title: Changes in proximal contact tightness between fixed implant prostheses and adjacent teeth: A 1-year prospective study.
abstract: BACKGROUND
  No study has evaluated consecutive changes in proximal contact tightness (PCT) between fixed implant prostheses and adjacent teeth after delivery.
  
  
  OBJECTIVE
  The purpose of this clinical study was to investigate consecutive biological changes in PCT between fixed implant prostheses and adjacent teeth after placement.
  
  
  METHODS
  Eighteen participants who had been treated with a single first molar implant in the mandible were included. Mesial and distal PCT were measured using the custom-made contact pressure system at immediate crown delivery (T0), 3-month follow-up (T1), and 1-year follow-up (T2). The PCT of natural teeth in the mesial direction of the same quadrant was also measured at T2 as a control. Repeated-measures analysis of variance (ANOVA) and 1-way ANOVA were used for statistical analysis.
  
  
  RESULTS
  At T0, the PCT between fixed implant prostheses and adjacent teeth was designed deliberately to be higher than the PCT between natural teeth. Using multivariate analyses, the PCT between fixed implant prostheses and adjacent teeth decreased between T0 and T1 (P<.001), while there was no significant difference between T1 and T2 (P=.506). At T2, the distal PCT was tighter than the mesial PCT (P<.001); however, no statistical difference was found in the PCT between the implant-supported restoration and the natural teeth.
  
  
  CONCLUSIONS
  PCT decreased significantly at both mesial and distal sites over time. The major changes occurred over the 3-month period after crown delivery.
authors.affiliation: Attending, Department of Implantology, Peking University School of Stomatology, Beijing, China.
authors.forename: Shuxin
authors.initials: S
authors.lastname: Ren
authors.affiliation: Professor, Department of Implantology, Peking University School of Stomatology, Beijing, China. Electronic address: yorcklin@263.net.
authors.forename: Ye
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Associate Professor, Department of Implantology, Peking University School of Stomatology, Beijing, China.
authors.forename: Xiulian
authors.initials: X
authors.lastname: Hu
authors.affiliation: Attending, Department of Implantology, Peking University School of Stomatology, Beijing, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
mesh_terms: D015921:Dental Implants; D019094:Dental Prosthesis, Implant-Supported; D003779:Denture Design; D003830:Denture, Partial, Fixed; D005500:Follow-Up Studies; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000534:rehabilitation*; D008644:Mesial Movement of Teeth / Q000473:pathology*; D011446:Prospective Studies
chemical_list: D015921:Dental Implants