# Dens Invaginatus—Mandibular Second Molar—Case Report

## TL;DR

This case report describes the successful endodontic treatment of a rare tooth anomaly in a mandibular second molar.

## Contribution

The paper presents a detailed clinical approach to managing a type IIIb dens invaginatus in an unusual location.

## Key findings

- The patient showed no symptoms during and after treatment.
- Radiographs confirmed healing of the periapical lesion over 9 months.
- CBCT was essential for accurate diagnosis and treatment planning.

## Abstract

Background: Dens invaginatus is a rare developmental tooth anomaly that can occur in permanent, primary, and supernumerary teeth, with a tendency to affect the maxillary second incisors. It develops during odontogenesis due to the invagination of the enamel organ into the dental papilla. Methods: This study describes the endodontic management of a 24-year-old patient with a type IIIb invaginated tooth in the mandibular second molar. Clinical examination revealed no response to thermal and electrical stimuli, no response to vertical and horizontal percussion, and no pathological mobility. The depth of the gingival pocket was 8 mm. Root canal therapy was performed over three sessions. The patient remained asymptomatic during the treatment and follow-up visits. Results: Radiographs at 4-, 6-, and 9-month post-treatment showed healing of the periapical lesion. Conclusions: Due to the complex canal anatomy of invaginated teeth, confirming the diagnosis with cone-beam computed tomography (CBCT) is essential. Treating invaginated teeth presents significant challenges for clinicians, requiring a thorough understanding of the dental anatomical variability, advanced manual skills, and the use of specialized equipment.