Dentoalveolar manifestations as the presenting sign of Gardner syndrome

Background

Gardner syndrome (GS) is a rare variant of familial adenomatous polyposis (FAP) associated with highly penetrant mutations involving the adenomatous polyposis coli (APC) tumor suppressor gene. Although GS is typically inherited as an autosomal dominant trait, approximately 30% of cases may represent de novo mutations. GS is classically characterized by multiple premalignant gastrointestinal polyps, osteomas, epidermoid cysts, and both cutaneous and subcutaneous soft tissue tumors. However, in correlation with the specific position of the mutations within the APC gene, GS demonstrates variable clinical expressivity. Between 22% and 30% of patients with GS present with dental abnormalities consisting of multiple impacted teeth, supernumerary teeth, and odontomas. These dental abnormalities may precede the intestinal manifestations and may serve as a key feature in early diagnosis of this syndrome.

Case Summary

A 14-year-old, otherwise healthy and asymptomatic, female patient presented to the orthodontic clinic with complaint of over-retained primary teeth. Clinical and radiographic evaluation revealed multiple impacted permanent teeth, micro-odontomas, and areas of sclerotic dense bone without significant facial deformity. On further inquiry, no familial pattern is identified within the patient’s immediate family. Subsequent medical and imaging workup led to identification of multiple adenomatous and tubular gastrointestinal polyps and a paraspinal desmoid fibromatosis. Further genetic studies confirmed a diagnosis of GS.

Conclusion

This case highlights the significance of recognition of the dentoalveolar manifestations in the early diagnosis of GS emphasizing on the importance of interdisciplinary collaboration and maintaining open communication with other healthcare practitioners. Dental clinicians may serve a key role in the early diagnosis and instigation of adequate treatment of this life-threatening rare syndrome.