| 摘要: | BACKGROUND: Biological complications in implant dentistry are referred to as peri-implantitis,
which is an inflammatory process that affects the soft and hard tissues around an implant and results in
loss of attachment. As peri-implantitis associated with biofilm development, the characteristics of
titanium implants may influence biofilm formation, and thereby increase the risk for inflammation.
Thus, titanium implant surface roughness induced by different methods of debridement should be
analyzed in detail in terms of primary periodontal pathogen adherence.
OBJECTIVE OF THE STUDY: This in vitro study intends to evaluate the effect of titanium surface
roughness induced by 4 different debridement methods of peri-implant, such as metallic ultrasonic
scaler, rubber polishing cup, gallium-aluminum-arsenide (GaAlAs) diode laser and chlorhexidine
(CHX) rinse on Porphyromonas gingivalis (P. gingivalis) adhesion mechanism.
MATERIALS AND METHODS: Commercially pure titanium discs with different surface treatments
served as substrates for the adherence of P. gingivalis in this study. Surface debridement was
performed by immersing titanium discs into chlorhexidine mouth rinse for 24 hours or treating titanium
discs with diode laser, rubber polishing cup and ultrasonic scaler for 60 seconds continuously. Nontreated
discs were used as controls. Following treatment, surface topography was examined using
profilometer. For the bacterial assay, specimens were separately inoculated with P. gingivalis for 2
hours and subsequently incubated for 6, 12 and 24 hours. After designated incubation time, bacterial
adhesion on the discs was quantified by spectrophotometric evaluation of the slime production by the
bacteria. Moreover, scanning electron microscope images were analyzed to quantify the extent of P.
gingivalis adhesion and colonization on the titanium surfaces. Data were analyzed by one-way
ANOVA and Pearson’s correlation test (p < 0.05).
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RESULTS: The average surface roughness (Ra) obtained for all surfaces ranged from 0.177 to 0.517,
with small standard deviation. Scaled surfaces showed the highest Ra values to be at high significant
differences comparing with other titanium group surfaces (p < 0.001). There were a significant positive
correlation between surface roughness and optical density measurements at all incubation time (p <
0.05). The quantitative evaluation of P. gingivalis attachment through SEM revealed that the amount of
bacteria were significantly lower on control, laser and CHX groups compared with other groups (p <
0.05). Moreover, a significant positive correlation was found between Ra and attached P. gingivalis
number obtained from SEM images (p < 0.05).
CONCLUSION: Polishing, CHX and laser treatments on titanium surfaces provided best reduction in
P. gingivalis biofilm mass and re-growth, when studied in vitro. This effect was enhanced as the
smoothness of the titanium surface was increased. |
