Relationships between biochemical bone metabolism indices and morphometric, densitometric and mechanical properties of mandible in 6-month-old pigs.

INTRODUCTION AND OBJECTIVE Mandible is used as a bone model for monitoring bone tissue responses to various factors influencing skeletal homeostasis. Considering the lack of experimental data on interrelationships between bone metabolism indices and morphometric, densitometric and mechanical properties of mandible, the aim of this study was to perform such an evaluation in 6-month-old pigs. MATERIALS AND METHODS Quantitative computed tomography was used to determine bone volume, mean volumetric bone mineral density, cortical bone density and cortical bone area. Using dual-energy X-ray absorptiometry, bone mineral density and bone mineral content were measured for ramus, body and whole jaw. In the three-point bending test, maximum elastic strength and ultimate strength of jaw was determined. Assessment of calcium (Ca), phosphorus (P), magnesium (Mg), parathormone (PTH), growth hormone (GH), insulin-like growth factor-1 (IGF-1), alkaline phosphatase (ALP), bone-specific alkaline phosphatase (BAP), osteocalcin (OC) and C-terminal telopeptide of collagen type-I (CTX) in blood was performed. RESULTS Statistically significant correlations in relation to the investigated traits of the jaw were found in the case of ALP, OC, CTX, GH and IGF-1. Significant correlations of ALP activity, OC and IGF-1 concentrations with final body weight were stated (p<0.05). CONCLUSIONS This study shows the highest predictive value of ALP activity determination in relation to assessment of morphological, densitometric and biomechanical properties of mandible. Evaluation of Ca, P, Mg, BAP and PTH has not confirmed its significance for morphological, densitometric and biomechanical properties prediction in the jaw of pigs. ALP activity, OC and IGF-1 concentrations would be prognostic for body weight prediction.