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Clinical Oral Investigations Mar 2022To investigate the effects of dental/skeletal malocclusion and orthodontic treatment on four main objective parameters of chewing and jaw function (maximum occlusal bite... (Review)
Review
OBJECTIVE
To investigate the effects of dental/skeletal malocclusion and orthodontic treatment on four main objective parameters of chewing and jaw function (maximum occlusal bite force [MOBF], masticatory muscle electromyography [EMG], jaw kinematics, and chewing efficiency/performance) in healthy children.
MATERIALS AND METHODS
Systematic searches were conducted in MEDLINE (OVID), Embase, and the Web of Science Core Collection. Studies that examined the four parameters in healthy children with malocclusions were included. The quality of studies and overall evidence were assessed using the Joanna Briggs Institute and GRADE tools, respectively.
RESULTS
The searches identified 8192 studies; 57 were finally included. The quality of included studies was high in nine studies, moderate in twenty-three studies, and low in twenty-five studies. During the primary dentition, children with malocclusions showed similar MOBF and lower chewing efficiency compared to control subjects. During mixed/permanent dentition, children with malocclusion showed lower MOBF and EMG activity and chewing efficiency compared to control subjects. The jaw kinematics of children with unilateral posterior crossbite showed a larger jaw opening angle and a higher frequency of reverse chewing cycles compared to crossbite-free children. There was a low to moderate level of evidence on the effects of orthodontic treatment in restoring normal jaw function.
CONCLUSIONS
Based on the limitations of the studies included, it is not entirely possible to either support or deny the influence of dental/skeletal malocclusion traits on MOBF, EMG, jaw kinematics, and masticatory performance in healthy children. Furthermore, well-designed longitudinal studies may be needed to determine whether orthodontic treatments can improve chewing function in general.
CLINICAL RELEVANCE
Comprehensive orthodontic treatment, which includes evaluation and restoration of function, may or may not mitigate the effects of malocclusion and restore normal chewing function.
Topics: Bite Force; Child; Electromyography; Humans; Malocclusion; Masseter Muscle; Mastication; Masticatory Muscles
PubMed: 34985577
DOI: 10.1007/s00784-021-04356-y -
Current Opinion in Neurobiology Dec 2023Feeding behavior involves a complex organization of neural circuitry and interconnected pathways between the cortex, the brainstem, and muscles. Elevated synchronicity... (Review)
Review
Feeding behavior involves a complex organization of neural circuitry and interconnected pathways between the cortex, the brainstem, and muscles. Elevated synchronicity is required starting from the moment the animal brings the food to its mouth, chews, and initiates subsequent swallowing. Moreover, orofacial sensory and motor systems are coordinated in a way to optimize movement patterns as a result of integrating information from premotor neurons. Recent studies have uncovered significant discoveries employing various and creative techniques in order to identify key components in these vital functions. Here, we attempt to provide a brief overview of our current knowledge on orofacial systems. While our focus will be on recent breakthroughs regarding the masticatory machinery, we will also explore how it is sometimes intertwined with other functions, such as swallowing and limb movement.
Topics: Animals; Mastication; Neurons; Feeding Behavior; Movement; Brain Stem
PubMed: 37913688
DOI: 10.1016/j.conb.2023.102805 -
Sensors (Basel, Switzerland) Aug 2022The complexity of mandibular dynamics encourages constant research as a vehicle to improve oral health. The gold standard motion capture system might help us to... (Review)
Review
The complexity of mandibular dynamics encourages constant research as a vehicle to improve oral health. The gold standard motion capture system might help us to understand its functioning and its relation to body position, aiming to perform an exhaustive bibliographic review in the Dentistry field. Six different electronic databases were used (Dentistry & Oral Sciences Source, Scopus, Web of Science, PubMed, CINAHL and SPORTDiscus) in April 2022. The selection criteria includes a biography, critical analysis, and the full text from 1984 to April 2022, based on the odontological gold standard, whether or not in combination with additional devices. Clinical cases, bibliographic reviews or meta-analysis and grey literature were excluded. The checklist of the critical assessment methodology by Joanna Brigs was used (JBI). After choosing scientific articles published in peer-reviewed journals, 23 out of 186 investigations were classified as eligible with a total of 384 participants. The issue being addressed is related to the speech properties, posture and body movement in relation to dento-oro-facial muscle and facial analysis, mandibular kinematics and mandibular dynamics during the mastication process. The markers arrangement depends on the dynamic to be analysed. From a physiologic and pathologic perspective, the applications of the optic system are relevant in Dentistry. The scarcity of literature obtained implies the need for future research.
Topics: Biomechanical Phenomena; Checklist; Humans; Mastication; Muscles
PubMed: 35957324
DOI: 10.3390/s22155769 -
BMJ Case Reports Apr 2022
Topics: Eye Movements; Humans; Mastication; Vision Disorders
PubMed: 35418373
DOI: 10.1136/bcr-2021-245382 -
Nutrients Nov 2022Current methods to detect eating behavior events (i.e., bites, chews, and swallows) lack objective measurements, standard procedures, and automation. The video... (Review)
Review
Current methods to detect eating behavior events (i.e., bites, chews, and swallows) lack objective measurements, standard procedures, and automation. The video recordings of eating episodes provide a non-invasive and scalable source for automation. Here, we reviewed the current methods to automatically detect eating behavior events from video recordings. According to PRISMA guidelines, publications from 2010-2021 in PubMed, Scopus, ScienceDirect, and Google Scholar were screened through title and abstract, leading to the identification of 277 publications. We screened the full text of 52 publications and included 13 for analysis. We classified the methods in five distinct categories based on their similarities and analyzed their accuracy. Facial landmarks can count bites, chews, and food liking automatically (accuracy: 90%, 60%, 25%). Deep neural networks can detect bites and gesture intake (accuracy: 91%, 86%). The active appearance model can detect chewing (accuracy: 93%), and optical flow can count chews (accuracy: 88%). Video fluoroscopy can track swallows but is currently not suitable beyond clinical settings. The optimal method for automated counts of bites and chews is facial landmarks, although further improvements are required. Future methods should accurately predict bites, chews, and swallows using inexpensive hardware and limited computational capacity. Automatic eating behavior analysis will allow the study of eating behavior and real-time interventions to promote healthy eating behaviors.
Topics: Feeding Behavior; Mastication; Food; Communications Media; Neural Networks, Computer
PubMed: 36432533
DOI: 10.3390/nu14224847 -
BioMed Research International 2015Exposure to chronic stress induces various physical and mental effects that may ultimately lead to disease. Stress-related disease has become a global health problem.... (Review)
Review
Exposure to chronic stress induces various physical and mental effects that may ultimately lead to disease. Stress-related disease has become a global health problem. Mastication (chewing) is an effective behavior for coping with stress, likely due to the alterations chewing causes in the activity of the hypothalamic-pituitary-adrenal axis and autonomic nervous system. Mastication under stressful conditions attenuates stress-induced increases in plasma corticosterone and catecholamines, as well as the expression of stress-related substances, such as neurotrophic factors and nitric oxide. Further, chewing reduces stress-induced changes in central nervous system morphology, especially in the hippocampus and hypothalamus. In rodents, chewing or biting on wooden sticks during exposure to various stressors reduces stress-induced gastric ulcer formation and attenuates spatial cognitive dysfunction, anxiety-like behavior, and bone loss. In humans, some studies demonstrate that chewing gum during exposure to stress decreases plasma and salivary cortisol levels and reduces mental stress, although other studies report no such effect. Here, we discuss the neuronal mechanisms that underline the interactions between masticatory function and stress-coping behaviors in animals and humans.
Topics: Adaptation, Psychological; Animals; Anxiety; Catecholamines; Cognition Disorders; Hippocampus; Humans; Mastication; Stress, Psychological
PubMed: 26090453
DOI: 10.1155/2015/876409 -
Journal of Oral Rehabilitation Jun 2021A large number of methodological procedures and experimental conditions are reported to describe the masticatory process. However, similar terms are sometimes employed... (Review)
Review
A large number of methodological procedures and experimental conditions are reported to describe the masticatory process. However, similar terms are sometimes employed to describe different methodologies. Standardisation of terms is essential to allow comparisons among different studies. This article was aimed to provide a consensus concerning the terms, definitions and technical methods generally reported when evaluating masticatory function objectively and subjectively. The consensus is based on the results from discussions and consultations among world-leading researchers in the related research areas. Advantages, limitations and relevance of each method are also discussed. The present consensus provides a revised framework of standardised terms to improve the consistent use of masticatory terminology and facilitate further investigations on masticatory function analysis. In addition, this article also outlines various methods used to evaluate the masticatory process and their advantages and disadvantages in order to help researchers to design their experiments.
Topics: Consensus; Humans; Mastication
PubMed: 33638156
DOI: 10.1111/joor.13161 -
The Angle Orthodontist Mar 2022To investigate the masticatory (masticatory performance, bite force, swallowing threshold, muscle activity, and questionnaires) and nutritional (nutrient intake) impacts... (Review)
Review
OBJECTIVES
To investigate the masticatory (masticatory performance, bite force, swallowing threshold, muscle activity, and questionnaires) and nutritional (nutrient intake) impacts of the activation and/or installation of different orthodontic appliances (fixed labial, lingual appliances, and clear aligners).
MATERIALS AND METHODS
Six electronic databases and gray literature were searched (up to May 2021) for relevant studies evaluating mastication and nutrition after activation/installation of orthodontic appliances. This review followed PRISMA guidelines and was registered at PROSPERO (CRD42020199510). The risk of bias (RoB 2 and ROBINS-I) and evidence quality Grading of Recommendations Assessment, Development, and Evaluation were analyzed.
RESULTS
Of 4226 recorded and screened, 15 studies were finally included. Masticatory performance (standardized mean difference [SMD]: 1.069; 95% coefficient interval [CI]: 0.619 to 1.518) and bite force (SMD: -2.542; 95% CI: -4.867 to -0.217) reduced in the first 24 to 48 hours of fixed labial appliance installation/activation, but they were both normalized after 30 days (P > .05). The swallowing threshold remained constant (P > .05). Nutritional intake was rarely reported but showed copper (P = .002) and manganese (P = .016) reductions, with higher calorie and fat intake (P < .05). Lingual appliances impacted chewing more than labial, and clear aligner wearers reported fewer chewing problems (P < .001). Low to very low levels of evidence were found.
CONCLUSIONS
Based on low to very low levels of evidence, mastication was reduced during the first 24 to 48 hours of fixed labial appliance activation/installation, but it was transitory (up to 30 days). Due to insufficient data, the nutritional impact of orthodontic appliances was not conclusive.
Topics: Bite Force; Mastication; Orthodontic Appliances; Orthodontic Appliances, Fixed; Tongue
PubMed: 34878525
DOI: 10.2319/061221-469.1 -
International Journal of Medical... 2015Mastication (chewing) is important not only for food intake, but also for preserving and promoting the general health. Recent studies have showed that mastication helps... (Review)
Review
Mastication (chewing) is important not only for food intake, but also for preserving and promoting the general health. Recent studies have showed that mastication helps to maintain cognitive functions in the hippocampus, a central nervous system region vital for spatial memory and learning. The purpose of this paper is to review the recent progress of the association between mastication and the hippocampus-dependent cognitive function. There are multiple neural circuits connecting the masticatory organs and the hippocampus. Both animal and human studies indicated that cognitive functioning is influenced by mastication. Masticatory dysfunction is associated with the hippocampal morphological impairments and the hippocampus-dependent spatial memory deficits, especially in elderly. Mastication is an effective behavior for maintaining the hippocampus-dependent cognitive performance, which deteriorates with aging. Therefore, chewing may represent a useful approach in preserving and promoting the hippocampus-dependent cognitive function in older people. We also discussed several possible mechanisms involved in the interaction between mastication and the hippocampal neurogenesis and the future directions for this unique fascinating research.
Topics: Cognition; Hippocampus; Humans; Learning; Mastication; Memory; Neurogenesis
PubMed: 26078711
DOI: 10.7150/ijms.11911 -
BioMed Research International 2015
Topics: Humans; Mastication; Stress, Psychological
PubMed: 26078950
DOI: 10.1155/2015/412493