[A comparison of the effects of 180kv X-ray radiation and cobalt-60 radiation on the jaws of the guinea pigs]
OBJECTIVE: Study of the effects of 180kv x-ray and cobalt-60 radiation on jaws and enhance the understanding of pathology of osteroradionecrosis of jaws(ORNJ).METHODS: 128 guinea pigs were grouped according to different irradiation sources and doses.Fractioned radiation from both sources was delivered in right mandible.The teeth extractions were conducted one week prior to radiation and 1,3,5 months after radiation respectively.Following radiation,the guinea pigs were examined by gross observation, x-ray film and histopathological examination at regular interval. RESULTS: Bone resorption occured within 1 month after irradiation as result of osteoblast inhibition and osteoclast activation.From 2 to 4 month afterwards,the number of osteocytes reduced and pyknosis, empty lacunae as well as obliteration of small vessels in periodontal membrane were commonly seen.The teeth extractions conducted at 3 months,5 months after radiation lead to ORNJ in 7 amimals (14.6%).CONCLUSION: 180kv x-ray radiation was far more damaging to jaws than cobalt-60 radiation.The dental extraction is an important factor inducint the development of ORNJ.
Xie
X T
XT
Department of Oral and Maxillofacial Surgery,School of Stomatology,Shanghai Second Medical University. Shanghai 200011, Chain.
Qiu
W L
WL
Yuan
W H
WH
Wang
Z H
ZH