Effect of cyclosporin A on the mineral apposition rate of cementum and dentin in growing rats.
BACKGROUND
Since there is no direct information to verify whether cyclosporin A (CsA) can affect the mineralization of dental hard tissue, the formation of dentin and cementum in growing rats was recorded by labeling the mineral phase of these tissues with fluorochrome marker in this study.


METHODS
After the extraction of the right maxillary molars, 30 male 3-week-old Sprague-Dawley rats were assigned to two groups. Following a 2-week healing period, the experimental rats received 30 mg/kg CsA daily for 7 weeks, while the control rats received only mineral oil. The fluorescent markers, calcein and alizarin red, were given on alternate weeks for 7 weeks. At the end of study, the mandibles were obtained and undemineralized sections were processed. Serial sections, 8 microm thick, were cut for the entire distal roots of the first molars. Five central sections were selected to determine the mineral apposition of cellular cementum and dentin at the apex and middle of root, respectively.


RESULTS
The apposition rates of apical cellular cementum were significantly influenced by CsA therapy, occlusal function, and observation duration. However, the dentin apposition rates were significantly influenced by the observation intervals only.


CONCLUSIONS
In this study, CsA therapy and occlusal function significantly influenced the apposition rates of apical cementum, but not the rates of mid-root dentin. Our hypothesis that CsA can induce oral hard tissue alterations, as well as gingival overgrowth, is demonstrated.
Shen
E-Chih
EC
Department of Periodontology, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan. dentalab@tpts5.seed.net.tw
Fu
Earl
E
Gau
Ching-Hwa
CH
Hsieh
Yao-Dung
YD
Chiang
Cheng-Yang
CY
D000818:Animals; D016572:Cyclosporine / Q000494:pharmacology*; D003739:Dental Cementum / Q000187:drug effects* / Q000502:physiology; D003766:Dental Occlusion; D003804:Dentin / Q000187:drug effects* / Q000502:physiology; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D007166:Immunosuppressive Agents; D016572:Cyclosporine