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Laryngoscope Investigative... Aug 2021The mandible is a critical structure of the lower facial skeleton which plays an important role in several vital functions. Segmental resection of the mandible is at... (Review)
Review
The mandible is a critical structure of the lower facial skeleton which plays an important role in several vital functions. Segmental resection of the mandible is at times required in patients with advanced oral cavity malignancies, primary mandibular tumors, and radiation or medication induced osteonecrosis. Mandibulectomy can significantly decrease quality of life, and thus mandibular reconstruction is an important aspect of the operative plan. Mandibular reconstruction is challenging due to the complex three-dimensional anatomy of the mandible, and the precision required to restore dental occlusion in dentate patients. Significant advances have been made over the past decade in the ability to reconstruct and rehabilitate patients after a segmental mandibulectomy. This review will highlight these advances and discuss the timing of dental implantation.
PubMed: 34401495
DOI: 10.1002/lio2.595 -
Oral Surgery, Oral Medicine, Oral... Jul 2021Oral health and balanced occlusion are important aspects of a well-functioning face transplant. This study describes the oral and dental status, dental management, and...
OBJECTIVES
Oral health and balanced occlusion are important aspects of a well-functioning face transplant. This study describes the oral and dental status, dental management, and sialoendoscopy of the first 2 patients in Helsinki who underwent face transplantations.
STUDY DESIGN
Two patients received near-full face transplantations in 2016 and 2018, respectively. The transplanted tissues included a Le Fort type II maxilla, angle-to-angle mandible, all oral mucosa, ventral tongue tissue, and the muscles of the floor of the mouth. Comprehensive oral examinations and all required dental treatment, including follow-up examinations, were performed for both patients after the transplantations.
RESULTS
Both patients rehabilitated well, and their quality of life improved. Stable, functioning dentition and occlusion were achieved for both patients. Hyposalivation and dental caries were issues for both patients. Patient 1 also experienced infections in the jaws. Implants were placed in the transplanted jaws of patient 2 with successful osseointegration.
CONCLUSIONS
We report successful tooth-bearing face transplantations in 2 patients. Patient selection, particularly regarding oral health, is crucial in avoiding posttransplantation complications. Moreover, the oral and dental status of the donor should be examined by a dentist before transplantation, and regular follow-up dental examinations should be performed after transplantation.
Topics: Dental Caries; Dental Implants; Dental Prosthesis, Implant-Supported; Facial Transplantation; Follow-Up Studies; Humans; Mandible; Maxilla; Quality of Life
PubMed: 33563570
DOI: 10.1016/j.oooo.2021.01.006 -
Frontiers in Neural Circuits 2021Neurons in the trigeminal mesencephalic nucleus (Vme) have axons that branch peripherally to innervate the orofacial region and project centrally to several motor nuclei...
Neurons in the trigeminal mesencephalic nucleus (Vme) have axons that branch peripherally to innervate the orofacial region and project centrally to several motor nuclei in brainstem. The dorsal motor nucleus of vagus nerve (DMV) resides in the brainstem and takes a role in visceral motor function such as pancreatic exocrine secretion. The present study aimed to demonstrate the presence of Vme-DMV circuit, activation of which would elicit a trigeminal neuroendocrine response. A masticatory dysfunctional animal model termed unilateral anterior crossbite (UAC) model created by disturbing the dental occlusion was used. Cholera toxin B subunit (CTb) was injected into the inferior alveolar nerve of rats to help identify the central axon terminals of Vme neurons around the choline acetyltransferase (ChAT) positive motor neurons in the DMV. The level of vesicular glutamate transporter 1 (VGLUT1) expressed in DMV, the level of acetylcholinesterase (AChE) expressed in pancreas, the level of glucagon and insulin expression in islets and serum, and the blood glucose level were detected and compared between UAC and the age matched sham-operation control mice. Data indicated that compared with the controls, there were more CTb/VGLUT1 double labeled axon endings around the ChAT positive neurons in the DMV of UAC groups. Mice in UAC group expressed a higher VGLUT1 protein level in DMV, AChE protein level in pancreas, glucagon and insulin level in islet and serum, and higher postprandial blood glucose level, but lower fasting blood glucose level. All these were reversed at 15-weeks when UAC cessation was performed from 11-weeks (all, < 0.05). Our findings demonstrated Vme-DMV circuit which the aberrant occlusion elicited a trigeminal neuroendocrine response such as alteration in the postprandial blood glucose level. Dental occlusion is proposed as a potential therapeutic target for reversing the increased postprandial glucose level.
Topics: Acetylcholinesterase; Animals; Dental Occlusion; Mice; Motor Neurons; Rats; Rats, Sprague-Dawley; Vagus Nerve
PubMed: 33776655
DOI: 10.3389/fncir.2021.638000 -
American Journal of Orthodontics and... Nov 2023Oral appliance (OA) therapy in obstructive sleep apnea (OSA) could be a risk factor for normal jaw function, given the prolonged effect of an OA in keeping the mandible...
INTRODUCTION
Oral appliance (OA) therapy in obstructive sleep apnea (OSA) could be a risk factor for normal jaw function, given the prolonged effect of an OA in keeping the mandible in a protruded position away from a normal position. This study aimed to assess changes in symptoms and clinical findings related to jaw function after 1 year of treating OSA with an OA.
METHODS
In this follow-up clinical trial, 302 patients with OSA were assigned to treatment with either monobloc or bibloc OA. Baseline and 1-year follow-up assessment included using the Jaw Functional Limitation Scale, self-reported symptoms and signs related to jaw function. The clinical examination of jaw function included mandibular mobility, dental occlusion, and tenderness in the temporomandibular joints and masticatory muscles. Descriptive analyses of variables are presented for the per-protocol population. To evaluate differences between the baseline and the 1-year follow-up, paired Student t tests and the McNemar change test was used.
RESULTS
One-hundred and ninety-two patients completed the 1-year follow-up (male 73%, mean aged 55 ± 11 years). There was no change in the Jaw Functional Limitation Scale score at the follow-up (nonsignificant). The patients described no change in symptoms at the follow-up, except for improvements in morning headache (P <0.001) and increased frequency of difficulties in opening the mouth or chewing on awakening (P = 0.002). Subjectively reported changes in dental occlusion during biting/chewing increased significantly at the follow-up (P = 0.009).
CONCLUSIONS
No changes in measurements of jaw mobility, dental occlusion, or pain on palpation of the temporomandibular joints or masticatory muscles were seen at the follow-up. Thus, using an OA in treating OSA had limited influence on jaw functions and related symptoms. Moreover, the risk of developing pain and functional impairment in the masticatory system was infrequent, indicating that this treatment is safe and can be recommended.
Topics: Humans; Male; Adult; Middle Aged; Aged; Temporomandibular Joint; Pain; Mandible; Temporomandibular Joint Disorders; Mandibular Advancement; Sleep Apnea, Obstructive; Treatment Outcome
PubMed: 37318425
DOI: 10.1016/j.ajodo.2023.04.018 -
Journal of Occupational Medicine and... Feb 2021Symmetrical dental occlusion blocking is used in dentistry as a quick diagnostic tool to test for potential influences of the craniomandibular system on body sway and...
OBJECTIVES
Symmetrical dental occlusion blocking is used in dentistry as a quick diagnostic tool to test for potential influences of the craniomandibular system on body sway and weight distribution. This study presents the changes of body sway and pressure distribution in healthy subjects, free of a temporomandibular dysfunction (TMD). Immediate effects between occlusal blocking and rest position on body sway and body weight distribution in general, as well as for both genders and for four age decades will be evaluated.
MATERIALS AND METHODS
725 (396f/329 m) subjects (neither subjective signs of TMD nor acute/chronic complaints in the musculoskeletal system) volunteered (21 to 60 years) while both genders were divided into four age groups according to decades. A pressure measuring platform was used. Body sway and weight distribution were recorded in two dental occlusion conditions (a) in rest position and (b) symmetrical blocking (bicuspid region) by cotton rolls.
RESULTS
Both, the frontal sway and the sagittal sway reduced by 0.67 mm (t(724) = - 3.9 (p < 0.001)) and by 0.33 mm (t(724) = - 3.4 (p < 0.001)). The relative pressure under the left forefoot increased by 0.33% (t(724) = 2.88 (p < 0.001)) and the relative pressure overall under the forefoot increased by 0.67% (t(724) = - 3.4 (p < 0.001)). Gender-specific, age-specific and BMI-specific reactions could not be identified.
CONCLUSIONS
Subjects, free of any TMD and with no complaints of the musculoskeletal system, show small changes of the body sway and weight distribution when biting symmetrically on a cotton roll. These changes are independent of age, gender or body mass index (BMI). Due to the relative large sample size, the presented results can also be seen as norm values when body sway is used as an additional assessment of a TMD.
PubMed: 33639978
DOI: 10.1186/s12995-021-00296-1 -
International Journal of Environmental... Jan 2022Bite force is an important indicator of masticatory performance. However, existing methods for measuring bite force are either ineffective or expensive. Hence, we...
Bite force is an important indicator of masticatory performance. However, existing methods for measuring bite force are either ineffective or expensive. Hence, we developed a novel capacitive-type pressure-mapping sensor that converts mechanical forces into changes in capacitance and calculates bite force. A portable device was fabricated based on this sensor sheet, and the accuracy of the bite-force measurements provided by the device was evaluated. The sensor has a thickness of 1.6 mm and has 63 measurement points. It was inserted into a dental model, where the output value was measured and compared with that of a universal testing machine (AG-IS 100 kN). A regression equation to estimate the bite force was obtained based on the relationship between the output of the capacitive-type pressure-mapping sensor and that of the load cell of the universal testing machine. The estimated bite force from the sensor and the quadratic regression equation closely resembled the known load applied by the compression tester (R = 0.992). We therefore conclude that the developed sensor can measure bite force accurately and effectively. A device with a built-in capacitive-type pressure-mapping sensor can potentially be a user-friendly tool for bite-force measurements in both clinical and epidemiological settings.
Topics: Bite Force; Mechanical Phenomena; Pressure
PubMed: 35162299
DOI: 10.3390/ijerph19031273 -
British Dental Journal May 2024Dental implants are a regular feature in daily clinical practice and there is a need to undertake routine assessment and maintenance of implants and their restorations... (Review)
Review
Dental implants are a regular feature in daily clinical practice and there is a need to undertake routine assessment and maintenance of implants and their restorations on par with that provided for natural teeth. Occlusal checks form an important part of the maintenance regime for preserving the integrity of implants, their restorations, and health of the peri-implant tissues. Implant restorations are subjected to the full characteristics and magnitude of occlusal forces, including those associated with parafunction. Compared with the periodontal ligament around teeth, the biophysical response to occlusal forces of osseointegration is different through the more rigid link of implant to bone and reduced proprioception. Risks attributable to occlusal forces primarily affect implant restorations and they are elevated in the presence of bruxism. The occlusal guidelines recommended by the literature are aimed at reducing these risks and regular assessment and maintenance of the occlusion is essential. A four-step sequence is presented to ensure that the annual occlusal checks include the patient's input and evaluation of restoration integrity, occlusal scheme, additional protection, and spatial changes.
Topics: Humans; Dental Implants; Bite Force; Dental Occlusion; Bruxism
PubMed: 38789754
DOI: 10.1038/s41415-024-7407-7 -
Clinical Nutrition (Edinburgh, Scotland) Aug 2021Patients with amyotrophic lateral sclerosis (ALS) develop swallowing difficulties with the progression of the disease. The present study aimed at comparing oral function...
BACKGROUND & AIMS
Patients with amyotrophic lateral sclerosis (ALS) develop swallowing difficulties with the progression of the disease. The present study aimed at comparing oral function and body composition between ALS patients and healthy controls, and at evaluating which parameters are the most discriminant between both groups.
METHODS
We included ALS patients at the start of their multidisciplinary follow-up at the Geneva University Hospitals and healthy age-, gender-, and dental status-matched adults. We assessed the severity of the disease through the ALS Functional Rating Scale and the swallowing difficulties through the EAT-10 score. We performed an intraoral examination of the dental status, and measured chewing performance, bite, lip and tongue force, saliva weight, and body composition. Group comparisons were performed with t-tests or Mann-Whitney tests as appropriate. Linear discriminant analysis was used to determine the most discriminant parameters between groups.
RESULTS
Twenty-six ALS patients (bulbar onset: n = 7, median (IQR) ALS Functional Rating Scale: 37 (11)) were included. The ALS patients had a significantly lower chewing performance (p < 0.001), lip force (p < 0.001), tongue force (p = 0.002), saliva weight (p < 0.004) and fat-free mass index (p < 0.001) as compared to the healthy individuals, and a higher EAT-10 score (p < 0.001). In ALS patients, a low chewing performance was correlated with a low bite (r = -0.45, p < 0.05)) and tongue force (r = -0.59, p < 0.05). The most discriminant parameters between both groups, by order of importance, were chewing performance, fat-free mass index and saliva weight and allowed the calculation of a discriminant function.
CONCLUSION
Compared to healthy controls, ALS patients have significant alterations of oral function and body composition. The most discriminant parameters between both groups were chewing performance, fat-free mass index and saliva volume. It remains to be demonstrated whether oral parameters predict outcome. CLINICAL TRIAL REGISTRY: clinicaltrials.gov, identifier: NCT01772888.
Topics: Aged; Amyotrophic Lateral Sclerosis; Bite Force; Body Composition; Case-Control Studies; Deglutition; Deglutition Disorders; Female; Humans; Lip; Male; Mastication; Middle Aged; Saliva; Severity of Illness Index; Tongue
PubMed: 34358835
DOI: 10.1016/j.clnu.2021.06.022 -
Korean Journal of Orthodontics Nov 2023: To investigate the potential correlation between fixed orthodontic retention failure and several patient- and treatment-related factors.
OBJECTIVE
: To investigate the potential correlation between fixed orthodontic retention failure and several patient- and treatment-related factors.
METHODS
: Patients finishing treatment with fixed appliances between 2016 and 2017 were retrospectively included in this study. Those not showing fixed retention failure were considered as control group. Patients with fixed retention failure were considered as the experimental group. Additionally, patients with failure of fixed retainers in the period of June 2019 to March 2021 were prospectively identified and included in the experimental group. The location of the first retention failure, sex, pretreatment dental occlusion, facial characteristics, posttreatment dental occlusion, treatment approach and presence of oral habits were compared between groups before and after treatment separately by using a Fisher exact test and a Mann-Whitney test.
RESULTS
: 206 patients with fixed retention failure were included, 169 in the mandibular and 74 in the maxillary jaws. Significant correlations were observed between retention failure in the mandibular jaws and mandibular arch length discrepancy ( = 0.010), post-treatment growth pattern ( = 0.041), nail biting ( < 0.001) and abnormal tongue function ( = 0.002). Retention failure in the maxillary jaws was more frequent in patients with IPR in the mandibular jaws ( = 0.005) and abnormal tongue function ( = 0.021).
CONCLUSIONS
: This study suggests a correlation between fixed retention failure and parafunctional habits, such as nail biting and abnormal tongue function. Prospective studies with larger study populations could further confirm these results.
PubMed: 37649417
DOI: 10.4041/kjod23.012 -
Cureus Jan 2024Background and objective The occipital spur (OS) can be described as an abnormal elongation of the external occipital protuberance (EOP); its etiology is...
Background and objective The occipital spur (OS) can be described as an abnormal elongation of the external occipital protuberance (EOP); its etiology is multifactorial and may involve biomechanical, immunological, and/or genetic factors. This study aimed to determine the frequency and characteristics of elongated EOP or OS as well as the relationship of OS with occlusion in a group of Turkish dental patients. Materials and methods Lateral cephalometric radiographs of 1925 patients taken in 2022 were retrospectively analyzed. The frequency, types, and dimensions of OS were determined based on gender and age groups. Molar occlusion and incisal bite were also evaluated. Results Of the 1925 patients, 679 were males and 1246 were females. The mean age of the cohort was 18.17 ±5.03 years (range: 4-61). OS was detected in 483 (25.1%) patients and was more common in males (p<0.001); 133 (27.5%) of the OSs were flat, 247 (51.1%) crest, and 103 (21.3%) spin type. The incidence of OS increased depending on age groups (p<0.001). There was no statistically significant association between OS presence and molar occlusion (p>0.05). However, a statistically significant association was observed between anterior incisal bite (p=0.001) and OS presence. There was a statistically significant difference in terms of OS sizes in males and females; the sizes of OS were larger in males than in females (length: p<0.05, base and thickness: p<0.001). Conclusions The frequency of OS was quite high in our cohort; it was more common and of larger size in males and older age groups. The most common type was the crest type. While there was no statistically significant association between OS frequency and molar occlusion, there was a significant relationship with incisal bite. The frequency of OS was highest in people with anterior crossbite.
PubMed: 38327918
DOI: 10.7759/cureus.51827