The effects of combined glucosamine sulfate and chondroitin sulfate supplements on condylar cartilage remodeling during functional appliance therapy. A Micro-CT study.

摘要

Glucosamine and chondroitin sulphate supplementation is used to prevent the degeneration of articular surfaces and also to enhance repair and regeneration of cartilage. The ability for adaptation of condylar cartilage to mandibular forward positioning is what constitutes the fundamental rationale for orthodontic functional therapy, which partially contributes to the correction of jaw discrepancies in growing Skeletal II mandibular retrusive patients. The purpose of this study was to qualitatively and quantitatively analyse the effect of Glucosamine sulphate (GS) and Chondroitin sulphate (CS) supplementation on condylar remodeling with functional appliance therapy in rats. One hundred and forty 3-week-old female Sprague-Dawley rats were randomly divided into 4 groups consisting of; baseline controls, supplementation only, functional appliances only and those receiving both supplements and functional appliances. Supplements were preloaded for a period of 2 weeks prior to the placement of functional appliances at five weeks of age. The animals were sacrificed at days 0, 7 and 21 after appliance placement. The appliances were removed in the remaining experimental animals on day 21 with sacrifice on day 28 to analyse post growth modification changes. Condylar samples were then soaked in 0.2 M Gadolinium Chloride (GdCl3) (aq) for 6 days and analyzed using micro-computed tomography (μCT) for morphological characteristics and linear and volumetric measurements of the mandibular condyle. The results demonstrated supplement therapy increased the volume of cartilage with and without functional appliance therapy. Functional appliance therapy alone resulted in increases in cartilage volume over untreated animals, with peak volume increases occurring by day 7 of appliance wear followed with decreases as endochondral ossification ensued. Supplement therapy was found to enhance the normal biological response to functional appliance therapy in the rat model.