Intrusion of teeth with class III furcation: a clinical, histologic and histometric study in dogs.
OBJECTIVE
To assess orthodontic intrusion effects on periodontal tissues in dogs' pre-molars with class III furcations treated with open flap debridement (OFD) or with guided tissue regeneration (GTR) associated to bone autograft (BA).


METHODS
Class III furcations were created in the pre-molars of seven mongrel dogs. After 75 days, teeth were randomly treated with OFD or GTR/BA. After 1 month, metallic crowns were assembled on pre-molars and connected apically to mini-implants by nickel-titanium springs. Teeth were randomly assigned to orthodontic intrusion (OFD+I and GTR/BA+I) groups or no movement (OFD and GTR/BA) groups. Dogs were sacrificed after 3 months of movement and 1 month retention.


RESULTS
All class III furcations were closed or reduced to class II or I in the intrusion groups, while 50% of the lesions in non-moved teeth remained unchanged. Intruded teeth presented higher probing depth and lower gingival marginal level than non-moved teeth (p<0.01). Clinical attachment gain was reduced in the intrusion groups by the end of retention (p<0.05). OFD+I presented smaller soft tissue area and larger bone tissue area than other groups (p<0.05).


CONCLUSIONS
Orthodontic intrusion with anchorage via mini-implants improved the healing of class III furcation defects after OFD in dogs. GTR/BA impaired those results.
da Silva
Vanessa C
VC
Department of Periodontology, School of Dentistry at Araraquara, UNESP - São Paulo State University, SP, Brazil.
Cirelli
Carolina C
CC
Ribeiro
Fernando S
FS
Leite
Fábio R M
FR
Benatti Neto
Carlos
C
Marcantonio
Rosemary A C
RA
Cirelli
Joni A
JA
D000539:Alveolar Process / Q000473:pathology / Q000503:physiopathology; D000818:Animals; D001641:Bicuspid / Q000503:physiopathology / Q000601:surgery*; D016025:Bone Transplantation / Q000379:methods*; D003646:Debridement; D003739:Dental Cementum / Q000473:pathology / Q000503:physiopathology; D004285:Dogs; D017823:Furcation Defects / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D005889:Gingival Recession / Q000503:physiopathology / Q000601:surgery; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation; D009967:Orthodontic Appliances; D018704:Orthodontic Retainers; D009969:Orthodontic Wires; D017622:Periodontal Attachment Loss / Q000503:physiopathology / Q000601:surgery; D010513:Periodontal Ligament / Q000473:pathology / Q000503:physiopathology; D010514:Periodontal Pocket / Q000503:physiopathology / Q000601:surgery; D011897:Random Allocation; D013314:Stress, Mechanical; D013524:Surgical Flaps; D013997:Time Factors; D014087:Tooth Movement Techniques / Q000295:instrumentation / Q000379:methods*; D014182:Transplantation, Autologous; D016896:Treatment Outcome