title: Effect of opposing implant prostheses on periodontal pathogens in dentures: A pilot study.
abstract: BACKGROUND
  An understanding of the presence of periodontal pathogens in denture plaque is important for the treatment of patients with edentulism. However, current data are limited and inconclusive.
  
  
  OBJECTIVE
  The purpose of this pilot clinical study was to investigate whether opposing implant prostheses affect the presence of periodontal pathogens in maxillary complete dentures.
  
  
  METHODS
  Twenty adult participants were enrolled in the study. The complete denture (CD/CD) group included 7 participants with complete maxillary and mandibular dentures. The implant overdenture (CD/IOD) group included 13 participants with maxillary complete-denture opposing implant overdentures. Plaque from maxillary complete dentures was collected and genomic DNA was extracted. Periodontal pathogens included Aggregatibacter actinomycetemcomitans, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia, and the total bacteria numbers were determined by real-time polymerase chain reaction (PCR) assay. A comparison of the detection rates and levels of periodontal pathogens between the 2 groups was performed using the chi-square test and the Mann-Whitney U test, respectively. Associations among these pathogens were determined using the Spearman rank correlation coefficient.
  
  
  RESULTS
  No significant differences (P>.05) in detection rates were found between the CD/CD and CD/IOD groups for A actinomycetemcomitans (100% versus 100%, respectively), E corrodens (71.4% versus 76.9%, respectively), F nucleatum (100% versus 69.2%, respectively), Porphyromonas gingivalis (100% versus 100%, respectively), P intermedia (57.1% versus 84.6%, respectively), and T forsythia (100% versus 92.3%, respectively). No significant differences in periodontal pathogen levels (P>.05) were observed between the 2 groups. Significant positive associations were observed (P<.05) between F nucleatum and P intermedia, F nucleatum and T forsythia, F nucleatum and P gingivalis, P intermedia and P gingivalis, P intermedia and A actinomycetemcomitans, T forsythia and P gingivalis, T forsythia and A actinomycetemcomitans, and P gingivalis and A actinomycetemcomitans.
  
  
  CONCLUSIONS
  Six investigated periodontal pathogens were widely present in denture plaque. Wearing opposing implant overdentures did not affect the presence and levels of the periodontal pathogens.
authors.affiliation: Research Associate, Center for Dental Research, Loma Linda University School of Dentistry, Loma Linda, Calif. Electronic address: zhou121@hotmail.com.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Professor, Advanced Specialty Education Program in Prosthodontics, Loma Linda University School of Dentistry, Loma Linda, Calif.
authors.forename: Mathew T
authors.initials: MT
authors.lastname: Kattadiyil
authors.affiliation: Research Associate, Center for Dental Research, Loma Linda University School of Dentistry, Loma Linda, Calif.
authors.forename: Raydolfo M
authors.initials: RM
authors.lastname: Aprecio
authors.affiliation: Visiting scholar, Center for Dental Research, Loma Linda University School of Dentistry, Loma Linda, Calif.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Liu
authors.affiliation: Professor, Center for Dental Research, Loma Linda University School of Dentistry, Loma Linda, Calif.
authors.forename: Wu
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Professor, Center for Dental Research, Loma Linda University School of Dentistry, Loma Linda, Calif; and Associate Dean, Research, School of Dentistry, Loma Linda, Calif.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Li
mesh_terms: D000328:Adult; D001419:Bacteria / Q000302:isolation & purification*; D003773:Dental Plaque / Q000382:microbiology*; D003774:Dental Plaque Index; D003824:Denture, Complete / Q000382:microbiology*; D006801:Humans; D010519:Periodontium / Q000382:microbiology*; D010865:Pilot Projects