本研究之目的為測試咀嚼波爾木糖醇／山梨醇口香糖是否會影響國人口腔內牙菌斑堆積量及牙茵斑內突變形鏈球菌數目。本實驗篩選26位年齡介於21至31歲之成年人。受檢者隨機分成實驗組及對照組，每組13人。實驗組受檢者每天咀嚼木糖醇／山梨醇口香糖五次，每次一片，為期兩過。在咀嚼前及兩週後，收集全部牙齒之牙齦上牙菌斑，並立即稱重。牙菌斑經十倍數稀釋後，種在MSB及BHI培養基上，以計算突變形鏈球菌數目及總菌數目。對照組在實驗期間不可咀嚼任何廠牌口香糖。結果顯示實驗組受試者在咀嚼木糖醇無糖口香糖兩週後，牙菌斑堆積量明顯的減少35.8%(p<0.05)，突變形鏈球菌數量亦顯著的減少32.5%(p<0.05)。對照組在兩週前及後之牙齒斑堆積量與突變形鏈球菌數目皆無顯著的改變。因牙菌斑堆積量及牙菌斑內突變形鏈球菌數目是引起齲齒之危險因子，由本研究之結果可推論：長期咀嚼木糖醇／山梨醇口香糖有降低齲齒形成之功效。

Effects of xylitol/sorbitol chewing gum on plaque accumulation and S. mutans counts were studied by examining in heal thy adult volunteers. Twenty-six healthy volunteers aged between 21 and 31 years old were randomly assigned to either the experimental or control group. Subjects in the experimental group chewed 5 sticks of xylitol/sorbitol chewing gum daily for 2-week while those in the control group did not chew any gum during the same period. Prior to the beginning and at the end of the gum trial, plaque on all teeth of the subjects was collected and weighted. Results indicated that the group that chewed xylitol chewing gum for 2 weeks showed significantly decreases in both plaque accumulation (35.8%; p<0.05) and S. mutans counts (32.5%; p<0.05) while those in the control group showed no significant changes. The results thus indicate that chewing xylitol/sobital chewing gum could decrease the likelihood of dental caries.