The impact of operator access on implant surface roughness following implantoplasty procedures. An in vitro study.

Abstract

This in vitro investigation sought to determine whether access to the implant during implantoplasty (IP) exerts a significant influence on the resulting surface roughness and material loss, by comparing outcomes obtained in a phantom head model versus a tabletop model. Secondary objectives were to compare the surface roughness and material loss resulting from IP among three commercially available dental implant systems, and to assess differences between the buccal and lingual aspects of implants in the phantom head model.

Implants from three different implant systems, Straumann®, Ankylos®, and Sweden & Martina®, were used. A total of 42 implants were utilised. 21 implants, seven of each implant type, were mounted in either the tabletop or phantom head model. The implants on the tabletop model were mounted in a vice, giving the operator unrestricted access to the surface during IP. Implants in phantom head models were mounted into casts in the 36 sites using a customised jig. A standardised bur sequence was employed for IP of all implants, and a single operator performed all IP procedures. Two tungsten carbide burs with different blade anatomy were used, followed by a final surface polishing sequence with silicone polishers. This sequence was applied consistently across all implant types and both models, with implant removal from the models after.

Surface profilometry was conducted using a Surftest Sj-210 contact stylus profilometer (Mitutoyo Europe GmbH, Neuss, Germany) in order to measure surface roughness in the form of Ra and Rz values. To provide qualitative data, images using a Carl Zeiss EVO LS10 (Zeiss, Oberkochen, Germany) were taken of select implant surfaces. In addition, implant mass and width were measured before and after the IP. The amount of time needed for each IP procedure was also measured using a Garmin ® Venu ® 2 Plus (Garmin International Inc., Olathe, USA).

Descriptive statistics (means with standard deviations, and medians with interquartile ranges) were calculated for all measured parameters. The Shapiro-Wilk test was used to assess normality. Inferential statistics compared outcomes between model settings and among implant systems using parametric or non-parametric tests, with post-hoc adjustments for multiple comparisons. A significance threshold of p < 0.05 was applied.

After IP, implants in the phantom head setting achieved a median Ra value of 0.53 μm (0.49 - 0.58 μm) compared to those in the tabletop setting of 0.44 μm (0.37 - 0.62 μm) (p 0.004). In addition, implants in the phantom model achieved a significantly increased Rz of 2.47 μm (1.98 - 2.75 μm) compared to 2.78 μm (2.56 - 3.01 μm)(p = 0.019). Procedural time was significantly less for implants prepared in standardised tabletop conditions (685 sec [648 - 738]) compared to those prepared in a simulated clinical environment in phantom heads (765 sec [733 - 800.50])(p < 0.001).

Material loss varied among implant systems, with Straumann® implants exhibiting a greater reduction in mass and width than Ankylos® and Sweden & Martina® implants. No significant differences between implant types were found for Ra and Rz (p > 0.05). In addition, there were no significant differences in Ra and Rz between the buccal and lingual aspects of the implants in the phantom head setting overall and for the implant types.

The results demonstrate that IP can effectively reduce the surface roughness of dental implants, though the final surface roughness and procedural time are affected by operator access. In addition, no significant differences in final surface roughness were observed between the different implant types following IP. Associated material loss (mass and width reduction) appears to be influenced by implant macro-design, such as thread density and thread depth.