Assessment of the trabecular structure of the mandibular condyle in temporomandibular disorders using fractal analysis: A systematic review

Temporomandibular disorders (TMD) are frequently associated with early microstructural alterations in the trabecular architecture of the mandibular condyle that may precede overt morphological changes. Fractal analysis (FA) has emerged as a quantitative imaging-based method for assessing complex trabecular bone patterns and has been increasingly applied in dental radiology for the evaluation of subchondral bone quality. The present systematic review aimed to critically appraise the current clinical evidence regarding the diagnostic value of FA in detecting condylar trabecular alterations in systemically healthy adult individuals with TMD. A comprehensive literature search was conducted in PubMed, Scopus, Web of Science, and national databases up to September 15, 2025. Clinical studies evaluating fractal dimension (FD) values of the mandibular condyle in TMD patients and healthy controls were included. Nine clinical studies met the eligibility criteria. The majority of included studies reported significantly lower FD values in TMD or degenerative joint disease groups compared with healthy controls, indicating reduced trabecular complexity and potential early bone deterioration. However, substantial methodological heterogeneity was observed regarding imaging modality, voxel size, region of interest selection, and FA algorithms, which limited direct comparability of FD values across studies. Overall, FA appears to be a promising noninvasive adjunctive imaging tool for detecting early condylar microstructural changes in TMD; nevertheless, standardized imaging protocols and well-designed multicenter studies with larger sample sizes are required to confirm its diagnostic and prognostic utility.