Evaluation of failed endodontically treated molar teeth using micro-computed tomography

Area of Science:

• Endodontics
• Dental Imaging
• Morphology

Background:

• Assessing internal root canal morphology and obturation quality in failed endodontic treatments is crucial.
• First molars are frequently treated endodontically and can present complex root anatomy.

Purpose of the Study:

• To evaluate root canal morphology and obturation quality in failed endodontic treatments of first molars.
• To identify factors contributing to endodontic treatment failure using micro-computed tomography (micro-CT).

Main Methods:

• Micro-computed tomography (micro-CT) was used to examine 43 mesial roots of extracted first molars with failed endodontic treatment.
• Evaluated root canal filling quality, canal and isthmus configurations, presence of missed canals, and filling length.
• Compared void percentages in apical and coronal regions using an independent samples t-test (p < 0.05).

Main Results:

• An untreated second mesiobuccal canal was found in 70.6% of maxillary first molars.
• A middle mesial canal was detected in 50.0% of mandibular first molars.
• Higher void percentages were observed in apical (15.3%) versus coronal (7.3%) regions (p < 0.05); short fillings were common (57.7% mandibular, 35.3% maxillary).

Conclusions:

• Poor root canal filling quality and untreated extra canals are associated with endodontic treatment failure in first molars.
• Micro-CT imaging effectively revealed complex root canal anatomy and obturation defects.
• Addressing complex anatomy and ensuring complete obturation are key for successful endodontic outcomes.