title: Inhibition of tooth eruption in the rat by a bisphosphonate.
abstract: Studies of osteopetrotic rodents suggest that localized alveolar bone resorption must occur if the tooth is to erupt. To test this hypothesis directly, we injected postnatal rats with pamidronate, a bisphosphonate that reduces bone resorption by osteoclasts. The results of these experiments demonstrate that this bisphosphonate inhibits the time of tooth eruption of both rat molars and incisors. Pamidronate does not inhibit the gene expression of the putative tooth eruption molecules, colony-stimulating factor-1 and c-fos, both of which are expressed in the dental follicle, the tissue that is required for eruption to occur. Pamidronate does increase the size of the osteoclasts, including an increase in the number of nuclei, suggesting that the precursor mononuclear cells can still fuse to form osteoclasts despite the reduced ability of the osteoclasts to resorb bone. Thus, we report the discovery of an agent that inhibits tooth eruption and also show that tooth eruption requires alveolar bone resorption.
authors.affiliation: Department of Veterinary Anatomy and Cell Biology, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803-8408, USA.
authors.forename: R L
authors.initials: RL
authors.lastname: Grier
authors.forename: G E
authors.initials: GE
authors.lastname: Wise
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis; D000539:Alveolar Process / Q000187:drug effects / Q000473:pathology; D000818:Animals; D000831:Animals, Newborn; D015415:Biomarkers / Q000032:analysis; D001862:Bone Resorption / Q000503:physiopathology; D002452:Cell Count; D002467:Cell Nucleus / Q000187:drug effects; D048429:Cell Size / Q000187:drug effects; D004396:Coloring Agents; D003795:Dental Sac / Q000187:drug effects / Q000378:metabolism; D004164:Diphosphonates / Q000008:administration & dosage / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D007180:Incisor / Q000187:drug effects; D007279:Injections, Subcutaneous; D007527:Isoenzymes / Q000032:analysis; D016173:Macrophage Colony-Stimulating Factor / Q000037:antagonists & inhibitors / Q000235:genetics; D008854:Microscopy, Electron; D008963:Molar / Q000187:drug effects; D009000:Monocytes / Q000187:drug effects; D010010:Osteoclasts / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D000077268:Pamidronate; D016760:Proto-Oncogene Proteins c-fos / Q000037:antagonists & inhibitors / Q000235:genetics; D012313:RNA / Q000032:analysis / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D000071681:Tartrate-Resistant Acid Phosphatase; D014078:Tooth Eruption / Q000187:drug effects*
chemical_list: D015415:Biomarkers; D004396:Coloring Agents; D004164:Diphosphonates; D007527:Isoenzymes; D016760:Proto-Oncogene Proteins c-fos; D012313:RNA; D016173:Macrophage Colony-Stimulating Factor; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D000077268:Pamidronate