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Twinning is an anomaly in which one tooth has combined with another or enlarged itself to the point of doubling its substance. A discussion of the nomenclature and a report of bilateral twinning are presented. A possible cause of the twinning events in this case include gemination of the maxillary right and mandibular left canines and fusion of the maxillary left and mandibular right canines with supernumerary teeth.
Oral-facial-digital syndrome is a group of congenital anomalies, which affects the face, oral structures and digits. There are nine subtypes. OFDS type I, is x-linked dominant trait mostly affecting females. Reports of OFDS type 1 in Asians are extremely rare. This paper shows a case of OFDS type 1, in a southern Chinese girl, who in addition to most of the classic features, had fusion of the mandibular canine and lateral incisor teeth.
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Radiographs play an important role in assessment of both the location and the typing of supernumerary teeth. In general, periapical, occlusal, and/or panoramic radiographs are sufficient for providing the information required by the clinician. These modalities, however, do not provide detailed information concerning the 3-dimensional relationship between supernumerary or ectopically impacted teeth and adjacent structures. This case report discusses the value of computerized tomography (CT) for evaluation of the root relationships of supernumerary teeth located palatally to maxillary permanent central incisors. CT accurately demonstrated the relationship between the supernumerary teeth and the permanent tooth roots.
Six cases of asymptomatic dental twinning anomalies in the primary dentition are reported in 4205 school children. A clinical and radiographic presentation of the cases of fusion of primary incisor teeth is illustrated. This clinical entity has been found to appear with varied clinical and radiographic appearances. An association of fusion of primary incisors with the number of succedaneous teeth was seen.
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The objective of this study was to review the literature with respect to the root and canal systems in the maxillary first molar. Root anatomy studies were divided into laboratory studies (in vitro), clinical root canal system anatomy studies (in vivo) and clinical case reports of anomalies. Over 95% (95.9%) of maxillary first molars had three roots and 3.9% had two roots. The incidence of fusion of any two or three roots was approximately 5.2%. Conical and C-shaped roots and canals were rarely found (0.12%). This review contained the most data on the canal morphology of the mesiobuccal root with a total of 8399 teeth from 34 studies. The incidence of two canals in the mesiobuccal root was 56.8% and of one canal was 43.1% in a weighted average of all reported studies. The incidence of two canals in the mesiobuccal root was higher in laboratory studies (60.5%) compared to clinical studies (54.7%). Less variation was found in the distobuccal and palatal roots and the results were reported from fourteen studies consisting of 2576 teeth. One canal was found in the distobuccal root in 98.3% of teeth whereas the palatal root had one canal in over 99% of the teeth studied.
A 'double' tooth is an uncommon dental developmental anomaly that can occur in the deciduous and/or permanent dentition. It is not always possible to differentiate clinically between fusion and gemination. Clinical and radiographic examination, as well as a histological assessment, can help to differentiate between fusion and gemination. A case of fusion in the deciduous dentition is presented to demonstrate the diagnostic differences but also, more importantly, to draw attention to the potential impact of 'double' teeth on the developing secondary dentition and its future management.
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Hypodontia has been observed as one of the most common human dental developmental anomalies. It may be defined as agenesis of one or more teeth. The prevalence in the permanent lower central and lateral incisor region is low, ranging from 0.23 percent to 0.08 percent, respectively. This is compared with an overall incidence of hypodontia of 3.49 percent. However, significant racial variation occurs. Treatment options generally available are: no treatment, closure of spaces orthodontically, or prosthetic replacement. Aetiology, associated anomalies, and factors involved in treatment choice are discussed. A report of four cases of hypodontia of the permanent lower anterior teeth and their orthodontic management is presented.
The discovery of a rare combination of fusion and gemination in one clinical crown, involving the same primary teeth in two patients, within a short period of time, is described.
Abnormalities in number of teeth are occasionally noted in clinical cases. Many theories have been proposed as regards the causes of the occurrence of supernumerary teeth, including atavism theory, mechanical tooth germ separation theory, tissue induction theory, and dental laminar morphological disturbance theory. However, none of these theories alone offers a sufficient explanation for this phenomenon. The incidence of supernumerary permanent teeth is approximately 1-3%. These are the maxillary anterior teeth, the maxillary molars, and the maxillo-mandibular premolars in terms of descending order of site of occurrence. On the other hand, incidence in the mandibular anterior tooth area, of which there have been few detailed reports, is about 0.01%, a markedly low value. In this paper, we report two rare cases of supernumerary teeth in the mandibular incisor area. We discuss their etiology and orthodontic treatment, and detail a differential diagnosis between the normal and supernumerary teeth. We found that it was difficult to establish a clear etiology and differentiation between the normal and supernumerary teeth.
The present report gives prevalence values for a selected group of developmental dental anomalies in 2393 Saudi children aged 4-12 yr from Gizan region, Saudi Arabia. The anomalies selected in this study were those involving the number and shape of the dentition. The following anomalies were identified: congenitally missing teeth (2.2%), supernumerary teeth (0.50%), gemination (0.08%), and peg-shaped lateral incisors (0.37%).
The aetiological factors related to many dental anomalies are still uncertain. Clinical descriptive terms may be useful in communications. This paper describes a previously unreported case of dental anomaly exhibited as bilateral double teeth associated with a talon cusp. The clinical variants related to crown numbers and forms are also discussed.
Regional odontodysplasia is a rare development anomaly affecting the teeth with an unknown etiology. This dental abnormality involves the hard tissues of the teeth that are derived from both epithelial (enamel) and mesenchymal (dentine & cementum) components of the tooth forming apparatus. Teeth in a region or quadrant of maxilla or mandible are affected to the extent that they exhibit short roots, wide open apical foramen and large pulp chamber, the thinness and poor mineralisation qualities of th enamel and dentine layers have given rise to a faint radiolucent image, hence the term "Ghost teeth". Both the permanent teeth and the deciduous teeth are affected. Females are more commonly affected than males. There is a maxillary predominance (2.5:1) with a predilection for the anterior teeth. Eruption of the affected teeth is delayed or does not occur. Because of the poor quality of the affected teeth, they cannot be rehabilitated for functional use therefore the treatment of choice is extraction with prosthetic replacement. However, necrosis and facial cellulitis appear to be a complication if these teeth are retained. A unique case of regional odontodysplasia affecting the entire right quadrant of mandible is reported here.
The form of primary and permanent teeth can differ morphologically from that which is considered normal, completely or in some parts. The changes in tooth form can be hereditary or caused by some disease or trauma. Fusion is a union of one or more teeth during development. Gemination means that two separate morphological units were created by division of the tooth germ. The intention of this study was to state the prevalence of double teeth (fusion and gemination) among the persons tested, as to gender, distribution in the maxilla or mandible, and whether the anomaly occurred bilaterally or unilaterally. The results of this investigation have shown that in a total of examined 3,517 plaster models, a prevalence of double teeth was 0.2%. 57.2% of them were fusioned and 42.9% geminated.