Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Division of Oral Science for Health Promotion, Department of Oral Health and Welfare, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
J Oral Rehabil. 2024 Sep;51(9):1759-1769. doi: 10.1111/joor.13764. Epub 2024 Jun 5.
It remains unclear how the salivary flow and the fat content of food affect bolus formation during mastication.
We aimed to clarify: (1) how hyposalivation affects jaw-closing and hyoid-elevating muscle activities in bolus formation, and (2) if the effect of hyposalivation on muscle activity depends on the fat content of food.
Eighteen healthy male volunteers were instructed to freely ingest four test foods: Plain, Fat without seasoning, Fat with seasoning, and Soft rice crackers. Masseter and suprahyoid electromyographic activities were recorded before and 30 min after the administration of atropine sulfate, a muscarinic receptor antagonist that induces hyposalivation.
Hyposalivation extended the masticatory duration significantly in all the test foods except Fat with seasoning. Masticatory cycle time was significantly longer with vs without hyposalivation for the Soft (p = .011). Suprahyoid activity/cycle was significantly greater with vs without hyposalivation (p = .013). Masticatory cycle time was significantly longer at the late stage with vs without hyposalivation for the Soft (p < .001). Suprahyoid activity/cycle was significantly greater at the middle (p = .045) and late stages (p = .002) with vs without hyposalivation for the Soft and greater at the late stage with vs without hyposalivation for the Plain (p = .043). Changes in masticatory cycle time and suprahyoid activity/cycle for these foods had significantly positive relationship (p < .001).
Hyposalivation-induced changes in masticatory behaviours resulted from the middle and late stage suprahyoid activity. Fat content and seasoning compensate for salivary flow inhibition.
唾液流量和食物脂肪含量如何影响咀嚼过程中的食团形成仍不清楚。
我们旨在阐明：（1）流涎减少如何影响食团形成中的下颌闭合和舌骨上提肌活动；（2）流涎减少对肌肉活动的影响是否取决于食物的脂肪含量。
18 名健康男性志愿者被指示自由摄入四种测试食物：原味、无调味料脂肪、有调味料脂肪和软米饼。在硫酸阿托品（一种导致流涎减少的毒蕈碱受体拮抗剂）给药前后，记录咀嚼肌和舌骨上肌群的肌电图活动。
除了有调味料脂肪之外，流涎减少显著延长了所有测试食物的咀嚼时间。软米饼在有 vs 无流涎减少时咀嚼周期时间显著更长（p = 0.011）。有 vs 无流涎减少时，舌骨上肌群活动/周期显著更大（p = 0.013）。软米饼在有 vs 无流涎减少时咀嚼周期时间在晚期显著更长（p < 0.001）。有 vs 无流涎减少时，软米饼和原味在中（p = 0.045）和晚期（p = 0.002）舌骨上肌群活动/周期显著更大，软米饼在晚期有 vs 无流涎减少时舌骨上肌群活动/周期显著更大（p = 0.043）。这些食物的咀嚼周期时间和舌骨上肌群活动/周期的变化呈显著正相关（p < 0.001）。
流涎减少引起的咀嚼行为变化源于中晚期舌骨上肌群活动。脂肪含量和调味料可以补偿唾液流量抑制。
