Efficacy of the transcutaneous electrostimulation in treatment dysfunctions of the TMJ associated with occlusion distortions.

BACKGROUND: The study evaluation of the effectiveness the method of electrostimulation in treatment TMJ associated with occlusion disorders with the use of a patches by the company "Aganyan''. METHODS: The study included 54 patients with temporomandibular dysfunction syndrome who had previously undergone endodontic dental treatment. In patients temporomandibular disorders (TMD) determined on the basis of Diagnostic criteria for temporomandibular disorders(DC/TMD).All patients had occlusion disorders due to errors after dental filling restoration. To diagnose the TMJ, a CT scan was used. The complex therapy also included therapy and with the use of a patches by the company "Aganyan''. The wearable patch includes a flexible substrate, a binder an adhesive layer, with an electrode foil attached to it. Patients applied one patch behind each TMJ. The patches were applied for eight hours every third day for three months. All the patients were given full-fledged endodontic treatment and restoration of the crown part, taking into account anatomical features. RESULTS: The dynamics of the complex treatment of patients diagnosed with TMJ dysfunction syndrome showed that after treatment, the clinical symptoms gradually decreased and disappeared at the end of treatment. CT scan a year after treatment showed a normal ratio of TMJ elements. Сomplex treatment was effective in 87% of patients, after 3-5 months gradually decreased pain, noise in the joints, restriction of opening and closing of the mouth disappeared. Patients recovered their chewing functions, psycho-emotional state. CONCLUSION: The results of the studies revealed a positive effects for the complex treatment dysfunctions syndrome TMJ the using the patches by the company "Aganyan" through electrical stimulation with low intensity.

Amoxicillin chewable tablets intended for pediatric use: formulation development, stability evaluation and taste assessment.

To cover the unpleasant taste of amoxicillin (250 mg), maize starch (baby food) and milk chocolate were co-formulated. The raw materials and the final formulations were characterized by means of Dynamic Light Scattering (DLS), Differential Scanning Calorimetry (DSC) and Fourier-Transform Infrared (FT-IR) spectroscopy. To evaluate the taste masking two different groups of volunteers were used, according to the Ethical Research Committee of the Aristotle University of Thessaloniki. The optimization of excipients' content in the tablet was determined by experimental design methodology (crossed D-optimal). Due to the matrix complexity, amoxicillin was extracted using liquid extraction and analyzed isocratically by HPLC. The developed chromatographic method was validated (%Recovery 98.7-101.3, %RSD = 1.3, LOD and LOQ 0.15 and 0.45 µg mL-1 respectively) according to the International Conference on Harmonization (ICH) guidelines. The physicochemical properties of the tablets were also examined demonstrating satisfactory quality characteristics (diameter: 15 mm, thickness: 6 mm, hardness <98 Newton, loss of mass <1.0%, disintegration time ∼25min). Additionally, dissolution (%Recovery >90) and in vitro digestion tests (%Recovery >95) were carried out. Stability experiments indicated that amoxicillin is stable in the prepared formulations for at least one year (%Recovery <91).

Dental microwear of a basal ankylosaurine dinosaur, Jinyunpelta and its implication on evolution of chewing mechanism in ankylosaurs.

Jinyunpelta sinensis is a basal ankylosaurine dinosaur excavated from the mid Cretaceous Liangtoutang Formation of Jinyun County, Zhejiang Province, China. In the present study, its dental microwear was observed using a confocal laser microscope. Jinyunpelta had steep wear facets that covered most of buccal surfaces of posterior dentary teeth. Observation of dental microwear on the wear facet revealed that scratch orientation varied according to its location within the wear facet: vertically (i.e. apicobasally) oriented scratches were dominant in the upper half of the wear facet, and horizontally (i.e. mesiolaterally) oriented ones were in the bottom of the facet. These findings indicated that Jinyunpelta adopted precise tooth occlusion and biphasal jaw movement (orthal closure and palinal lower jaw movement). The biphasal jaw movement was widely observed among nodosaurids, among ankylosaurids, it was previously only known from the Late Cretaceous North American taxa, and not known among Asian ankylosaurids. The finding of biphasal jaw movement in Jinyunpelta showed sophisticate feeding adaptations emerged among ankylosaurids much earlier (during Albian or Cenomanian) than previously thought (during Campanian). The Evolution of the biphasal jaw mechanism that contemporaneously occurred among two lineages of ankylosaurs, ankylosaurids and nodosaurids, showed high evolutionary plasticity of ankylosaur jaw mechanics.

Treatment with the essential amino acid L-tryptophan reduces masticatory impairments in experimental cerebral palsy.

Purpose Children with cerebral palsy (CP) often exhibit difficulties in feeding resulting from deficits in chewing. This study investigates the therapeutic potential of L-tryptophan (TRI) to reduce deficits in chewing in rats subjected to an experimental model of CP.Methods A total of 80 Wistar albino rats were used. Pups were randomly assigned to 4 experimental groups: Control Saline, Control TRI, CP Saline, and CP TRI groups. The experimental model of CP was based on the combination of perinatal anoxia associated with postnatal sensorimotor restriction of the hind limbs. TRI was administered subcutaneously during the lactation period. Anatomical and behavioral parameters were evaluated during maturation, including body weight gain, food intake, chewing movements, relative weight and the distribution of the types of masseter muscle fibers.Results The induction of CP limited body weight gain, decreased food intake and led to impairment in the morphological and functional parameters of chewing. Moreover, for a comparable amount of food ingested, CP TRI animals grew the most. In addition, supplementation with TRI improved the number of chewing movements, and increased the weight and proportion of type IIB fibers of the masseter in rats subjected to CP.Conclusion These results demonstrate that experimental CP impaired the development of mastication and that TRI supplementation increased masticatory maturation in animals subjected to CP.

Electromyographic analysis of stomatognathic muscles in elderly after hippotherapy.

The aging process affects the entire human body, including the stomatognathic system, and can trigger not only occlusal but also postural imbalances involving other muscular chains. Hippotherapy has been used to promote cervical, postural, and balance control in individuals with diverse impairments. The present study used electromyography to evaluate the masseter and temporal muscles in an elderly population pre- and post-hippotherapy. Participants included 17 individuals, mean age 66,5±7 years. Electromyographic recording of the bilateral masseter and temporal muscles was performed during the postural resting condition and activities that involved the active participation of these muscles in different conditions. The practitioner performed no other type of activity or exercise during the intervention because the objective is to evaluate the effect of the three-dimensional movement provided by the horse. Raw electromyographic data were tabulated using commercially available software (IBM® SPSS® Statistics 234.0) and subjected to statistical analysis, in which p ≤ 0.05 was considered to be statistically significant. Post-hippotherapy, there was lower electromyographic activity for the masseter and temporalis muscles in all the static mandibular tasks, with significant effect for time for the right temporal muscle (p = 0.038), the left temporal muscle (p = 0.028) and in the all dynamic mandibular tasks for the left temporal muscle (p = 0.025) and the left masseter muscle (p = 0.027). Hippotherapy promotes a reduction in the myoelectric activity of the masticatory muscles of elderly individuals.

Sauce it up: influence of condiment properties on oral processing behavior, bolus formation and sensory perception of solid foods.

Condiments are rarely consumed on their own. Although addition of condiments to carrier foods is known to affect oral processing behavior and sensory perception, an understanding of how different condiment properties impact oral processing behavior and sensory perception of solid carrier foods is lacking. This study aimed to understand the role of condiments varying in composition and/or rheological properties in bolus formation facilitation, and how they influence oral processing behavior and sensory perception of solid carrier foods. Two carriers (bread, cooked potato) were combined with mayonnaises differing in fat content and viscosity. Addition of mayonnaises changed bolus properties of solid carrier foods considerably (i.e. decreased bread firmness, increased potato cohesiveness, increased lubrication of both bread and potato bolus) and, consequently, facilitated faster bolus formation. While addition of mayonnaises to bread and potatoes decreased the number of chewing cycles before swallowing, consumers did not change muscle activities or jaw movements per chew. No effect of mayonnaise fat content on oral processing behavior of composite foods was observed. Low viscosity mayonnaise resulted in faster bolus formation and swallowing compared to high viscosity mayonnaise. Low viscosity mayonnaise penetrated faster into bread boli leading to faster softening of bread boli. Also in the case of potato, low viscosity mayonnaise lead to faster bolus formation than for high viscosity mayonnaise. The low viscosity mayonnaise mixed more easily with potato bolus pieces, enhancing adhesion between pieces. Both mayonnaise fat content and viscosity influenced sensory perception of composite foods considerably, especially in terms of fattiness and creaminess. We conclude that oral processing behavior, bolus formation and sensory perception of solid carrier foods can be modified considerably by condiments. While composition and rheological properties of condiments have a large effect on bolus formation and sensory perception of solid carrier foods, these aspects have a limited effect on oral processing behavior of composite foods. Oral processing behavior is dominated by the properties of the solid carrier food. Tailoring condiment-carrier combinations could be an effective strategy to increase healthy eating, alter food intake for populations such as the elderly, and increase food appreciation.

Masticatory properties in pre-modern Holocene populations from Northern China.

Recent studies indicate that evolution of the craniofacial skeleton is influenced by dietary behavior, which in turn alters masticatory efficacy and temporomandibular joint (TMJ) stability. In this study the mechanical properties of the masticatory system and the integrity of the TMJ in human populations from Northern China, dated to between 3800 BCE and 100 CE, were assessed. The results demonstrate that the mechanical efficiency is comparable to other modern human populations, though variations are present across different populations. While the ratio of overall weighted muscle efficiency for incisor loading vs. molar loading in pastoral and some recent agricultural groups is similar to early Homo sapiens, the ratio in more ancient agricultural groups is similar to the ratio in populations with heavy anterior paramasticatory activities, such as Neandertals, Inuits, and Native Americans. The TMJ vulnerability negatively correlates with the maxillary dental arch size, and positively with the condylar size. These findings suggest that there are multi-directional strategies in adaptation to heavy anterior teeth loading, such as increasing anterior teeth loading efficiency, increasing facial height, increasing facial breath and facial orthognathy, or decreasing anterior facial length. Furthermore, populations or individuals with a smaller dental arch and high biting efficiency could more easily injure the TMJ during unilateral loadings, which may explain the higher prevalence of TMJ disorders in modern humans, especially in women. These findings further reflect the impact of diachronic changes of the masticatory apparatus and lifestyle and their impact on oral health during recent human history.

Ring Shear Tester as an in-vitro testing tool to study oral processing of comminuted potato chips.

Oral processing of solid foods is an extremely dynamic and complicated activity that involves multiple processes in tandem such as comminution, mixing, dilution, hydration and enzymatic breakdown that gradually transform the food from a morsel or a bite to a bolus that is ready for swallowing. It is hypothesised that just after "first bite" and initial particle reduction and hydration of solid brittle foods, the response to deformation of food particles is analogous to studies on the flowability and cohesion of wetted powders, which are effectively characterised using a Ring Shear Tester (RST). We examine this hypothesis and determine whether the RST measures properties of solid snack foods (potato chips or crisps, PCs) that are relevant to their dynamic sensory response, which includes capturing the effect of hydration on comminuted PCs. The RST is found to differentiate PCs obtained from different manufacturing sources (e.g. baked versus fried), and its measurements of cohesion and friction can be considered in context of the structure and composition of the PCs as well as oral processing. Remarkably, RST measurements for this small set of PC samples correlate with several sensory attributes that arise during mastication, which includes Sharpness and Ease of Clearance. This study highlights the potential of the RST as a new tool for oral processing research.

Haloperidol-Induced Preclinical Tardive Dyskinesia Model in Rats.

Haloperidol is a first-generation antipsychotic used in the treatment of psychoses, especially schizophrenia. This drug acts by blocking dopamine D2 receptors, reducing psychotic symptoms. Notwithstanding its benefits, haloperidol also produces undesirable impacts, in particular extrapyramidal effects such as tardive dyskinesia (TD), which limit the use of this and related drugs. TD is characterized by repetitive involuntary movements occurring after chronic exposure therapy with haloperidol. Symptoms most commonly manifest in the orofacial area and include involuntary movements, tongue protrusion, pouting lips, chewing in the absence of any object to chew, and facial grimacing. The most serious aspect of TD is that it may persist for months or years after drug withdrawal and is irreversible in some patients. This unit, aimed at facilitating the study of TD, describes methods to induce TD in rats using haloperidol, as well as procedures for evaluating the animals's TD-related symptoms. © 2019 by John Wiley & Sons, Inc.

Brain activation patterns during unilateral premolar occlusion.

OBJECTIVE: To observe the characteristics of brain activation during unilateral premolar occlusion. METHODS: Functional magnetic resonance imaging was collected from 10 healthy volunteers during occlusion of the left first premolar (L1), left second premolar (L2), and right first premolar (R1). The brain activation patterns were analyzed, and the primary sensorimotor cortex, supplementary motor area, insula, thalamus, and prefrontal cortex were chosen as regions of interest. RESULTS: Single premolar occlusion activated the precentral gyrus, postcentral gyrus, cerebellum, thalamus, frontal lobe, hippocampus, cingulate gyrus, and parietal lobe. The brain areas showing activation during single premolar occlusion were similar to those activated by chewing. The activation pattern of L1 was more similar to that of L2 than R1. No significant left and right hemisphere differences in signal intensity were detected within the regions of interest. CONCLUSION: Brain activation patterns from two ipsilateral premolars were more similar than the pattern from a contralateral premolar.

Chemical effects of chewing sticks made of Salvadora persica.

OBJECTIVE: The chewing sticks are widely used in many regions of Asia and Africa as a traditional tool to maintain oral hygiene. Salvadora persica L. (S. persica), also known as Arak or Miswak, a member of the salvadoraceae family. Chewing sticks, made up from S. persica, have chemical antibacterial properties and mechanical effects. The study aimed to investigate possible chemical effects of S. persica on dental plaque, sub-gingival microbiota and gingival inflammation. In order to achieve this, we inactivated some sticks through boiling to be used as inactive, but mechanically comparable control sticks. METHODS: In a double-blinded crossover trial, 24 patients with mild-to-moderate periodontitis were randomly allocated to use either fresh activated Miswak or inactivated Miswak for 3-week period. Plaque index (PI), gingival index (GI), visual plaque index (VPI) and bleeding on probing (BOP) were evaluated before and immediately following the experimental period. Sub-gingival plaque samples were analysed using DNA-DNA hybridization technique. The study was repeated with the participants switching the type of Miswak they used after a 7-week of "washout" period. RESULTS: There were no significant differences in the microflora after using active and inactive Miswak. Sixteen species of bacteria showed an increase (P < 0.05) after the usage of inactive Miswak, as compared to pretreatment values. No species showed a similar change after the use of active Miswak. There were no significant differences between active and inactive Miswak regarding the registered clinical variables. CONCLUSION: This study has not shown any clinical effect of the chemically active Miswak, but there was a tendency towards an effect on the microflora.

Effects of electrostimulation associated with masticatory training in individuals with down syndrome. / Efeitos da eletroestimulação associada ao treino mastigatório em pessoas com síndrome de down.

Purpose Investigate and measure the effects of electrostimulation on the orofacial musculature and on the chewing, breathing and swallowing functions of individuals with Down syndrome. Methods Study participants were 16 individuals with Down syndrome (six males and 10 females) from an institutional extension project aged nine to 25 years. Speech-language pathology assessment was performed using the protocol of Orofacial Myofunctional Evaluation with Scores (OMES) pre- and post-intervention. This protocol comprised eight weekly electrostimulation sessions. Functional Electrical Stimulation (FES) current was used at a frequency of 10Hz in warm-up and 30Hz in application, intermittent stimulation (cycling pulses) with ON-time of 5s and OFF-time of 10s common to both stages, and pulse width of 200µs in warm-up and 250µs in application. Results Significant differences were observed between pre- and post-application of FES regarding cheek appearance (flaccidity and arching), tongue mobility (right and left laterality), and musculature behavior during performance of functions of the stomatognathic system: respiration, deglutition (lip behavior), and mastication (bite and trituration). Conclusion Effects of electrostimulation associated with masticatory training of the masseter muscles were statistically identified, with functional gains in chewing, breathing and swallowing performance in individuals with Down syndrome.

Complete dentures for a patient after a stroke by means of orofacial myofunctional therapy: A clinical report.

After a stroke, patients frequently show compromised swallowing, mastication, and speech, as well as unfavorable motion and deviation of the tongue and mandible. The dentist can improve the oral rehabilitation of a patient with deteriorated facial and oral muscles after a stroke by incorporating orofacial myofunctional therapy. This report describes a method for tongue exercises and correction of mandible deviation in an edentulous patient after a stroke by using a pearl on a wire in the anteriomedian palatal part of the maxillary denture.

Effects of orofacial myofunctional therapy on masticatory function in individuals submitted to orthognathic surgery: a randomized trial.

OBJECTIVES: The esthetic and functional results of orthognathic surgery of severe dentofacial deformities are predictable, however there are differences regarding the effects on stomatognathic system. The aim was to investigate the effects of orofacial myofunctional therapy (OMT) on the masticatory function in individuals with dentofacial deformity submitted to orthognathic surgery (OGS). MATERIAL AND METHODS: Forty-eight individuals (18-40 years) were evaluated, 14 undergoing OMT (treated group-TG), 10 without this treatment (untreated group-UTG) and 24 in a control group with normal occlusion; for clinical aspects the data of an individual was missed (n=46). Chewing was performed using the Expanded protocol of orofacial myofunctional evaluation with scores (OMES-E). Muscle tone and mobility were also analyzed before (P0), three (P1) and six months (P2) after OGS. Surface electromyography of the masseter and temporalis muscles was performed, considering the parameters amplitude and duration of act and cycle, and the number of masticatory cycles. The OMT consisted of ten therapeutic sessions along the postoperative period. The results were compared using parametric and non-parametric tests. RESULTS: TG showed higher scores in P1 and P2 than P0; for the masticatory type the scores in P2 were significantly higher than P0. In addition, the proportion of individuals with adequate tone of lower lip and adequate tongue mobility for TG increased significantly from P1 and P2 in relation to P0. The EMG results showed a decrease in act and cycle duration in P2 in relation to P0 and P1 for the TG; furthermore the values were close to controls. An increase in the number of cycles from P0 to P2 was also observed, indicating faster chewing, which may be attributed to an improvement of balanced occlusion associated with OMT. CONCLUSION: There were positive effects of OMT on the clinical and electromyography aspects of chewing in individual submitted to orthognathic surgery.

Effects of orofacial myofunctional therapy on masticatory function in individuals submitted to orthognathic surgery: a randomized trial

Abstract Objectives: The esthetic and functional results of orthognathic surgery of severe dentofacial deformities are predictable, however there are differences regarding the effects on stomatognathic system. The aim was to investigate the effects of orofacial myofunctional therapy (OMT) on the masticatory function in individuals with dentofacial deformity submitted to orthognathic surgery (OGS). Material and Methods: Forty-eight individuals (18-40 years) were evaluated, 14 undergoing OMT (treated group-TG), 10 without this treatment (untreated group-UTG) and 24 in a control group with normal occlusion; for clinical aspects the data of an individual was missed (n=46). Chewing was performed using the Expanded protocol of orofacial myofunctional evaluation with scores (OMES-E). Muscle tone and mobility were also analyzed before (P0), three (P1) and six months (P2) after OGS. Surface electromyography of the masseter and temporalis muscles was performed, considering the parameters amplitude and duration of act and cycle, and the number of masticatory cycles. The OMT consisted of ten therapeutic sessions along the postoperative period. The results were compared using parametric and non-parametric tests. Results: TG showed higher scores in P1 and P2 than P0; for the masticatory type the scores in P2 were significantly higher than P0. In addition, the proportion of individuals with adequate tone of lower lip and adequate tongue mobility for TG increased significantly from P1 and P2 in relation to P0. The EMG results showed a decrease in act and cycle duration in P2 in relation to P0 and P1 for the TG; furthermore the values were close to controls. An increase in the number of cycles from P0 to P2 was also observed, indicating faster chewing, which may be attributed to an improvement of balanced occlusion associated with OMT. Conclusion: There were positive effects of OMT on the clinical and electromyography aspects of chewing in individual submitted to orthognathic surgery.

Efeitos da eletroestimulação associada ao treino mastigatório em pessoas com síndrome de down / Effects of electrostimulation associated with masticatory training in individuals with down syndrome

RESUMO Objetivo Investigar e mensurar os efeitos da eletroestimulação na musculatura orofacial e nas funções de mastigação, respiração e deglutição dos indivíduos com síndrome de Down. Método Participaram da pesquisa 16 indivíduos com Síndrome de Down, sendo seis do gênero masculino e dez do gênero feminino com idade entre 9 e 25 anos, participantes de um projeto de extensão institucional. Foram realizadas avaliações fonoaudiológicas com uso do protocolo AMIOFE antes e após a intervenção, que consistiu em oito sessões de eletroestimulação semanais. A corrente utilizada foi a Functional Electrical Estimulation (FES), com uma frequência de 10Hz no aquecimento e 30 Hz na aplicação, em um tempo ON de 5s e OFF de 10s comuns nas duas etapas, e com a largura de pulso de 200(µs) no aquecimento e 250(µs) na aplicação. Resultados Observaram-se diferenças significativas após aplicação da eletroestimulação (FES) em relação ao aspecto das bochechas quando comparadas flacidez/arqueamento pré e pós o estímulo elétrico, diferenças na mobilidade de língua (lateralidade direita e esquerda), no comportamento da musculatura na execução das funções estomatognáticas de respiração, melhoria no comportamento dos lábios durante a deglutição e mudanças expressivas no processo de mastigação (mordida e trituração). Conclusão Foi identificado estatisticamente que houve efeito após a eletroestimulação associada ao treino mastigatório nos músculos masseteres, com ganhos funcionais na execução da mastigação, respiração e deglutição, em pessoas com Síndrome de Down.

ABSTRACT Purpose Investigate and measure the effects of electrostimulation on the orofacial musculature and on the chewing, breathing and swallowing functions of individuals with Down syndrome. Methods Study participants were 16 individuals with Down syndrome (six males and 10 females) from an institutional extension project aged nine to 25 years. Speech-language pathology assessment was performed using the protocol of Orofacial Myofunctional Evaluation with Scores (OMES) pre- and post-intervention. This protocol comprised eight weekly electrostimulation sessions. Functional Electrical Stimulation (FES) current was used at a frequency of 10Hz in warm-up and 30Hz in application, intermittent stimulation (cycling pulses) with ON-time of 5s and OFF-time of 10s common to both stages, and pulse width of 200μs in warm-up and 250μs in application. Results Significant differences were observed between pre- and post-application of FES regarding cheek appearance (flaccidity and arching), tongue mobility (right and left laterality), and musculature behavior during performance of functions of the stomatognathic system: respiration, deglutition (lip behavior), and mastication (bite and trituration). Conclusion Effects of electrostimulation associated with masticatory training of the masseter muscles were statistically identified, with functional gains in chewing, breathing and swallowing performance in individuals with Down syndrome.

Interferential effect of the over-erupted third molar on chewing movement.

OBJECTIVE: To clarify whether over-eruption of the mandibular third molar can disturb chewing movement. METHODS: Eighteen patients with a unilateral mandibular over-erupted third molar confirmed by both study cast observation and T-scan occlusal detection were selected from a sample of patients with complaints of temporomandibular disorder (TMD) symptoms. A unilateral gum-chewing trace was recorded separately for left and right side chewing by an electrognathography system. The average chewing pattern (ACP) was created based on segments from the recorded chewing trace to represent the chewing movement characteristics of each individual. Two factors, the TMD symptomatic side and the over-eruption side, were analysed for their effects on values of difference in the parameters (Δvalue) regarding the ACP between chewing with right and left side. Three-dimensional amplitudes of ACP and the cross point value of ACP with the vertical axis (termed the cross zero point value) which described the turning point of the chewing cycle from the balancing side to the working side, were compared between sides. RESULTS: The over-eruption side had an effect on the Δvalue of the medial amplitude, the lateral amplitude, and the cross zero point (P<0.05), but the symptomatic side didn't (P>0.05). When chewing on the over-eruption side, the medial amplitude was shorter, the lateral amplitude was larger, and the cross zero point value was smaller than those when chewing on the other side (P<0.05). CONCLUSION: The present data indicate an effect of the over-erupted mandibular third molar on the chewing pattern while that from the symptom(s) is limited.

Perturbed oral motor control due to anesthesia during intraoral manipulation of food.

Sensory information from periodontal mechanoreceptors (PMRs) surrounding the roots of natural teeth is important for optimizing the positioning of food and adjustment of force vectors during precision biting. The present experiment was designed to test the hypothesis; that reduction of afferent inputs from the PMRs, by anesthesia, perturbs the oral fine motor control and related jaw movements during intraoral manipulation of morsels of food. Thirty healthy volunteers with a natural dentition were equally divided into experimental and control groups. The participants in both groups were asked to manipulate and split a spherical candy into two equal halves with the front teeth. An intervention was made by anesthetizing the upper and lower incisors of the experimental group while the control group performed the task without intervention. Performance of the split was evaluated and the jaw movement recorded. The experimental group demonstrated a significant decrease in measures of performance following local anesthesia. However, there was no significant changes in the duration or position of the jaw during movements in the experimental and control group. In conclusion, transient deprivation of sensory information from PMRs perturbs oral fine motor control during intraoral manipulation of food, however, no significant alterations in duration or positions of the jaw during movements can be observed.

Fine motor control of the jaw following alteration of orofacial afferent inputs.

OBJECTIVE: The study was designed to investigate if alteration of different orofacial afferent inputs would have different effects on oral fine motor control and to test the hypothesis that reduced afferent inputs will increase the variability of bite force values and jaw muscle activity, and repeated training with splitting of food morsel in conditions with reduced afferent inputs would decrease the variability and lead to optimization of bite force values and jaw muscle activity. MATERIAL METHODS: Forty-five healthy volunteers participated in a single experimental session and were equally divided into incisal, mucosal, and block anesthesia groups. The participants performed six series (with ten trials) of a standardized hold and split task after the intervention with local anesthesia was made in the respective groups. The hold and split forces along with the corresponding jaw muscle activity were recorded and compared to a reference group. RESULTS: The hold force and the electromyographic (EMG) activity of the masseter muscles during the hold phase were significantly higher in the incisal and block anesthesia group, as compared to the reference group (P < 0.001). However, there was no significant effect of groups on the split force (P = 0.975) but a significant decrease in the EMG activity of right masseter in mucosal anesthesia group as compared to the reference group (P = 0.006). The results also revealed that there was no significant effect of local anesthesia on the variability of the hold and split force (P < 0.677). However, there was a significant decrease in the variability of EMG activity of the jaw closing muscles in the block anesthesia group as compared to the reference group (P < 0.041), during the hold phase and a significant increase in the variability of EMG activity of right masseter in the mucosal anesthesia group (P = 0.021) along with a significant increase in the EMG activity of anterior temporalis muscle in the incisal anesthesia group, compared to the reference group (P = 0.018), during the split phase. CONCLUSIONS: The results of the present study indicated that altering different orofacial afferent inputs may have different effects on some aspects of oral fine motor control. Further, inhibition of afferent inputs from the orofacial or periodontal mechanoreceptors did not increase the variability of bite force values and jaw muscle activity; indicating that the relative precision of the oral fine motor task was not compromised inspite of the anesthesia. The results also suggest the propensity of optimization of bite force values and jaw muscle activity due to repeated splitting of the food morsels, inspite of alteration of sensory inputs. CLINICAL RELEVANCE: Skill acquisition following a change in oral sensory environment is crucial for understanding how humans learn and re-learn oral motor behaviors and the kind of adaptation that takes place after successful oral rehabilitation procedures.

Effect of a new treatment protocol called Functional Chewing Training on chewing function in children with cerebral palsy: a double-blind randomised controlled trial.

Cerebral palsy (CP) is a group of permanent sensorimotor impairments. Children with CP have various feeding difficulties including chewing disorder, which may affect their nutritional status. Functional Chewing Training (FuCT) was designed as a holistic approach to improve chewing function by providing postural alignment, sensory and motor training, and food and environmental adjustments. This study aimed to investigate the effect of FuCT on chewing function in children with CP. This study was designed as a double-blind, randomised controlled trial. Eighty CP children with chewing disorder were randomised and split between the FuCT group (31 males, 19 females; mean age 3·5 ± 1·9 years) and the control group (16 males, 14 females; 3·4 ± 2·3 years) receiving traditional oral motor exercises. Each group received the training programme for 12 weeks with weekly follow-up and with two evaluations at baseline and end of 12 weeks. Chewing function was evaluated by analysing video recordings and scored with the Karaduman Chewing Performance Scale (KCPS). The Behavioral Pediatrics Feeding Assessment Scale (BPFAS) was used to evaluate feeding behaviours of children. A significant improvement was observed in KCPS scores at 12 weeks after training in the FuCT group (P < 0·001), but no change was found in the control group (P = 0·07). A significant improvement was detected in all parameters of BPFAS at 12 weeks after training in the FuCT group (P < 0·001) and in four parameters of BPFAS in the control group (P = 0·02, P = 0·02). FuCT is an effective method to improve chewing function compared with traditional oral motor exercises.