Fractal and Morphometric Analysis of Mandibular Bone in Periodontitis

Periodontitis is a common inflammatory disease characterized by the destruction of tooth-supporting tissues, often caused by specific microorganisms. In addition to clinical evaluation, radiographic assessment of alveolar bone loss is essential for the diagnosis, treatment planning, and prognosis of periodontal diseases. Panoramic radiography is widely used in oral and maxillofacial imaging and can provide valuable information about cortical and trabecular bone structures through quantitative methods. Fractal analysis is a mathematical approach that measures the complexity and trabecular patterns of bone. It has been shown to be independent of projection geometry and is commonly applied in digital radiographs. The fractal dimension (FD) reflects the degree of trabecular complexity and can serve as a numerical indicator of bone microarchitecture. The box-counting method, as described by White and Rudolph, will be employed in this study using ImageJ software. In addition to fractal analysis, morphometric indices such as the mental index (MI) and panoramic mandibular index (PMI) will be calculated to assess mandibular cortical thickness and morphology. This retrospective observational study will include 120 panoramic radiographs obtained from the archives of the Department of Oral and Maxillofacial Radiology, Istanbul University Faculty of Dentistry. The study group will consist of patients with a confirmed diagnosis of periodontitis according to the 2017 classification by the European Federation of Periodontology and the American Academy of Periodontology, while the control group will include systemically healthy individuals with no periodontal disease. Exclusion criteria include individuals under 18 years of age, those with systemic or syndromic conditions, and radiographs with diagnostic errors. Radiographic measurements will be performed independently by two oral and maxillofacial radiologists, and intra- and inter-observer agreement will be tested through repeated evaluations. Statistical analyses will be conducted using NCSS 2007 software, applying descriptive statistics, Shapiro-Wilk test for normality, independent t-test or Mann-Whitney U test for group comparisons, and chi-square tests for categorical data, with a significance level of p\<0.05. The study is expected to reveal quantitative differences in mandibular bone structure between individuals with periodontitis and healthy controls. The results may contribute to improved diagnostic accuracy of panoramic radiographs in periodontal disease and provide additional tools for early detection and risk assessment in clinical practice.