n3-PUFA coated titanium implants promote osseointegration in mandibular bone (animal study)

Abstract

BACKGROUND: The use of dental implant coating based on an organic acid, such as eicosapentaenoic acid (EPA) with an ability of osteoconduction could be a promising treatment for some challenging cases of patients with a history of radiotherapy or patients with diabetes, osteoporosis, and other patients with poor wound healing. Biocompatibility and adequate biomechanical properties are the main requirements in determining the clinical success of any type of dental implant. Omega-3 highly polyunsaturated fatty acid (n-3-PUFA) in a form of Eicosapentaenoic acid (EPA) has been detected to provide advantageous effects on bone remodelling and biology. Ultimately, n-3-PUFA, including EPA, has been verified to positively influence bone health and skeletal biology. AIM/HYPOTHESIS: Hypothesis was set that EPA-coated dental implants might 1) increase the osteoconduction process, verified by a significant difference between the test and control side of the same implant by testing the axial pull-out test of the implants. 2) increase the rate of new bone formation on the implant surface verified by Cone Beam Computed Tomography (CBCT) and Xray findings. MATERIAL AND METHODS: The current animal study was approved by the ethical committee of the University according to the regulations of (IACUC). Twenty four planar titanium plates (5 9 59 1 mm) were surgically fixed half way into the mandibular bone of twelve white New Zealand rabbits. The rabbits were randomly assigned into three study groups (n = 4). The planar implants were coated with EPA on one side and were highly polished on the other side. CBCT was used to inspect the bone-implant interface assessing the density and the new bone formation on the exposed part of the implant. The specimens were analysed by radiographs to the implants and the neighbouring bone structure to analyse osteoconductive bone formation at the coated side and to compare it with the bone at the control side. Axial pull-out tests were performed to the specimens to test osseointegration. Non-parametric Kruskal-Wallis test and multiple time series comparisons Friedman’s test were employed. Both analyses were set at significance level of P < 0.05 to compare differences in the amount of implant covered by new bone formation between the coated and the not coated implant surfaces in different time intervals. Osseointegration was analysed by comparing the amount of force, as an action of axial pull-out test, after periods of 4, 8, and 12 weeks respectively. RESULTS: By using CBCT and radiographs, osteoconductive bone formation was estimated at the coated test side of Ti compared to the polished non-coated side 4 weeks postoperatively. Statistical results showed significant difference after 8 weeks (P = 0.05) on the EPA-coated side compared to the non-coated side. Also, statistical analyses revealed a significant difference (P = 0.01) between the amount of pull-out force after eight and 12 weeks, compared to 4 weeks. CONCLUSION AND CLINICAL IMPLICATIONS: In the current experiments, the set up was designed to investigate the outcome of coating dental implants with EPA on osteoconduction after fixation in the mandibles of rabbits. As titanium implant fixture coating, EPA coating seems to enhance the anchorage between bone and external fixation of the Ti prosthesis. EPA-based implant coating stimulates osteoconduction processes in rabbits. This coating might increase bone healing processes after implant surgery.