Hypodontia and Supernumerary Teeth in a German Cleft Lip (with/without) Palate Population

Aim: The aim of this study was to evaluate the prevalence of hypodontia and supernumerary teeth in an exemplary German cleft lip (with/without) palate (CL/P) population dependent on cleft type and severity. Methods and material: Radiographs and dental records of cleft patients who had been treated and followed up in the Department of Oral and Maxillofacial Surgery, University Hospital Carl Gustav Carus Campus, Dresden, Germany (Jan 1994-Nov 2016) were evaluated concerning hypodontia and supernumerary teeth dependent on cleft type and severity of the cleft. Of 386 records, 108 patients met the inclusion criteria: non-syndromic cleft of the alveolus with/without palate, at least one clear panoramic x-ray, sufficient dental records. Statistical analysis was performed using x-square and binominal tests (p≤0.05). Results: Fifty-four individuals (50%) showed hypodontia and thirty-six (33.3%) supernumerary teeth. A total of 102 teeth were missing, of which 86 were missing in the upper and 16 in the lower jaw. Supernumerary teeth were exclusively present in the upper jaw, counting 43 teeth. Hypodontia occurred with a frequency of 70.6% in bilateral clefts and 46.2% in unilateral clefts, whereas supernumerary teeth were more frequent in unilateral clefts (36.3% vs. 4.2%). The cleft side was most often affected by both anomalies (cleft vs. non-cleft side: hypodontia - 63% vs.18.5%; supernumerary teeth - 83.8% vs. 13.5%). Conclusion: Cleft patients have a significant risk for hypodontia and supernumerary teeth, which are more common on the cleft side. Clear associations with cleft type and severity of the cleft could be detected. Keywords: hypodontia, supernumerary teeth, dental anomaly, cleft lip and palate, cleft lip and alveolus