Effects of topical administration of clodronate on alveolar bone resorption in rats with experimental periodontitis.
BACKGROUND
We examined whether topical administration of a bisphosphonate clodronate could prevent alveolar bone loss in rats with experimental periodontitis.


METHODS
On day 0, elastic rings were placed around the cervix of the right and left maxillary first molars (M1) to induce inflammatory periodontitis. Fifty microl of clodronate solution at a concentration of either 0 (0.9% NaCl), 20, 40, or 60 mM was injected into the subperiosteal palatal area adjacent to the interdental area between M1 and M2 on either the left or right (experimental) side on days 0, 2, 4, and 6. The contralateral side served as a control and received 0.9% NaCl solution without clodronate. The animals were sacrificed on day 7.


RESULTS
Histological examination and determination of bone mineral density in the interdental alveolar bone area between M1 and M2 revealed that placement of an elastic ring caused severe vertical and horizontal bone resorption on the control side, while the topical administration of clodronate significantly prevented such alveolar bone loss. The number of osteoclasts on the experimental side was decreased compared with the control side. Furthermore, many of the osteoclasts on the experimental side were detached from the surface of the alveolar bone and had degenerated appearances, such as rounded shapes and a loss of polarity.


CONCLUSIONS
These results suggest that topical administration of clodronate may be effective in preventing osteoclastic bone resorption in periodontitis.
Mitsuta
T
T
Department of Oral Rehabilitation and Materials Science, Tohoku University Graduate School of Dentistry, Sendai, Japan.
Horiuchi
H
H
Shinoda
H
H
D000135:Acid Phosphatase / Q000032:analysis; D000287:Administration, Topical; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000473:pathology / Q000517:prevention & control*; D000704:Analysis of Variance; D000818:Animals; D000963:Antimetabolites / Q000008:administration & dosage / Q000627:therapeutic use*; D001391:Azo Compounds; D015415:Biomarkers / Q000032:analysis; D015519:Bone Density / Q000187:drug effects; D001862:Bone Resorption / Q000000981:diagnostic imaging / Q000473:pathology / Q000517:prevention & control; D002452:Cell Count; D004002:Clodronic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D004396:Coloring Agents; D004195:Disease Models, Animal; D004801:Eosine Yellowish-(YS); D005456:Fluorescent Dyes; D007267:Injections; D007527:Isoenzymes / Q000032:analysis; D008297:Male; D008439:Maxillary Diseases / Q000000981:diagnostic imaging / Q000473:pathology / Q000517:prevention & control; D008739:Methyl Green; D008963:Molar; D010010:Osteoclasts / Q000473:pathology; D010518:Periodontitis / Q000150:complications* / Q000188:drug therapy; D011859:Radiography; D051381:Rats; D017208:Rats, Wistar; D013223:Statistics as Topic; D000071681:Tartrate-Resistant Acid Phosphatase
D000963:Antimetabolites; D001391:Azo Compounds; D015415:Biomarkers; D004396:Coloring Agents; D005456:Fluorescent Dyes; D007527:Isoenzymes; C017768:trichrome stain; D004002:Clodronic Acid; D008739:Methyl Green; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D004801:Eosine Yellowish-(YS)