Orolabial Melanosis: Principles of Formulating a Clinical Diagnosis

The group of melanotic lesions (ML) of the orolabial region is extremely diverse, creating objective difficulties in differential diagnosis. To perform a comprehensive differential diagnostic evaluation and to plan treatment strategies, it is advisable to supplement the clinical classification of ML with objective diagnostic criteria.

This retrospective, single-center study was designed according to the principles of clinical examination, including objective examination of the oral cavity, periodontal tissue assessment with evaluation of the Greene-Vermillion hygiene index, periodontal indices (papillomarginal-alveolar - PMA, SPITN), and assessment of the location, size, and staining intensity of ML using the authors' method, followed by statistical analysis. Conservative treatment of diseases of the oral mucosa and periodontium with subsequent dynamic observation was carried out for periods of 3 to 10 years. Statistical processing of the clinical data was performed using Microsoft Excel and the Statistica package, including calculation of the mean and standard error, Student's t-test, and analysis of variance with subsequent pairwise comparisons to determine the probability of error (p). Differences between means were considered statistically significant at P < 0.05.

A total of 318 cases of ML in the orolabial region were examined. The size of ML foci was found to increase significantly with the depth and extent of the inflammatory process in the periodontium. Depending on the disease form, the average length of lesions increased more markedly (P < 0.01) than the average width (P < 0.05). According to the authors' method for objective assessment of ML staining intensity in the oral mucosa and lips, comparison of staining intensity with the nosological forms of inflammatory periodontal diseases showed the following patient distribution: degree I in 82 patients (25.8%), degree II in 164 patients (51.6%), and degree III in 72 patients (22.6%). Statistically significant differences for ML degree I were identified between the first and second nosological forms of inflammatory periodontal diseases (P < 0.05). For ML degree II, significant differences were observed between the first and second, first and third, first and fourth, second and third, and second and fourth nosological forms (p < 0.05). Analysis of ML degree III also demonstrated a high level of statistically significant differences between the second and third, and second and fourth nosological forms (P < 0.01). For objective assessment of ML, clinical classification criteria and diagnostic principles were developed that reflect the characteristics of their course depending on the hygienic status of the oral cavity and periodontal tissues.

Unification of fundamental approaches to formulating a clinical diagnosis allows for differential diagnosis of ML, planning of treatment and preventive measures, and assessment of disease dynamics using objective criteria.