Purpose: It is hypothesised that systemic calcitonin delivery with adjunct local platelet-rich fibrin (PRF) therapy is more effective in augmenting osseointegration than calcitonin delivery alone under experimental osteoporosis conditions. The primary objective of the present experiment was to assess the effect of systemic calcitonin delivery with and without adjunct local PRF therapy on osseointegration in ovariectomised osteoporotic rabbits.
Materials and methods: Thirty female bilaterally ovariectomized rabbits were used. The animals were fed a low-calcium diet to establish a model for osteoporosis. In each animal, 2 implants were bilaterally placed in tibia. The animals were randomly divided equally into 3 groups. In group 1, no treatment was offered (control group). In groups 2 and 3, the animals received intramuscular injections of calcitonin without and with local PRF delivery prior to implant placement, respectively. All animals were euthanised at 12 weeks, and osseointegration was assessed as the gap widths between the bone and implant surface in the cervical, middle and apical third using scanning electron microscopy and energy-dispersive x-ray spectroscopy. The bone-to-implant contact (BIC) was also measured. p < 0.05 was defined as statistically significant.
Results: Gap widths in the cervical (p < 0.001), middle (p < 0.001) and apical third (p < 0.001) were statistically significantly higher in group 1 than groups 2 and 3. Gap widths in the cervical (p < 0.001), middle (p < 0.001) and apical third (p < 0.001) were significantly higher in group 3 than group 2. The mean BIC was statistically significantly higher in the cervical (p < 0.001), middle (p < 0.001) and apical third (p < 0.001) in group 3 compared with groups 2 and 3.
Conclusions: When used as an adjunct to calcitonin, PRF enhanced osseointegration in an experimental osteoporosis model. However, further well-designed studies with inclusion of additional groups (treatment with PRF alone) are needed.
Keywords: gap junctions; osseointegration; osteoporosis; platelet rich fibrin; calcitonin.