ความสัมพันธ์ระหว่างขนาดของรอยเชื่อมต่อบริเวณตัวหลักบนตัวรากเทียมกับการแทรกซึมของเชื้อแบคทีเรีย / ศันสนีย์ เทพชาตรี = The relationship between size of gap at implant-abutment interface and bacterial penetration / Sansanee Thepchatri
The purpose of this study was to evaluate the relationship between size of gap at implant-abutment interface and bacterial penetration. Three types of bacteria: Fusobacterium nucleatum, Porphyromonas gingivalis and Escherichia coli were selected. Three ranges of gap at implant-abutment interface were set up. The first range was 10.001-20.000 micrometer, the second range was 1.001-10.000 micrometer and the third range was 0.001-1.000 micrometer. Thirty implant and implant abutment specimens were used for each condition. The experiments were done by submerging the specimens in inoculated broth, the viscosity of which was controlled by optical absorption value which was set to the range of minimum and maximum value of gingival fluid viscosity. The specimens were submerged for 48 hours and were then subjected to the bacterial penetration test by allowing an endodontic paper point to contact the internal part of each implant for about 60 seconds, then transferring the paper point into each experimental tube andcounting the amount of the positive experimental tube as the positive result. The numbers of positive results in F. nucleatum were 7,8 and 0 in the first, second and third gap range respectively, while those in P. gingivalis were 5 and 10 in the first and second gap range, but no growth was seen in the third one. In E. coli, all samples of the first and second gap ranges were found to be positive; however, only 18 positive samples were seen in the third one. The influence of gap size to the bacterial penetrating capability was analyzed by Chi-square test and a significant difference was demonstrated in all the bacteria used in this study (p<0.01). As a conclusion, the variation in size of gap at implant-abutment interface the bacterial penetration.