OBJECTIVE: Mouthguards are crucial for protecting athletes against orofacial injuries, yet concerns persist regarding their potential impact on oral functions. This study aimed to investigate the effects of sports mouthguards on oral functions and speech over time.
METHODS: Thirty national rugby players received custom-fitted mouthguards. Questionnaire responses and speech recordings were collected before mouthguard use and at various intervals after using mouthguards: immediately, 1 week, 2 month, and 6 months. Spectrographic analysis was performed to measure voice onset time (VOT) for /p, b, t, d/ phonemes. Questionnaire responses were assessed with Friedman\'s test, while VOT changes were examined using one-way repeated measure analysis of variance.
RESULTS: Compliance with mouthguard use improved during training and competitions, with consistent wear reported during matches. Over time, speaking difficulties and lisping decreased significantly (p < .001). The perception of nausea improved (p < .001), stabilizing after 1 month (p = .414). Sensations of bulkiness declined (p < .001). Mouth dryness reduced steadily, with no occurrences reported by all players by the end of the study. None of the participants reported bad breath, ulcers, or redness in the mouth. VOT changed immediately after wearing mouthguards (p < .001), gradually regressing toward the baseline, although not completely reaching it. Players held a favorable view of mouthguard use, with comfort and support for mandatory use increasing over time.
CONCLUSIONS: Custom-fitted mouthguards do not lead to significant long-term disruptions in oral functions. Athletes generally adapt to mouthguard use, reporting improved comfort and greater support for their use.

暂无摘要。

Cognitive impairment and subsequent dementia are the major causes of disability and need for nursing care among older people in worldwide. The purpose is to review well-known risk factors for cognitive impairment and dementia, focusing on the relationship between decline in oral function and current prevention strategies. Various non-modifiable and modifiable risk factors are related to cognitive impairment. Effects of oral function to cognitive impairment is not yet well recognized in the medical community, although masticatory function, occlusal force, and number of teeth have been reported to be related to cognitive function. Furthermore, occlusal force rather than number of teeth was significantly related to the early stages of cognitive impairment, and that a decline in occlusal force seemed to lead to cognitive impairment directly and indirectly through dietary intake. This relationship was significant only for occlusal force, which may be associated with the early stages of cognitive decline. Nutritional change caused by reduced masticatory function is suggested as a possible explanation. Therefore, rehabilitation or maintenance of oral function should be sought to prevent cognitive impairment.

The aim of this retrospective cross-sectional study was to comprehensively assess masticatory function in maxillectomy patients with functioning removable prostheses. Their general and oral profiles, the measurement values of their oral functions, including masticatory function, and the history of tumor therapy were extracted from medical charts. The correlations of masticatory function with numerical data and the effects of tumor therapy-related factors on masticatory function were evaluated. In addition, a stepwise conditional logistic regression analysis was performed to identify the potential predictive factors comprehensively. The data from 55 maxillectomy patients revealed that the median value of masticatory function (138.0 mg/dL) was higher than the threshold (100.0 mg/dL) based on the concept of oral hypofunction. Moderate correlations of masticatory function with the number of remaining teeth, the number of functioning occlusal supports, and maximum occlusal force were found, as well as a weak correlation with maximum tongue pressure. These variables also showed statistically significant coefficients (p < 0.01). No significant effect of each tumor therapy-related factor on masticatory function was detected. A logistic regression analysis identified the number of functioning occlusal supports as a significant predictive factor. These results implied the crucial interactions of masticatory function with various factors and the specificities of maxillectomy patients.

The temporomandibular joints (TMJs) are the only joints in the human skull and regulate all mandibular motions. The functions of TMJs are considerably influenced by their biomechanical surroundings. However, owing to the unique characteristics of TMJs, comprehending their kinematic and biomechanical mechanisms remains challenging. As a result, understanding how biomechanics relate to TMJ structures and motions is critical in subsequent therapies. The goal of this study is to investigate any links between morphological or kinematic factors and discal stresses during mouth opening. Our study included eight asymptomatic participants who did not show any signs or symptoms of temporomandibular disorders. The morphological parameters, kinematic properties, and stresses were determined using computed tomography (CT), magnetic resonance imaging (MRI), and subject-specific movements. Following the investigation, we discovered that the opening of the mouth was not the primary cause of TMJ stress. The stress on the discs is directly linked to condylar displacements during mouth opening. Furthermore, morphological characteristics related to the relative position of the condyles in the glenoid fossa at the intercuspal position have a limited effect on condylar displacements and stresses. In conclusion, the morphological parameters, which are commonly employed in clinics, show only static conditions in the TMJs. The kinematic parameters provide dynamic information regarding the TMJs, which can be used in the examination, diagnosis, and treatment of TMJ diseases to reduce stress.

BACKGROUND: To review the evidence on the oral health-related quality of life (OHRQoL) of head and neck cancer survivors after they have been treated with prosthetic rehabilitation.
METHODS: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were utilized as the framework in designing, implementing and reporting the current review. Search of literature was done electronically using Medline, Embase, and Cochrane databases. Intervention component of the patient, intervention, comparison, outcome (PICO) for the current review was the prosthetic rehabilitation performed on the surgically treated head and neck cancer patients (participants); and outcome was the OHRQoL. Methodological index for non-randomized studies was the assessment tool utilized to report on the quality of the included studies.
RESULTS: The initial search had identified 799 records and the final level of screening included eight articles. Six studies were experimental in design and two were cross-sectional. Cumulative sample of the head and neck cancer cases from the selected studies was 354, with 35.9 (14.9) and 72.4 (8.7) years as the highest and lowest mean age recorded from the included studies. More male cases (69.5%) were reported than female cases (30.5%) and squamous cell carcinoma was the most commonly diagnosed malignancy. Maxillary reconstruction and implant supported prosthesis were the choice of treatment for most of the cases. Different versions of oral health impact profile (OHIP) constructs were preferred by six studies. While, one study utilized University of Washington quality of life questionnaire and the other utilized European Organization for Research and Treatment of Cancer\'s Quality of Life Questionnaire. Arguably, three studies had compared the OHRQoL scores of head and neck cancer patients with healthy counterparts through a follow-up period ranging from 1 to 2 years.
CONCLUSIONS: The included studies did not provide substantial evidence to demonstrate the improvement in OHRQoL of head and neck cancer patients after prosthetic rehabilitation. More prospective studies are needed with representative sample, robust methodology and a longer follow-up period. The current study provides a direction to the clinical decision-making process and the epidemiological research to enhance the patients and public health-related outcomes.

BACKGROUND: Many physical functions decline with aging, but it is not known whether oral functions vary according to sex or decline with aging, as it occurs with physical functions. The present study aimed to examine the association of sex, age, and elapsed years with occlusal force and tongue pressure using a generalized linear mixed-effect model (GLMM) over a 3-year period among old-old Japanese adults.
METHODS: Participants were community-dwelling older adults who participated in a survey (June 2014-March 2017) and a follow-up survey (July 2017-December 2019) after 3 years (n = 951: 70-year group, n = 466; 80-year group, n = 391; 90-year group, n = 94). Dental examinations including the number of teeth, occlusal force, and tongue pressure were conducted, and a GLMM was used to estimate the association of sex, age, and elapsed years with occlusal force and tongue pressure, adjusting for the number of teeth.
RESULTS: The GLMM showed that occlusal force was significantly associated with sex (reference; male, non-standardized coefficient: B = -66.9 [female], p < 0.001), age (reference; 70-year group, B = -81.7 [80-year group], p < 0.001, B = -87.2 [90-year group], p < 0.001), and the number of teeth (B = 13.8, p < 0.001), but did not significantly decrease with elapsed years. Tongue pressure was significantly associated with sex (reference; male, B = -0.94 [female], p = 0.034) and age (reference; 70-year group, B = -1.78 [80-year group], p < 0.001, B = -5.47 [90-year group], p < 0.001). Tongue pressure decreased significantly with elapsed years (B = -0.82, p < 0.001).
CONCLUSIONS: These findings suggest that tongue pressure significantly decreased over time, but occlusal force did not. Tongue-related muscles may be more susceptible to aging than masticatory muscles.

OBJECTIVE: To evaluate masticatory performance (MP), maximum occlusal force (MOF), maximum tongue pressure (MTP) and oral diadochokinesis (ODK) among community-dwelling elderly patients without posterior occlusal support.
METHODS: This study enrolled community-dwelling elderly patients (≥65 years old) who belonged to Eichner A, B4, C1, C2, and C3. Each oral function was statistically compared among groups. Correlations between MP and other variables were examined in Eichner B4 and C patients.
RESULTS: MP and MOF values in Eichner B4 and C patients were significantly lower than in Eichner A patients. There were significant differences in MTP values between Eichner \"A and C2, C3\", and \"B4 and C2, C3\". ODK in Eichner C patients showed significantly lower values compared to Eichner A patients in general. Although there were statistically significant correlations of MP with age, the number of remaining teeth and all oral functions were identified, and multiple regression analysis indicated that MOF and MTP were independently related to MP.
CONCLUSIONS: Oral functions in Eichner B4 and C patients were lower compared to Eichner A patients. MP was significantly correlated with MOF and MTP in elderly patients without posterior occlusal support, suggesting the importance of rehabilitation of MOF and MTP in MP.

New lines of evidence suggest that the oral-systemic medical links and oral hypo-function are progressively transcending beyond the traditional clinical signs and symptoms of oral diseases. Research into the dysbiotic microbiome, host immune/inflammatory regulations and patho-physiologic changes and subsequent adaptations through the oral-systemic measures under ageism points to pathways leading to mastication deficiency, dysphagia, signature brain activities for (neuro)-cognition circuitries, dementia and certain cancers of the digestive system as well. Therefore, the coming era of oral health-linked systemic disorders will likely reshape the future of diagnostics in oral geriatrics, treatment modalities and professional therapies in clinical disciplines. In parallel to these highlights, a recent international symposium was jointly held by the International Association of Gerontology and Geriatrics (IAGG), Japanese Society of Gerodontology (JSG), the representative of USA and Taiwan Academy of Geriatric Dentistry (TAGD) on Oct 25th, 2019. Herein, specific notes are briefly addressed and updated for a summative prospective from this symposium and the recent literature.

Glycogen storage disease type II (GSDII) or Pompe disease is a rare autosomal recessive metabolic disorder that leads to intracellular glycogen storage in many tissues, mainly in skeletal muscle, heart and liver. Facial muscle weakness and altered craniofacial growth are very common in Pompe disease children. In this paper we describe the orofacial features in two children affected by GSDII and illustrate a multidisciplinary approach that involved enzyme replace therapy, non-invasive ventilation (NIV) and pediatric dentistry with 5-year follow-up.
Two Infantile Pompe Disease children were examined by a pediatric dentist at the age of 4 and 5 years old respectively. The orofacial examination showed typical facies with similar features: hypotonia of facial and tongue muscles, lip incompetence, narrow palate with reduction in transversal dimension of the upper dental arch, macroglossia, low position of the tip of the tongue, concave profile, Class III malocclusion with hypoplasia of maxillary-malar area and mandibular prognathism. Myofunctional therapy and orthodontic treatment consisted in oral muscle exercises associated to intraoral and extraoral orthodontic devices. NIV facial mask was substituted with a nasal pillow mask in order to avoid external pressure on the mid-face which negatively influences craniofacial growth.
This paper evidences that the pediatric dentist plays an important role in craniofacial growth control, oral function rehabilitation and, therefore, in the improvement of the quality of life of Pompe children and their families. Therefore an early pediatric dental evalutation should be included in the multidisciplinary management of children suffering from Infantile Pompe Disease.