Comparative Effect of Minimally Invasive Endodontic Access Cavity Designs on Fracture Resistance and Root Canal Treatment Outcomes
DOI:
https://doi.org/10.68041/jdosr.v1i1/04Keywords:
Dentin, Endodontics, Postoperative Pain, Root Canal Obturation, Root Canal Preparation, Tooth FracturesAbstract
Background: Minimally invasive designs seek to maintain pericervical dentin and can improve the resistance of root-filled teeth. This study aimed to compare the fracture resistance and outcomes of conventional, conservative and ninja endodontic access cavity designs. Methods: 120 single-rooted teeth were allocated to three pre-defined groups (n=40 each): conventional, conservative, and ninja endodontic access cavity. Standardized access preparation, instrumentation, irrigation, and obturation were carried out. The fracture resistance was tested on a testing machine. Canal location, the working length achieved, quality of obturation, procedural errors, postoperative pain, treatment time, canal curvature, and remaining dentin thickness were evaluated. All data were analyzed using SPSS version 26.0, where p<0.05 was considered statistically significant. Results: There was a significant difference in fracture resistance between the groups (p<0.001), with the lowest resistance in the conventional access group (742.6 ± 118.4 N), followed by the conservative access group (861.3 ± 126.7 N) and the ninja endodontic access cavity (918.7 ± 134.2 N). Canal location, working length, obturation quality, and procedural errors were not significantly different. Postoperative pain was lower at 24 hours (p=0.018) and 72 hours (p=0.041) in the minimally invasive groups, and the duration of treatment was also shorter (p=0.006). The remaining dentin thickness was positively associated with fracture resistance (p<0.001), while canal curvature had a negative association (p=0.008). Conclusion: Conservative and ninja endodontic access cavities were associated with better fracture resistance without compromising treatment outcomes. Longer-term studies are needed to determine their effects on tooth survival and periapical healing.
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