Effect of guided conservative endodontic access and different file kinematics on debris extrusion in mesial root of the mandibular molars: An in vitro study.

BACKGROUND: Guided conservative endodontic access is a novel technique and the influence of such access cavities on apical debris extrusion (ADE) can have a significant effect on postoperative pain.

OBJECTIVE: This study compared ADE and preparation time (PT) in the mesial canals of the mandibular first permanent molars in different access cavity designs and the amount of sodium hypochlorite in the extruded debris using attenuated total reflection-Fourier transform infrared spectrometer (ATR-FTIR).

MATERIALS AND METHODS: Human mandibular first permanent molars (N = 72) were selected and randomly divided into six groups ( n = 12) based on type of cavity design and files used: Group 1, Conservative Access Cavity [ConsAC])-WaveOne Gold; Group 2, ConsAC-Mtwo; Group 3, ConsAC-XP-endo shaper; Group 4, Traditional Access Cavity [TradAC])-WaveOne; Group 5, TradAC-Mtwo; and Group 6, TradAC-XP-endo shaper. All the ConsAC were prepared with a customized template fabricated using cone beam computed tomography. ADE evaluation was done using the Myers and Montgomery set up. All the instruments were used according to the manufacturers' instructions, followed by a final irrigation using Endoactivator. The time taken for preparation was calculated using a digital watch. Five samples in each group was taken and subjected to ATR-FTIR analysis.

RESULTS: There was no significant difference between the groups with respect to ADE ( P > 0.05). Whereas, a statistically significant difference was seen in PT between the TradAC and ConsAC ( P < 0.05). Using ATR-FTIR, it was found that all the samples of extruded debris had the presence of sodium hypochlorite.

CONCLUSIONS: All instrumentation systems produced ADE irrespective of access cavity design. The time taken for preparation of canals in ConsAC was significantly longer compared to TradAC.

CLINICAL RELEVANCE: ADE can translate clinically as postoperative pain. Assessing the ADE in ConsAC could shed light on the type of file systems that can be used in such cavities in order to minimize postoperative pain clinically.