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Aim: This study evaluated the effectiveness of the mechanical reduction of intracanal bacteria produced by the endodontic systems Reciproc Blue (VDW GmbH), XP-Endo Shaper (FKG Dentaire) and ProTaper Next (Dentsply Sirona Endodontics) in severely curved canals by culture analysis. Methodology: Fifty severely curved mesiobuccal canals of mandibular molars were selected and instrumented. Following this, six specimens were selected as control, while 44 canals were contaminated with Enterococcus faecalis strains (ATCC 29212). Specimens were incubated for 21 days at 37 ºC. Then, contaminated specimens were randomly divided into 3 groups (n=14): ProTaper Next (G1), XP-Endo Shaper (G2) and Reciproc Blue (G3). Control Group: Six non-contaminated canals were prepared with one of the 3 file systems (n=2). Microbial samples were obtained before (S1) and after root canal preparation (S2). Two roots were observed using scanning electron microscopy to verify biofilm formation.  Quantitative culture analyses of intracanal E. faecalis reduction was performed using CFUs, and the Wilcoxon test was used for intragroup analysis, and intergroup analysis was performed using Kruskal-Wallis test. The level of significance for all analyses was set at P < .05. Results: All systems presented effective bacterial reduction (p<0.05), but still had bacterial growth. ProTaper Next displayed the highest E. faecalis reduction (P<0.05), while XP-Endo Shaper and Reciproc Blue systems presented similar results (P>0.05). ProTaper Next showed the greatest antibacterial action when compared to the XP-Endo Shaper and Reciproc Blue systems. Conclusion: No instrumentation system rendered root canals completely free from bacteria.

Aim: In this study was evaluated the fracture resistance of endodontically treated maxillary premolars restored with      different restorative materials. Methods: Sixty maxillary premolars were submitted to the same mesio-occlusal-distal cavity preparation, endodontic treatment and divided into 5 groups (n = 10): Coltosol Group – GCO restored with calcium silicate material; Glass Ionomer Cement Group – GGIC, restored with Maxxion R; Modified Glass Ionomer Cement – GMGIC, restored with Gold Label 2; Composite Group - GC, restored with Z100, and the positive control group (GP) - left unrestored. One group remained intact (n=10) serving as negative control (GN). Samples were subjected to fracture resistance testing by the universal testing machine until fracture occurred and was registered in newtons (N). Fracture pattern was assessed and described as favorable or unfavorable. The results were statistically analyzed by 1-way analysis of variance and the post hoc Tukey test with significant statistical difference at P < 0.05.  Results: Higher fracture resistance results were found for GC (1,128.35 ± 249.17), GMGIC (1,250.77 ± 173.29), and GN (1,277.22 ± 433.44) (P < .05). More favorable fractures were observed in the GCO (6), GC (7), and GN (7) (P < .05). Conclusion: Teeth restored with composite and modified GIC presented the same resistance as intact teeth. Teeth restored with Coltosol and GGIC presented similar resistance to unrestored teeth.

Objetivo: Avaliar, por meio de tomografia computadorizada de feixe cônico (TCFC), a morfologia dos canais radiculares de dentes incisivos inferiores, em uma população da região Sudeste brasileira, e sua relação com a idade e o sexo dos pacientes Métodos: Foram analisados 371 prontuários de pacientes de ambos os sexos que continham exames de TCFC, totalizando 1.484 dentes incisivos inferiores. As imagens tomográficas foram capturadas com o tomógrafo Orthopantomograph OP300, com voxel de 0,20mm. A morfologia dos dentes foi avaliada de acordo com a classificação de Vertucci, e foram investigados os efeitos do sexo e da idade dos pacientes sobre a variação na morfologia desses dentes. Resultados: Todos os dentes avaliados apresentaram apenas uma raiz; 80,7% dos incisivos inferiores apresentaram um único canal (Tipo I de Vertucci). O segundo canal esteve presente em 19,3% dos casos, sendo do Tipo II de Vertucci em 1,1%, Tipo III em 18,1%, Tipo IV em 0,1% e Tipo V em 0,1%. Não houve influência estatisticamente significativa (p=0,890) do sexo na morfologia dos incisivos inferiores. Dentro da faixa etária analisada, os indivíduos com menos de 18 anos e aqueles com 40 a 49 anos (28,2% e 26,8% respectivamente) apresentaram significância estatística (p=0,001) quanto à presença de segundo canal, compa- rados aos de outras faixas etárias. Conclusões: A morfologia mais prevalente foi a Tipo I de Vertucci, seguida pelo Tipo III, sem diferença entre os sexos, e com maior prevalência de variação morfológica nos indivíduos com menos de 18 anos e com 40 a 49 anos de idade.