Observations on healing following endodontic surgery in nonhuman primates (Macaca fascicularis): effects of rhBMP-2.
OBJECTIVE
The potential of recombinant human bone morphogenetic protein-2 (rhBMP-2) to enhance bone healing following endodontic surgery was tested. The pattern and timing of de novo bone formation and cementum regeneration, and the potential for root resorption and ankylosis to accompany bone formation were evaluated.


METHODS
Pulpal infections were induced in maxillary and mandibular incisor teeth in young adult Cynomolgus monkeys. The teeth received conventional endodontic treatment immediately followed by surgical root resection. In a randomized split-mouth design, contralateral apical bone defects received rhBMP-2 in absorbable collagen sponge (ACS) carrier or served as sham-surgery controls to provide histological and radiographic evaluations following 1 (mandibular incisors) and 4.5 (maxillary incisors) month(s) postsurgery.


RESULTS
At 1 month postsurgery trabecular bone filled the apical bone defects. The newly formed bone appeared considerably more mature and had assumed characteristics of the contiguous resident bone at 4.5 months postsurgery. The resected root tips were almost completely covered by new cementum with a maturing functionally oriented periodontal ligament. Localized inflammatory infiltrates were associated with the filled root canals and extruded root-filling material. Root resorption and ankylosis were not observed. There were no apparent differences in healing patterns between sites implanted with rhBMP-2/ACS and those serving as sham-surgery controls.


CONCLUSIONS
Under conditions where the influence of infectious elements and irritation caused by root filling material are minimized, bone formation and cementum regeneration appears rapid following endodontic surgery. rhBMP-2/ACS did not offer an obvious benefit above and beyond that of the native osteogenic potential in this animal model.
Bergenholtz
Gunnar
G
Faculty of Odontology, Göteborg University, Göteborg, Sweden. Gunnar.Bergenholtz@odontologi.gu.se
Wikesjö
Ulf M E
UM
Sorensen
Rachel G
RG
Xiropaidis
Andreas V
AV
Wozney
John M
JM
D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000209:etiology / Q000628:therapy*; D000818:Animals; D001047:Apicoectomy; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D001861:Bone Regeneration / Q000187:drug effects*; D003739:Dental Cementum / Q000502:physiology; D006801:Humans; D008252:Macaca fascicularis; D008297:Male; D010485:Periapical Periodontitis / Q000150:complications / Q000601:surgery; D010513:Periodontal Ligament / Q000502:physiology; D011859:Radiography; D011994:Recombinant Proteins / Q000494:pharmacology; D012038:Regeneration / Q000187:drug effects; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014945:Wound Healing / Q000187:drug effects*
C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta