Multiple supernumerary teeth without any associated systemic conditions or syndromes are not common. The author reviewed most of the cases reported in the English-language literature from 1969 to the present. It was found that there was a predilection of non-syndrome multiple supernumerary teeth to occur in the mandible. When analyzed according to specific sites for both jaws, there was a predominance of the multiple supernumerary teeth to occur in the premolar area, followed by the molar and the anterior regions respectively. The mandibular premolar region had the highest frequency of occurrence for both jaws combined.
Transposition of teeth is a rare and special type of ectopic eruption where two contiguous teeth are found occupying each other's respective normal positions. Nine patients with transposed maxillary teeth are reported. The literature on transpositions, especially on the theories regarding the aetiology, is reviewed.
An investigation of the prevalence and distribution of hypodontia was carried out in Malaysian children between the ages of five to fifteen years. Hypodontia occurred in 2.8 per cent of these children. A greater number of females were found to have hypodontia, the ratio of affected females to males is 1.6:1. The teeth most frequently missing were the maxillary lateral incisors followed by the mandibular lateral incisors, then the mandibular second premolars. The aetiology of the condition is discussed. It is noteworthy that studies showing the lower second premolars to be most commonly missing have younger subjects. This suggests delayed development of these teeth in some individuals.
This study was conducted to determine the prevalence of pre-eruptive intracoronal dentin defects from panoramic radiographs from a group of children and young adults aged 20 years and below. The radiolucent lesions were noted with regard to which teeth were affected, the location of the defects and the size of the defects relative to the width of dentin. Out of 1007 radiographs examined, 275 (27.3%) have pre-eruptive dentin defects. The prevalence of anomaly among males was 28.4% as compared to 26.2% among females. However, the difference between genders was not significant, thus subsequent results have been combined. Of 275 subjects with dentin radiolucencies, 243 subjects (88.7%) had only one affected tooth, 30 subjects (10.9%) had two teeth affected and 2 subjects (0.7%) had three affected teeth. The tooth prevalence of the anomaly was 2.1% and most of the lesions occurred as a single occurrence on the affected tooth. Within each tooth type, the highest tooth prevalence of intracoronal dentin defect was found in the upper first premolar (5.1%). More than half of the lesions extended less than 1/3 of the width of the dentin thickness. The high prevalence of the condition indicates the need for increased awareness and recognition of this during radiographic examination of teeth in the pediatric age group in early pre-eruptive stages so that early detection and diagnosis can be made and treatment can be done at the most appropriate time.