[Radiological and histopathological changes of the periapical lesions induced by lipopolysaccharide in rats].
OBJECTIVE
To investigate histological and X-ray dynamic changes of periapical lesions induced by lipopolysaccharide(LPS) in rats.


METHODS
Experimental periapical periodontitis models in 24 Wistar rats were established by exposing pulps, placing absorbent cotton with LPS, and exposing in the oral environment. Four experimental animals were sacrificed on the day 0,3,7,14,21, and 35, respectively. Root apical radiographs and tissue sections were taken in all the teeth combined with bone from sacrificed animals. Periapical histological changes and roentgenograms were observed. The results were analyzed statistically by F test and Student's t test with SPSS12.0 software package.


RESULTS
On the day 3, infiltration of inflammatory cells in the periapical tissue was observed. Acute inflammatory states, severe inflammatory states and chronic inflammatory states were detected at 1 week, 2-week and 3-week,respectively. Cementum hyperplasia was observed at 5-week. Increasing periapical radiolucent areas were observed after 1 week. Intervention, there were significant differences in the periapical lesion areas at the different period time(P<0.01).


CONCLUSIONS
The procedures that induced periapical lesions in animal model established by exposing pulps of molar teeth,placing absorbent cotton with LPS, and exposing to the oral environment is similar to human natural progress of the same disease and has a shorter time duration. It is an ideal research model for periapical periodontitis.
Wang
Qing-shan
QS
Department of Endodontics, College of Stomatology, Binzhou Medical College, Binzhou 256603, Shandong Province, China. wqsyahao@yahoo.com.cn
Gao
Yan
Y
Rong
Li
L
Wang
Ai-qin
AQ
D016301:Alveolar Bone Loss; D000818:Animals; D004195:Disease Models, Animal; D008070:Lipopolysaccharides; D010485:Periapical Periodontitis; D051381:Rats; D017208:Rats, Wistar
D008070:Lipopolysaccharides