Apical extrusion of debris by manual and mechanical instrumentation

The aim of the present study was to assess the presence of apically extruded debris and evaluate the influence of canal curvature on the amount of debris produced by manual and mechanical techniques. Forty single-rooted mature teeth with 15 to 30 degree of root canal curvature were selected. The presence of only one foramen was confirmed using a magnifying lens. A size 15 K-file was placed up to the apical foramen to determine the patency. Working length was determined with the same instrument, 1 mm short of the foramen. According to the employed technique, the groups were labeled as follows: Group 1 - Manual instrumentation with Mor-flex files; Group 2 - Mechanical instrumentation with Cursor and Mor-flex files; Group 3 - Manual instrumentation with Flexi-cut files; Group 4 - Mechanical instrumentation with Cursor and Flexi-cut files. During instrumentation, the root canals were irrigated with 20 mL. Debris extruded through the apical foramen was collected using the Myers and Montgomery technique. The values (in mg) were: Group 1: 0.422 ± 0.683; Group 2: 0.688 ± 0.795; Group 3: 0.409 ± 0.323; Group 4: 0.810 ± 0.708. Data were analyzed statistically by ANOVA at 5 percent significance level. There was no statistically significant difference among the groups (p<0.05). No statistically significant differences were found between slight and moderate curvatures in terms of the amount of extruded debris (p>0.05).

O objetivo deste trabalho foi registrar a presença de material extruído apicalmente e estudar a influência da curvatura dos canais radiculares na quantidade de material, após a instrumentação manual e mecânica. Foram selecionados 40 dentes uniradiculares com ápice maduro, com curvatura do canal entre 15 e 30 graus e somente um forame apical. Verificou-se a patência do forame usando uma lima tipo-K no. 15 e se determinou a extensão de trabalho a 1 mm do forame. Considerando a técnica empregada, se formaram os seguintes grupos: Grupo 1 - instrumentação manual com limas Mor-flex; Grupo 2 - instrumentação mecânica com Cursor e limas Mor-flex; Grupo 3 - instrumentação manual com limas Flexi-cut e Grupo 4 - instrumentação mecânica com Cursor e limas Flexi-cut. Cada canal foi irrigado, enquanto era preparado, com 20 mL de água destilada. Para a coleta do material se aplicou a técnica proposta por Myers e Montgomery. Os valores, em miligramas obtidos em cada grupo foram: Grupo 1 - 0,422 ± 0,683; Grupo 2 - 0,688 ± 0,795; Grupo 3 - 0,409 ± 0,323 e Grupo 4 - 0,810 ± 0,708. A análise estatística (ANOVA) não detectou diferenças estatisticamente significantes (p> 0,05) nas quantidades médias de material extruído em cada grupo. Comparando a influência da curvatura dos canais, não se encontrou diferenças estatisticamente significantes nas quantidades médias de material extruído segundo as curvaturas foram leves ou moderadas (test t para variâncias desiguais p>0,05).

Root surface roughness following mechanical instrumentation in vivo and in vitro SEM study / 대한치주과학회지

Adequate root preparation in the treatment of periodontal disease often involves mechanical instrumentation to remove plaque, calculus perhaps contaminated cementum. Although meticulous scaling and root planing may remove some cementum, the use of aggressive root planing to remove cementum does not appear warranted. So ultrasonic device and rotary instrument appear to be replacing hand instrument. But it is not clear those instruments make smooth root surface as hand instrument. The roghness of the root surface were evaluate with SEM following instrumentation with Gracey curette, Perio Clean and piezo ultrasonic device(Setlec) with various tip. 20 extracted teeth were used in vitro experiment, and 9 teeth of a patient destined for extraction for periodontal reasons were utilized in vivo experiment. It was demonstrated that hand curette created the smoothest surface, while diamond tip tended to roughen the root surface. But the hand curette, Perio Clean, and piezo ultasonic device with scaler tip tend to remove cementum completely. Piezo ultrasonic device with curette-like tip made the desirable smooth surface with partial removal of cementum.