title: Compromised primary implant stability.
abstract: The aim of this study was to evaluate implants installed with compromised primary stability associated or not with polylactide and polyglycolide copolymer (PLA/PGA). Two 0.4-mm overdrilled defects (3 mm in diameter and 6 mm long) were produced in the right tibia of 25 rabbits. Half of the defects were left untreated, and the other half was filled with PLA/PGA. Implants of 2.6 mm in diameter and 6 mm long were placed into all defects. Animals were killed at 5, 15, 40, and 60 postoperative days, and biomechanical analysis (torque-reverse), histomorphometry, and immunohistochemistry (osteoprotegerin, receptor activator of NF-κB ligand [RANKL], osteocalcin, and collagen-1 [COL-I] staining) were performed. All the implants achieved osseointegration. There were no statistically significant differences in the torque-reverse and in linear contact extension between bone tissue and implant surface and no statistically significant difference in osteoprotegerin, RANKL, osteocalcin, and collagen-1 expression between the studied groups in all studied periods (P > 0.05). We can conclude that osseointegration can occur in compromised primary implant stability situations, and the addition of PLA/PGA did not improve the osseointegration process in this experimental model.
authors.affiliation: Department of Health Sciences, Implantology Post Graduation Course, Dental School, University Center of Araraquara-UNIARA, Araraquara, São Paulo, Brazil. thaqueiroz@hotmail.com
authors.forename: Thallita Pereira
authors.initials: TP
authors.lastname: Queiroz
authors.forename: Francisley Ávila
authors.initials: FÁ
authors.lastname: Souza
authors.forename: Roberta
authors.initials: R
authors.lastname: Okamoto
authors.forename: Eloa Rodrigues
authors.initials: ER
authors.lastname: Luvizuto
authors.forename: Rogério
authors.initials: R
authors.lastname: Margonar
authors.forename: Idelmo Rangel
authors.initials: IR
authors.lastname: Garcia
authors.forename: Eduardo
authors.initials: E
authors.lastname: Hochuli Vieira
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D003758:Dental Implantation, Endosseous / Q000379:methods*; D017267:Dental Prosthesis Design; D007150:Immunohistochemistry; D020007:Implants, Experimental; D008297:Male; D008855:Microscopy, Electron, Scanning; D016348:Osseointegration; D011091:Polyesters; D011100:Polyglycolic Acid; D011817:Rabbits; D013499:Surface Properties; D013977:Tibia / Q000601:surgery*; D019415:Torque
chemical_list: D001672:Biocompatible Materials; D011091:Polyesters; D011100:Polyglycolic Acid; C033616:poly(lactide)