Comparison of the effect of conventional and implant-retained overdentures on brain activity and cognition in a geriatric population - A functional MRI study

Abstract

This study aims to evaluate the effect of rehabilitation with complete dentures versus implant-retained overdenture on activity in various parts of the brain cognition in a geriatric edentulous population via Functional MRI (fMRI) studies and the Mini-Mental State Examination (MMSE). Methods: Ten completely edentulous patients were rehabilitated with both complete dentures and two-implant retained overdentures for three months each. fMRI studies were performed for each modality during chewing and recall tasks at three time periods: T0: Completely Edentulous(CE) T1: after three months of wearing Conventional Complete Dentures(CD) and T2: after three months of wearing Implant-retained Overdentures (IOD). The Z scores obtained from the fMRI at these phases of examination were tabulated and correlated with MMSE scores obtained at the corresponding time periods. Results: Z scores obtained during the memory recall tasks at T2 were the greatest (Prefrontal Cortex (p=0.059) and Hippocampus (p=0.036). The MMSE scores obtained were significantly higher for the IODs when compared to the CDs and Baseline values (p < 0.05) Conclusion: IODs may potentially result in superior sensory feedback in edentulous patients and lead to improved cognitive performance when compared to conventional complete dentures.

Functional Neuroplasticity of Adults with Partial or Complete Denture Rehabilitation with or without Implants: Evidence from fMRI Studies

“…Each study recruited approximately 4–20 patients. One study reported details on the sample size calculation [ 23 ], whereas another study simply mentioned that the “sample size was calculated to be seven” [ 24 ]. No study explicitly mentioned the socioeconomic background or ethnicity of the subjects.…”

“…Two studies were cross-sectional with between-group comparisons [ 27 , 28 ]. Meanwhile, only three studies collected brain activity data from their patients before the experimental interventions: Two collected data while patients were wearing their old complete dentures [ 23 , 29 ], and one collected data while patients were completely edentulous, without dentures [ 24 ]. Brain activation in response to several tasks was assessed, with the most popular task being jaw (denture teeth) clenching and gum-chewing.…”

“…For Yan et al [ 27 ], concerns were raised regarding confounding variables, as they had compared patients who already had undergone different types of denture rehabilitations, without disclosing or accounting for the differences in the socioeconomic status between the patient groups. Significant risks were identified in the incomplete outcome data for three studies [ 24 , 28 , 32 ], as they had analyzed the fMRI data based on their subjective judgments (i.e., “no signal”, “mild signal”, versus “strong signal”) instead of the routine statistical tests based on numerical values. Due to the heterogeneity of the studies and the lack of brain coordinates reported by the studies, a neuroimaging meta-analysis was not feasible.…”

“…Circumstantial evidence from jaw-clenching studies regarding complete edentulous individuals rehabilitated with complete dentures, implant-supported overdentures, or implant-supported fixed dentures ( n = 2) [ 27 , 28 ] suggested that the implant-supported fixed dentures could be the best option, as compared to implant-supported overdentures and complete dentures, as it was associated with higher brain activity levels in various brain regions, including those corresponding to the primary sensory (PostCG) and motor cortices (PreCG). Gum-chewing studies ( n = 4, one with partial edentulous participants) [ 23 , 24 , 25 , 31 ] found that the brain activity levels in various brain regions, such as the prefrontal cortex, PreCG, and the parietal cortex, could be improved by having a dental arch fully replaced, instead of partially replaced, or having a new complete denture replacement. Implant-supported overdenture were associated with lower brain activity levels than those in edentulous patients, but the studies related to these conditions had mixed results, as compared to those with complete dentures.…”

Leadership for the further growth of <i>JPR </i>

“…This issue of JPR addresses a variety of topics, particularly regarding elderly people, including a study to develop a simple screening test for mastication [4], image analysis to clarify the effects of food particle loss on the evaluation of masticatory ability [5], and finding an association between abnormal masticatory movement and oral/physical function, possibly influenced by central motor control [6]. Interestingly, Padmanabhan et al [7] observed superior sensory feedback and improved cognitive performance in edentulous patients with implant-retained overdentures compared with those with conventional complete dentures. Many Asian countries are now facing a rapidly aging population, where partially edentate patients are increasing in incidence with frailty, cognitive impairment, and mul-tiple chronic diseases [8].…”