title: Persistent acute inflammation at the implant-abutment interface.
abstract: The inflammatory response adjacent to implants has not been well-investigated and may influence peri-implant tissue levels. The purpose of this study was to assess, histomorphometrically, (1) the timing of abutment connection and (2) the influence of a microgap. Three implant designs were placed in the mandibles of dogs. Two-piece implants were placed at the alveolar crest and abutments connected either at initial surgery (non-submerged) or three months later (submerged). The third implant was one-piece. Adjacent interstitial tissues were analyzed. Both two-piece implants resulted in a peak of inflammatory cells approximately 0.50 mm coronal to the microgap and consisted primarily of neutrophilic polymorphonuclear leukocytes. For one-piece implants, no such peak was observed. Also, significantly greater bone loss was observed for both two-piece implants compared with one-piece implants. In summary, the absence of an implant-abutment interface (microgap) at the bone crest was associated with reduced peri-implant inflammatory cell accumulation and minimal bone loss.
authors.affiliation: Department of Periodontics, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA.
authors.forename: N
authors.initials: N
authors.lastname: Broggini
authors.forename: L M
authors.initials: LM
authors.lastname: McManus
authors.forename: J S
authors.initials: JS
authors.lastname: Hermann
authors.forename: R U
authors.initials: RU
authors.lastname: Medina
authors.forename: T W
authors.initials: TW
authors.lastname: Oates
authors.forename: R K
authors.initials: RK
authors.lastname: Schenk
authors.forename: D
authors.initials: D
authors.lastname: Buser
authors.forename: J T
authors.initials: JT
authors.lastname: Mellonig
authors.forename: D L
authors.initials: DL
authors.lastname: Cochran
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000044:Dental Abutments / Q000009:adverse effects*; D003758:Dental Implantation, Endosseous / Q000009:adverse effects* / Q000379:methods*; D015921:Dental Implants / Q000009:adverse effects*; D017267:Dental Prosthesis Design / Q000009:adverse effects; D004285:Dogs; D016018:Least-Squares Analysis; D007958:Leukocyte Count; D007963:Leukocytes, Mononuclear; D008334:Mandible; D009504:Neutrophils; D010518:Periodontitis / Q000209:etiology* / Q000276:immunology / Q000473:pathology; D011897:Random Allocation
chemical_list: D015921:Dental Implants