Development of a root canal treatment model in the rat

Abstract

Root canal treatment is performed to treat apical periodontitis, and various procedures and techniques are currently used. Although animal models have been used in the developmental research of root canal treatment, little of this research has used small animals such as rats, because of their small size. In this study, root canal treatment was performed on the rat mandibular first molar, which had four root canals, using a microscope, and the therapeutic effect was evaluated bacteriologically, radiologically and histopathologically. By performing root canal treatment, the level of bacteria in the mesial root of the treated teeth was reduced by 75% compared with the control. Additionally, the volume of the periapical lesions of the treated teeth as measured by micro-computed tomography decreased significantly 2 weeks after the root canal treatment when compared with the control. Histological evidence of healing was observed in the treatment group 8 weeks after root canal treatment. These results suggest that a root canal treatment model using rats can be used in developmental research for novel methods of root canal treatment.

Dentinogenic effects of extracted dentin matrix components digested with matrix metalloproteinases

“…Pulp-capped teeth were removed en bloc with surrounding maxillary bone and immersed in the same fixative for an additional 24 h. The induced tertiary dentin (n = 6 in each group) was analysed by using a micro-CT scanner (R_mCT2, Rigaku, Tokyo, Japan) at settings of 90 kV and 160 µA with a scanning resolution of 20 μm intervals in individual image. After scanning, the area of induced tertiary dentin of each specimen was quantitatively analysed by using three-dimensional reconstruction images for bone (TRI/3D-BON; Ratoc System Engineering, Tokyo, Japan) with reference to previous report 67 , 68 . After confirming the consistency between micro-CT and histological images, image analysis was performed.…”

Influence of apical enlargement on the repair of apical periodontitis in rats

“…In a recent study performing root canal treatment in all roots of rat molars using a clinical microscope (Yoneda et al . ), it was not possible to obtain healing of the distal canal lesions. So far, only the mesial canal of the mandibular molar was viable for treatment.…”

“…This might have influenced the relative difficulty in the total elimination of infection, with consequent persistence of inflammatory cells in the periapical region. In a recent study performing root canal treatment in all roots of rat molars using a clinical microscope (Yoneda et al 2017), it was not possible to obtain healing of the distal canal lesions. So far, only the mesial canal of the mandibular molar was viable for treatment.…”

Endoscopic near‐infrared dental imaging with indocyanine green: a pilot study

“…1 A recent publication reported to develop novel root canal treatments using rats as model animals. 43 Here, we demonstrate that ICG-enhanced NIR fluorescence method (650-950 nm) can be used to image unerupted molars. The results provide proof-of-concept evidence for the development of ICG-based NIR dental imaging in the diagnosis of tooth eruption using rat pups.…”

“…In particular, the first mandibular molars of rats or mice have been widely used in studying odontogenesis, and the findings have been successfully applied to the relevant human dental research . A recent publication reported to develop novel root canal treatments using rats as model animals . Here, we demonstrate that ICG‐enhanced NIR fluorescence method (650–950 nm) can be used to image unerupted molars.…”