Early Bone Formation around Immediately Loaded Transitional Implants Inserted in the Human Posterior Maxilla: The Effects of Fixture Design and Surface

Abstract

Aim. To evaluate the effects of fixture design and surface on the early bone formation around immediately loaded implants inserted in the human posterior maxilla. Materials and Methods. Ten totally edentulous subjects received two transitional implants: one tapered implant with knife-edge threads/nanostructured calcium-incorporated surface (test: Anyridge®, Megagen, Gyeongbuk, South Korea) and one cylindrical implant with self-tapping threads/sandblasted surface (control: EZPlus®, Megagen). The implants were placed according to a split-mouth design and immediately loaded to support an interim complete denture; after 8 weeks, they were removed for histologic/histomorphometric analysis. The bone-to-implant contact (BIC%) and the bone density (BD%) were calculated. The Wilcoxon test was used to evaluate the differences. Results. With test implants, a mean BIC% and BD% of 35.9 (±9.1) and 31.8 (±7.5) were found. With control implants, a mean BIC% and BD% of 29.9 (±7.6) and 32.5 (±3.9) were found. The mean BIC% was higher with test implants, but this difference was not significant (p = 0.16). Similar BD% were found in the two groups (p = 0.9). Conclusions. In the posterior maxilla, under immediate loading conditions, implants with a knife-edge thread design/nanostructured calcium-incorporated surface seem to increase the peri-implant endosseous healing properties, when compared to implants with self-tapping thread design/sandblasted surface.

Scanning Electron Microscope (SEM) Evaluation of the Interface between a Nanostructured Calcium-Incorporated Dental Implant Surface and the Human Bone

“…Among the nanostructured, calcium-incorporated surfaces, there are surfaces enriched with calcium ions by a hydrothermal method, like Xpeed ® [24,32,33]. …”

“…Although several clinical studies have shown that dental implants with a nanostructured surface enriched with calcium ions through the hydrothermal method (Xpeed ® ) can have high survival and success rates, at least in the short term [10,36,37,38,39], still little is known about the mechanism of healing these fixtures in vivo [32,33]. …”

“…With this procedure, a nanolayer of Ca 2+ ions is incorporated onto the RBM surface, giving a CaTiO 3 nanostructure. Previous studies [24,32,33] have reported the following standard roughness parameters for this surface: a mean Ra (the arithmetic mean of the absolute height of all points) of 1.6 (±0.2) µm, a mean Rq (the square root of the sum of the squared mean difference of all points) of 2.1 (±0.3) μm, and a mean Rt (the difference between the highest and lowest points) of 15.7 (±0.2) μm. …”

“…The Xpeed ® surface (Megagen, Seoul, South Korea) is a nanostructured surface enriched with calcium ions through a hydrothermal method [24,32,33]. Histological and histomorphometrical studies on humans have confirmed that this nanostructured surface can support new bone formation, under an immediate loading protocol [32,33].…”

“…Histological and histomorphometrical studies on humans have confirmed that this nanostructured surface can support new bone formation, under an immediate loading protocol [32,33]. …”