Periodontal wound healing following GTR therapy of dehiscence-type defects in the monkey: short-, medium- and long-term healing.
OBJECTIVE
To describe periodontal wound healing in dehiscence-type defects following guided tissue re-generation (GTR) therapy.


METHODS
Ten adult Macaca fascicularis monkeys were used. Buccal dehiscence-type defects were created at the maxillary second pre-molars and second molars. After 3 months, GTR surgery was performed. The animals were euthanized at 6 weeks, 6 months and 2 years after surgery. Block biopsies were harvested, and prepared for histological analysis.


RESULTS
A new attachment apparatus was structured already after 6 weeks of healing. A 10-20 microm thin layer of acellular extrinsic fibre cementum (AEFC) had formed along the instrumented root surface. At 6 months, the thickness of the supracrestal cementum was comparable with that at 6 weeks, while the thickness of the subcrestal cementum had increased to 40-60 microm. In this zone, the cementum consisted of an inner layer of AEFC attached to the circum-pulpal dentin and an outer layer of cellular mixed fibre cementum (CMFC). The numerical extrinsic fibre density was twice that at 6 weeks. At 2 years, the periodontal tissues resembled the pristine periodontium.


CONCLUSIONS
Periodontal healing following GTR therapy of recession-type defects will result in a restitutio ad integrum, i.e. healing by re-generation. A continuous maturation process occurs over at least 2 years.
Graziani
Filippo
F
Department of Periodontology, Eastman Dental Institute, University College London, London, UK.
Laurell
Lars
L
Tonetti
Maurizio
M
Gottlow
Jan
J
Berglundh
Tord
T
D020341:Absorbable Implants; D016301:Alveolar Bone Loss / Q000601:surgery*; D000818:Animals; D001861:Bone Regeneration; D025021:Cementogenesis; D002951:Citrates; D003739:Dental Cementum / Q000502:physiology*; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D008252:Macaca fascicularis; D008567:Membranes, Artificial; D010513:Periodontal Ligament / Q000502:physiology*; D011091:Polyesters; D011138:Polytetrafluoroethylene; D012038:Regeneration / Q000502:physiology*; D014945:Wound Healing / Q000502:physiology
D002951:Citrates; C105021:Guidor; D008567:Membranes, Artificial; D011091:Polyesters; D011138:Polytetrafluoroethylene