A mouse model of inflammatory root resorption induced by pulpal infection.
OBJECTIVE
The present study was undertaken to determine the frequency and extent of apical root resorption associated with induced periradicular lesions in mice.


METHODS
Bone and root resorption was quantified by using two- and three-dimensional micro-computed tomography (mu-CT) in the lower first molars of mice subjected to pulp exposure and infection.


RESULTS
mu-CT measurements showed significant apical resorption in exposed and infected teeth, resulting in an average distal root shortening of 12.7% (P <.001 vs unexposed). These findings were confirmed with three-dimensional reconstituted images that showed thinning and shortening of the distal root. Tartrate-resistant acid phosphatase clastic cells were associated with resorption lacunae on the cementum of root apices, as well as on bone at the periphery of the periradicular lesions. Brown and Brenn staining showed the presence of bacteria in dentinal tubules adjacent to resorbed cementum.


CONCLUSIONS
Apical root resorption is a prominent and consistent finding associated with periradicular infection in the mouse. This species represents a convenient model for studying the pathogenesis of inflammatory root resorption in vivo.
Balto
Khaled
K
Department of Cytokine Biology, Forsyth Institute, Boston, Mass 02115, USA.
White
Robert
R
Mueller
Ralph
R
Stashenko
Philip
P
D000135:Acid Phosphatase / Q000032:analysis; D000818:Animals; D015415:Biomarkers / Q000032:analysis; D001862:Bone Resorption / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D004396:Coloring Agents; D003739:Dental Cementum / Q000382:microbiology / Q000473:pathology; D003788:Dental Pulp Diseases / Q000150:complications* / Q000382:microbiology; D003789:Dental Pulp Exposure / Q000150:complications / Q000382:microbiology; D003804:Dentin / Q000382:microbiology; D004195:Disease Models, Animal; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional; D007527:Isoenzymes / Q000032:analysis; D008297:Male; D008336:Mandibular Diseases / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D008963:Molar; D010483:Periapical Diseases / Q000000981:diagnostic imaging / Q000209:etiology; D012044:Regression Analysis; D012391:Root Resorption / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D013223:Statistics as Topic; D000071681:Tartrate-Resistant Acid Phosphatase; D014057:Tomography, X-Ray Computed / Q000379:methods; D019227:Tooth Apex / Q000000981:diagnostic imaging / Q000473:pathology; D014092:Tooth Root / Q000000981:diagnostic imaging
D015415:Biomarkers; D004396:Coloring Agents; D007527:Isoenzymes; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase