放射性治疗对SD大鼠唾液中变形链球菌数量的影响  

Effects of radiotherapy on level fo Streptococcus mutans in saliva of SD rats

作　　者：刘江峰[1] 陈之锋[1] 高平[2] 余伟明[2] 刘小峰[2] 方海琼[1] 

机构地区：[1]广州医学院口腔医院修复科,广东广州510140 [2]广州医学院第一附属医院口腔科,广东广州510120

出　　处：《广州医学院学报》2011年第4期35-37,共3页Academic Journal of Guangzhou Medical College

基　　金：广东省自然科学基金(81510140002000002);广州市荔湾区科技计划项目(20081210079)

摘　　要：目的：通过建立动物模型，探讨放射性治疗对SD大鼠唾液中变形链球菌数量的影响。方法：选自20只雌性sD大鼠，随机分成试验组和对照组，每组各10只。经接种变形链球茵后，试验组予以15Cy／d放射剂量对双侧腮腺进行照射，连续照射30d。于放射始、30、60d以及90d时，观察大鼠唾液中变形链球茵的数量，并于放射90d时，统计患龋率及根据Keyes评分法评定大鼠患龋状况。结果：随着观察时间的延长，两组大鼠唾液中变形链球菌的数量均不断增加，但实验组各时间点变形链球菌增加数量明显高于对照；放射90d时，大鼠唾液变形链球菌的数量可达l（8．60±O．21）＊107]mL，而对照组仅为[（1．914-0．12）×107^]mL，两组间差异有统计学意义（P〈0．05）。实验组的患龋率及Keyes评分法均明显高于对照组，两组间差异有统计学意义（P〈0．05）。结论：放疗可促进SD大鼠唾液中变形链球菌的繁殖而增加其患龋的风险。Objective：To explore the effect of radiotherapy on level of Streptococcus mutans in saliva of established Sprague-Dawley （SD） rat models. Methods： Twenty female SD rats were randomized into the experimental group and the control group （n = l0 each）. The rats were inoculated with Streptococcus mutans. Thereafter, the experimental group was exposed to 15Gy/d radiation of bilateral parotid glands for 30 days. The counts of Streptococcus mutans in saliva of SD rats were record on days 1, 30, 60 and 90 of treatment. Prevalence and severity of dental caries in SD rats were evaluated according to Keyes caries scores. Results：The counts of Streptococcus mutans in both groups increased over time, but were higher in the experimental group compared with the control group at each time point. On day 90 post-radiation, the count of Streptococcus mutans was （8.60 ＋0.21 ） x 107ml in the experimental group vs （ 1.91 ~ 0.12） x 107ml in the control group, with statistical significance between the two （ P 〈 0.05 ）. The prevalence and Keyes scores of caries were also higher in the experimental group than those in the control group （ P 〈 0.05 ）. Conclusion ： Radiotherapy may stimulate growth of Streptococcus mutans in saliva and increase risk of caries in SD rats.

关 键 词：龋病 放射治疗 变形链球菌 

分 类 号：R815[医药卫生—放射医学]