The main focus of this research was to evaluate the ability of surface activated polymeric dental implants to induce and promote osseointegration. Interest in phosphonylated implants with hydroxyapatite-like surfaces capable of osseointegration with bone led to the development of a series of surface activated poly-ether-ether-ketone (PEEK) and carbon fiber reinforced (CFR-PEEK) endosteal dental implants (EDI) in preparation for in vivo comparison with a titanium alloy (Ti6-6Al-4V) implant of the same design. Concurrently, a unique endosteal implant design was developed with features to minimize radial and axial micromotion to aid in the long-term stability of the implant and minimize the potential for surgical revisions or complications following extended periods of use.; A pilot study was utilized to determine the efficacy of currently published methods for the evaluation of this unique series of implants in Beagles. Namely, immediate and delayed implant placement protocols were studied. We found that immediate placement presented certain challenges that were not able to be overcome, at least early on in this research.; In the main study, a series of fifteen Beagles were implanted with a total of 73 EDIs using the delayed placement method, revised extraction techniques and an improved EDI design. Multiple-member sets of ready-to-implant EDIs were made using orthogonal solid-state oriented PEEK (OSSO), carbon fiber-reinforced PEEK, and titanium alloy. At the conclusion of each study period for different EDIs, animals were euthanized and the implants subjected to torsional testing and histological evaluation. The peak torque (or maximum removal torque, MRT) required to disengage the EDI from surrounding bone tissue was measured. Additional samples were evaluated for histomorphometric and histopathological differences.; The biomechanical properties as measured by the maximal removal torque (MRT) were greatest for the CFR-PEEK EDIs across all time periods followed by the OSSO-PEEK and the lowest for the titanium alloy EDI. At 20 weeks of loading, the MRT values were as follows: CFR-PEEK = 117.9N-cm, OSSO-PEEK = 95.9N-cm and titanium alloy = 77.6N-cm. All values showed statistically significant differences when compared. The histomorphometric evaluation at 20 weeks of loading revealed the greatest percentage of the implant with attached bone for the CFR-PEEK EDI (65.8%), followed by the titanium alloy EDI (55.1%) and the OSSO-PEEK EDI (50.4%). The histomorphometric evaluation showed no difference between all three EDIs at 20 weeks.
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