Aim: External cervical resorption is a form of root resorption which begins in the cervical region of the tooth and spreads out in the thickness of the dentin in an irregular way; clinically, it may be not visible and, as it is generally asymptomatic before involvement of the pulp, it is often an occasional finding in radiographic examination. Several factors are related to its aetiology. This paper reports a case of external cervical resorption in a mandibular right first molar of a 17-year-old patient; the tooth was extracted and histological analysis was performed.
Materials and methods: Radiographic examination showed a progressive external cervical resorption of the lower right first molar; extension of the lesion and pulp involvement indicated tooth extraction; the sample underwent histological analysis.
Results: The histological study confirmed the presence of vascular connective tissue in the resorptive lacunae, invading the dentin from the external surface of the root, and perforations from the defect into the pulp; it was also noticed the presence of bone-like tissue.