Marilisa Carneiro Leão Gabardo

Influence of Cervical and Apical Enlargement Associated with the WaveOne System on the Transportation and Centralization of Endodontic Preparations.

INTRODUCTION The aim of this study was to evaluate through computed microtomography the transportation and centralization of root canals instrumented using the WaveOne system (Dentsply Maillefer, Ballaigues, Switzerland) associated or unassociated with previous apical and cervical enlargements. METHODS Thirty-six mandibular molars were selected with independent mesial roots and curvatures and randomized into the following groups: PathFile (Dentsply Maillefer) before WaveOne Primary (the PFWO group), ProTaper Universal SX (Dentsply Maillefer) before WaveOne Primary (the SXWO group), and WaveOne Primary (the WO group). Computed microtomographic imaging was performed pre- and postpreparation to obtain measurements of mesial and distal dentin walls and calculations of root canal transportation (%) and centralization. One-way analysis of variance was performed to compare the different groups, repeated measures analysis of variance for comparison of the root thirds in each group, and the Student t test for comparisons between the mesiobuccal and mesiolingual canals. RESULTS Transportation of the cervical and middle thirds to the danger zone was observed in both roots, whereas the apical thirds were transported to the outer face of the curvature. In the PFWO and SXWO groups, less transportation was observed in the middle thirds of the mesiobuccal canals compared with the WO group (P < .05). Centralization remained almost unchanged in the SXWO group (P < .05). CONCLUSIONS In each group, transportation toward the danger zone was mostly observed in the cervical thirds of the mesiobuccal canals. Cervical or apical enlargement resulted in reduced transportation and improved centralization of the middle thirds compared with the exclusive use of the WaveOne system.

Efficacy of Different Cone-beam Computed Tomographic Protocols in the Identification of Mesiobuccal Canals of Maxillary First Molars: A Tomographic and Ex Vivo Study

Introduction: Complementary methods of anatomic diagnosis, including cone‐beam computed tomographic (CBCT) imaging, may be useful in the diagnosis of mesiobuccal (MB) canals of maxillary molars. Methods: Thirty‐five maxillary first molars were subjected to ex vivo analysis and 4 CBCT protocols: i‐CAT Classic (Imaging Sciences International, Hatfield, PA) (ICC group), i‐CAT Next Generation (Imaging Sciences International) (ICN group), PreXion 3D (PreXion, San Mateo, CA) (16.8‐second acquisition time; PX1 group), and PreXion 3D (33.5‐second acquisition time; PX2 group). The images were evaluated by 2 calibrated endodontists who kept records following protocols previously published in the literature. Micro–computed tomographic imaging was used as the control. Results: The correct identification of anatomic variations of MB roots was 54.3% (n = 19) in the ICC group, 65.7% (n = 23) in the ICN group, and 80.0% (n = 28) in the PX1 and PX2 groups. The probability of agreement between the ICC and the control groups was significantly different from the probability of agreement with the PX1 (P < .05) and PX2 (P < .05) groups. The other groups showed no significant differences compared with the control group. There was no difference in the probability of agreement between the tomographic protocols and the ex vivo results. Conclusions: The PX1 and PX2 groups were more effective for the diagnosis of MB canals. PX1 is the most suitable because it results in a shorter radiation time and diagnostic imaging similar to PX2. The single‐canal anatomy was the most prevalent in the study. HIGHLIGHTSThe i‐CAT Classic protocol resulted in fewer diagnoses of mesiobuccal (MB) canals of maxillary molars.The PreXion 3‐dimensional protocols were more effective for the diagnosis of MB canals of maxillary molars.There was no difference in the probability of agreement between the tomographic protocols and the ex vivo result.Type I anatomy was the most prevalent in this study.

Perfil sociodemográfico e condição bucal de usuários de drogas em dois municípios do Estado do Paraná, Brasil

IntroductionEpidemiological survey of the oral conditions of drug users is an important strategy to know this population, whose growth is increasing in Brazil, so that preventive goals and adequate treatment can be proposed.AimThe aim of this study was to identify the sociodemographic profile and oral health condition of drug users in rehab of two municipalities of the State of Parana.Material and methodOne hundred individuals participated in the study, which data were collected by questionnaire and physical exam. The following values were obtained: DMFT index (decay-missing-filled index), probing depth (PD), clinical attachment level (CAL), gingival index (GI), plaque index (PI), and bleeding on probing (BOP). Data analyses were performed by Student t test and one-way ANOVA.ResultThe mean age of participants was 29.12 years. The major frequencies were: male (95.5%), single (69.0%), lower schooling (41%) and higher consumption of licit drugs tobacco (90.9%) and alcohol (84.5%), followed by crack (80.9%), and marijuana (77.3%). The mean DMFT index was 15.21 (SD=5.84), and the longer the dependence time, the greater this index (p<0.05). Mean PD was 3.55 and mean CAL was 3.59. BOP occurred in 82.7% and 79.5% showed moderate inflammation. Detectable plaque and moderate plaque accumulation were observed in 39.5% and 35.3%, respectively.ConclusionPrevalence was observed in young and single males with low schooling, and with consumption of licit and illicit drugs. Poor oral health condition was identified, which deserves more attention from health professional and policymakers for this population.

Root Preparation of Deciduous Teeth: Efficacy of WaveOne and ProTaper Systems with and without Passive Ultrasonic Irrigation

Introduction: The aim of this study was to compare root preparation of deciduous teeth with WaveOne Large (WO) and ProTaper F4 (PT) instruments with or without passive ultrasonic irrigation (PUI). Methods and Materials: Forty-eight deciduous teeth were scanned before and after root preparation and divided in four groups (n=12): WO+EDTA (WO); WO+EDTA with PUI (WOPUI); PTF+EDTA (PT); and PT+EDTA with PUI (PTPUI). Root canal enlargement by micro-computed tomography and root canal cleaning by scanning electron microscopy (SEM) were analyzed. Data were submitted to two-way ANOVA and Tukey’s tests to analyze the root canal volume variation, and Kruskal-Wallis followed by Friedman and Wilcoxon tests were used to evaluate the cleaning efficacy. The level of significance was set at 0.05. Results: No significant difference occurred in total volume between groups (P>0.05). On analysis by thirds of the root canal, there was a difference in volume between WO (cervical) compared to WO and PT (apical), and PTPUI (middle and apical) (P<0.05). When cleaning of the thirds within the same group was compared, there was a significant difference in all groups (P<0.05). Among the groups, in the thirds, in the cervical a difference occurred (P=0.028), and the pairwise comparisons indicated statistically difference between WO and PT, and WO and PTPUI (P<0.05). In the pairwise comparisons among thirds, in the groups, difrences occured in all of them when compared the cervical and apical thirds (P<0.05). Conclusion: Passive ultrasonic irrigation has not improved the smear layer removal in deciduous teeth. Despite the differences in performance between WO and PT instruments, both were suitable for preparation of deciduous teeth.

In vitro evaluation of gutta-percha dissolution ability of different solvents

Introduction: The removal of the filling material during the Endodontic retreatment is essential, so a better action of solvents on the gutta-percha is desired. Objective: To evaluate in vitro the gutta-percha dissolution ability of different solvents. Material and methods: Four solvents (xylol, eucalyptol, citrol, and orange oil) were applied on gutta-percha points, which had been later submitted to the weight loss analysis at 2, 5, and 10 minutes. For each solvent, 30 size #60 main cones were used, divided into three groups. Distilled water was used as control group. The statistical test applied was Kruskal-Wallis. Results: No statistically significant difference occurred among the solvents at 2 minutes (p > 0.05); however, during this period, citrol had the best performance. In longer time intervals, the xylol showed differences compared to eucalyptol at 5 minutes and to eucalyptol and citrol at 10 minutes (p < 0.05). The worst results were found for eucalyptol. Conclusion: This xylol was the solvent with improved ability to dissolve the gutta-percha points, with better results at longer time periods.