New Acid Etched Titanium Dental Implant Surface

SUMMARY The purpose of this investigation was to create an acid etched implant surface that results in a surface similar to that gained by using sandblasting combined with acid etching and to compare it with surfaces of commercially available screw-type implants. Titanium grade V discs were machined in preparation for acid etching. Tests were carried out using different acids and their combinations with variable time exposures. All etched surfaces were scanned with electron microscope (JEOL JSM-5600, Japan) and digital images were made for visual evaluation and description of the surfaces. The etched surfaces were evaluated for surface morphology (combination of micro roughness and waviness) and were best attained by a combination of sulphuric and hydrochloric acids. The etched titanium discs were fixed in resin (two were cut and polished and two – scored and fractured) and the surface profile was examined in. The second part of the investigation used screw-shaped titanium implants. Twenty-eight screwshaped implants that were manufactured from commercially available titanium grade V, were selected and divided into two groups: 3 implants as controls (machined surface) and 25 implants processed using the etching methods used in the first part of the investigation. Magnifications of 27, 200 and 2000 were used to analyse the first two consecutive crests of threads, flanks and root of threads of each implant with the treated surface. A three-dimensional optical interferometer (MicroXam, Phase-Shift, USA) was used to characterize the surface roughness of both control and test groups. Three screws were selected from each group and measured at 9 sites: 3 measurements each on the crest, root and flank of the threads. To describe the surface roughness in numbers, the following parameters were used: the average height deviation (Sa), the developed interfacial area ratio (Sdr), the fastest decay autocorrelation length (Sal) and the density of summits (Sds). Surfaces of 5 commercially available screw-type implants and the experimental ones were comparatively analyzed. It was concluded that the new experimental etched titanium surface had features of a roughened titanium surface with glossily micro-roughness and large waviness. In general, the experimental surface was significantly rougher than the selected commercially available implants and similar to SLA treated surface (top Sa 2,08µm (SD 0,36); Sdr 1,34µm (SD 0,3); valley – 1,16µm (SD 0,1) and 0,68µm (SD 0,1); flank – 2,24µm (SD 0,8) and 1,27µm (SD 0,1) respectively).