To study the molecular pathogenesis of aggressive periodontitis and supernumerary premolar in a Thai patient affected with amelogenesis imperfecta, hypoplastic type, follicular hamartomas, gingival hyperplasia, and unerupted teeth.
Methods:
Clinical and radiographic examinations and mutation analysis of FAM20A was performed in the 13-year-old Thai patient and his non-consanguineous parents. The initial oral examination was done when the patient was 10 months old.
Results:
Clinical examination revealed amelogenesis imperfecta, hypoplastic type, prolonged retention of primary teeth, and generalized gingival hyperplasia. Severe periodontitis of all first molars and second premolars was observed. Radiographic examination showed multiple unerupted permanent teeth with large dental follicles, root dilaceration of unerupted molars, and calcified mass in pulp chambers. Severe alveolar bone loss was observed around all first molars and second premolars. Mutation analysis of FAM20A revealed compound heterozygous mutations c.349_367delCTGGCCAGCCAGGAGGCGC and c.915_918delCTTT. These deletions are predicted to result in frameshift and premature termination of translation.
Conclusions:
In addition to amelogenesis imperfecta, hypoplastic type, follicular hamartomas, unerupted teeth, and gingival hyperplasia, mutations in FAM20A have demonstrated to cause aggressive periodontitis and supernumerary premolar. It is encouraged to do mutation screening of FAM20A gene in patients affected with isolated aggressive periodontitis.