- 學位論文
Covid-19疫情期間牙科治療椅水路系統水質變化監測改善流程
The improved sterilization process to monitor the changes of the water quality in the dental delivery system during the Covid-19 pandemic
摘要
目的：Covid-19疫情期間依據感染管制措施,非必要急迫性醫療勿到醫療院所或私人牙科診所就診，牙科相關療程減少易導致牙科治療台水路(dental unit water line，DUWL)生物膜的微生物滋生。目前醫療院所及私人診所DUWL水質的監測頻率不一，不同牙科治療台廠商操作手冊使用不同的消毒方法，且微生物監測沒有統一的國際判讀標準。希望藉此研究分析如何降低DUWL水質總生菌數，建立適宜的判讀標準，減少因牙科治療過程所引起的感染。 方法：以台灣北部某地區教學醫院為研究對象，研究時間7個月。自來水源以逆滲透處理，成為過濾軟水再使用UV照射及添加5%次氯酸鈉殺菌，執行3個月1次以5%次氯酸鈉水源水路消毒，使水源餘氯保持0.5-0.8 mg/L符合自來水的餘氯要求(0.2-1 mg/L)來維持殺菌的效果。DUWL以協議廠商提供的1.41%過氧化氫作為長期持續使用的消毒劑，每個月執行1次DUWL的高濃度消毒。一般療程使用的水質則維持1:100(1.41%過氧化氫10ml:水1L)稀釋低濃度過氧化氫抑制微生物的生長。每3個月使用1000ppm次氯酸水取代1.41%過氧化氫作為衝擊消毒，防止長期使用1種消毒劑造成微生物耐受性增加。水樣採集包含牙科軟水及DUWL水源入口、漱口水和手機四大類別，手機水樣分開採集，採用塗抹平板法(Spread-plate method)進行細菌的培養，結果單位體積1ml含菌落群數表示(CFU/mL)進行數據分析。 結果: 本實驗比較不同手機間總生菌數，第2台治療椅高速手機與三通管及高速手機與慢速手機以統計方法t-test分析，P值皆<0.05，高速手機降速空氣回吸會最易導致水路汙染，有統計上的意義。改善前和4個改善流程總生菌數的比較，one-way ANOVA分析第1.2.3台治療椅手機端、漱口水端及水源端P值<0.05，改善流程成功使DUWL生菌數持續獲得控制有統計上的意義。分析看診人數和DUWL生菌數的關係，以統計方法two-way ANOVA分析是沒有統計上的意義，DUWL生菌數的多少在於消毒流程確實執行而非看診人數。 結論:不同手機間分析，證明高速手機降速空氣回吸最易導致水路汙染，就算是新型的治療台手機頭內建逆止閥，仍難以完全避免病患口腔微生物回吸，所以病人治療結束確實執行20-30秒的放流。依據改善流程擬定標準操作流程，每3個月使用1000ppm次氯酸水取代1.41%過氧化氫作為衝擊消毒，水源餘氯保持0.5-0.8 mg/L，使DUWL生菌數持續獲得控制。本研究提出監測前端水路的重要性，設計既不造成現場人員負擔且最有效的消毒方法，依據研究結果建議設定監測頻率3個月1次，判讀標準<5 CFU/ml，優化水質醫病雙贏。
並列摘要
Purpose: The reduce numbers of dental visits during the Covid-19 pandemic, will change the breed of microbes on the biofilm in the dental unit water line (DUWL).There is no unified international standard for disinfection method to monitor the DUWL water quality.We establish an appropriate standard of sterilization process to monitor the water quality and microbe colonies of DUWL. Methods: A teaching hospital in a certain area of northern Taiwan was taken as the research object, and the research time was 7 months. The tap water source is treated with automatic backwashing of laminated filters, etc., and becomes filtered soft water, then UV irradiation and 5% sodium hypochlorite are added for sterilization, and the water source waterway is disinfected with 5% sodium hypochlorite once every 3 months to keep the residual chlorine in the water source at 0.5-0.8 mg /L meets the residual chlorine requirements of tap water (0.2-1 mg/L) to maintain the sterilization effect. DUWL uses 1.41% hydrogen peroxide provided by the agreement manufacturer as a long-term continuous use disinfectant, and performs high-concentration disinfection of DUWL once a month. The water quality used in the general course of treatment is maintained at 1:100 (10ml 1.41% hydrogen peroxide: 1L water) to dilute low-concentration hydrogen peroxide to inhibit the growth of microorganisms. Use 1000ppm hypochlorous acid water every 3 months to replace 1.41% hydrogen peroxide as impact disinfection to prevent the increase of microbial tolerance caused by long-term use of one disinfectant. The water sample collection includes four categories: dental soft water and DUWL water inlet, mouthwash and handpieces. The handpieces water samples are collected separately, and the spread-plate method is used for bacterial culture. The result is expressed as the number of colonies per unit volume 1ml ( CFU/mL) for data analysis. Results: In this experiment, the total bacterial counts between different handpieces were compared. The high-speed handpieces and the three-way pipe of the second dental unit, and the high-speed handpieces and the slow handpieces were analyzed by statistical method t-test, and the P values were all <0.05. on the meaning. The comparison of the total number of bacteria before the improvement and the four improvement processes, the one-way ANOVA analysis of the 1.2.3 dental unit handpieces end, mouthwash end and water source end P values are all <0.05, the improvement process is statistically significant, Only the second chair water source was not statistically significant. Analysis of the relationship between the number of visits and the number of bacteria in DUWL, the statistical method two-way ANOVA analysis was not statistically significant. Conclusion: The analysis of different handpieces proves that the air sucking back effect of the high speed handpieces will cause water pollution. Even using a new handpiece with a built in checkiy valve, the dismal effect persisted. Replace the 1.41% hydrogen peroxide with 1000 ppm hypochloride acid water every 3 months and keep the residual chlorine in the water source with a concentration of 0.5-0.8 mg/L in order to control the bacteria count in DUWL continuously. The actual implementation of the improved DUWL disinfection processes is the independent factor rather than the number of dental visits. The frequency of monitoring water quality every 3 months and the interpretation standard for microorganism with less than 5 CFU/mL are mandatory.