The randomized trial for Effect of oral health care on the recovery from surgery in elderly patients

2004 Fiscal Year Final Research Report Summary

• Project/Area Number: 14571943
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 矯正・小児・社会系歯学
• Research Institution: Niigata University
• Principal Investigator: YOSHIHARA Akihiro Niigata University, Graduate school of Medical and Dental Sciences, Associate Professor, 大学院・医歯学総合研究科, 助教授 (50201033)
• Co-Investigator(Kenkyū-buntansha): SATO Masako Kitasato Junior College of Health and Hygienic Scienses, Assistant, 保健衛生専門学院・看護科, 助手 ; MURATA Takatosi Kyusyu Dental College, Assistant, 歯学部, 助手 (10313529) ; MIYAZAKI Hideo Niigata University, Graduate school of Medical and Dental Sciences, Professor, 大学院・医歯学総合研究科, 教授 (00157629)
• Project Period (FY): 2002 – 2004
• Keywords: Postoperative oral care / Elderly people / Respiratory dysfunction

Research Abstract

The purpose of the present study was to clarify the effectiveness of postoperative oral care, including toothbrushing, denture cleaning and tongue cleaning following digestive tract surgery.
The subjects were 30 consenting elderly patients aged between 60 and 98 years (mean, 76.9±7.8 years) who underwent digestive tract surgery. Using a systematic sampling method, subjects were divided into two groups : an intervention group, and a control group. In the intervention group, the following oral care was provided daily over a five-minute period between 7 and 8 in the morning : gargling with povidone iodine, tooth brushing, denture cleaning using a special brush, and tongue cleaning using a tongue brush. In the control group, the subjects only gargled with povidone iodine. The number of remaining teeth, denture usage, sensation of dry mouth, dental calculus deposition, tooth mobility, and volatile sulfur compounds were compared between the intervention and control groups. Then, changes in vo latile sulfur compounds, pulmonary sounds, pharyngeal bacteria and fever from the time of operation to five days after surgery were compared between the intervention and control groups.
The incidence of abnormal pulmonary sounds for the intervention group increased from 6.6 to 13.0% (an increase of 6.4%), while that for the control group increased from 0 to 26.6% (p<0.05, Fisher's direct probability test). The average number of bacterial species per subjects for the control group was 3.64±1.34 preoperatively and 3.50±1.74 postoperatively, whereas that for the intervention group was 3.08±0.95 preoperatively and 2.62±0.65 postoperatively. In the intervention group, there was a significant decrease in the number of bacterial species (p<0.05,t-test). The average degree of change (ng/10ml) in hydrogen sulfide levels from before surgery to five days after surgery for the intervention and control groups was -2.93±8.08 and 0.81±4.86,respectively ; for methyl mercaptan, -1.10±2.30 and 0.40±1.72,respectively ; for dimethyl sulfide -0.36±1.30 and 0.16±1.60,respectively. When compared to the control group, the level of each volatile sulfur compound markedly decreased for the intervention group, and there was a statistically significant difference in methyl mercaptan (p<0.001,t-test).
Since anaerobic bacteria are involved in the production of volatile sulphur compounds in the oral cavity, the volatile sulphur compounds concentration is believed to reflect the number of bacteria in the mouth. The findings in the study clarify that postoperative oral care in elderly patients undergoing digestive tract surgery lowers the number of bacterial species found in the oral cavity and alleviates respiratory dysfunction.