Epidemiology and Etiological Factors which Influence the Occurrence of Rare Cases of Double Teeth in Primary and Permanent Dentition and Presentation of Two Individual Clinical Cases

Dental anomalies appear as a result of disorders (partial or excessive development) which occur during different stages of tooth development. Among them, the following disorders can be distinguished: concerning anatomical structure (size and shape), position, structure of tissues and number of teeth. The occurrence of double teeth in primary dentition may precede dental abnormalities in permanent dentition. Fused as well as concrescent teeth are the cause of occlusion disorder. They can be the cause of protrusion and rotation of teeth. A fused permanent central incisor brings about the development of a diastema. Concrescent, fused or giant teeth in the maxilla can contribute to the occurrence of class III defect within the canines as well as tooth eruption outside the dental arch. Furthermore, dental anomalies might cause periodontal problems as well as more frequent occurrence of carries and difficulties in endodontic treatment, but above all they disturb the harmony of the dental arch. Therefore, a plan to orthodontically remodel the dental arch as an integral part of the complex treatment of patients with these types of dental anomalies is very important. The aim of the paper is the introduction of the current state of knowledge concerning the epidemiology and etiological factors which influence the development of dental abnormalities in primary and permanent dentition, with particular attention to double teeth, as well as the presentation of two individual clinical cases