[Efficacy of systemic administration of oxytocin on implant osseointegration in osteoporotic rats].
OBJECTIVE
This study investigated the effects of systemic administration of oxytocin (OT) in osteoporotic rats on implant osseointegration.


METHODS
Twenty rats were randomly assigned to the control and experimental groups. Initially, the rats underwent bilateral ovariectomy. After 12 weeks, an osteoporosis model was established. Each rat received an implant at the distal and middle femoral metaphysis. Simultaneously, systemic administration was conducted with one group receiving subcutaneous injection of OT (1 mg·kg⁻¹ per day), whereas the other group received placebo injection. After treatment for 4 weeks, another surgery was conducted to remove the thigh bones from the rats containing the implants for an eight-week observation. With the employment of micro-CT, histological observation and push-out test, osseointegration was evaluated. While the rats received thigh-bone removal surgery, another surgery was conducted to remove the tibia metaphysis from the rats of both groups to perform histological observation and micro-CT inspection.


RESULTS
The trabecular bone of tibial samples was intensive and formed woven mesh structure in the experimental group compared with the control group. In the experimental group, the relative bone volume/tissue volume surrounding the implant, the bone contact ratio, and the maximum push-out force of the implant were 0.35%±0.06%, 67.25%±9.06%, and (70.32±10.91) N, respectively, the corresponding values were 0.11%±0.02%, 43.25%±7.01% and (21.65±4.36) N in the control group, and the experimental group increased significantly compared with the control group (P<0.05).


CONCLUSIONS
Systemic administration of OT cannot only antagonize the negative effects of osteoporosis but can also promote implant healing and osseointegration of pure titanium implants.
Dept. of Stomatology, The People's Hospital of Zhengzhou University, Zhengzhou 450003, China.
Wang
W
Maiquan
Dept. of Stomatology, The People's Hospital of Zhengzhou University, Zhengzhou 450003, China.
Peng
P
Liwei
State Key Laboratory of Oral Diseases, Dept. of Orthognathic and Temporomandibular Joint Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
Li
L
Yunfeng
D000818:Animals; D015921:Dental Implants; D005260:Female; D005269:Femur; D006801:Humans; D016348:Osseointegration; D010024:Osteoporosis; D010052:Ovariectomy; D010121:Oxytocin; D019736:Prostheses and Implants; D051381:Rats; D017207:Rats, Sprague-Dawley; D013977:Tibia; D055114:X-Ray Microtomography
D015921:Dental Implants; D010121:Oxytocin
dental implants; osseointegration; osteoporosis; oxytocin