Clinical and histological evaluation of the effect of magnesium oxide administration on relapse after orthodontic teeth movement (Rabbit Model Study)

Abstract

Objective: This study aimed to evaluate the clinical and histological administration of magnesium oxide (MgO) supplementation on orthodontic relapse and bone remodeling.

Materials and methods: Twenty male albino rabbits were classified into four groups (five animals for each as two control (positive and negative), plus two experimental (low dose 40 mg/kg) and (high dose 80 mg/kg)/b.w. daily). An orthodontic force was applied (40 gm) to the lower incisors using modified orthodontic appliance adapted on the lower central incisors. During the period of retention, MgO was given orally. Relapse was estimated after appliance removal. A digital Calliper was used to compete the space between incisors' mesial tips of rabbits at six successive time points (0, 3, 7, 10, 15, and 21 days). Histologically, osteoblast, osteoclast, and osteocyte account were assessed. Data analyses were performed by SPSS using ANOVA and Tukay HSD (P ≤ 0.05) for statistically significant differences between groups.

Results: The high dose group had a lower relapse rate than the low dose and control groups. Histologically, the high dose group had more osteoblasts and osteocytes than low dose and control groups. While osteoclasts were significantly lower than the control group in low and high dose groups.

Conclusions: MgO supplementation during an orthodontic retention phase, particularly at a level of high dose, clinically decreased orthodontic relapse in a rabbit model. Histologically, MgO has a significant effect on alveolar bone after the orthodontic retention period.

Keywords: MgO; orthodontic teeth movement; osteoblast; osteoclast; relapse.

Figure 1

Illustrated Microscopic examination of tissue sections by, H and E stain, 400X revealed presence of (a) the coronal side by thickening of periodontal ligament (PDL), congestion blood vessels (C) and inflammatory cells infiltration. (b) coronal side normal architecture of osteoblast (OB), osteocytes (OC) and osteoclast (OCL), H and E stain, 400X (C) middle side by thickening of periodontal ligament (PL) with hemorrhage (H), erosion in the edge of trabecular bone (E), congestion blood vessels (C) and mild inflammatory cells infiltration surrounding it. (d) middle side with normal architecture of osteoblast (OB), osteocytes (OC) and osteoclast (OCL) (e) apical side with thickening of periodontal ligament (PL) and severe inflammatory cells infiltration surrounding it, inflammatory cells infiltration surrounding it, (f) apical normal architecture of osteoblast (OB), osteocytes (OC) and osteoclast (OCL)

Figure 2

Illustrated Microscopic examination of tissue sections by, H and E stain, 400X revealed presence of (a) coronal side representing by congestion of blood vessels in the periodontal ligament (C), increased numbers of osteoblasts in the trabecular bone (OB) and growing of newly woven bone formation (WB), (b) coronal side with normal architecture of osteoblast (OB), osteocytes (OC) and osteoclast (OCL), (c) middle side with filling of eroded part of trabecular bone with granulation tissue (GT) containing immature connective tissue (ICT) and angiogenesis, H and E stain, 400X inflammatory cells infiltration surrounding it, (d) middle side with normal architecture of osteoblast (OB), osteocytes (OC) and osteoclast (OCL) (e) apical side with congestion of blood vessels in the periodontal ligament (C) and presence of newly woven bone formation surrounding trabecular bone (WB), inflammatory cells infiltration surrounding it, H and E (f) apical side with normal architecture of osteoblast (OB), osteocytes (OC) and osteoclast (OCL), H and E stain, 400X

Figure 3

Illustrated Microscopic examination of tissue sections by, H and E stain, 400X revealed presence of (a) coronal side with congestion blood vessels in the periodontal ligament (C) and increased numbers of osteoblasts in the trabecular bone (OB), (b) coronal side with normal architecture of osteoblast (OB), osteocytes (OC) and osteoclast (OCL) (c) middle side with increase numbers of blood vessels in the periodontal ligament (BV) and increased numbers of osteoblasts in the trabecular bone (OB), (d) middle side with normal architecture of osteoblast (OB), osteocytes (OC) and osteoclast (OCL), (e) apical side representing by present of granulation tissue (GT) with immature connective tissue (ICT) and angiogenesis (An) and presence of newly woven bone formation (WB), (f) apical side with normal architecture of osteoblast (OB), osteocytes (OC) and osteoclast (OCL)