Enamel matrix derivative versus guided tissue regeneration in the presence of nicotine: a histomorphometric study in dogs.
OBJECTIVE
The goal of this histometric study was to compare the healing process of dehiscence-type defects treated by enamel matrix derivative (EMD) or guided tissue regeneration (GTR) under the effect of nicotine in the dog model.


METHODS
Eight mongrel dogs were used. Buccal osseous dehiscences were surgically created on the mesial roots of the mandibular third and fourth pre-molars. The defects were exposed to plaque accumulation for 3 months. After this period, the defects were randomly assigned to one of the treatments: open flap debridement (OFD), EMD or GTR with a resorbable membrane. During 4 months, the dogs received subcutaneous administration of nicotine (2 mg/kg twice a day with a 12 h interval between the applications). After this period, the animals were killed and the blocks were processed. The histometric parameters evaluated included gingival recession, epithelial length, connective tissue adaptation, new cementum and new bone.


RESULTS
A superior length of new cementum was observed in the sites treated by EMD in comparison with OFD (p< or =0.05). No statistically significant differences were observed between GTR and the other groups.


CONCLUSIONS
In the presence of nicotine, EMD may promote more new cementum formation than OFD while GTR failed to provide a significant difference.
Pimentel
Suzana Peres
SP
Department of Prosthodontics and Periodontics, Division of Periodontics, School of Dentistry at Piracicaba, State University of Campinas (UNICAMP), Av. Limeira 901, Areião, São Paulo, Brazil.
Sallum
Antonio Wilson
AW
Saldanha
Juliana Bezerra
JB
Casati
Márcio Zaffalon
MZ
Nociti
Francisco H
FH
Sallum
Enilson A
EA
D020341:Absorbable Implants; D016301:Alveolar Bone Loss / Q000473:pathology / Q000601:surgery*; D000539:Alveolar Process / Q000473:pathology; D000818:Animals; D001672:Biocompatible Materials / Q000627:therapeutic use*; D003238:Connective Tissue / Q000473:pathology; D003367:Cotinine / Q000097:blood; D003646:Debridement; D003739:Dental Cementum / Q000473:pathology; D003746:Dental Enamel Proteins / Q000627:therapeutic use*; D003773:Dental Plaque / Q000150:complications; D004195:Disease Models, Animal; D004285:Dogs; D004846:Epithelial Attachment / Q000473:pathology; D005889:Gingival Recession / Q000473:pathology; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D007279:Injections, Subcutaneous; D008567:Membranes, Artificial; D009538:Nicotine / Q000008:administration & dosage* / Q000097:blood; D018722:Nicotinic Agonists / Q000008:administration & dosage* / Q000097:blood; D011897:Random Allocation; D013524:Surgical Flaps; D014945:Wound Healing / Q000502:physiology
D001672:Biocompatible Materials; D003746:Dental Enamel Proteins; D008567:Membranes, Artificial; D018722:Nicotinic Agonists; C109069:enamel matrix proteins; D009538:Nicotine; D003367:Cotinine