@Article{, title={Time-related salivary cathepsin B levels and periodontal status in different orthodontic force magnitudes}, author={Maha Abdul Aziz Ahmed مها عبد العزيز احمد and Haraa S. Mohammed-Salih and Yassir A. Yassir and Hikmat J. Al-Judy حكمت جميل الجودي}, journal={Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد}, volume={27}, number={2}, pages={115-122}, year={2015}, abstract={Background: Biologically active substances, such as Cathepsin B (CAB) which is a lysosomalcystein protease may beinvolved in periodontal metabolism in the degradation of organic bone matrix containing collagen fibers in responseto mechanical stress from orthodontic appliance. The aims of study were to determine and compare salivary levelsof CAB, pH as well as clinical periodontal parameters (Plaque index PLI and gingival index GI) with differentorthodontic force magnitudes at different time intervals.Materials and methods: A twenty-four patients (both gender) with age range (17-23) years had Angle's Class IIdivision 1 malocclusion with GI <0.5 enrolled in this study. The level of salivary CAB and pH, in addition to the clinicalperiodontal parameters (PLI and GI) were measured before (baseline), 1 hour (1H), 1 day (1D), 1week (1W), 2 weeks(2W) and 3 weeks (3W) after fixed orthodontic appliance placement with different forces applied to the teeth (F1 (40gm), F2 (60 gm) and F3 (80 gm)).Results: The highest mean concentration of salivary CAB was (12.057) at F1 in 1D visit with highly significantdifferences among the visits as well as among the forces (p≤0.05). Weak correlations were revealed between all pairsof forces as well as between each visit with the baseline visit about salivary CAB except the strong negativecorrelations between F1 with F3 at 3W and baseline with 3W visits at F3. Maintenance of good oral hygiene duringthe study period demonstrated that the highest mean values of PLI and GI were (0.2) and (0.25) respectively, inaddition to the non-significant differences regarding pH among the visits.Conclusion: The concentration of salivary CAB was increased following fixed orthodontic appliance insertion. Thevery light continuous orthodontic force could produce significant increase of this enzyme activity and give enougheffectiveness to produce tooth movement as compared to the higher forces

} }