title: Peri-implant conditions and their relationship with periodontal conditions in Chinese patients: a cross-sectional study.
abstract: OBJECTIVE
  To analyze the relationships between peri-implant conditions and periodontal conditions in Chinese patients with dental implants in place for at least 1 year.
  
  
  METHODS
  Seventy-six patients (mean age, 41 ± 10 years; range, 21-69 years) who received placement of 120 dental implants (Straumann(®) ), (mean 1.6 implants per subject; range, 1-5 implants per subject) after a mean period of 25 months (range, 12-66 months) responded to recall. Clinical examinations were performed around the implants and natural teeth. Periapical radiographs were taken by the long cone technique for implants, and radiographic bone level (BL) was measured. Comparisons of the peri-implant conditions were performed between the patients with different periodontal conditions by t-test and chi-square test. The relative risk of periodontal condition as a risk factor for peri-implant conditions was analyzed by logistic regression.
  
  
  RESULTS
  Subjects who presented with ≥5% sites with probing depth (PD) ≥ 4 mm and ≥30% sites with bleeding on probing (BoP) in the dentition showed significantly poorer peri-implant conditions (58% vs. 18% subjects who had maximum modified gingival index (mGI) 2 or 3, P = 0.003; 94% vs. 62% subjects who had maximum PD ≥ 4 mm, P = 0.008; 100% vs. 79% subjects who had BoP, P = 0.044; mean PD 3.36 ± 0.66 vs. 2.75 ± 0.66 mm, P = 0.002; and sites% with BoP 68 ± 23% vs. 36 ± 31%, P < 0.001), as compared with those who had <5% sites with PD ≥ 4 mm and <30% sites with BoP on the remaining teeth. The relative risk for subjects with the more severe and extensive periodontal conditions compared to those with better periodontal conditions to have PD ≥ 5 mm with BoP at peri-implant sites was 23.3 (P = 0.003, 95% CI, 2.8-192.3.
  
  
  CONCLUSIONS
  The peri-implant conditions were significantly related to the periodontal conditions around the remaining natural teeth, which implies that control of periodontal disease is essential for successful implant treatment.
authors: The Second Dental Center, Peking University School of Stomatology, Beijing, China.
authors: R
authors: R
authors: Wang
authors: The Second Dental Center, Peking University School of Stomatology, Beijing, China.
authors: W
authors: W
authors: Zhao
authors: The Second Dental Center, Peking University School of Stomatology, Beijing, China.
authors: Z H
authors: ZH
authors: Tang
authors: Faculty of Dentistry, Periodontology, The University of Hong Kong, Hong Kong, China.
authors: L J
authors: LJ
authors: Jin
authors: Department of Periodontology, Peking University School of Stomatology, Beijing, China.
authors: C F
authors: CF
authors: Cao
mesh_terms: D000328:Adult; D000368:Aged; D002681:China; D003430:Cross-Sectional Studies; D003758:Dental Implantation, Endosseous / Q000009:adverse effects*; D015921:Dental Implants / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010510:Periodontal Diseases / Q000000981:diagnostic imaging* / Q000209:etiology* / Q000517:prevention & control; D011859:Radiography; D012307:Risk Factors
chemical_list: D015921:Dental Implants
keywords: location of crown margin; peri-implant disease; periodontal disease; plaque; risk factor; susceptibility