Influence of interimplant distances and placement depth on peri-implant bone remodeling of adjacent and immediately loaded Morse cone connection implants: a histomorphometric study in dogs.
OBJECTIVE
The aim of this study was to histomorphometrically evaluate the influence of interimplant distances (ID) and implant placement depth on bone remodeling around contiguous Morse cone connection implants with 'platform-shifting' in a dog model.


METHODS
Bilateral mandibular premolars of six dogs were extracted, and after 12 weeks, each dog received 8 implants, four placed 1.5 mm subcrestally (SCL) on one side of the mandible and four placed equicrestally (ECL) on the other side, alternating the ID of 2 and 3 mm. The experimental groups were SCL with IDs of 2 mm (2 SCL) and 3 mm (3 SCL) and ECL with IDs of 2 mm (2 ECL) and 3 mm (3 ECL). Metallic crowns were immediately installed. After 8 weeks, the animals were euthanized and histomorphometric analyses were performed to compare bone remodeling in the groups.


RESULTS
The SCL groups' indices of crestal bone resorption were significantly lower than those of ECL groups. In addition, the vertical bone resorption around the implants was also numerically inferior in the SCL groups, but without statistical significance. No differences were obtained between the different IDs. All the groups presented similar good levels of bone-to-implant contact and histological bone density.


CONCLUSIONS
The subcrestal placement of contiguous Morse cone connection implants with 'platform shifting' was more efficient in preserving the interimplant crestal bone. The IDs of 2 and 3 mm did not affect the bone remodeling significantly under the present conditions.
Department of Bucco-Maxillo-Facial Surgery and Traumatology and Periodontology, School of Dentistry of Ribeirão Preto, University of São Paulo, São Paulo, SP, Brazil.
Raquel R M
RR
Barros
Arthur B
AB
Novaes
Valdir A
VA
Muglia
Giovanna
G
Iezzi
Adriano
A
Piattelli
D016301:Alveolar Bone Loss / Q000209:etiology / Q000517:prevention & control*; D000818:Animals; D015519:Bone Density; D016723:Bone Remodeling; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000009:adverse effects / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design / Q000009:adverse effects; D004285:Dogs; D020007:Implants, Experimental; D008297:Male; D013499:Surface Properties
D015921:Dental Implants