(1) Background: Tooth agenesis is one of the most common developmental dental anomalies often affecting the maxillary incisors area and premolar regions. (2) Purpose: The aim of this study was to assess the prevalence and distribution of permanent tooth agenesis and the associated dental abnormalities among orthodontically treated children. (3) Materials and Methods: This study was carried out utilizing 3000 pretreatment records of children who underwent orthodontic treatment, 1780 (59%) females and 1220 (41%) males, aged 10–25 years (mean age 15 years). Tooth agenesis and other dental anomalies were surveyed using their panoramic radiographs, according to gender, pattern, and location. The level of statistical significance was set at p < 0.05 using t-test or Chi-Square tests. (4) Results: The total number of missing teeth, excluding third molars, was 518 (17%) found in 326 (11%) children. The majority were the maxillary lateral incisors, which was 176 teeth (34%) (p < 0.05). Of them, 111 (63%) were in females, and 65 (37%) were in males. The second most common missing tooth was mandibular second premolars, which was 137 teeth (26%), followed by missing 73 (14%) maxillary second premolars. Impacted teeth had the highest associated dental anomaly prevalence (14.3%), while transposition showed the lowest anomaly prevalence (0.5%). (5) Conclusions: A prevalence of 11% for tooth agenesis was detected in this study. More teeth were missing in the maxilla compare with the mandible. A significant association was found between missing maxillary lateral incisors and missing premolars (p < 0.05). Associated dental anomalies included an increased number of peg-shaped maxillary lateral incisors, palatally displaced and impacted maxillary canines, ectopic teeth, and infra-occluded (submerged) primary second molars.

(1) Background: tooth agenesis is a very common dental anomaly of the human dentition most often affecting the maxillary anterior region, mandibular and maxillary premolar regions. (2) Purpose: the present study was aimed to evaluate the prevalence and patterns between bilateral and unilateral tooth agenesis among orthodontic individuals and to illustrate the treatment options for missing teeth and the outcome. (3) Materials and methods: Pre-treatment records, photographs and radiographs, of 3000 consecutively treated orthodontic individuals from the post-graduate clinic of Tel Aviv University were surveyed to detect permanent tooth agenesis in either dental arch. The data was recorded according to gender, and location and quantified between unilateral and bilateral agenesis. Descriptive and comparative statistical analysis were performed with t-test and Chi-square test (p < 0.05). (4) Results: permanent teeth agenesis, excluding third molars, was found in 326 individuals (11%), 139 males (43%) and 187 females (57%). Of them, 59% were missing in the maxilla and (41%) were missing in the mandible. A higher prevalence rate of bilateral missing lateral incisors in the maxilla (62 cases), followed by bilateral missing second premolars in the mandible (44 cases) compared with unilateral missing teeth. (5) Conclusions: this study found an overall prevalence of missing permanent teeth in orthodontic patients to be 11%. The female: male prevalence ratio was roughly 3:2, with a greater tendency in the maxilla than in the mandible. A higher prevalence of bilateral missing maxillary lateral incisors and mandibular second premolar than unilateral missing teeth.

(1) Introduction: Mandibular second molar (MM2) impaction is a relatively rare dental anomaly, but its early detection is imperative for orthodontic diagnosis and treatment. This study evaluates early radiographic characteristics of MM2 in the process of its impaction and the role of the third molar (MM3) in this process. (2) Materials and Methods: Panoramic radiographs of orthodontic patients of Chinese-American origin (n = 5575), age 9–15 years (mean 13.13) were examined for MM2 impactions and the presence of MM3. (3) Results: A total of 151 patients with 212 impacted MM2s were detected in the Chinese-American study group. Unilateral impactions were found more than bilateral and were distributed equally between the left and right sides. Mesial angulation of the impacted teeth was present in 92.7% of the cases, and MM3s were found adjacent to the impacted MM2s in 97.4% of the cases. (4) Conclusions: MM2 differential root developments with deficient mesial root lengths appeared to be the primary cause for MM2 impaction. Posterior crowding and arch length deficiency were contributing factors causing MM2 impaction. This impaction occurred early, before the third molar bud was developed. It sometimes occurred even when the third molar was congenitally missing. Nevertheless, the possible involvement of the third molar in MM2 impaction needs further investigation.

The aim of this study was to determine the prevalence of dental anomalies and whethera significant association exists between dental anomalies and consanguinity marriage among Arabic orthodontic patients in Israel. Pretreatment panoramic radiographs of 513 patients (38% males and 62% females) were examined to detect dental anomalies related to number, size, shape, and eruption. A chi-square test was carried out to determine the associations between dental anomalies, gender, and consanguinity marriage. The results indicated that 29% of the subjects manifested at least one dental anomaly. Impacted tooth was found to be the most frequent dental anomaly, with a prevalence of 13.5%, whereas fusion and transmigration were found to be the least common, with a prevalence of 0.2% each. The prevalence of dental anomalies was significantly greater in males (p < 0.001) than in females. In our sample a significant association was found between dental anomalies and consanguinity marriage, and it was found to be greater in subjects with a family history of consanguinity marriage. This association can be attributed to the negative effects of consanguinity marriage, which was also reported in many studies in other fields. This study suggests that consanguinity marriage can be one of the factors involved in the development of dental anomalies in certain at-risk populations.