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.
Anterior teeth may have aberrant anatomical variations in the number of roots and root canals. A review of the literature was conducted using appropriate key words in major endodontic journals to identify the available reported cases as well as experimental and clinical investigations on accessory roots and root canals in anterior teeth. After retrieving the full text of related articles, cross-citations were identified, and the pooled data were then discussed. Results revealed a higher prevalence in accessory root/root canal variations in mandibular anterior teeth than in maxillary counterparts. However, maxillary incisor teeth revealed the highest tendency for accessory root/root canal aberrations caused by anomalies such as dens invaginatus and palato-gingival groove. Primary anterior teeth may also exhibit external and internal anatomical variations in the root, especially maxillary canines. Therefore, dental practitioners should thoroughly assess all teeth scheduled for root canal treatment to prevent the undesirable consequences caused by inadequate debridement of accessory configurations of the root canal system.
The study consisted of analysis of all cases of anomalies in the primary dentition that were seen or treated by the authors in the Department of Children's Dentistry and Orthodontics. A total of 79 occurrences of anomalies was seen in 65 children. The anomalies detected were double teeth, hypodontia and supernumerary teeth. Radiographic examinations of the affected children showed that over 60% of the cases with anomalies in the primary dentition are associated with anomalies of the succadeneous permanent dentition. All subjects with hypodontia of the primary dentition presented with hypodontia of the permanent dentition. However, anomalies of the permanent dentition were seen in 59% of subjects with primary double tooth and 50% of subjects with primary supernumerary tooth.
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.