Pages 777-784, Language: EnglishCarr / Gerard / Larsen
Important to the understanding of the dynamics associated with dental implant anchorage over time is a knowledge of the supporting anatomy for common endosseous implants prior to being placed into function. This study followed 20 screw-shaped dental implants placed in edentulated (2 months' healing time) posterior jaws of five adult female baboons. Implants made of three biomaterials were placed and allowed to heal for 3 months prior to processing for evaluation. Percentage integration and bone area data from six horizontal sections along the entire length of each implant were collected and analyzed for differences between jaws, implant biomaterials, jaw/biomaterial, and sections of the implants (ANOVA, pairwise comparison using LSM with Bonferroni adjustment). The results indciated that overall mean percentage integration was 46.5 and mean percentage bone area was 39.9. Maxillary and mandibular differences for both parameters were statistically different (integration: maxillary = 38.1%, mandibular = 56.7%, bone area: maxillary = 35.8%, mandibular 44.9%; both were significant at the P < .05 level). The biomaterial analyses revealed significant differences for percentage integration between the metal implants and the hydroxyapatite-coated implant (commercially pure titanium = 39.1%, titanium-aluminum-vanadium = 40.0%, hydroxyapatite-coated = 61.5%), but no such difference was noted for percentage bone area (commerically pure titanium = 38.8%, titanium-aluminum-vanadium = 38.9%, hydroxyapatite-coated = 42.3%). Discussion of the relative importanceof the two parameters highlights the fact that resi stance to functional loads requires establishing and then maintaining an adequate volume of bone, which may have a functionally specific structure based on the mechanical properties of the local jaw environment.