Clinical and microbiological analysis of subjects treated with Brånemark or AstraTech implants: a 7-year follow-up study.
OBJECTIVE
To assess the impact of different implant systems on the clinical conditions and the microbiota at implants, and whether the presence of bacteria at tooth sites was predictive of the presence at implant sites.


METHODS
Subjects with either AstraTech or Brånemark in function for 7 years were enrolled. Sub-gingival bacterial samples at tooth and implant sites were collected with sterile endodontic paper points, and analyzed by the checkerboard DNA-DNA hybridization method (40 species).


RESULTS
Fifty-four subjects, 27 supplied with AstraTech (n=132 implants) and 27 with Brånemark (n=102) implants, were studied. Test tooth sites had significantly less evidence of bleeding on probing (P<0.001) and presence of plaque (P<0.001) than implant test sites. Implant sites presented with deeper probing pocket depth than tooth sites (mean difference: 1.1 mm, standard error of differences: 0.08, 95% confidence intervals (CI): 0.9-1.3, P<0.001). Tannerella forsythia (P<0.05), Capnocytophaga sputigena (P<0.05), Actinomyces israelii (P<0.05) and Lactobacillus acidophilus (P<0.05) were found at higher levels at tooth surfaces. No differences in bacterial load for any species were found between the two implant systems. The odds of being present/absent at tooth and implants sites were only significant for Staphylococcus aureus [odds ratio (OR): 5.2 : 1, 95% CI: 1.4-18.9, P<0.01].


CONCLUSIONS
After 7 years in function, implants presented with deeper probing depths than teeth. S. aureus was commonly present at both teeth and implants sites. S. aureus at tooth sites was predictive of also being present at implant sites.
Renvert
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Department of Health Sciences, Kristianstad University, Kristianstad, Sweden. stefan.renvert@hkr.se
Lindahl
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Renvert
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Persson
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D000190:Actinomyces / Q000302:isolation & purification; D000328:Adult; D000368:Aged; D001421:Bacteria, Anaerobic; D004269:DNA, Bacterial; D003758:Dental Implantation, Endosseous; D015921:Dental Implants / Q000382:microbiology*; D003774:Dental Plaque Index; D017267:Dental Prosthesis Design; D005260:Female; D005500:Follow-Up Studies; D006090:Gram-Negative Bacteria; D006801:Humans; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization; D016017:Odds Ratio; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000382:microbiology*; D011237:Predictive Value of Tests; D013211:Staphylococcus aureus / Q000302:isolation & purification; D018709:Statistics, Nonparametric
D004269:DNA, Bacterial; D015921:Dental Implants