Clinical Analysis And Research Of 60 Patients With Congenitally Missing Teeth

Objective:The purpose of this research is to explore clinical characters and application of congential oligodontia by analysing the number, distribution, type, malocclusion and treatment methods of patients with congenitally missing teeth.Methods:580 orthodontic patients were selected from 2011.9 to 2014.3 in Oral Hospital of Shanxi Medical University,They were all between 12~20 years old,the average age was16.5.The research was executed according to the clinical data including oral examination,radiographs and model.1.To analyse statistically the number, position, type of congential oligodontia.2. To analyse the clinical manifestation and the relationship between constituent ratio of distribution of missing teeth with different type of malocclusion.3.To make plans according to the result and evaluate the curative effect of treatment results.Results:1.60 cases with congenitally missing teeth were found among the 580 orthodontic patients, accounting for 10.34%,Missing a total of 127 teeth. The number of missing mandibular second premolar was 36(28.34%).mandibular central incisors 24(18.9%)and mandibular first molars only 2, none of missing second molar and canine teeth. there was no signifcant difference in the number of missing teeth between left andright(χ2=0.42, P >0.05).The lower mandible had higher percentage of missing teeth(χ2=12.96,P <0.05), Most of the patients missed 1~2 teeth, 26 cases of 1 teeth missing(43.33%), 21 cases of 2 teeth missing(35%), the oligodontia were 5 cases(8.33%),There were significant differences among the type and constituent ratio of distribution( χ2==17.691, p<0.001), but no signifcant difference between females and males(χ2=0.00083,P>0.05).2. 19,27 and 14 cases were with Angle class I, II and III malocclusion respectively,There was statistically significance among constituent ratio of distribution of missing teeth and different type of malocclusion(Fisher exact value =20.161, p<0.05), 29 cases exsit deep overbite and deep overjet. Bolton index of 39 patients were unmatched.35 case were Mild to moderate crowding on the other dentition, Midline deviation were found in 29 patients.3. 11 cases were treated by orthodontic space closure,26 patients were extractions, 23 patients received regained space and prosthetic treatments, All the treatments were successful.The treatment time was among 10 to 27 months, the average duration was 20.2months.Conclusion:1.60 cases with congenitally missing teeth were found among the 580 orthodontic patients, accounting for 10.34%,The mandibular second premolar was the most vulnerable missing teeth.followed by the mandibular lateral incisor and maxillary lateral incisor. Most of the patients missed 1~2 teeth, The left and right were with similar numuber missing teeth,but the lower mandible had higher percentage of missing teeth,there was no signifcant difference between females and males.2.patiens usually showed different malocclusion types, as unmatched Bolton ratio,overjet,overbite as so on.3.There is not one method better than the other,and orthodontists should based on the correct analysis of the type of missing teeth,Bolton index, malocclusion type, development of alveolar bone and facial profile to make the best plan for patients with congenitally missing teeth.