Postoperative pain intensity after using different instrumentation techniques: a randomized clinical study

Abstract Postoperative pain is a frequent complication associated with root canal treatment, especially during apical instrumentation of tooth with preexisting periradicular inflammation Objectives The aim of this clinical study was to evaluate the influence of the instrumentation techniques on the incidence and intensity of postoperative pain in single-visit root canal treatment. Material and Methods Ninety patients with single root/canal and non-vital pulps were included. The patients were assigned into 3 groups according to root canal instrumentation technique used; modified step-back, reciprocal, and rotational techniques. Root canal treatment was carried out in a single visit and the severity of postoperative pain was assessed via 4-point pain intensity scale. All the participants were called through the phone at 12, 24 and 48 h to obtain the pain scores. Data were analyzed through the Kruskal–Wallis test. Results There was significant difference between all groups (p<0.05). The modified step-back technique produced postoperative pain significantly lower than the rotational (p=0.018) and reciprocal (p=0.020) techniques. No difference was found between the reciprocal and rotational techniques (p=0.868). Postoperative pain in the first 12 h period (p=0.763) and in the 24 h period (p=0.147) was not significantly different between the groups. However, the difference in the 48 h period was statistically different between the groups (p=0.040). Conclusion All instrumentation techniques caused postoperative pain. The modified step-back technique produced less pain compared to the rotational and reciprocal techniques.

Effects of Different Rotary Files Combined with Different Irrigation Needles on Apically Extruded Debris

The aim of this study was to compare the apically extruded debris associated with ProTaper Next and OneShape Apical files using two different irrigation needles, open-ended and closed-ended (Max-I-Probe). Forty-eight mandibular premolars were assigned to four groups (n=12) as follows: Group PTN-SN: Root canal was prepared with ProTaper Next (PTN) and irrigated with open-ended standard needle; Group PTN-MP: Root canal was prepared with PTN and irrigated with Max-I-Probe; Group OSA-SN: Root canal was prepared with OneShape Apical (OSA) and irrigated with open-ended needle; Group OSA-MP: Root canal was prepared with OSA and irrigated with Max-I-Probe. Debris extruded during instrumentation was collected into pre-weighed Eppendorf tubes. After storage in an incubator at 70 °C for 5 days, the Eppendorf tubes were weighed to obtain the final weight with extruded debris. The difference between pre-and post-debris weights was calculated and statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U tests (p<0.05). No statistically significant difference was observed between files and needles regarding amount of apically extruded debris (p>0.05). OneShape Apical and ProTaper Next resulted in extrusion of debris beyond the apical foramen, regardless of needle tip.

O objetivo do presente estudo foi comparar a extrusão apical de restos de preparação de canais, associada às brocas ProTaper Next e OneShape Apical usando duas agulhas de irrigação, de ponta aberta e ponta fechada (Max-I-Probe). Quarenta e oito premolares inferiores foram divididos em quatro grupos (n=12): Grupo PTN-SN: o canal radicular foi preparado com ProTaper Next (PTN) e irrigado com agulha convencional de ponta aberta; Grupo PTN-MP: o canal radicular foi preparado com PTN e irrigado com Max-I-Probe; Grupo OSA-SN: o canal radicular foi preparado com OneShape Apical (OSA) e irrigado com agulha de ponta aberta; Grupo OSA-MP: o canal radicular foi preparado com OSA e irrigado com Max-I-Probe. Os restos extrudados apicalmente foram coletados em tubos Eppendorf previamente pesados. Após armazenagem por cinco dias a 70 °C, os tubos Eppendorf foram pesados para obter o peso final com os resíduos. A diferença entre as pesagens antes e depois foi calculada e análise estatística foi feita usando os testes de Kruskal-Wallis e Mann-Whitney U (p<0,05). Não houve diferença estatisticamente significante entre as brocas e agulhas com relação à quantidade de resíduos extrudados (p>0,05). As brocas ProTaper Next e OneShape Apical promoveram extrusão além do forame apical, independente do tipo de agulha utilizada.