[Statistical studies on numerical anomalies of teeth in children using orthopantomograms. Hyperdontia]

Statistical studies on numerical anomalies of teeth using orthopanthomograms had been attempted. In this paper, hyperdontia had been researched using 4009 orthopanthomograms of pedodontic patients. The tested were following: Male: Age 2-5 1036, 6-11 905, 12-22 Total 1963 Female: Age 2-5 1032, 6-11 985, 12-29 Total 2046 respectively. And 119 hyperdontia cases (143 teeth -1 tooth: 95 cases, 2 teeth: 24 cases) were found. Male: 84 cases 104 teeth (1 tooth: 64 cases, 2 teeth: 20 cases) Female: 35 cases 39 teeth (1 tooth: 31 cases, 2 teeth: 4 cases). Form supplemental teeth (normal form) deciduous teeth 4 teeth (4 anteriors containing 2-3 C in a case.) permanent teeth 32 teeth (anteriors: 28, premolars: 4) supernumerary teeth (abnormal form) deciduous cuspid like, conical 97 teeth (upper incisors) queer form 10 teeth (upper anteriors) Eruption line normal 85 teeth inversive 46 teeth horizontal 12 teeth Depth in alveolus Hyperdontia are classified in following: 1. in the alveolus deeper than permanent dentition in deciduous teeth period type I 1.7% in permanent teeth period type I' 23.5% 2. in the same depth of permanent dentition in deciduous teeth period type II 24.4% in permanent teeth period type V 9.2% 3. in the depth between permanent dentition and deciduous dentition type III 38.7% 4. in the deciduous dentition type IV 3.4% Type I, Type I', and Type III (total 63.9%) possibly belong to different teeth generation from deciduous and permanent teeth.