Histomorphometric analysis of condylar cartilage of diabetic rats after mandibular advancement using functional appliance with the use of low level laser therapy

Class II malocclusions with mandibular retrognathia could be treated by using functional appliances which promote condylar remodeling and accelerating forward mandibular growth. This process may be impaired by type 1 diabetes mellitus that demonstrates alterations in bone and mineral metabolism. The aim of this study was to evaluate the effects of type 1 diabetes mellitus on the condylar response during treatment with a functional appliance with the use of low level laser therapy. The sample consisted of 65 rats, weighting between 210 and 250 gr, divided randomly into 7 groups. Group 1 (n=5) was the control group, functional appliances were administrated to the group 2, 4, 5, 6, 7. Diabetes was induced in group 3, 4, 5, 6, 7 by administration of strepdozocin (STZ). The group 5, 7 were controlled with insulin. Group 6, 7 were treated with 8 J/cm2 low level laser. Histomorphometric analysis was performed for condylar cartilage thicknesses and new bone formation of mandibular condyle after 4 weeks. Results revealed significant differences between treated groups with the diabetic groups with no significant differences between diabetic groups (except group 3) and control group. Using appliance in insulin treated and healthy groups significantly affected the cartilage thickness and new bone formation parameters. The laser treatment showed significant changes in all parameters only in insulin treated group. Consequently, functional appliances were found to be more effective in healthy and insulin treated Diabetes Mellitus cases and laser therapy may be beneficial for remodelling process in Diabetes Mellitus cases which are under insulin control. Key Words: Functional appliances, Laser therapy, Mandibular advancement, Mandibular condyle, Type1 diabetes mellitus.