title: Crestal bone remodeling in loaded and unloaded implants and the microgap: a histologic study.
abstract: OBJECTIVE
  The aim of this study was to histologically evaluate the crestal bone response to loaded and unloaded implants in beagle dogs.
  
  
  METHODS
  Sand-blasted and acid-etched implants (Bone System, Milano, Italy) were placed in the mandible of six beagle dogs. The two premolars and the first molars had been extracted 3 months previously. Each dog received 12 implants in the mandible, and a total of 72 implants were used in this study. Three months after implantation, second-stage surgeries were performed for placement of abutments or healing screws. Three dogs were killed after 6 months, and three dogs were killed after 12 months. All 72 implants were retrieved.
  
  
  RESULTS
  No statistically significant differences were found in the amount of bone loss between test and control implants, both at 6 and 12 months. Statistically significant differences were found, in both groups, between the bone loss observed at 6 months and that found at 12 months.
  
  
  CONCLUSIONS
  Loading does not seem to be a relevant factor in the peri-implant bone resorption observed during the first year of function. Our results support previous findings that bone crest level changes could depend on the location of the microgap.
authors.affiliation: Dental School, University of Chieti, Italy.
authors.forename: Bartolomeo
authors.initials: B
authors.lastname: Assenza
authors.forename: Antonio
authors.initials: A
authors.lastname: Scarano
authors.forename: Giovanna
authors.initials: G
authors.lastname: Petrone
authors.forename: Giovanna
authors.initials: G
authors.lastname: Iezzi
authors.forename: Ulf
authors.initials: U
authors.lastname: Thams
authors.forename: Fidel
authors.initials: F
authors.lastname: San Roman
authors.forename: Adriano
authors.initials: A
authors.lastname: Piattelli
mesh_terms: D000134:Acid Etching, Dental; D000539:Alveolar Process / Q000473:pathology*; D000704:Analysis of Variance; D000818:Animals; D016723:Bone Remodeling / Q000502:physiology*; D001862:Bone Resorption / Q000473:pathology; D000044:Dental Abutments; D045662:Dental Etching; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D004285:Dogs; D005260:Female; D008297:Male; D008334:Mandible / Q000473:pathology* / Q000601:surgery; D016348:Osseointegration / Q000502:physiology; D013314:Stress, Mechanical; D013499:Surface Properties; D013997:Time Factors
chemical_list: D015921:Dental Implants