M. Quirynen et al., AN IN-VIVO STUDY OF THE INFLUENCE OF THE SURFACE-ROUGHNESS OF IMPLANTS ON THE MICROBIOLOGY OF SUPRAGINGIVAL AND SUBGINGIVAL PLAQUE, Journal of dental research, 72(9), 1993, pp. 1304-1309
In nine patients with fixed prostheses supported by endosseous titaniu
m implants, 2 titanium abutments (transmucosal part of the implant) we
re replaced by either an unused standard abutment or a roughened titan
ium abutment. After 3 months of habitual oral hygiene, plaque samples
were taken for differential phase-contrast microscopy, DNA probe analy
sis, and culturing. Supragingivally, rough abutments harbored signific
antly fewer coccoid micro-organisms (64 us. 81%), which is indicative
of a more mature plaque. Subgingivally, the observations depended on t
he sampling procedure. For plaque collected with paper points, only mi
nor qualitative and quantitative differences between both substrata co
uld be registered. However, when the microbiota adhering to the abutme
nt were considered, rough surfaces harbored 25 times more bacteria, wi
th a slightly lower density of coccoid organisms. The presence and den
sity of periodontal pathogens subgingivally were, however, more relate
d to the patient's dental status than to the surface characteristics o
f the abutments. These results justify the search for optimal surface
smoothness for all intra-oral and intra-sulcular hard surfaces for red
uction of bacterial colonization and of periodontal pathogens.