Moringa oleifera leaf extract promotes the healing of critical sized bone defects in the mandibles of rabbits

Abstract

Objective: The search for an osteopromotive material that enhances the efficacy of alloplasts in reconstructive surgeries has been going on for years. This study aimed to histologically and histomorphometrically evaluate the efficiency of Moringa oleifera leaf extract as an osteopromotive biomaterial.

Design: The study is a prospective randomized controlled animal study. 24 adult male New Zealand rabbits were equally allocated into test and control groups. Critical-sized bone defects were created in the edentulous areas of the mandibles of rabbits. The defects of the control group were filled with Beta-tricalcium Phosphate, while the defects of the test group were filled with Beta-tricalcium Phosphate combined with Moringa oleifera leaf extract. The results were evaluated histologically and histomorphometrically.

Results: Histological and histomorphometric analysis showed a significant increase in the surface area of bone and the number of osteoblasts in test groups compared to those in the control groups.

Conclusion: Moringa oleifera leaf extract has a positive effect on bone regeneration in critical-sized bone defects.

Fig. 1. Flowchart of the study design showing the random allocation of the rabbits into test and control groups, the follow-up periods, and the methods of evaluation.

Rabbits were randomly divided into a control group and an experimental group, in which each group included 12 New Zealand rabbits. Animals were then euthanized and mandibles were prepared for histological evaluation and histomorphometric evaluation for statistical analysis.

Fig. 2. The dimensions of the surgically induced standardized critical sized defects performed in 24 defects.

A 3 mm apico-coronal dimension. B 6 mm mesiodistal dimension. C 4 mm buccolingual dimension.

Fig. 3. Histologic differences between experimental and control groups 4 weeks post-operatively.

A Control group showing numerous blood vessels containing red corpuscles of red blood cells are found in the marrow spaces surrounding the newly formed bone trabeculae. (H&E; original magnification ×100). B Test group shows a huge amount of blood vessels with marrow spaces surrounding the trabeculae of the newly formed bone (H&E; original magnification ×100). C Control group light micrograph showing mature bone within defect with wide marrow spaces of moderate vascularity (Masson’s trichrome; original magnification ×100). D Test group light micrograph showing newly formed bone lined by active osteoblast. Fibrous mapping of newly formed trabeculae is also noticed. (Masson’s trichrome; original magnification ×100).

Fig. 4. Histological differences between test and control groups 8 weeks postoperatively.

A Control group shows the intermingle between graft particles (arrows) and the formed mature bone. (H&E; original magnification ×100). B Test group shows the newly formed bone that is lined by active plump osteoblasts (thick arrow) and contains numerous osteocytes (thin arrows). (H&E; original magnification ×100). C Light micrograph of the control group showing bone trabeculae within defect with marrow spaces of moderate vascularity (Masson’s trichrome; original magnification ×100). D Light micrograph of the test group showing mature bone within the defect, the marrow spaced show evident fibrous tissue and moderate vascularity. (Masson’s trichrome; original magnification ×100).

Fig. 5. Graph shows the significant difference in the percentage of the surface area of bone in comparison to the total surface area of the defect after 4 and 8 weeks in both the test and control groups with 95% confidence interval.

After 1 month, the range of percentage of surface area of bone in comparison to the total surface area of the defect in the control group ranges between 16.77% and 23.36% with a mean of 19.42%, while in the test group the percentage ranged from 27.72% to 38.34%. After 2 months, the range of percentage of surface area of bone in comparison to the total surface area is from 25.07% to 39.92% with a mean of 33.78% for the control group while for the test group the percentage ranged from 33.34% to 44.99% with a mean of 41.12%.

Fig. 6. Comparison between Osteoblast count per photomicrograph in the study and control groups after 4 and 8 weeks with 95% confidence interval.

The figure shows that the range of number of osteoblasts per photomicrograph for the control group after 1-month ranges from 69 to 81 with a mean of 77 osteoblasts while the number of osteoblasts per photomicrograph for the test group after 1 month ranged from 97 to 108 with a mean of 101.86. After 2 months, the number of osteoblasts per photomicrograph for the control group ranged from 56 to 68 with a mean of 61.71 while for the test group it ranged from 67 to 75 with a mean of 70.43 osteoblasts per photomicrograph.