OBJECTIVETo investigate the effect of minocycline hydrochloride ointment on cell attachment and proliferation on titanium disks.

METHODSCommercially pure (grade 4) machined titanium discs with three different kinds of surfaces (smooth, acid-etched and sandblasted combined with acid-etched) were treated with minocycline ointment for 1 week, and then cleaned in ultrasonic cleanser for 10 minutes. Surface properties were examined by scanning electron microscope (SEM) and roughness tester before and after the treatment. Surface roughness was compared by paired t test. MG-63 (human osteoblast-like osteosarcoma cell) cells were seeded on these three kinds of discs with or without minocycline treatment, and methl thiazolyl tetrazolium (MTT) was performed to investigate the attachment in the 1st day and proliferation in the 4th and 7th day. Data were analyzed by double factor analysis of variance.

RESULTSSurface roughness before and after minocycline application was as follows, Smooth: (0.093 ± 0.025) µm, (0.086 ± 0.026) µm; Acid-etched: (1.100 ± 0.095) µm, (1.009 ± 0.196) µm; Sandblasted combined with acid-etched: (2.837 ± 0.283) µm, (2.968 ± 0.206) µm. No significant changes in roughness were found before and after minocycline application (P values were 0.118, 0.436 and 0.692). SEM examination revealed as similar surface configuration after minocycline application as before, except for some remnant of the minocycline ointment in acid-etched and sandblasted combined acid-etched groups. In MTT test, the growth of MG-63 cells in the 1 st, 4th day and 7th day was not different between groups with and without minocycline application (P values were 0.450, 0.848 and 0.835), and among three groups of different surface (P values were 0.184, 0.579 and 0.331).

CONCLUSIONSMinocycline hydrochloride ointment did not affect the surface configuration, surface roughness or the properties for cell attachment and proliferation of titanium discs.