Atypical Stafne bone defect: a systematic review

Atypically located Stafne bone defects (SBDs) may be challenging to identify because they deviate from the typical posterior mandibular presentation. This systematic review aims to analyze and synthesize the radiographic, anatomical, and histological characteristics of atypically located SBDs reported in the literature and to assist clinicians in orienting the diagnostic hypothesis.

A comprehensive literature search was conducted in the PubMed, Scopus, Embase, and Web of Science databases up to January 2026. Eligibility criteria included English-language case reports and case series describing atypically located Stafne bone defects (SBDs). Study selection, data extraction, and quality assessment were performed independently by two reviewers using an adapted assessment tool for case reports.

Seventy studies encompassing 91 atypical cases were included. Atypically located SBDs were most frequently reported in the anterior mandible. Despite their variable localization, these defects share key anatomical and radiographic features with classical SBDs, including well-defined unilocular radiolucencies and lingual cortical depressions. Advanced imaging modalities, particularly cone-beam computed tomography (CBCT) and magnetic resonance imaging (MRI), play an important role in confirming these features and in orienting the diagnostic hypothesis. Histological analysis, when available, most commonly revealed normal salivary gland tissue without evidence of neoplastic transformation.

Atypically located SBDs demonstrate consistent radiographic and anatomical characteristics that may assist clinicians in orienting the diagnostic hypothesis. This review improves the understanding of this under-recognized anatomical variant and highlights the importance of appropriate imaging evaluation in ambiguous cases.

Recognition of these features may facilitate accurate diagnosis and help avoid unnecessary invasive procedures.