Histomorphometric Analysis of the Bone-Implant Contact Obtained with 4 Different Implant Surface Treatments Placed Side By Side in the Dog Mandible

Histomorphometric Analysis of the Bone-Implant Contact Obtained with 4 Different Implant Surface Treatments Placed Side By Side in the Dog Mandible A. B. Novaes, Jr, S. L. S. Souza, P. T. de Oliveira, et al, Int J Oral Maxillofac Implants. 2002;17:377–383 The goal of this investigation was to compare the effects of four different implant surfaces on bone-to-implant contact. This goal is introduced as being of potential importance through a very succinct review of issues important to implant surface texture and osseointegration. The implant surfaces compared in this investigation were a machined surface, titanium plasma sprayed (TPS), hydroxyapatite (HA), and the study sponsor’s roughened surface, soluble blasting media (SBM). This study uses a dog model in which four implants, with one implant of each surface type, were placed in the premolar regions on each side of the mandible. Implants were allowed to heal for 12 weeks before histomorphometric analysis of bone-to-implant contact. The histomorphometric analysis was carried out by a blinded examiner. The results of this investigation report mean ± SD levels of bone contact after 12 weeks for the four surfaces of 41.7 ± 7.8% (machined), 57.9 ± 18% (HA), 48.9 ± 21.1% (TPS), and 68.5 ± 18.8% (SBM). Statistical analysis did find that there was a significant difference based on surface types, and secondary analysis suggested that this significance was due to differences between the machined surface and the SBM surface. However, given the multiple statistical comparisons performed, the significance should be viewed as borderline. The authors rightly conclude that their results are consistent with a number of reports that suggest that early bone formation along the implant surface may be enhanced with a roughened texture. As the authors point out, the SBM surface may have a numerical advantage over the other surfaces tested. However, these results should be viewed in a guarded manner, as the results were not statistically different. Overall, this study supports previous findings that roughened surfaces enhance early bone-to-implant contact, and that the study sponsor’s SBM surface does respond similarly to other roughened surfaces. However, the study design does limit the strength of even these conclusions. For example, given the similarities in implant designs studied, the position of the implants could have been randomized, and much of the surgical placement could have been performed in a blinded manner as well. It is also interesting to consider that the SBM surface was developed as an improvement relative to other blasted surfaces, yet there were no blasted surfaces compared in this study.