title: The effect of implant diameter on osseointegration utilizing simplified drilling protocols.
abstract: OBJECTIVE
  To observe and to compare histologically and histomorphometrically, the combined effect of drilling sequence and implant diameter in vivo.
  
  
  METHODS
  A total of 72 alumina-blasted and acid-etched Ti-6Al-4V implants with three different diameters (3.75, 4.2, and 5 mm, n = 24 for each group) were placed in the right and left tibiae of 12 beagle dogs. Within the same diameter group, half of the implants were inserted after a simplified drilling procedure (pilot drill + final diameter drill) on one tibia and the other half were placed using the conventional drilling procedure on the other tibia. After 1 week, half of the animals (n = 6) were sacrificed, and the other half was sacrificed after 5 weeks (n = 6). The retrieved bone-implant samples were subjected to non-decalcified histologic sectioning, and the bone-to-implant contact (BIC) and the bone area fraction occupancy (BAFO) were analyzed. Primary statistical analysis used a mixed model analysis of variance with significance level set at P < 0.05.
  
  
  RESULTS
  Histologic observation showed that at 1 week, immature woven bone formed in vicinity of the implant, whereas at 5 weeks, the woven bone was replaced by lamellar bone, which formed in proximity with the implant. Histomorphometrically, the simplified technique was associated with significantly greater BIC and BAFO after 1 week. Differences between techniques were not longer apparent after 5 weeks, but BAFO was inversely and significantly associated with implant diameter at that time.
  
  
  CONCLUSIONS
  The simplified technique did not impair either early or late bone formation for any tested implant diameter; however, wider diameters were associated with less bone formation at longer healing times for both techniques.
authors.affiliation: Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö, Sweden.
authors.forename: Ryo
authors.initials: R
authors.lastname: Jimbo
authors.affiliation: Department of Epidemiology and Health Promotion, New York University, New York, NY, USA.
authors.forename: Malvin N
authors.initials: MN
authors.lastname: Janal
authors.affiliation: Department of Dentistry, Division of Oral and Maxillofacial Surgery, Universidade Federal de Santa Catarina, Brazil.
authors.forename: Charles
authors.initials: C
authors.lastname: Marin
authors.affiliation: Department of Biomaterials and Biomimetics, New York University, New York, NY, USA.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Giro
authors.affiliation: Department of Biomaterials and Biomimetics, New York University, New York, NY, USA.
authors.forename: Nick
authors.initials: N
authors.lastname: Tovar
authors.affiliation: Department of Biomaterials and Biomimetics, New York University, New York, NY, USA.
authors.forename: Paulo G
authors.initials: PG
authors.lastname: Coelho
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000497:Alloys; D000537:Aluminum Oxide / Q000737:chemistry; D000818:Animals; D000069343:Bone-Implant Interface / Q000033:anatomy & histology; D003722:Dental Alloys / Q000737:chemistry; D045662:Dental Etching / Q000379:methods; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D004285:Dogs; D023421:Models, Animal; D016348:Osseointegration / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology; D010027:Osteotomy / Q000379:methods*; D013499:Surface Properties; D013977:Tibia / Q000601:surgery; D013997:Time Factors; D014025:Titanium / Q000737:chemistry
chemical_list: D000497:Alloys; D003722:Dental Alloys; D015921:Dental Implants; C031462:titanium alloy (TiAl6V4); D014025:Titanium; D000537:Aluminum Oxide
keywords: animal experiments; bone implant interactions; surgical techniques