Odontogenic myxoma of the mandible in a 5-year-old boy presenting with trismus: a case report

Key findings from this study

• The study found that odontogenic myxoma presented with chronic trismus as the primary symptom rather than painless swelling in this 5-year-old patient.
• The authors report that despite radiographically successful tumor removal and bone regeneration, mouth opening remained severely limited at 1-year follow-up.
• The researchers demonstrate that sacrifice of the inferior alveolar nerve during surgical management did not prevent persistent functional impairment.

Overview

Odontogenic myxoma is a rare benign odontogenic tumor with atypical presentation in young children. This case describes a 5-year-old boy with chronic trismus as the primary presenting symptom rather than the typical painless jaw swelling. Imaging revealed a multilocular radiolucent lesion in the left mandibular body and ramus with medial cortical perforation and proximity to the medial pterygoid muscle. Biopsy confirmed odontogenic myxoma diagnosis.

Methods and approach

Orthopantomogram and MRI imaging characterized the lesion morphology and anatomical relationships. Biopsy provided histopathological confirmation of odontogenic myxoma. Surgical treatment consisted of enucleation and curettage with preservation of mandibular structural continuity. The surgical approach sacrificed the inferior alveolar nerve to achieve adequate tumor removal. Follow-up assessment included radiographic evaluation of bone regeneration at 12 months and functional measurements of mouth opening.

Results

Radiographic examination demonstrated good bone regeneration at 1-year follow-up with no recurrence detected. However, mouth opening remained severely restricted despite 12 months of physiotherapy and jaw-stretching exercises. The persistent trismus represented a significant functional impairment independent of successful tumor removal. Sacrifice of the inferior alveolar nerve during surgical management did not prevent the sustained limitation in mandibular mobility.

Implications

Trismus in pediatric populations warrants consideration as a potential red-flag symptom for underlying malignancy or significant pathology. Progressive jaw-opening restriction in children should prompt prompt imaging evaluation and specialist assessment to exclude serious etiologies. The case demonstrates that anatomically successful tumor removal does not guarantee restoration of preoperative functional capacity, particularly when adjacent neuromuscular structures are involved.

Scope and limitations

This summary is based on the study abstract and available metadata. It does not include a full analysis of the complete paper, supplementary materials, or underlying datasets unless explicitly stated. Findings should be interpreted in the context of the original publication.