Table 4 Findings from brain neuroimaging studies related to chewing published in the past five years
From: Revisiting the link between cognitive decline and masticatory dysfunction
Search criteria: 1. Key word combination: (chewing OR masticat* OR “tooth loss” OR “teeth loss”) AND MRI AND brain 2. Language: English 3. Publication date: 2012.10.15–2017.10.15 | ||
|---|---|---|
Reference | Task | MRI findings |
Inamochi et al. 2017 [78] | Chewing, before (Day 0) and after (Day 1/Day 7) inserting a palatal plate | Decreased activation in the bilateral face S1/M1, putamen, left ACC, and right medial posterior frontal cortex on Day 1 vs. Day 0. Activation in the right S1/M1 and putamen recovered to Day 0 level by Day 7. |
Choi et al. 2017 [65] | Gum chewing | Brain activations at the entorhinal cortex and the parahippocampal cortex, based on an region-of-interest analysis |
Lotze et al. 2017 [67] | Rubberdam chewing | Increased activation at bilateral S1, S2, M1, PMC, SMA and CG, anterior CB, INS, OFC, THA and left pallidum |
Lin et al. 2017 [74] | Resting (task-free) condition | The older subjects presented a different functional network associated with masticatory performance, compared to the younger subjects |
Lin et al. 2015 [72] | Resting (task-free) condition | Grey matter volume in the motor and frontal regions, and the functional connectivity of the cerebellum, was associated with masticatory performance |
Viggiano et al. 2015 [71] | After vs. before a mastication exercise (gum chewing) | Increased perfusion at the principal trigeminal nucleus but not in the dorsolateral-midbrain |
Jiang et al. 2015 [66] | Rhythmic chewing | Increased activation at sensorimotor cortex contralateral to the chewing side of preference (CSP), midbrain and brainstem for left CSP, and CB for right CSP |
Shoi et al. 2014 [70] | Gum chewing; full arch (with a removable partial denture, RPD) vs. short-dental arch (SDR) | Increased activation at middle FG, S1/M1, SMA, putamen, INS and CB for RPD group; no activation at middle FG in SDR group |
Luraschi et al. 2013 [68] | Three taska, patients with a complete denture | (Across all three functional tasks) increased activation at bilateral pre (M1) and post (S1) central gyrus |
Hirano et al. 2013 [81] | Two back-to-back ANT sessions with or without gum chewing | (During chewing) increased activation at anterior CG and left FG for the executive network; motor-related regions for attentional networks |
Quintero et al. 2013a [69] | Gum chewing | Increased activation at CB, motor cortex, caudate nucleus, CG, and brainstem |
Quintero et al. 2013b [73] | Gum chewing | Increased FC between bilateral M1 and S1, CB, CG and precuneus; increased FC between CB and contralateral CB, bilateral sensorimotor cortex, left superior temporal gyrus, and left CG |
Yu et al. 2013 [82] | Stress induced by loud noise; gum-chewing | Anterior INS – dACC FC was increased by noise to a lesser extent during gum-chewing (vs. no gum-chewing) |