect of acid etching (AE) and adhesive systems on the microtensile bond strength of conventional glass ionomer cement (GIC) and a nanofilled composite resin. Materials and methods Specimens of conventional GIC (RIVA, Self-cure, SDI) were prepared in a bipartite Teflon mold and randomly assigned (n=12) to G1- GIC+Single Bond 2 (SB2) (3M-ESPE); G2- GIC+Acid etching (AE) (37% phosphoric acid, Condac, FGM) + SB2; G3- GIC+Single Bond Universal (SBU) (3M-ESPE); and G4- GIC+AE+SBU. The adhesive systems and the composite (Filtek Z350XT, 3M-ESPE) were inserted into the mold. After 7 days stored in a humid environment, the specimens were sectioned into five slices (Isomet 1000, Buehler). Hourglass slices were trimmed and subjected to microtensile bond strength testing (BISCO®; Schaumburg, USA) with 0.5 mm/min crosshead speed. Data were analyzed by two-way ANOVA and the Tukey test (SPSS 17.0, α=5%). Results The microtensile bond strength (MPa) means (standard deviation) were G1=9.46(3.79), G2=6.27(3.21), G3=9.35(3.91), and G4=10.13(3.53). G2 differed significantly from the other groups (p 0.05). There were 83% mixed fractures, 9.5% cohesive and 7.5% adhesive. Conclusion GIC etching promoted higher microtensile bond strength with universal adhesive than with a total-etch adhesive system. Acid etching is not necessary to enhance the universal adhesive bond strength and negatively affected the bond strength of the total-etch adhesive system. Without etching the GIC, there is no difference in microtensile bond strength between the adhesive systems.

Statement of problem Decementation is one of the most frequent causes of failure in the post-cement system. The bond strength in different parts of the canal may be influenced by technical and anatomic factors. Purpose The purpose of this in vitro study was to assess the effects of anatomic root levels to reach the canal and different resin cements on the bond strength of fiberglass posts along the canal. Material and methods One hundred thirty-five roots of bovine teeth were endodontically treated, prepared with 15-mm-long post spaces and divided according to the anatomic root level: coronal (with 15-mm post space), middle (with 10-mm post space), and apical (with 5-mm post space). Fiberglass posts were luted with the cements (n=15): conventional resin cement with 3-step etch-and-rinse adhesive system (RelyX ARC/SBMP); self-adhesive resin cement (RelyX U200) and autopolymerizing resin cement with etch-and-rinse adhesive system (C&B/All-Bond 2). After 24 hours, specimens were sectioned and subjected to the push-out test. The maximum extrusion load was recorded (0.5 mm/minute, 200 N). Data were analyzed with analysis of variance (ANOVA) and the Tukey test (α=.05). Failure mode was analyzed by using multinomial logistic regression. Results There were no significant effects of resin cements ( P >.05). The bond strength at apical third was higher when the canal was reached at the apical level than at the coronal level ( P =.022). When each root level was directly reached, the coronal bond strength was lower than apical ( P =.001) and middle ( P =.021) for all cements. Conclusions When the canal was reached at the coronal, medium, and apical levels, the bond strength of conventional, self-adhesive and autopolymerizing resin cements was lower in the coronal root third.

Statement of problem The mechanical stability of the prosthetic components in the implant-prosthesis complex is essential to the long-term success of the restorations. However, little is known about the differences in the biomechanical behavior of screw- and cement-retained prostheses. Purpose The purpose of this study was to compare the preload maintenance, stresses, and displacements of prosthetic components of screw- and cement-retained implant-supported prostheses by using the finite element method in a nonlinear analysis. Material and methods Two 3-dimensional models were constructed: implant-supported fixed partial prostheses with 3 elements retained either by screws (SFP) or cement (CFP). After the simulation of screw tightening, the preload was calculated for both prostheses. Then vertical and oblique loads (100 N) were applied on the models. The preload was identified, the maximum von Mises equivalent stresses (SEQV) were obtained on the screws, and the displacement among the abutment, the implant, and screw was identified by observing the penetration and gap in the contact interfaces. Results Under vertical load, there was a higher decrease in the preload and in the SEQV on the screw in the SFP. Under oblique load, the SEQV was 24% higher on the screw of the SFP. In the displacement analysis under vertical load, penetration was concentrated in the threads of the screw in the SFP and between the abutment and implant in the CFP. The gap was 118% greater for the SFP and was concentrated on the abutment extension. Under oblique load, the displacement pattern was similar for both prostheses, but with values 66% higher for penetration and 96% higher for gap for the SFP. Conclusions The SFP showed a higher biomechanical risk of failure than the CFP.

This study aimed to systematically review the scientific evidence for the association between noncarious cervical lesions (NCCL) and occlusal risk factors (ORF) [occlusal interferences in excursive movements; occlusal force; premature contacts; type of guidance; skid of centric occlusion to maximum intercuspidation] in adults.Pubmed, Web of Science, Cochrane, Lilacs, Clinical Trials, National Research Register and National Institute for Health were searched.From 1082 potentially eligible studies, 106 were selected for full text analysis. Two independent reviewers (Kappa=0.8; p0.001) selected the studies, abstracted information and assessed quality based on standardised scales. Six cross-sectional, two case-controls and one clinical trial were included. Several occlusal variables were analysed among the studies, but there was no standardisation of the units used in the analysis of occlusal factors. The majority of studies did not find significant associations between NCCL and ORF. Three studies found associations between NCCL and some variables (occlusal contact area, right canine guidance, premature contacts in centric relation and working side) (p0.05). The methodological quality varied across studies, and there was high heterogeneity among them.Current scientific evidence does not support an association between ORF and NCCL. Further prospective studies with standardised methods are vital to strengthen the evidence.Understanding the risk factors for NCCL is important to control the causes and to help the dentist choose the best approach for the patient. The evidence does not support intervention to alter some occlusal factors for the prevention or control of the progression of NCCL.

Objective . The aim of this in vitro study was to evaluate the interaction between two sources of fluoride (restorative systems and dentifrices) in inhibiting artificial root caries development. Methods . One hundred and eighty tooth segments were embedded in polyester resin, and sanded flat. Cylindrical cavities 1.0 mm-deep and 1.5 mm-diameter were prepared in root dentin and randomly restored by fluoride-containing restorative systems: Ketac-fil/Espe (Ke), Fuji II LC/GC Corp (Fj), F2000/3M (F2), Surefil/Dentsply (Su) or a control: Filtek Z250/3M (Z2). Ten experimental groups were made to test the association among the five restorative systems and two dentifrices: with F − (Sensodyne Baking Soda) or without F − (Sensodyne Original) ( n =18). After surface polishing, a 1 mm-wide margin around the restorations was demarcated and initial dentin surface Knoop microhardness values (KHN i ) were obtained. The specimens were submitted to a pH-cycling model, and to applications of slurries of dentifrice. Afterwards the final dentin surface Knoop microhardness values (KHN f ) were measured. Results . The differences between KHN i and KHN f , and the covariate KHN i were considered by the ANCOVA and Tukey's test ( α =0.05). The interaction between restorative system and dentifrice was statistically significant ( p =0.0026). All restorative systems provided some protection against artificial caries challenge when associated with the fluoride-containing dentifrice treatment. The means (standard deviation) of reductions in Knoop hardness values for systems associated with the fluoride-containing dentifrice were: Ke: 40.0(1.02) a , Fj: 41.9(1.02) b , F2: 43.3(1.04) c , Su: 43.5(1.00) c , Z2: 44.0(1.02) c ; and with the non-fluoride-containing dentifrice were: Ke: 42.9(1.02) a , Fj: 44.7(1.01) b , F2: 45.2(1.09) bc , Su: 46.0(0.99) c , Z2: 46.6(0.99) c (statistical differences were expressed by different letters). Conclusion . The cariostatic effect shown by the fluoride-containing dentifrice could enhance that shown by Ketac-fil and Fuji II LC, and could mask that shown by F2000.