Radiographic evaluation of pulpal and periapical response of dogs' teeth after pulpotomy and use of recombinant human bone morphogenetic protein-7 as a capping agent.
OBJECTIVE
The purpose of this study was to evaluate radiographically the pulpal and periapical response of dogs' teeth after pulpotomy and the use of recombinant human bone morphogenetic protein-7 (rHuBMP-7).


METHODS
Pulpotomies were performed in 60 teeth of 6 dogs, and the remaining radicular pulp tissue was capped with the following materials: (a) groups 1 and 5-recombinant human bone morphogenetic protein-7 associated with recombinant human-like collagen; (b) groups 2 and 6-recombinant human-like collagen; (c) groups 3 and 7-calcium hydroxide; and (d) groups 4 and 8-zinc oxide and eugenol cement. After 7 days (groups 1-4) and 70 days (groups 5-8), standardized periapical radiographs were taken and the integrity of the lamina dura, presence of areas of periapical bone rarefaction, internal/external root resorption, and dentin bridge formation were evaluated. The results were analyzed statistically by Fisher's exact test and Bonferroni correction. The radiolucent areas suggestive of periapical lesions associated with the roots were measured in mm2, and the results were compared by Kruskal-Wallis test.


RESULTS
In the 7-day period, all specimens in groups 1 to 4 presented intact lamina dura and absence of periapical bone rarefaction, internal/external root resorption or dentin bridge formation. In the 70-day period, no specimen in groups 5, 6, and 8 presented dentin bridge formation. Periapical bone rarefaction areas were observed to be associated with 100%, 60%, and 40% of the roots in group 6, 8, and 5, respectively. The largest lesions were found in group 6, followed by groups 5 and 8 (P<.05). In group 7, there was dentin bridge formation in 60% of the cases and intact lamina dura and no periapical bone rarefaction in all specimens.


CONCLUSIONS
The use of rHuBMP-7/rHuCollagen as a capping material after pulpotomy did not induce mineralized tissue deposition, leading to the formation of radiographically visible periapical lesions.
da Silva
Léa Assed Bezerra
LA
Department of Pediatric Clinics, Preventive and Social Dentistry, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
de Paula e Silva
Francisco Wanderley Garcia
FW
Leonardo
Mário Roberto
MR
Assed
Sada
S
D016301:Alveolar Bone Loss / Q000139:chemically induced* / Q000000981:diagnostic imaging; D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000187:drug effects; D000818:Animals; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000633:toxicity*; D002126:Calcium Hydroxide / Q000494:pharmacology; D003094:Collagen / Q000494:pharmacology; D003782:Dental Pulp / Q000187:drug effects* / Q000378:metabolism; D003785:Dental Pulp Capping / Q000009:adverse effects / Q000379:methods*; D003809:Dentin, Secondary / Q000000981:diagnostic imaging / Q000378:metabolism; D004285:Dogs; D005260:Female; D006801:Humans; D008297:Male; D011672:Pulpotomy / Q000379:methods*; D011859:Radiography; D011994:Recombinant Proteins / Q000633:toxicity; D012391:Root Resorption / Q000000981:diagnostic imaging*; D016212:Transforming Growth Factor beta / Q000633:toxicity*; D015035:Zinc Oxide-Eugenol Cement / Q000633:toxicity
C525819:BMP7 protein, human; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; D015035:Zinc Oxide-Eugenol Cement; D003094:Collagen; D002126:Calcium Hydroxide