Kamiya Kazunobu, Narita Noriyuki, Iwaki Sunao
Department of Removable Prosthodontics, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
Automotive Human Factors Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 6, Ibaraki, Japan.
PLoS One. 2016 Jun 30;11(6):e0158070. doi: 10.1371/journal.pone.0158070. eCollection 2016.
The purpose of this study was to elucidate the effects of wearing a denture on prefrontal activity during chewing performance. We specifically examined that activity in 12 elderly edentulous subjects [63.1±6.1 years old (mean ± SD)] and 12 young healthy controls (22.1±2.3 years old) using functional near-infrared spectroscopy (fNIRS) in order to evaluate the quality of prefrontal functionality during chewing performance under the conditions of wearing a denture and tooth loss, and then compared the findings with those of young healthy controls. fNIRS and electromyography were used simultaneously to detect prefrontal and masticatory muscle activities during chewing, while occlusal force and masticatory score were also examined by use of a food intake questionnaire. A significant increase in prefrontal activity was observed during chewing while wearing a denture, which was accompanied by increased masticatory muscle activity, occlusal force, and masticatory score, as compared with the tooth loss condition. Prefrontal activation during chewing while wearing a denture in the elderly subjects was not much different from that in the young controls. In contrast, tooth loss in the elderly group resulted in marked prefrontal deactivation, accompanied by decreased masticatory muscle activity, occlusal force, and masticatory score, as compared with the young controls. We concluded that intrinsic prefrontal activation during chewing with a denture may prevent prefrontal depression induced by tooth loss in elderly edentulous patients.
本研究的目的是阐明佩戴假牙对咀嚼过程中前额叶活动的影响。我们使用功能近红外光谱（fNIRS），特别检查了12名老年无牙受试者[63.1±6.1岁（均值±标准差）]和12名年轻健康对照者（22.1±2.3岁）的该活动，以评估在佩戴假牙和牙齿缺失情况下咀嚼过程中前额叶功能的质量，然后将结果与年轻健康对照者的结果进行比较。在咀嚼过程中同时使用fNIRS和肌电图来检测前额叶和咀嚼肌的活动，同时还通过食物摄入问卷来检查咬合力和咀嚼评分。与牙齿缺失情况相比，佩戴假牙咀嚼时观察到前额叶活动显著增加，同时伴有咀嚼肌活动、咬合力和咀嚼评分的增加。老年受试者佩戴假牙咀嚼时的前额叶激活与年轻对照者相比没有太大差异。相反，与年轻对照者相比，老年组的牙齿缺失导致前额叶明显失活，同时伴有咀嚼肌活动、咬合力和咀嚼评分的降低。我们得出结论，佩戴假牙咀嚼时前额叶的内在激活可能会预防老年无牙患者因牙齿缺失引起的前额叶抑制。
