Agenesis of second premolars and delayed dental maturation

The purpose of this work was to examine the relationship between second-premolar agenesis and how rapidly permanent dentition develops.

Panoramic radiographs of 678 girls and boys aged 6-14 years were evaluated. Subjects with syndromes or history of tooth extraction were excluded. The permanent dentition's stages of mineralization (scale 1-10) and eruption (1-7), and the resorption (1-5) of deciduous teeth were assessed.

Adjusted for age and sex, subjects with one or more missing second premolars revealed earlier developmental stages (mineralization: average -0.37 stages per tooth, 95% CI -0.23 to -0.50; eruption: -0.42, 95% CI -0.60 to -0.24; resorption: -0.36, 95% CI -0.49 to -0.24; all p < 0. 001). Canines, premolars, and second molars were particularly affected, regardless of their location in the same or opposing jaw, and independent of the number of missing teeth. Overall dental development was delayed by 8.6 months (95% CI 5.4-11.8) in subjects with missing second premolars.

These results have implications for several areas of medicine. Joint biological etiology for the agenesis and late maturation of permanent teeth should be considered in developmental research. Orthodontists should be aware of the delay associated with missing second premolars when timing interventions. Forensic age assessment based on tooth development should adjust for missing teeth to avoid underestimating the subject's age.