title: Prognosis of single molar implants: a retrospective study.
abstract: The purpose of this study was to evaluate the short- and mid-term prognosis of maxillary and mandibular single molar implants, prosthetic complications, and factors mediating the effects seen on them. Eighty-seven patients were enrolled consecutively in this study and 96 implants were placed into a single molar defect site by one oral and maxillofacial surgeon from March 2004 to December 2006. Primary osseointegration failure developed in two implants and delayed implant failure occurred at four implants. The fraction surviving interval was 97% to 100%, and at the last follow-up observation, the cumulative survival rate was 91.1%. All failed implants occurred in second molar sites, and the failure rate, according to implant site, showed a significant difference. Prosthetic complications, such as screw loosening, showed a significant correlation to the mesiodistal cantilever. Furthermore, crestal bone loss 3 years after loading was 0.2 mm on average and a very stable result was obtained. Based on the results, the risk of failure for maxillary and mandibular single molar implants is high and the possibility of developing prosthetic complications during loading is also high. Therefore, to minimize the cantilever, implants must be placed precisely and followed carefully and maintained for a long period of time.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Section of Dentistry, Seoul National University, Bundang Hospital, Seongnam City, Korea.
authors.forename: Young-Kyun
authors.initials: YK
authors.lastname: Kim
authors.forename: Su-Gwan
authors.initials: SG
authors.lastname: Kim
authors.forename: Pil-Young
authors.initials: PY
authors.lastname: Yun
authors.forename: Jung-Won
authors.initials: JW
authors.lastname: Hwang
authors.forename: Mee-Kyoung
authors.initials: MK
authors.lastname: Son
mesh_terms: D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging; D000539:Alveolar Process / Q000000981:diagnostic imaging; D000540:Alveolar Ridge Augmentation / Q000379:methods; D003442:Crowns; D019250:Dental Implants, Single-Tooth; D017267:Dental Prosthesis Design; D019232:Dental Restoration Failure; D005260:Female; D005500:Follow-Up Studies; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000601:surgery; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery; D008875:Middle Aged; D008963:Molar; D016348:Osseointegration / Q000502:physiology; D011379:Prognosis; D011859:Radiography; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult