Correlation between oral muscle pressure and malocclusion in mixed dentition: a cross-sectional study.

OBJECTIVE: To investigate the relationship between oral muscle pressure and malocclusion in the mixed dentition. MATERIALS AND METHODS: Maximum tongue, lip and cheek pressure was measured using the Iowa Oral Performance Instrument (IOPI) in 3 patient cohorts: patients with (1) posterior crossbite, (2) class II relationship and (3) a control group of patients without malocclusion. Linear models were used to compare the mean differences in muscle pressure between groups, with correction for age and gender. The imbalance between lips and tongue and between lips and cheeks was calculated by the Delta z-scores of each group. RESULTS: A total of 146 participants were included, 46 (mean age 8.71±0.85), 41 (mean age 11.74±1.17) and 35 (mean age 10.71±1.92) in groups 1, 2 and 3 respectively. Patients with malocclusion showed significantly higher lip and lower cheek pressure and imbalance favouring the lips over the tongue compared to controls. Class II,1 patients showed significantly higher tongue pressure than Class II,2. No differences were found in muscle pressure or imbalance between crossbite and Class II nor between crossbite types. CONCLUSION AND CLINICAL RELEVANCE: These findings suggest that oral muscle pressure may be associated with malocclusion. This highlights the importance of functional diagnosis and its implications on the prevention and treatment of malocclusion, as well as on orthodontic stability.

Reproducibility of Buccal Gingival Profile Using a Custom Pick-Up Impression Technique: A 2-Year Prospective Multicenter Study.

PURPOSE: The aim of this study was to transfer the provisional restoration emergence profile to the final implant-supported restoration and to buccal gingival margin (BGM) stability after 2 years of function. MATERIALS AND METHODS: A total of 33 patients were recruited for treatment of single gaps by means of 33 implant-supported restorations. Fixed provisional crowns were screwed to the fixture and adjusted until the complete peri-implant soft tissue maturation was achieved. After 12 weeks, a second fixture impression was taken by means of a pick-up customization technique in order to transfer the clinical aspect of the peri-implant soft tissues to the master cast. A definitive restoration was delivered. A standardized method from digital photographs was used to assess the gingival margin modification (BGM) from the provisional (P) to the definitive prosthesis installation at baseline (D0), and after 1 (D1) and 2 years (D2) of function. Also, marginal bone loss (MBL) was calculated after 1 (D1) and 2 years (D2) of definitive restoration function. RESULTS: The BGM index at the time of the final restoration installation (D0) was 0.12 ± 0.33 mm if compared with the BGM position of the provisional restoration (P); it was of 0.12 ± 0.46 mm after 1-year of follow-up (D1) and of 0.31 ± 0.21 after 2 years of function (D2). No significant difference was calculated between measurements in different follow-up visits (p > 0.05). No significant MBL was measured between the baseline (D0) and the 1-year follow-up (p = 0.816) with a mean MBL value of 0.2 ± 0.1 mm. Similar result was calculated after 2 years (p = 0.684) with a mean MBL value of 0.3 ± 0.2. CONCLUSION: A modified impression pick-up may be helpful to reproduce the gingival margin position from the provisional to the definitive restoration. Moreover, the gingival zenith position during the follow-up period seemed to be stable. CLINICAL SIGNIFICANCE: The modification of the standard impression pick-up technique may contribute to reproducing a natural emergence profile of esthetic implant prosthetic restorations (from the provisional to the definitive restoration.) With this technique, implant soft tissues stability around CAD-CAM (computer aided design-computer aided manufacturing) abutments can be easily obtained, and the customized abutment shape may better support the scalloped peri-implant soft tissues architecture, especially in anterior areas.

Response characteristics of pruriceptive and nociceptive trigeminoparabrachial tract neurons in the rat.

We tested the possibility that the trigeminoparabrachial tract (VcPbT), a projection thought to be importantly involved in nociception, might also contribute to sensation of itch. In anesthetized rats, 47 antidromically identified VcPbT neurons with receptive fields involving the cheek were characterized for their responses to graded mechanical and thermal stimuli and intradermal injections of pruritogens (serotonin, chloroquine, and ß-alanine), partial pruritogens (histamine and capsaicin), and an algogen (mustard oil). All pruriceptive VcPbT neurons were responsive to mechanical stimuli, and more than half were additionally responsive to thermal stimuli. The majority of VcPbT neurons were activated by injections of serotonin, histamine, capsaicin, and/or mustard oil. A subset of neurons were inhibited by injection of chloroquine. The large majority of VcPbT neurons projected to the ipsilateral and/or contralateral external lateral parabrachial and Kölliker-Fuse nuclei, as evidenced by antidromic mapping techniques. Analyses of mean responses and spike-timing dynamics of VcPbT neurons suggested clear differences in firing rates between responses to noxious and pruritic stimuli. Comparisons between the present data and those previously obtained from trigeminothalamic tract (VcTT) neurons demonstrated several differences in responses to some pruritogens. For example, responses of VcPbT neurons to injection of serotonin often endured for nearly an hour and showed a delayed peak in discharge rate. In contrast, responses of VcTT neurons endured for roughly 20 min and no delayed peak of firing was noted. Thus the longer duration responses to 5-HT and the delay in peak firing of VcPbT neurons better matched behavioral responses to stimulation in awake rats than did those of VcTT neurons. The results indicate that VcPbT neurons may have important roles in the signaling of itch as well as pain.

Validity and reliability of a protocol of orofacial myofunctional evaluation for patients with obstructive sleep apnea.

There is no standardized protocol for the clinical evaluation of orofacial components and functions in patients with obstructive sleep apnea. The aim of this study was to examine the validity, reliability, and psychometric properties of the Expanded Protocol of Orofacial Myofunctional Evaluation with Scores (OMES-expanded) in subjects with obstructive sleep apnea. Patients with obstructive sleep apnea and control subjects were evaluated, and the validity of OMES-expanded was tested by construct validity (i.e. the ability to discriminate orofacial status between apneic and control subjects) and criterion validity (i.e. correlation between OMES-expanded and a reference instrument). Construct validity was adequate; the apneic group showed significantly worse orofacial status than did control subjects. Criterion validity of OMES-expanded was good, as was its reliability. The OMES-expanded is valid and reliable for evaluating orofacial myofunctional disorders of patients with obstructive sleep apnea, with adequate psychometric properties. It may be useful to plan a therapeutic strategy and to determine whether the effects of therapy are related to improved muscle and orofacial functions.

THE MASTICATORY SYSTEM OF THE OBESE: CLINICAL AND ELECTROMYOGRAPHIC EVALUATION.

UNLABELLED: Masticatory performance is determined not only through the speed of mastication, or by the quantity of food ingested; it also depends on the structures and functional integration of the stomatognathic system (SS). OBJECTIVES: This study investigated differences in the SS and orofacial motricity between obese and normal--weight women. METHOD: A total of 18 obese women, with an average age of 28 ± 7.3 years and an average body mass index (BMI) of 37.4 ± 5.1 Kg/m2, and 18 normal--weight women, with an average age of 26 ± 7.6 years and an average BMI of 20.7 ± 1.8 kg/m2, took part in the study. During the speech therapy evaluation, chewing, the number of chewing strokes, and swallowing were observed. The posture, mobility and tonus of lips and tongue, morphology, mobility and tonus of cheeks were designated as normal or altered. The electrical activity of the anterior temporalis, the masticatory muscle was evaluated for both groups using surface electromyography (EMG), which was expressed in microvolts (pV) and registered as Root Mean Squares. RESULTS: Significant differences were found between the two groups in clinical evaluation. In surface EMG, the obese group showed asymmetry of electrical activity of the anterior temporalis. CONCLUSION: This study suggests that speech therapist investigation of the SS should be combined with interdisciplinary obesity management.

A quantitative evaluation method of skin texture affected by skin ageing using replica images of the cheek.

OBJECTIVE: Skin texture is a fine structure of skin surface where the hill and furrow were crossed to form a star shape. This study was performed to establish a quantitative evaluation method of skin texture affected by skin ageing using replica images of the cheek. METHODS: After producing replicas of the left cheek areas of 80 female subjects, representative replica images were chosen to establish six-level facial skin texture index. Using this new index, skin texture of different-aged subjects was visually assessed by multiple examiners. The number of star configurations was also analysed using the same replica images. Other factors contributing to skin texture, such as skin elasticity, roughness, dermal density, moisture and gloss, were also analysed. RESULTS: The concordance between skin texture scores evaluated by three researchers was high (0.896), and there was a high correlation between skin texture score and age (r = 0.642). The number of star configurations showed high correlations with skin texture scores (r = 0.753) and with age (r = 0.776). Skin texture scores were highly correlated with skin roughness and dermal density, but not with moisture, gloss and elasticity. CONCLUSION: This study suggests that visual grading of skin texture score based on new facial skin texture index and quantification of star configurations will be useful in evaluating skin ageing.

Oral motor movements and swallowing in patients with myotonic dystrophy type 1.

Oropharyngeal dysphagia and esophageal motility disorders were found to be the most important causes of aspiration pneumonia in patients with myotonic dystrophy. The purpose of this report was to evaluate clinical characteristics of the oral motor movements and swallowing of individuals with myotonic dystrophy type 1 (DM1) using a standardized clinical protocol and surface electromyography (sEMG). Participants were 40 individuals divided in two groups: G1 composed of 20 adults with DM1 and G2 composed of 20 healthy volunteers paired by age and gender to the individuals in G1. Statistical analysis included one-way ANOVA with two factors for within- and between-group comparisons and Bonferroni correction for multiple comparisons. Patients with DM1 presented deficits in posture, position, and mobility of the oral motor structures, as well as compromised mastication and deglutition. The sEMG data indicated that these patients had longer muscle activations during swallowing events. The longer duration of sEMG in the group of patients with DM1 is possibly related to myotonia and/or incoordination of the muscles involved in the swallowing process or could reflect a physiological adaptation for safe swallowing.

Validity of the 'protocol of oro-facial myofunctional evaluation with scores' for young and adult subjects.

UNLABELLED: The aims of this study were to analyse the validity, sensitivity and specificity of the protocol of oro-facial myofunctional evaluation with scores (OMES) for oro-facial myofunctional disorder (OMD) diagnosis in young and adult subjects. Eighty subjects were examined. The OMES was validated against the Nordic orofacial test-screening (NOT-S) protocol (criterion validity) (Spearman correlation test). The construct validity was tested by analysis of the ability of the OMES (i) to differentiate healthy subjects (n = 22) from temporomandibular disorder (TMD) patients (n = 22), which frequently have OMD (Mann-Whitney test) and (ii) to measure the changes that occurred in a subgroup with TMD between the period before and after oro-facial myofunctional therapy (T group, n = 15) (Wilcoxon test). Two speech therapists trained with the OMES participated as examiners (E). There was a statistically significant correlation between the OMES and NOT-S protocols, which was negative because the two scales are inverse (r = -0·86, P < 0·01). There was a significant difference between the healthy and TMD subjects regarding the oro-facial myofunctional status (OMES total score, P = 0·003). After therapy, the T group showed improvement in the oro-facial myofunctional status (OMES total score, P = 0·001). Inter- and intra-examiner agreement was moderate, and the reliability coefficients ranged from good to excellent. The OMES protocol presented mean sensitivity and specificity = 0·80, positive predictive value = 0·76 and negative predictive value = 0·84. CONCLUSION: The OMES protocol is valid and reliable for clinical evaluation of young and adult subjects, among them patients with TMD.

Association between intraoral pressure and molar position and inclination in subjects with facial asymmetry.

Although it has been suggested that an imbalance in buccolingual pressure may play a role in dental compensation of the molars and asymmetry in the mandibular dental arch in subjects with facial asymmetry, it is still unclear whether buccolingual pressure is associated with this phenomenon. Thus, the purpose of this study was to test the null hypothesis that there are no differences in cheek and tongue pressure between the shifted and non-shifted sides in 12 (8 females and 4 males, mean age: 24.9 years) subjects with facial asymmetry defined as 4 mm or more deviation of the midline in the mandibular incisors. The resting buccolingual pressure on the bilateral mandibular first molars was measured simultaneously using four miniature pressure sensors. Moreover, a postero-anterior (PA) cephalogram was used to determine the buccolingual positions and the inclination of the mandibular first molars. Wilcoxon t-, Kruskal-Wallis H-, and Mann-Whitney U-tests and Spearman correlation coefficient by rank were used for statistical analysis. Significance was set at P < 0.05. Cheek pressure was significantly greater on the shifted than that on the non-shifted side, while tongue pressure on the shifted side was significantly less than that on the non-shifted side. On the other hand, tongue/cheek pressure ratio on the shifted side was significantly less than that on the non-shifted side. There were significant differences between the shifted and non-shifted sides in the buccolingual positions and inclination of the mandibular first molars. Regardless of the side, there were significant negative correlations between the buccolingual position of the mandibular first molars and cheek pressure and significant positive correlations between the buccolingual position of the mandibular first molars and tongue/cheek pressure ratio. There were also significant negative correlations between tongue/cheek pressure ratio and inclination of the mandibular first molars on both the shifted and the non-shifted sides. Thus, the present findings reject the null hypothesis. The imbalance in buccolingual pressure in subjects with facial asymmetry appears to be related to dental compensation of the molars and mandibular asymmetry.

Comparison of oral mucosal pH values in bulimia nervosa, GERD, BMS patients and healthy population.

OBJECTIVES: The aim of this study was to compare the oral mucosal pH in healthy individuals to patients with gastroesophageal reflux disease (GERD), Bulimia nervosa (BN) and burning mouth syndrome (BMS). SUBJECTS AND METHODS: Using a flat pH meter sensor, pH levels were established in eight mucosal sites in 26 healthy individuals, 26 GERD patients, 22 BN patients and 29 BMS patients. RESULTS: A significantly lower pH was found in the BN and GERD groups (6.38 ± 00.45, 6.51 ± 0.32 respectively, P < 0.05) and a higher, but non-significant, pH level in the BMS group (7.01 ± 0.34, P > 0.05) compared with the control (C) group (6.82 ± 0.33). CONCLUSIONS: BMS patients showed no pH differences from C group. The mucosa of BN and GERD patients was significantly acidic relative with controls; thus this simple technique may serve as a diagnostic tool for identifying gastro-esophageal conditions.

Influence of subcutaneous adipose tissue mass on dermal elasticity and sagging severity in lower cheek.

BACKGROUND: Subcutaneous adipose tissue lies just beneath the dermal layer, but the interaction between the two is not well understood. Recently, we showed that the subcutaneous adipose layer affects dermal properties in an obese rodent model. OBJECTIVE: To explore the influence of the subcutaneous adipose layer on dermal properties and morphology in humans. METHODS: Subcutaneous adipose mass was measured by ultrasound using a Prosound alpha 5, dermal elasticity was measured using an in vivo suction skin elasticity meter (Cutometer MPA 580, and sagging severity were evaluated morphologically using photograph-based grading criteria at the lower cheek in 70 Japanese female volunteers (age; 31-59, BMI; 17.1-36.2). The correlations among the results were examined. RESULTS: Thickness of the subcutaneous adipose layer was significantly and negatively correlated with dermal elasticity parameters, i.e., elastic deformation, elastic deformation recovery, extensibility, total deformation recovery, ratio of viscoelasticity to elastic distention and overall elasticity, including creep and creep recovery. Furthermore, we investigated their influence on facial morphology, such as sagging. The subcutaneous adipose mass was significantly and positively correlated with sagging severity at the lower cheek (R=0.442, P<0.001), and there was a significant negative correlation between dermal elasticity and sagging severity (R=-0.358, P<0.01). CONCLUSION: These results indicate that increment of subcutaneous adipose mass impairs dermal elasticity, which in turn exacerbates sagging severity.

An erythematous facial rash.

Two months of treatment with doxycycline provided no improvement. A biopsy of the patient's cheek led to a proper diagnosis.

Detection of temporal lobe spikes: comparing nasopharyngeal, cheek and anterior temporal electrodes to simultaneous subdural recordings.

OBJECTIVE: To compare nasopharyngeal (NP), cheek and anterior temporal (AT) electrodes for the detection yield and localization of interictal spikes in temporal lobe epilepsy. METHODS: In patients evaluated for epilepsy surgery with subdural electrocorticography electrodes, we simultaneously recorded NP, cheek and AT electrodes. Two observers identified spikes in EEG traces and marked in which channels they occurred. Interobserver agreement was calculated using Cohen's kappa. For localization, data-sets with high interobserver agreement (kappa-value 0.4) were evaluated. The subdural distribution of NP and AT spikes was mapped. RESULTS: Seven patients were included, six were analyzed for localization. Only 1.5% of spikes recorded by cheek electrodes were not seen on temporal leads, while 25% of NP spikes were not seen on either. Spikes only recorded by NP electrodes had mesiobasal, while AT spikes had lateral temporal distribution. CONCLUSIONS: NP electrodes can increase EEG spike detection rate in temporal lobe epilepsy and are more useful than cheek electrodes. Spikes that are seen only on NP electrodes tend to be mesiobasal temporal lobe spikes. SIGNIFICANCE: Adding NP electrodes to scalp EEG can aid interictal spike detection and source localization, especially in short recordings like MEG-EEG.

Changes in lips, cheeks and tongue pressures after upper incisor protrusion in Class II division 2 malocclusion: a prospective study.

BACKGROUND: The etiology of Class II division 2 (CII/2) malocclusion focuses on heredity; however lip, cheek, and tongue pressures that are associated with the environmental effect are considered to have an effect. The aim of this study was to evaluate the relation between perioral pressures and the upper incisor inclination in CII/2 malocclusion. METHODS: Twenty patients (8 females, 12 males; mean age 10.29 ± 0.90 years) with CII/2 malocclusion were included in the study group, and 15 patients (5 females, 10 males; mean age 10.56 ± 1.06 years) with Class I malocclusion were included. The upper incisors were protruded with a utility arch (0.016 × 0.022 in. blue elgiloy wire). Perioral pressure assessment was made with the Iowa Oral Pressure Instrument. Upper lip pressure, lower lip pressure, vertical lip pressure, left-right buccal pressures, swallowing, and maximum tongue pressures were measured. Repeated measure ANOVA was used to test the intragroup differences. Intergroup comparisons were made using two-way repeated measure ANOVA with Bonferroni correction. Relationships between the variables were analyzed using rank correlation (Spearman's rho). The significance for all statistical tests was predetermined at p < 0.05. RESULTS: A significant change occurred in the upper lip pressure, lower lip pressure, and vertical lip pressure; however, significant difference was not found between the groups. Upper lip pressure increased significantly in both groups. In the CII/2 group, lower lip pressure increased after protrusion and decreased after retention, while vertical lip pressure decreased and then increased significantly. Left buccal pressure changes between the groups were not parallel. Right buccal pressure, swallowing, and maximum tongue pressure changes were not statistically significant. Statistically significant correlation was found between U1-NA (mm) and vertical lip pressure (r -0.467). CONCLUSIONS: In the CII/2 group, upper lip pressure increased only in retention. Lower lip pressure increased and vertical lip pressure decreased after protrusion. Nevertheless, these changes did not remain stable after the retention period. The difference between groups was not statistically significant at the end of retention.

Somatosensory Feedback to the Cheek During Virtual Visual Feedback Therapy Enhances Pain Alleviation for Phantom Arms.

BACKGROUND: Patients who suffer from phantom limb pain can perceive tactile stimuli applied to the cheek on their affected side as if it were coming from their phantom limb, a phenomenon called "referred sensation." OBJECTIVES: To investigate the analgesic effect produced by tactile feedback provided to the cheek during neurorehabilitation using visual feedback. METHODS: Nine participants with phantom upper limb pain performed virtual reality neurorehabilitation exercises in which they repeatedly touched a target object with a virtual representation of their affected limb. We applied tactile feedback to their cheek when their virtual affected limb touched a virtual object (Cheek Condition). We also included 2 control conditions where tactile feedback was either applied to their intact hand (Intact Hand Condition) or not applied at all (No Stimulus Condition). We evaluated pain intensity on an 11-point rating scale and pain quality using the short-form McGill Pain Questionnaire before and after each rehabilitation condition. RESULTS: The median pain-reduction rate in the Cheek Condition (33.3 ± 24.4%) was significantly higher than in the Intact Hand Condition (16.7 ± 12.3%) and the No Stimulus Condition (12.5 ± 13.5%; P < .05). Even patients who did not feel referred sensations reported significant pain reduction after the Cheek Condition. CONCLUSIONS: The analgesic effect of neurorehabilitative visual feedback during phantom limb movement is significantly improved by applying somatosensory feedback to the cheek on the affected side. Further studies are needed to extend these findings to objective pain measures and to elucidate the neural mechanisms that underlie the analgesic effect.

Radiation-induced osteosarcoma of the maxilla.

Radiation-induced sarcomas are well-known though uncommon potential late sequelae of radiation therapy. We report irradiation-induced osteosarcoma involving the maxilla following treatment of nasopharyngeal carcinoma in a 44-year-old man who presented with painful cheek swelling. Radiographs and computed tomography showed a large destructive lesion of the left maxilla. Diagnosis of osteosarcoma was confirmed by excision biopsy.

Crossed buccofacial apraxia.

The cerebral hemisphere contralateral to the preferred hand is generally dominant for learned representational motor acts, including those involving buccofacial muscles. It is generally also language-dominant. This buccofacial apraxia has, with rare exceptions, been associated with left hemispheric lesions in right-handers. We describe two patients with severe buccofacial apraxia caused by large middle cerebral artery territory infarcts in the hemisphere ipsilateral to the preferred hand and nondominant for language. Neither patient had aphasia or major limb apraxia. Computed tomographic scans in the first patient and neuropathologic examination in the second failed to reveal an abnormality of the hemisphere contralateral to the preferred hand. Hence, in some individuals, the hemisphere controlling skilled representational buccofacial movements may not be the one that is dominant either for handedness or for language.

The influence of oxidative stress on permeability of capillary vessels in the cheek pouch of hamsters with alloxan-induced diabetes.

BACKGROUND: The aim of the study was to assess the influence of oxidative stress on the increase of permeability of capillary vessels in animals with alloxan-induced diabetes. MATERIAL AND METHODS: The studies were performed in microcirculation system of hamster cheek pouch. After the blockade of histamine receptors and administration of diamine oxidase (DAO) and histamine into circulation fluorescein angiography was done. In addition, the influence of superoxide dismutase, aminoguanidine (DAO inhibitor) and trascolan (protease inhibitor) on vascular permeability caused by superoxide radical generation in DAO/histamine system was assessed. RESULTS: The number of extravasal leakages in the group receiving HA and DAO was significantly higher (p < 0.001) than in the groups receiving potential vascular "sealers", e.g. SOD, aminoguanidine or trascolan. In the group receiving aminoguanidine the number of leakages was significantly lower (p < 0.05) compared to the group receiving SOD or trascolan. CONCLUSIONS: The protective effect of aminoguanidine, superoxide dismutase or trascolan decreasing the vascular permeability, suggests that the increased vascular permeability is a result of superoxide radical generation by diamine oxidase.

Effects of different pacifiers on the primary dentition and oral myofunctional strutures of preschool children.

PURPOSE: The aim of this study was to evaluate the characteristics of the dental arches and some oral myofunctional structures in 36- to 60-month-old children who sucked a pacifier or did not have this habit. METHODS: Sixty-one children were divided into 3 groups: (1) those who never sucked a pacifier, (2) those who exclusively sucked a physiological pacifier, and (3) those who exclusively sucked a conventional one. A clinical examination was performed on the children to observe the relationship between the arches and their width, as well as the following oral myofunctional structures: lips, tongue, cheeks, and hard palate. RESULTS: Statistical analysis showed that: (1) the use of both ytpes of pacifiers led to anterior open bite (prevalence of 50% in both groups; P = . 001), (2) posterior crossbite was present only on children who had a pacifier-sucking habit, (3) the mean oveqrjt was greater on children who sucked physiological (3.6 mm) or conventional (3.7 mm) pacifiers when compared to those with no sucking habits (1.3 mm; P = .001), (4) intercanine distance of the upper arch was significantly smalelr on children who sucked pacifiers (29.6 mm in the physiological group and 29.2 mm in the conventional pacifier group) than those who did not (31.2 mm), and (5) the children who never sucked on a pacifier showed a higher prevalence of normality of cheek mobility (74%; P = .022) and hard palate shape (78%; P = .042). CONCLUSIONS: Children who sucked pacifiers, both conventional and physiological ones, showed higher prevalence of alterations in the relationship of the dental arches and orla myofunctional structures, when compared to those who never sucked a pacifier.