Bitter taste receptor TAS2R38 is expressed in the respiratory tract and can respond to quorum-sensing molecules produced by pathogens, stimulating the release of nitric oxide, with biocidal activity. ...TAS2R38 presents two main high-frequency haplotypes: the "taster" PAV and the "non-taster" AVI. Individuals carrying the AVI allele could be at greater risk of infections, including SARS-CoV-2. The aim of this study was to assess the frequency of PAV and AVI alleles in COVID-19 patients with severe or non-severe symptoms compared to healthy subjects to further corroborate, or not, the hypothesis that the PAV allele may act as a protecting factor towards SARS-CoV-2 infection while the AVI one may represent a risk factor. After careful selection, 54 individuals were included in the study and underwent genetic analysis and PROP phenotype assessment. Our investigation could not point out at a significant relationship between single nucleotide polymorphisms responsible for PROP bitterness and presence/severity of SARS-CoV-2 infection, as previous studies suggested. Our results uncouple the direct genetic contribution of rs10246939, rs1726866 and rs713598 on COVID-19, calling for caution when proposing a treatment based on TAS2R38 phenotypes.
Purpose
The myofunctional treatment (MFT) is a conventional therapy in the treatment of oral disease like atypical swallowing (AS). Functional (standardized surface electromyographic analysis—ssEMG) ...and clinical (“orofacial muscular evaluation with score” protocol—OMES) analyses were conducted to detect the effects of MFT (10 weeks session) in a group of patients with AS.
Methods
ssEMG was performed to analyze the activity of masseter (MM), temporalis (TA), and submental (SM) muscles before (T1) and after (T2) the MFT in a group of 15 patients. OMES was completed at the same timepoints. A Student-t test was carried out to detect differences between T1 and T2 for ssEMG data, and a signed RANK test was used for OMES ones. One-way ANOVA variance test was performed to detect any differences between the different couples of muscles at each timepoint.
Results
After MFT, patients showed a shorter duration of the whole act of swallowing (
p
< .0001), higher intensity of the SM activity (
p
< .01) than at T1. At T2 masticatory muscles showed lower values for the activation index (ANOVA,
p
< .0001) and for the spike position (ANOVA,
p
< .01) than SM. The OMES protocol showed a significant increase for the total evaluation score (
p
< .01), appearance-posture (
p
< .01) and functions (
p
< .001).
Conclusions
MFT permits a shortening of the muscular activation pattern and an increase in SM activity.
The improvement of oral functionalities is possible and identifiable thanks to the use of standardized protocols.
Background and Objectives
Within the same surgical procedure, a great variability on achievement of clinical outcomes exists and may be associated to different molecular factors related to tissue ...healing. The aim of the present study was to assess the distribution of clinical success separately in regenerative therapy (REG) and open flap debridement (OFD) to evaluate if factors related with healing of epithelium, connective tissue and bone may be associated to the clinical outcome within each surgical procedure.
Material and Methods
Sixteen patients underwent periodontal REG and nine patients underwent OFD. Periodontal wound fluid was collected at baseline, 3–5, 7, 14 and 21 d after surgery, and expression of wound healing proteins was assessed. Pocket depth and clinical attachment level were taken at baseline and at 6 mo of follow‐up. Percentage pocket depth reduction and percentage clinical attachment level gain were computed. Patients were regarded as better or worse responders depending on their percentage pocket depth reduction or percentage clinical attachment level gain.
Results
Higher percentage of better responders was observed in the REG group (68.7%) compared to the OFD group (22.2%). At 21 d, no difference in the profile of most of the proteins emerged, with two exceptions, both regarding REG treatment. Bone morphogenetic protein‐7 tended to increase in better responders and to decrease in worse responders. Matrix metalloproteinase‐1 increased in worse responders and remained substantially unchanged in better responders.
Conclusion
Local expression of matrix metalloproteinase‐1 and bone morphogenetic protein‐7 during wound healing is associated with the clinical performance of periodontal regenerative surgery. The use of local biomarkers offers the potential for real‐time assessment of the periodontal healing process.
summary The assessment of bite forces on healthy single tooth appears essential for a correct quantification of the actual impact of single implant oral rehabilitations. In the present study, a new ...single tooth strain‐gauge bite transducer was used in 52 healthy young adults (36 men, 16 women) with a complete permanent dentition. The influences of tooth position along the dental arch, of side, and of sex, on maximum bite force were assessed by an anova. No significant left–right differences were found. On average, in both sexes the lowest bite force was recorded on the incisors (40–48% of maximum single tooth bite force), the largest force was recorded on the first molar. Bite forces were larger in men than in women (P < 0·002), and increased monotonically along the arch until the first or second permanent molar (P < 0·0001). The present data can be used as reference values for the comparison of dental forces in patients.
Summary
Swallowing is a muscular activity that occurs both after mastication and spontaneously as a result of saliva accumulation. Spontaneous saliva swallowing occurs about every 2 minutes. ...Comprehension of its functional mechanisms is relevant to assess their modification in clinical situations. A standardised surface electromyographical (ssEMG) protocol for the evaluation of this muscle activity is lacking. Aims of the present study are: (i) to determine the reproducibility of a ssEMG protocol for the evaluation of the oral phase of saliva swallowing and (ii) to evaluate the activity of masseter (MM), anterior temporalis (TA), submental muscles (SM) to draw a reference model of swallowing. Standardised surface electromyographical activity of MM, TA and SM during swallowing of saliva spontaneously accumulated was recorded in 20 healthy participants. Functional indexes including symmetry (POC), recruitment (Impact), duration of activation of each couple of muscles and of the whole exercise, position, intensity of the spike were computed. Inter‐ and intra‐appointment reliabilities were assessed and method errors calculated. Descriptive statistics, sex‐ and muscles‐related comparisons were carried out. Standardised surface electromyographical assessment of MM, TA and SM muscles was reliable. A high inter‐individual variability was found. Percentage overlapping coefficient (POC) values were close to 80% for TA and SM, higher than for MM (P < .001). Impact values ranged between 16.4% and 30.7%, and differences were found between muscles (P < .001). The global muscle activity during swallowing lasted between 1.5 and 1.8 seconds. For each couple of muscles, the duration of activation ranged between 0.7 and 1.6 seconds and muscles‐related differences were found (P < .001). The spike of activation for each couple of muscle ranged between 35.7% and 44.2% of the duration. The protocol was reliable and intra‐participants repeatable measures can be carried out. Due to the high inter‐participants variability, further analyses are needed to draw a model of muscular activity.
Structured
Introduction
The development of skeletal structures (cranial base, upper and lower) and upper airways spaces (oropharyngeal and nasopharyngeal) of the skull has always been an issue of ...great interest in orthodontics. Foetal MRI images obtained as screening exam during pregnancy can help to understand the development of these structures using a sample cephalometric analysis.
Material and Methods
A total of 28 MRI images in sagittal section of foetuses from 20th to 32th weeks of gestation were obtained to dispel doubts about the presence of skeletal malformations. Cephalometric measurements were performed on MRI T2‐dependent images acquired with a 1.5 T scanner. The Software Osirix 5 permits to study sagittal and vertical dimensions of the skull analysing linear measurements, angles and areas of the skeletal structures.
Results
Vertical and sagittal dimension of cranial base, maxilla and mandible grow significantly (P < .01) between the second and third trimester of gestational period as well as nasopharyngeal and oropharyngeal spaces (P < .05). High correlation between the development of anterior cranial base and functional areas devoted to speech and swallow is demonstrated (r: .97).
Conclusions
The development of craniofacial structures during foetal period seems to show a close correlation between skeletal features and functional spaces with a peak between the second and third trimester of gestation. MRI images result helpful for the clinician to detect with a sample cephalometric analysis anomalies of skeletal and functional structures during prenatal period.
It has been suggested that atypical swallowing (AS) may negatively influence the skeletal and alveolar development, but its specific effects are still unclear. The aim of this work is to compare the ...cephalometric characteristics of children and adolescents with and without AS.
Study design: Case-control retrospective cross-sectional study. One hundred patients with (AS group) and 100 patients without AS (control group, C) were retrospectively selected. Their cephalometric data before orthodontic treatment were compared using a 3-way ANOVA variance test to detect any differences between groups considering: the type of swallowing (AS vs C); whether or not the second dentition was completed (SDC vs SDNC); and the gender (males-M and females-F). In addition, a Student-t test for unpaired data was carried out to detect differences between M and F within the AS and C groups.
When compared to the controls, AS patients showed a significantly decreased SNB angle (p<.01), increased ANB and SN^Go. Me angles (p<.0001), increased overjet and lower facial height (p<.01), decreased overbite (p<.0001), and increased proclination of the upper incisors. AS-SDC patients also showed significantly increased alveolar length. Within the AS and C groups, skeletal and alveolar measurements were larger in males, with higher significance in the C group, suggesting a different trend of growth in AS patients.
AS seems to affect the skeletal growth causing mandibular clockwise rotation, skeletal Class II, open bite and incisor proclination. To compensate for these effects, an increase in alveolar growth together with molar eruption seems to be induced.
Summary
This study evaluated the electromyographic (EMG) characteristics of masticatory muscles in patients with fixed implant‐supported prostheses according to All‐on‐Four® principles and in control ...healthy dentate subjects. Twenty‐six subjects aged 50–74 years were examined. Eighteen were edentulous and had been successfully rehabilitated with (i) mandibular All‐on‐Four® implant‐supported fixed prostheses and maxillary complete dentures (10 patients) and (ii) mandibular and maxillary All‐on‐Four® implant‐supported fixed prostheses (eight patients). Eight reference subjects had natural dentition. Surface EMG recordings of the masseter and temporalis muscles were performed during maximum voluntary teeth clenching and during unilateral gum chewing. All values were standardised as percentage of a maximum clenching on cotton rolls. During clenching, a good global neuromuscular equilibrium was found in all participants. During chewing, all groups had similar values of working‐side muscle activities and of chewing frequency. No significant differences in the analysed EMG parameters were found between the patients with mandibular and maxillary All‐on‐Four® implant‐supported prostheses and the reference subjects. In contrast, standardised pooled muscle activities and standardised muscular activities per cycle were larger in patients with a maxillary removable prosthesis than in control subjects (Kruskal–Wallis test, P < 0·01). Also, patients wearing a complete maxillary denture showed a poor neuromuscular coordination with altered muscular pattern and lower values of the index of masticatory symmetry than dentate control subjects (P < 0·01). EMG outcomes suggest that All‐on‐Four® implant‐supported prostheses may be considered a functionally efficient treatment option for the rehabilitation of edentulous patients with reduced residual bone volume.
Summary Surface electromyography (EMG) allows the quantification of the occlusal equilibrium in dysfunctional patients, for instance in those with temporomandibular disorders (TMD). Fourteen patients ...(ten women, four men) with internal derangement type I were selected among the TMD patients referred to a private practice in Milan. A stabilization splint with posterior contacts was made for each patient. To verify the static neuromuscular equilibrium of occlusion, EMG activity of left and right temporal and masseter muscles was recorded in all patients and the activity (ratio between the activities of the temporal and masseter muscles) index was computed over a maximum voluntary clench test of 3 s. Muscular waveforms were also analysed by computing a percentage overlapping coefficient (POC, an index of the symmetric distribution of the muscular activity determined by the occlusion). The total electrical activity was measured by calculating the area under the entire muscular waveforms. In all patients EMG was performed just before and immediately after the insertion of the splint and data were compared by paired Student's t‐tests. Overall, the splint reduced the electrical activity of the analysed muscles (P < 0·005) and made it more equilibrated both between the left and right side (larger symmetry in the masseter muscle POC, P < 0·05) and between the temporal and masseter muscles (activity index, P < 0·01).
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