AGE ASSESSMENT OF THE DYNAMICS OF MORPHOLOGICAL REARRANGEMENT OF BONE TISSUE OF THE ARTICULAR PROCESSES OF THE HUMAN LOWER JAW DEPENDING ON THE LOSS OF THE MASTICATORY TEETH.

OBJECTIVE: Aim: To analyze morphometric changes in the structure of bone tissue of the mandibular articular processes and establish their densitometric dependence on the masticatory teeth loss in people of I-II periods of adulthood. PATIENTS AND METHODS: Materials and methods: We analyzed 136 digital CT recordings of human temporomandibular joints. The research subjects were divided into three groups based on the degree of dentition defect acquisition: the first - a limited defect, the second - a final defect, and the third - a preserved dentition (control); by age into two periods of adulthood of postnatal human ontogenesis. Digital statistical analysis of the bone density is presented as M±σ (mean and standard deviation). We compared the experimental groups with the control group using nonparametric statistical analysis. RESULTS: Results: Changes in the vertical dimension of occlusion due to limited masticatory teeth loss acquire variable morphometric features, causing an interrelated process of bone atrophy of the cellular part and the trabecular layer of the mandibular processes. The density of bone tissue of the cortical layer of the articular-fossa quadrant (A-Fh/q) of the articular head of the mandibular process increases on the right with limited defects and decreases with final defects. Indicators of bone densitometry of A-Fh/q on the left is characterized by a decrease with limited defects for individuals of the I-st period of adulthood and an increase in the final defects in the II-nd on the left and right. CONCLUSION: Conclusions: Multifactorial pathomorphological compensatory processes ensure bone density, but with a change in values on the right and a decrease on the left. Morphometric values of trabecular layers, the most vulnerable areas of the neck and base of the mandibular articular processes, indicate the reconstruc¬tion of their bone tissue with limited defects; in the first period of the adulthood, they decrease with a significant predominance on the left.

MORPHOMETRIC ANALYSIS OF TOPOGRAPHIC VARIABILITY OF THE LEFT AND RIGHT MANDIBULAR CANALS IN CASE OF LOSS OF THE MASTICATORY TEETH.

OBJECTIVE: The aim: To study the topographic variability of the left and right mandibular canals in case of bone atrophy caused by the loss of the masticatory teeth. PATIENTS AND METHODS: Materials and methods: 136 digital scans were selected for morphometric analysis, 68 for each side taken with the Vatech PaX-i 3D Green extra-oral radiography system. The readout of absolute morphometric values, laying the left and right MC was performed in the projection of 3.7, 3.6, 4.6, 4.7 teeth using standardized Ez3D-I software. RESULTS: Results: The alveolar part is characterized by distance to the alveolar ridge, and primarily exposed to pronounced atrophic processes of bone tissue. Distance to the lingual ridge directly proportionally indicates the morphological transposition vector of the mandibular canals for the distance to the buccal ridge, by the same length to its reduction. Morphometric analysis on a short toothless segment determines the variability of laying the mandibular canals but it is characterized by constant regular values of the ridge of the mandibular base. CONCLUSION: Conclusions: Dentition defects, moving towards the missing teeth, lead to a decrease in the biophysical stimulus on bone tissue, causing pronounced morphological changes with the loss of significant volume and restructuring of its trabecular layer, which synchronously affects the topographic variability of the left and right MC.