The effects of calcitonin on post‐orthodontic relapse in rats

Abstract

Objectives To determine the effects of systematic calcitonin administration on post‐orthodontic relapse in rat model. Material and methods This experimental animal model involved 36 male Wister rats. The maxillary right first molars were moved mesially, using a modified orthodontic appliance delivered 50 gm, for 14 days, retained for 4 days and left to relapse for 10 days. The study group was divided into three subgroups in which a single injection of calcitonin (20 IU/Kg), three injections of calcitonin (20 IU/Kg), each every other day, and normal saline were administered subcutaneously after orthodontic tooth movement has finished. The relapse ratio, histomorphometric analysis including osteoblasts, osteoclasts numbers and bone area and immunohistochemical analysis including the expression of receptor activator of nuclear factor kappa Β (RANK), receptor activator of nuclear factor kappa Β ligand (RANKL) and osteoprotegerin (OPG) were measured and assessed. Results The relapse ratio was significantly reduced in the three‐dose calcitonin group (28%) compared to the single dose calcitonin group (34%) and the control group (46%). This was accompanied by a nonsignificant increase in osteoblasts number and bone area in three‐dose calcitonin group and a nonsignificant reduction in osteoclast number. However, the immune histochemical expression of RANK, RANKL and OPG did not show statistically significant difference at the end of relapse period. Conclusions Systemic administration of three doses of calcitonin may minimize the relapse ratio in experimentally moved rat molars.

The Effect of Nano Calcium Carbonate and/or Recombinant Bone Morphogenetic Protein as a Biological Orthodontic Retainer on the Body Weight of Experimental Rat

“…Moreover, in order to preserve the fixed orthodontic appliance during the whole treatment period, the food texture should be changed to soft food and avoid any hard diet that may cause a fracture of the inserted fixed appliance. The results of this study showed that the BW of animals in all studied groups was reduced significantly over time which comes in agreement with the results of previous studies that also found a reduction of BW of experimental rats following the movement of teeth using fixed orthodontic appliance although some variations were observed which could be related to the other cofounders of each study [12,18]. This reduction in BW could be related to the abovementioned issues which associated with the insertion of an orthodontic appliance that may induce pain and interfere with normal eating resulting in a decrease in BW that is directly proportional to the presence of an orthodontic appliance which was confirmed by more weight loss in 9-week group compared to the 6-week group.…”

Effect of vitamin D deficiency on postorthodontic relapse: An animal study

“…One of the most important concerns in orthodontics is the retention of the teeth after orthodontic treatment (Proffit et al, 2019). Previous research used local applications of biological agents, such as statins, strontium, bisphosphonates, tetracycline, raloxifene, and calcitonin, to decrease the amount of relapse (Al-Duliamy et al, 2015;Alnajar & Al Groosh, 2020;Azami et al, 2020;Hudson et al, 2012;Veginadu et al, 2020;Vieira et al, 2019). However, local applications have some drawbacks, such as the short half-life of the agents, which requires multiple applications, and health-related issues associated with prolonged administration (Arqub et al, 2021).…”

“…After fixation, the specimens were washed thoroughly with running water and rinsed in 10% EDTA solution (BDH Chemicals Ltd.) with a pH of 7 for 21 days, which was changed every alternative day, to decalcify the teeth and the bone (Alnajar & Al Groosh, 2020;Plut et al, 2015;Sarsfield, 2000). After decalcification, each maxilla was dissected into two halves, and each half involved three maxillary molar teeth (Adachi et al, 1994;Al-Duliamy, et al, 2015).…”

Effects of vitamin D deficiency on bone and root resorption post-orthodontic retention in rats

“…The rats were anesthetised after being weighed using intramuscular injection of ketamine (87 mg/kg; ketamine 10%, Alfasan, Woerden, Holland) and xylazine muscle relaxant (10 mg/kg; XYL-M2 injectable solution 25 mL, VMD, Arendonk, Belgium) at a 2:1 ratio (21) , that is in thigh muscle based on the animal housing guidelines in CCMGR. This process was applied in all orthodontic stages.…”

“…Bonding adhesive was applied (3M ESPE, Adper, single bond 2, USA), and composite filling materials (3M ESPE, Filtek, Z350 XT, Universal Restoration, USA) were adapted and cured according to the manufacturer's instructions (Fig. 1A) (21) .…”