Comparison of the incidence of individual malocclusions in children with physiological replacement of teeth and children with premature loss of deciduous molars who reported for orthodontic treatment

Introduction
Malocclusions and dental caries are classified as dental social diseases. Both intrinsic and extrinsic factors affect the formation of malocclusions.

Aim
The aim of the study was to compare the incidence of malocclusions in children with physiological replacement of teeth and children with premature loss of deciduous molars who reported for treatment to the Department of Orthodontics, Medical University of Warsaw.

Material and methods
Medical records (patient charts, models, X-rays) of 205 patients presenting for orthodontic treatment at the Department of Orthodontics, Medical University of Warsaw, between 2006 and 2016 were analysed. Eligibility criteria for the study included mixed dentition period and no history of previous orthodontic treatment. The patients’ age ranged from 7–11 years. Other selection criteria included the presence of all permanent tooth buds and the absence of congenital malformations. Group one (102 patients) included patients with premature loss of deciduous molars, and group two (103 subjects) included patients with physiological tooth replacement.

Results
The prevalence of individual malocclusions in the group one and two was as follows: posterior defects: 50.98% and 56.86%; transverse defects: 21.56% and 23.52%; vertical defects: 13.72% in each group; anterior defects 2.94% and 1.96%; dental abnormalities 95.1% and 86.27%, respectively.

Conclusions
Premature loss of deciduous molars results in dental abnormalities associated with tooth displacement in both dental arches and impaired time of eruption of permanent teeth. Dental abnormalities were more common in the study group compared to the control group and it was a statistically significant difference. The effect of premature loss of deciduous molars on malocclusions requires further studies.