Association between teeth agenesis and Angle's classes in an Italian population

Area of Science:

• Dental Science
• Orthodontics
• Genetics

Background:

• Teeth agenesis, or hypodontia, is the developmental absence of one or more teeth.
• Prevalence ranges from 2.7% to 11.3%, with multifactorial causes including genetics, environment, and trauma.
• This study investigates tooth agenesis prevalence in orthodontic patients with different Angle malocclusions.

Purpose of the Study:

• To determine the prevalence of tooth agenesis in a sample of orthodontic patients.
• To analyze the distribution of tooth agenesis across different Angle malocclusion classes.
• To identify the most commonly missing teeth in patients with tooth agenesis.

Main Methods:

• Analysis of 900 non-syndromic patients without prior orthodontic treatment or extractions.
• Data collection included clinical examinations, dental records, photographs, study casts, and radiographic imaging.
• Patients were categorized into four groups based on Angle malocclusion and presence of dental agenesis.

Main Results:

• The overall prevalence of tooth agenesis in the sample was 8.80%.
• Class II/2 malocclusion showed the highest prevalence (20.37%), followed by Class III (11.19%), Class II/1 (8.05%), and Class I (6.62%).
• A statistically significant difference in agenesis distribution was observed among malocclusion groups (P=0.0059).

Conclusions:

• Tooth agenesis prevalence significantly differs across malocclusion types, with Class II/2 being the most affected.
• The most frequently absent teeth are mandibular second premolars (32.40%), maxillary lateral incisors (27.70%), and maxillary second premolars (15.50%).
• Findings highlight the association between specific malocclusions and patterns of tooth agenesis.