Guang-wen Li ＊,Jun Wang ,Zong-ke Gao ,Zeng-qiang Zhao ,Yan Zhang ,Hui Li ,Yu-xing Wang,Dong-ping Wang ,Jing Guo,and Gang Li

1Department of Stomatology,537 Hospital of the People’s Liberation Army,BaoJi,Shaanxi 721006,China

2Department of Epidemiology,Huaxi Public Health School,Sichuan University,Chengdu 610000,China

3Department of Hyperbaric Oxygen Chamber,451 Hospital of the People’s Liberation Army,Xi’an 710000,China

4Department of Preventive Dentistry,School of Stomatology,Fourth Military Medical University,Xi’an 710032,China

ORAL epidemic diseases of exposure personnel in long-term low-dose radiation yet have rarely been studied.Referred to WHO oral health survey method and symptom grading standard,data of 341 exposure persons in long-term low-dose radiation including α particle,β particle,and γ rays,etc.,were collected from one camp in China in 2011 with cluster sampling and analyzed with Foxpro 6.0 and SPSS 16.0 software.The exposure persons worked in low-dose radiation for a long time aged between 23 and 56,whose average age were 27.1 years old.In addition,their lengths of service were from 2 to 34 years (average 7.9 years) and average exposure time was 8 hours a day each year for more than three months.Average annual radiation dose equivalent was from 1.8 to 16.5 mSv (average 7.3 mSv).Total radiation dose equivalent was from 3.8 to 425.0 mSv(average 97.3 mSv).

The survey results revealed extremely poor oral health of the exposure personnel.The recorded total rate of oral mucositis was 29.3% (100/341),which included 13.2%WHO mucositis symptom grading standard level I,9.4%level II,2.6% level III,2.6% level Ⅳ,and 1.5% other oral diseases.Viewed from locations of frequent occurrence,oral mucosal damages occurred with characteristic of multiple damage parts existing at the same time in most places of oral cavity such as buccal mucosa,lips,tongue,soft palate,alveolar ridge,and gingival,et al,of which the highest prevalence place was buccal mucosa accounting for 62%,next was lips (39%) and tongue (23%).Looking from the history of oral mucositis,it happened before enlistment occupied merely 17.7%,and most of oral mucositis on exposure persons appeared during military service.Prevalence proportions of acute caries,laryngopharyngitis,and xerostomia on exposure personnel were 35.2%,5.4%,and 34.9%,respectively.The unstimulated whole salivary flow rate (UWSFR) and stimulated whole salivary flow rate(SWSFR) were respectively 0.311 mL/min and 0.815 mL/min,between which there were statistically significant differences in salivary flow rates (P＜0.05).Among the surveyed group,pH value of salivary ranged from 5.0 to 7.1,of which means and standard deviation (6.16±0.52)was obviously lower than that of healthy people (6.74±0.36).

The investigation results indicated that a mass of oral epidemic diseases on exposure personnel in long-term lowdose radiation were rampant,which implicated long-term low-dose radiation as most dominating cause of the outbreak.Meanwhile,long-term and low-dose radiation could break the physiological balance and bring irreversible damage to healthy people.It was necessary to take more special oral health care,further enhance the individual protection awareness,strengthen the radiation monitoring and measures of radiation protection,establish perfect system of regulations,and eventually reduce radiation damage on exposure personnel significantly.