Dental age estimation: periodontal ligament visibility (PLV)-pattern recognition of a conclusive mandibular maturity marker related to the lower left third molar at the 18-year threshold.

The purpose of this study was to explore the applicability of periodontal ligament visibility (PLV) at the 18-year threshold. This mandibular maturity marker is graded into four separate age related stages, PLV-A, PLV-B, PLV-C, and PLV-D. These are discernible on a dental panoramic tomograph (DPT). The sample comprised a total of 2000 DPTs evenly divided into half yearly age bands from 16.00 to 25.99 years with 50 females and 50 males in each age band. It was found that PLV-A and PLV-B had minimum values below the 18-year threshold. PLV-C and PLV-D in females had minimum values of 18.08 and 18.58 years, respectively. In males, the minimum values for PLV-C was 18.10 years and PLV-D was 18.67 years. It was concluded that the presence of PLV-C or PLV-D indicates that a subject is over 18 years with a very high level of probability.