RESUMO
INTRODUCTION: Different techniques have been proposed to help achieving apical patency during endodontic treatment and retreatment. The objective of this in vitro study was to compare reestablishment of apical patency in teeth previously subjected to root canal treatment using manual and reciprocating instruments. METHODS AND MATERIALS: A total of 40 single-rooted extracted human mandibular incisors were selected and prepared using the Hero 642 sequence to 45/0.02 and obturated using Tagger's hybrid technique to 1 mm short of the apex. Teeth were divided into two groups according to the type of instrument used to regain patency: group 1, hand K-files and group 2, reciprocating WaveOne Primary files (25/0.08). Fisher's exact test was used in the statistical analysis. Result: In group1, apical patency was regained in 9 of the 20 teeth tested (46%), compared to 20 teeth (100%) in group 2. The difference between the groups was significant (P<0.0001). CONCLUSION: Our study shows that reciprocating instrumentation is more successful in regaining apical patency in single-rooted, previously treated teeth.
RESUMO
Frente ao insucesso endodôntico, a primeira opção de tratamento é a reintervenção ou retratamento do canal radicular. Poucos estudos têm trabalhado a temática da experiência do operador no tempo dessa intervenção. Diante dessa lacuna, o presente estudo objetivou avaliar o tempo para atingir o comprimento de trabalho na desobturação de canais radiculares por três operadores. Foram selecionados quarenta e cinco dentes humanos extraídos, uniradiculares, previamente preparados e obturados e, após o envelhecimento do material obturador, submetidos ao método de desobturação com os instrumentos ProTaper Universal Retratamento por diferentes operadores, levando em consideração a sua experiência - um especialista em Endodontia, um aluno de especialização em Endodontia e um aluno de graduação. Os resultados obtidos mostraram que o tempo foi significativamente diferente entre os grupos (p = 0,02); e que o CT não teve diferença estatisticamente significativa no tempo obtido para desobturação (p = 0,05). Como conclusão, houve diferença no tempo para a obtenção do comprimento de trabalho entre os operadores, sendo que o especialista e o aluno de especialização levaram menos tempo para chegar ao comprimento de trabalho do que o aluno de graduação (AU).
When facing endodontic treatment failure, the first treatment option is the reintervention or retreatment of the root canal. Few studies have worked with the issue related to operator experience in the intervention timeline. Due to this gap, this study evaluated the time to accomplish working length of root canals desobturation by three operators. Forty-five extracted uniradiculars human teeth were selected, previously prepared and filled and after aging of the filling material, they were submitted to the desobturation method with ProTaper Universal Retreatment instruments by different operators, taking into account their experience - an Endodontics specialist, a student of Endodontics specialization and an undergraduate student. The results showed that the time was significantly different between groups (p = 0.02); and WL had no statistically significant difference in the time obtained for desobturation (p = 0.05). In conclusion, there was difference in the time to obtain the working length between the operators, as the specialist and the specialization student took less time to reach the working length than the graduate student (AU).
