title: Sleeping vs. loaded implants, long-term observations via a retrospective analysis.
abstract: OBJECTIVE
  Several theories have been presented to explain initial and secondary marginal bone loss around dental implants (e.g. microbial load, adverse loading, microbial leakage, compromised healing/adaptation of host-implant interface).
  
  
  METHODS
  This study compared the long-term outcome (up to 12 years) of sleeping with loaded implants in the mandible via a split-mouth concept. Fourteen patients with overdentures were enrolled (10 women, mean age at implant insertion: 56 years [range: 33-71]). They presented with 28 loaded (position 33/43) and 14 sleeping implants (mostly position 31/41). At several follow-up visits, intra-oral radiographs (long-cone principle) were taken to observe marginal bone level changes.
  
  
  RESULTS
  At each observation, compared with abutment connection, the submerged non-loaded implants showed less bone loss (P-values: 1st year 0.007, 3 years 0.000, 5 years 0.002, 8 years 0.007, 12 years 0.000) than their neighbouring functional implants. This difference was primarily due to a more significant bone loss during the first year of loading (0.8 vs. 0.1 mm respectively), since afterwards, the bone level changes remained quite similar for both implant types.
  
  
  CONCLUSIONS
  Our data suggest that the first months of loading have a significant impact on the bone level (initial difference sleeping vs. loaded implants), followed by a more physiological bone level change afterwards. This initial difference might be explained by the adaptation of the surrounding bone to the loaded implant.
authors: Department of Periodontology, School of Dentistry, Oral Pathology & Maxillo-Facial Surgery, Faculty of Medicine, Catholic University Leuven, Kapucijnenvoer 33, B-3000, Leuven, Belgium.
authors: K
authors: K
authors: Marcelis
authors: M
authors: M
authors: Vercruyssen
authors: E
authors: E
authors: Nicu
authors: I
authors: I
authors: Naert
authors: M
authors: M
authors: Quirynen
mesh_terms: D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000209:etiology*; D000044:Dental Abutments; D015921:Dental Implants; D003828:Denture, Overlay; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000601:surgery; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D012890:Sleep
chemical_list: D015921:Dental Implants