Age-related changes of fibroblast density in the human periodontal ligament

OBJECTIVE: Recently, research has focused intensely on age-related tissue changes, not only in the field of dermatology but also in dental sciences. Although many new insights into age-related morphological, ultrastructural and biochemical changes in the periodontal ligament tissue have been gained, the basic question of whether there is a quantitative change in cell number remains unanswered or, at least to date, unpublished. Thus, the aim of this study was to detect age-related changes of the periodontal ligament regarding fibroblast density. MATERIAL AND METHODS: 33 lateral tooth-bearing segments of the maxilla were obtained from deceased human individuals of different age, ranging from 7 to 63 years. The buccal segment of the periodontal ligament of the mesiobuccal root of the first maxillary molar was evaluated histomorphometrically to obtain the fibroblast density. RESULTS: The results clearly indicate a steady and statistically significant decline of fibroblast number with age. CONCLUSION: It may be concluded that fibroblast density in the physiological human periodontal ligament tissue decreases with age, thus causing an initial delay in physiological, pathological or externally induced processes that require remodeling of the periodontal ligament, e.g. traumatic occlusion or orthodontic tooth movement. It may be assumed that an orthodontic tooth movement in elderly patients requires more time in the initial treatment phase and should be done with lighter forces.