A histochemical study of the regeneration process after injury by pulsed Nd:YAG laser irradiation of root canals.
Histological changes of rat dental pulp cells were followed after injury. The regeneration process after 3, 6 and 10 days was monitored. Mandibular incisors were irradiated with a pulsed Nd:YAG laser at 2 W and 20 pulses per sec (pps) for 5 sec and the pulp was examined histologically and immunohistochemically for TGF-beta1. Eruption of the developing tooth was disturbed for a short period only. Rapid formation of osteodentin was observed. After 3 days, a zone of fibrodentin matrix as well as newly formed vessels were found. Afterwards, regenerative dentin formation was observed accompanied by the formation of a layer of odontoblast-like cells in the damaged area. Immunohistochemical staining of TGF-beta1 showed that positivity was present in small tissue areas beneath the mantle dentin, the zone of fibrodentin matrix and odontoblast-like cells. These results indicate that pulsed Nd:YAG laser irradiation of rat incisor pulp induces formation of osteodentin, and TGF-beta1 plays a role during regeneration.
Murakami
Yoshiko
Y
Department of Endodontics, Showa University School of Dentistry, Tokyo, Japan. mumingg@aol.com
Unno
Arine
A
Kimura
Yuichi
Y
Okano
Tomohiro
T
Hossain
Mozammal
M
Nakamura
Yukio
Y
Matsumoto
Koukichi
K
D000818:Animals; D004396:Coloring Agents; D003782:Dental Pulp / Q000473:pathology / Q000502:physiology / Q000528:radiation effects; D003786:Dental Pulp Cavity / Q000293:injuries* / Q000473:pathology / Q000502:physiology*; D003804:Dentin / Q000378:metabolism; D007150:Immunohistochemistry; D007180:Incisor / Q000293:injuries / Q000473:pathology / Q000502:physiology; D007834:Lasers; D008297:Male; D009804:Odontoblasts / Q000502:physiology; D011833:Radiation Injuries, Experimental / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar; D012038:Regeneration / Q000502:physiology*; D014078:Tooth Eruption / Q000502:physiology
D004396:Coloring Agents