Topical application of statin affects bone healing around implants.
OBJECTIVE
3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are widely used for hyperlipidemia. Recent studies demonstrate that statins stimulate bone morphogenetic protein-2 expression and lead to bone formation. The aim of this study was to evaluate whether the topical application of statin enhances the osteogenesis around a titanium implant.


METHODS
Ten-week-old female rats received pure titanium rods in both tibiae with or without fluvastatin. Propylene glycol alginate (PGA) was used as a carrier. The rats were divided into five groups: implant-only group, implant with PGA group, low-dose group [implant+PGA containing 3 microg of fluvastatin (FS)], medium-dose group (15 microg of FS), and high-dose group (75 microg of FS). The animals were sacrificed at 1 and 2 weeks after implantation. Peri-implant bone formation was assessed by histomorphometric procedures, i.e., measuring the bone-implant contact (BIC) and peri-implant bone volume (BV). A mechanical push-out test was also performed to evaluate the implant fixation strength. Statistical differences among the groups were determined by ANOVA and P < 0.05 was considered significant.


RESULTS
At week 1, there was no significant difference in BIC among the groups, however, BV and the push-out strength were significantly higher in the high-dose group than in the implant-only group. At week 2, BIC and BV had significantly increased in the high-dose group in comparison with the non-statin groups. The fluvastatin-treatment group showed a significant increase in push-out strength compared with the non-statin groups.


CONCLUSIONS
Our histomorphometrical and mechanical evaluations revealed the positive effect of topically applied fluvastatin on the bone around the implant.
Moriyama
Yasuko
Y
Division of Oral Rehabilitation, Faculty of Dental Science Higashi-ku, Fukuoka, Japan.
Ayukawa
Yasunori
Y
Ogino
Yoichiro
Y
Atsuta
Ikiru
I
Koyano
Kiyoshi
K
D000287:Administration, Topical; D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects*; D015921:Dental Implants; D004305:Dose-Response Relationship, Drug; D005229:Fatty Acids, Monounsaturated / Q000008:administration & dosage*; D005260:Female; D000077340:Fluvastatin; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage*; D007211:Indoles / Q000008:administration & dosage*; D016348:Osseointegration / Q000187:drug effects*; D010012:Osteogenesis / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D018709:Statistics, Nonparametric; D013314:Stress, Mechanical; D013977:Tibia / Q000187:drug effects / Q000601:surgery; D014025:Titanium; D016474:Weight-Bearing; D014945:Wound Healing / Q000187:drug effects
D015921:Dental Implants; D005229:Fatty Acids, Monounsaturated; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D007211:Indoles; D000077340:Fluvastatin; D014025:Titanium