Treatment of intrabony defects with guided tissue regeneration and enamel-matrix-proteins. An experimental study in monkeys.
BACKGROUND
Enamel matrix proteins (EMD) have recently been introduced in regenerative periodontal treatment. However, no histological data are yet available concerning the effect of treating intrabony periodontal defects with EMD, and no histological comparisons have been made comparing the result of treatment of intrabony defects with EMD with that of the treatment with guided tissue regeneration (GTR).


OBJECTIVE
Therefore, the aim of the present study was to evaluate histologically in monkeys the effect of treating intrabony defects with EMD, GTR or combined EMD and GTR.


METHODS
Intrabony periodontal defects were produced surgically at the distal aspect of teeth 14, 11, 21, 24, 34, 31, 41 and 44 in 3 monkeys (Macaca fascicularis). In order to prevent spontaneous healing and to enhance plaque accumulation metal strips were placed into the defects. After 6 weeks the defects were exposed using a full-thickness flap procedure. The granulation tissue was removed and the root surfaces were debrided by means of hand instruments. Subsequently, the defects were treated using one of the following therapies: (i) GTR, (ii) EMD, or (iii) combination of EMD and GTR. The control defects were treated with coronally repositioned flaps. After 5 months, the animals were sacrificed and perfused with 10% buffered formalin for fixation. Specimens containing the defects and surrounding tissues were dissected free, decalcified in EDTA and embedded in paraffin. 8 microm thick histological sections were cut and stained and subsequently examined under the light microscope.


RESULTS
In the control specimens, the healing was characterized by a long junctional epithelium and limited periodontal regeneration (i.e., new periodontal ligament, new cementum with inserting connective tissue fibers and new bone) in the bottom of the defect. The GTR-treated defects consistently presented periodontal regeneration when the membranes were not exposed whereas the sites treated only with EMD presented regeneration to a varying extent. The combined therapy did not seem to improve the results.


CONCLUSIONS
It can be concluded that all 3 treatment modalities favor periodontal regeneration.
Sculean
A
A
Department of Periodontology and Conservative Dentistry, University of the Saarland, Homburg, Germany. zmkascu@krzsun.med-rz.uni-sb.de
Donos
N
N
Brecx
M
M
Reich
E
E
Karring
T
T
D016301:Alveolar Bone Loss / Q000601:surgery*; D000818:Animals; D001861:Bone Regeneration; D003746:Dental Enamel Proteins / Q000627:therapeutic use*; D016557:Guided Tissue Regeneration, Periodontal; D008252:Macaca fascicularis; D008297:Male; D010514:Periodontal Pocket / Q000601:surgery
D003746:Dental Enamel Proteins; C109069:enamel matrix proteins