Artificial Test Food Research Articles

The effect of bolus size on masticatory parameters at swallowing threshold in children using a hard, solid, artificial test food.

The effect of different bolus sizes on food breakdown has been studied in adults, but not in children. The objective of this study was to study median particle size (MPS) and other parameters of masticatory function at swallowing threshold (ST) in 8–10‐year‐old‐children with two different bolus sizes. A randomized crossover trial was undertaken in 89 eight to ten‐year‐old children. The study was performed with informed consent and ethical approval. The artificial test food used was made of a condensation silicone (Optosil Comfort) following a standardized protocol. Two bolus sizes (three or four quarters of a 20‐mm diameter, 5‐mm thick tablet) were randomized to avoid an order effect and tested in different sessions. Variables were: MPS (X 50) at ST, number of cycles until ST, sequence and cycle duration as well as cycles/g. Comparisons were performed with paired t and Wilcoxon tests, regressions and correlations were run. Cutoff for statistical significance was .05. Statistically significant differences were found for all variables; X 50 (2.5 ± 0.8 vs. 2.8 ± 0.7 mm, p < .001), cycles until ST (38 vs. 40, p = .022), sequence (25 vs. 27 s, p = .003), and cycle duration (650 vs. 683 ms, p = .015) and cycles/g (27 vs. 21 cycles/g, p < .001), three or four quarters, respectively. In conclusion, in children, as in adults, chewing on a bigger bolus size leads to a larger MPS (X 50) at ST. When chewing on a larger bolus the number of cycles increases, but not enough to swallow the same particle size since the number of cycles/g is less with a bigger bolus size.

Masticatory function in children with Down syndrome

The objective was to study masticatory function of 8 to 10-year-old children with Down syndrome (DS) through the evaluation of maximum occlusal force and masticatory performance (via medium particle size) and compare it to that of children of the same age without DS. Methods: A convenience sample of eight, 8–10-year-old children with DS were included in this cross-sectional study. The study had ethical approval and parents provided informed consent. Exclusion criteria were large carious lesions, dental pain or previous orthodontic/orthopedic treatment. Masticatory performance was evaluated with an artificial test food (Optosil Comfort®) after 20 cycles and at swallowing threshold. The chewed material was collected, dried and sieved. The material on each sieve was weighed; the weights were used to calculate medium particle size. Maximum occlusal force (1st permanent molars) was determined using the GM10 Nagano Keiki Co.™ portable transducer. The number of cycles until swallowing threshold, cycle and sequence durations were also compared. The data for the reference group (n = 32) came from a previous study in children of the same age. Descriptive statistics as well as comparisons with Mann-Whitney tests and simple and multiple regression analysis were performed. Cutoff was set at p≤.05. Results: Medium particle size is larger by 44% after 20 chewing cycles and 75% at swallowing threshold (p<.05) in children with DS. Median maximum occlusal force was 254 kN in DS children and 499 kN in children without the syndrome (p<.001). 48% of the variance in maximum occlusal force is explained by having DS. There were also significant differences in sequence and cycle durations. All significant differences had large effect sizes (˃1). Although the children with DS chewed more cycles before swallowing threshold the difference was not significant. Conclusions: Children with DS have approximately 50% of the masticatory performance and maximum occlusal force of children of the same age without DS. These findings can be associated to the feeding problems reported in children with DS.

Impact of the Occlusal Morphology of Artificial Teeth on Bimaxillary Denture Treatment in Elderly Individuals: A Clinical Trial

To evaluate the performance of complete dentures (CD) with anatomical and nonanatomical teeth in completely edentulous elderly individuals regarding oral health-related quality of life (OHRQoL), satisfaction, masticatory performance (MP), need for adjustment after CD placement, and patient preference for occlusal type. A randomized crossover clinical trial comprising 50 edentulous elderly individuals was conducted. The participants were divided into two groups: AT-NT (rehabilitated initially with anatomical teeth and 3 months later with nonanatomical teeth) and NT-AT (rehabilitated initially with nonanatomical teeth and 3 months later with anatomical teeth). OHRQoL was analyzed using the OHIP-EDENT; a satisfaction questionnaire was applied; MP was evaluated by the median particle size (×50) after chewing an artificial test food; and the number of adjustments of the prosthesis base was assessed quantitatively. Overall, 34 elderly individuals (mean age: 69 years) were analyzed. No significant difference was observed between CD users with anatomical and nonanatomical teeth for OHRQoL (P = .674), satisfaction (P = .725), MP (P = .849), or number of adjustments (P = .135). Most subjects (52.9%) did not express a preference for any occlusal surface type. However, among those with a preference, the majority (32.4%) opted for nonanatomical teeth. Both posterior tooth types are eligible for oral rehabilitation in elderly users of conventional CDs, as the variables were not influenced by occlusal morphology. However, further studies are warranted in highly resorbed mandibular edges or in cases of adaptation difficulties, as the results may differ.

Optimizing a determination of chewing efficiency using a solid test food.

A test using a solid food is relevant to measure chewing ability (CA) as (a) it includes an integrated functioning of all oral structures involved, (b) an impairment of chewing a solid food causes inevitably diet restrictions, and (c) chewing efficiency (CE) can easily be defined. CE is the number of chewing cycles, N(1/2-Xo), needed to attain a particular chewing outcome (a median particle size, X 50 , which is half the initial particle size Xo) whereas chewing performance (CP) is a state of chewing outcome (X 50 ) at an arbitrary number of chewing cycles. The use of CE is preferable for CA because inter-subject ratios are constant regardless of the initial conditions of the test food. Furthermore, the inter-subject variation is two times larger for CE values than for CP ones, yielding a better inter-subject differentiation of CA. However, a determination of CP needs only one N-value, and that of CE at least two N-values for enabling an interpolation of N(1/2-Xo). Using samples of only two half-cubes (9.6 x 9.6 x 4.8 mm; limiting test load) of Optosil (an artificial test food), and detailed previous information on log(X 50 )-log(N) relationships (Liu et al., Archives of Oral Biology, 2018, 91, 63-77) as a "gold standard," a short procedure has been developed for a priori choosing two appropriate N-numbers, and the subsequent determination of a subject's CE. This procedure has been developed using results from 20 young adults (23.7 years, SD 1.1) and was validated in 10 middle-aged and older adults (52.3 years, SD 10.1), where impairments in the dentition were reflected in the CE-values. Our short procedure to determine CE will improve studies on relationships between CA and food preference, or between CA and dental factors and/or physiological factors. The first type of relationship may be of interest for food industry whereas the second type may be of interest for population studies in rapidly aging societies and for clinical studies in dentistry. Results can be compared between subjects and studies without bias by using CE rather than CP as a measure of CA.

Relationship Between Masticatory Function Impairment and Oral Health-Related Quality of Life of Edentulous Patients: An Interventional Study.

To investigate the influence of impaired masticatory function on the oral health-related quality of life of conventional complete denture wearers before and after the transition to implant-retained mandibular overdentures. Masticatory function and oral health-related quality of life were evaluated in 40 edentulous patients after 3 months of adaptation to complete dentures and after transition to implant-retained mandibular overdentures. Masticatory function was evaluated through the swallowing threshold test with a standardized portion of an artificial test food (Optocal) to determine median particle size (×50) and homogenization index (B). After the test, the masticatory function outcomes were used to categorize patients in 2 groups according to chewing performance: (i) satisfactory or (ii) unsatisfactory. The cutoff value for ×50 was based on a preestablished value of 3.68mm, whereas for the B index, median values were adopted for categorization. The oral health-related quality of life was analyzed via the Oral Health Impact Profile for Edentulous Adults (OHIP-EDENT) questionnaire. The Mann-Whitney test was used to compare masticatory function outcomes and OHIP-EDENT scores, and associations were checked using the Spearman correlation test and multiple linear regression. Masticatory function was significantly correlated with functional limitation (p = 0.02) and physical disability (p = 0.04) for complete denture wearers with unsatisfactory masticatory function. After the transition to implant-retained mandibular overdentures, only the psychological discomfort domain (p = 0.02) was influenced by the masticatory function category. Multiple linear regression analysis revealed that only the functional limitation domain (p < 0.001) of the complete denture wearers was associated with masticatory function outcomes. Implant-retained mandibular overdentures eliminate the problems that lead to functional limitations, consequently improving masticatory function and oral health-related quality of life of these individuals; however, patients with unsatisfactory masticatory function after transition to implant-retained mandibular overdentures still experience more psychological discomfort.

Influence of facial patterns on the masticatory function and quality of life of completely edentulous patients during the transition to implant-retained mandibular overdentures

Statement of problemAlthough implant-retained mandibular overdentures (IMOs) provide functional benefits, the influence of the vertical facial pattern (FP) and the anteroposterior skeletal discrepancy (ASD) on the masticatory function and patient-centered outcomes during the transition to IMOs is still uncertain. PurposeThe purpose of this interventional clinical study was to evaluate the influence of the FP and ASD on the masticatory function, oral health–related quality of life (OHRQoL), and satisfaction of completely edentulous patients before and after transition to IMOs. Material and methodsCephalometric analysis was performed on 42 participants before treatment. Ricketts analysis was used to classify the FP, and the maxillomandibular relationship to the base of the skull determined the ASD. Masticatory performance (MP) and swallowing threshold (ST) test results were evaluated by the multiple sieve method by using artificial test food (Optocal cubes) to determine the median particle size (×50), homogenization index (B), and masticatory efficiency based on sieves 5.6 (ME: 5.6) and 2.8 (ME: 2.8). OHRQoL and satisfaction were evaluated by using the Dental Impact on Daily Living questionnaire. The data were analyzed using mixed-effects linear regression models to estimate the effect of time, FP, ASD, age, and sex on MP, ST, and OHRQoL. ResultsThe MP, ST, OHRQoL, and satisfaction improved significantly after IMO loading, irrespective of FP and ASD. However, MP outcomes were most negatively affected mainly among dolichofacial (B and ME: 2.8), class II, and class III (×50, B, and ME: 2.8) participants. The ST test showed that class II participants still showed inferior ×50 values and performed a lower number of cycles than class I and class III participants. Women presented reduced masticatory function for all MP and ST outcomes and reported lower coefficients for appearance and general performance domains than men. ConclusionsThe MP test detected more subtle improvements than the ST test, especially in class III participants. The class II participants benefited the least from the IMO installation according to the ST test. The IMO treatment improved the OHRQoL and satisfaction of edentulous patients, irrespective of the FP or ASD.

Electromyographic activity of superficial masseter and anterior temporal muscles during unilateral mastication of artificial test foods with different textures in healthy subjects.

This study aimed to examine the electromyographic activity of superficial masseter and anterior temporal muscles during chewing gum and gummy jelly mastication in healthy subjects to reveal the difference of neuromuscular control of jaw-closing muscles, according to the food texture. Electromyographic activity was recorded in 30 adults with Angle Class I occlusion and unimpaired function from the bilateral superficial masseter and anterior temporal muscles during unilateral mastication of two test foods: standardized gummy jelly and color-changeable chewing gum. Differences in normalized electromyographic activity and asymmetry index values between gummy jelly and chewing gum mastication were analyzed during the early, middle, and late phases of mandibular closure. Furthermore, changes among the three closing phases were compared for each test food. High electromyographic activity of both muscles tended to occur bilaterally during the middle and late closing phases during gummy jelly mastication, but increased muscle activity in the late closing phase was not observed during chewing gum mastication. The asymmetry index of the superficial masseter muscle increased significantly from early to late closure, regardless of the food texture, but it tended to decrease for the anterior temporal muscle during gummy jelly mastication. The different aspects of the chewing process between the comminution and mixing test measures are necessary to elicit the different human neuromuscular strategies of chewing for different test foods. These characteristic EMG activities of the superficial masseter and anterior temporalis muscles may be used as supporting diagnostic information during patient assessments and a reference during evaluation of masticatory system disharmony or dysfunction.

Psychometric Analysis and Masticatory Efficiency of Elderly People with Single-Implant Overdentures.

The aim of this paired clinical study was to evaluate psychometric parameters (patient satisfaction and masticatory ability) and masticatory efficiency in elderly people before and after oral rehabilitation by a single-implant overdenture. This study included elderly individuals with residual alveolar bone height classified as Class III or IV according to the American College of Prosthodontics, and who wore clinically unsatisfactory complete dentures. Subjects first received new maxillary and mandibular conventional complete dentures. After 2 months of patient adaptation to the new complete dentures, subjective and objective variables were measured. Satisfaction with the new complete dentures was verified by applying a visual analog scale to rate patient satisfaction with stability, comfort, ability to chew, ability to speak, ease of cleaning, esthetics, and general satisfaction of their new complete dentures. Masticatory ability was assessed by asking participants to rate on a visual analog scale their ability to chew foods with different roughness and consistencies. Masticatory efficiency was measured by the sieving method using a silicone-based artificial test food. After evaluations were completed, each participant received one implant, which was placed in the symphysis region. After 3 months of implant osseointegration, the conventional complete dentures were transitioned to mandibular single-implant overdentures through placement of a low-profile attachment on the intaglio surface of the prostheses. Subjects used the single-implant overdentures for 2 months, and then all variables were reevaluated. Parametric t test and nonparametric Wilcoxon statistical tests were used to analyze data. Participants reported increased satisfaction with stability of their mandibular single-implant overdentures compared with their new conventional complete dentures. However, satisfaction with the esthetics decreased when the new complete denture was converted into the single-implant overdenture (P < .05). Masticatory ability with the rehabilitation was not different between the new conventional complete dentures and the single-implant overdentures; however, transition to the single-implant overdenture greatly increased masticatory efficiency (P < .0001). Single-implant overdentures changed the patient perceptions, improving their satisfaction with stability, although decreasing satisfaction with esthetics. Despite that, masticatory efficiency of elderly individuals with decreased residual bone height was greatly improved after single-implant overdenture use.

Immediate effects of temporary bite-raising with light-cured orthodontic band cement on the electromyographic response of masticatory muscles.

Objective:To assess the immediate effects of temporary bite-raising using light-cured orthodontic band cement on the superficial masseter and anterior temporalis electromyography (EMG) activity in healthy adults.Materials and Methods:Surface EMG signals were recorded bilaterally from the superficial masseter and anterior temporalis muscles of 30 volunteers with a normal occlusion, before and after having temporary bite-raising. The bite-raising was done by adding light-cured orthodontic band cement (3x5x2 mm WxLxH) on the lingual cusps of both upper first molars. The measurements were recorded (i) at rest, (ii) while clenching in centric occluding position and (iii) while chewing on an artificial test food. The EMG activity at rest and during clenching, the maximum voltage, and the duration of the identified EMG signal burst while chewing the artificial test food before and after temporary bite-raising were statistically compared using the paired t-test or the Wilcoxon signed-rank test based on the normality of the variables. The significance level was set at 5%.Results:After temporary bite-raising, we found no significant change in integral EMG activity at rest position for the superficial masseter (mean difference (MD)=7.5 μVs) and for the anterior temporalis muscle (MD=36.8 μVs); however, the integral EMG activity during clenching was significantly reduced for the superficial masseter (MD=201.2 μVs) and for the anterior temporalis muscle (MD=151.8 μVs). During mastication, the maximum voltage of the identified burst was significantly reduced on the preferred chewing side of the superficial masseter and anterior temporalis muscles (MD=127.9 and 47.7 μV, respectively), while no significant change was found for the duration of the identified burst (MD=-34.1 and 3.4 ms, respectively) after temporary bite-raising.Conclusion:The results point to an altered neuromuscular behavior during clenching and chewing immediately after temporary bite-raising with light-cured orthodontic band cement. This information is relevant for orthodontists to inform their patients what will happen to their masticatory muscle activity when this bite-raising method is used.

Determining chewing efficiency using a solid test food and considering all phases of mastication

ObjectivesFollowing chewing a solid food, the median particle size, X50, is determined after N chewing cycles, by curve-fitting of the particle size distribution. Reduction of X50 with N is traditionally followed from N ≥ 15–20 cycles when using the artificial test food Optosil®, because of initially unreliable values of X50. The aims of the study were (i) to enable testing at small N-values by using initial particles of appropriate size, shape and amount, and (ii) to compare measures of chewing ability, i.e. chewing efficiency (N needed to halve the initial particle size, N(1/2-Xo)) and chewing performance (X50 at a particular N-value, X50,N). Design8 subjects with a natural dentition chewed 4 types of samples of Optosil particles: (1) 8 cubes of 8 mm, border size relative to bin size (traditional test), (2) 9 half-cubes of 9.6 mm, mid-size; similar sample volume, (3) 4 half-cubes of 9.6 mm, and 2 half-cubes of 9.6 mm; reduced particle number and sample volume. All samples were tested with 4 N-values. Curve-fitting with a 2nd order polynomial function yielded log(X50)-log(N) relationships, after which N(1/2-Xo) and X50,N were obtained. ConclusionsReliable X50-values are obtained for all N-values when using half-cubes with a mid-size relative to bin sizes. By using 2 or 4 half-cubes, determination of N(1/2-Xo) or X50,N needs less chewing cycles than traditionally. Chewing efficiency is preferable over chewing performance because of a comparison of inter-subject chewing ability at the same stage of food comminution and constant intra-subject and inter-subject ratios between and within samples respectively.

Adaptation to new complete dentures-is the neuromuscular system outcome-oriented or effort-oriented?

The aim of this study was to observe the adaptation strategy of the stomatognathic system during the adaptation of complete dentures, comprising masticatory parameters and subjective measures. Our hypothesis was that with new dentures, masticatory performance would increase while the effort of the system is kept constant. Thirty-two patients received standardized new complete dentures. Masticatory performance tests were conducted with old dentures (T1), immediately after incorporation of new dentures (T2) and after an adaptation period of 3months (T3). Patients habitually chewed the silicone-based artificial test food Optocal. The comminuted test food was analyzed and mean particle sizes (x50) were calculated. Simultaneously, surface EMGs of the anterior temporalis and masseter muscles were recorded. Specific (SMW) and total muscle work (TMW) were determined. Patients filled in the OHIP-49 questionnaire. Test conditions were compared using repeated-measures ANOVA with SPSS 22 (SPSS Inc.) RESULTS: Masticatory performance increased (P = 0.016) between old (x50 = 4.99 ± 0.28) and adapted new dentures (x50 = 4.80 ± 0.33). TMW deteriorated (P = 0.004) at T2 (from TMW1 = 119.77 ± 56.49 to TMW2 = 92.12 46.27), and increased again (P = 0.028) at T3 (TMW3 = 107.66 ± 44.65). OHIP scores decreased significantly in all subscales (P < 0.001…P = 0.046); the total score was reduced (P < 0.001) from 56.24 ± 29.05 (T1) to 34.66 ± 24.74 (T3). In complete denture wearers, masticatory performance improves over an adaptation period. Muscle work initially decreased before reaching its original level again after adaptation. Subjective parameters overestimated the functional improvements. The subjective evaluation does not adequately reflect functional improvements. The assessment of function requires an adaptation period.

Masticatory performance parameters for young adults with “normal” occlusion

Objective To develop reference data for young men/women on the variability of parameters used for the evaluation of masticatory function with an artificial test food. Methods Subjects included were 200 18–25-year olds with complete dentition and “normal” occlusion. An artificial test food was chewed in two tests (20 cycles and swallowing threshold), during which sequences/cycles were counted and timed. Medium-particle-size (MPS) and broadness of particle distribution were calculated evaluating the chewed material. Reference data was based on order statistics. Sex-specific 95% reference limits with 90% confidence intervals were calculated with RefVal-v2.1-software. Coefficients of variation were also obtained. Results Tables with reference data for young men/women chewing an artificial test food were constructed with the data collected displaying ample variability: MPS after 20 cycles anywhere between 0.7–3.5 mm or 14–84 cycles to deem the test food ready to be swallowed (C.V. 43% males/34% females). Conclusion There is much variability in masticatory parameters for young adults with good oral health.

Electromyographic activity of superficial masseter and anterior temporal muscles during unilateral mastication of artificial test foods with different textures in normal subjects

Electromyographic activity of superficial masseter and anterior temporal muscles during unilateral mastication of artificial test foods with different textures in normal subjects

How fast can treatment with overdentures improve the masticatory function and OHRQoL of atrophic edentulous patients? A 1-year longitudinal clinical study.

The aim of this prospective clinical study was to evaluate the masticatory function (MF) and subjective perception of patients with poor denture-bearing tissue in relation to change and the time required to identify an improvement in these parameters after rehabilitation with mandibular overdentures (MO) by two narrow-diameter two-piece implants. Twenty-three edentulous patients were selected for MO installation. The masticatory function (MF) was evaluated with the masticatory performance (MP) and swallowing threshold (ST) tests. In the MP test, each volunteer was instructed to masticate a portion of Optocal (standardized artificial test food) for 40 masticatory cycles. During the swallowing threshold test, the patients were instructed to chew a new portion of Optocal cubes until they felt the desire to swallow. The MF tests were performed while complete denture (CD) wearers (baseline) and 1, 3, 6, and 12months after MO loading. In addition, the subjective perception was assessed through the questionnaires Dental Impact on Daily Living (DIDL), Geriatric Oral Health Assessment Index (GOHAI), and Oral Health Impact Profile in Edentulous (OHIP- EDENT) at the baseline and 3, 6, and 12months after MO loading. A significant improvement in masticatory function (p<.05) was observed already in the first month of loading. Three months after MO loading, a significant improvement (p<.05) was found in the subjective perception of patients. The effect size indicates that the MO had the greatest impact on the domains related to function and comfort of all questionnaires and in relation to psychosocial domain of the GOHAI. The level of patient satisfaction increased significantly after the MO loading and reached >90% satisfied patients at 12months. The MO improved both the MF of the patient and their oral health-related quality of life and satisfaction regarding the prosthesis in a short time period.

Functional adaptation of the masticatory system to implant-supported mandibular overdentures.

The purpose of this study was to investigate the adaptation behavior of the stomatognathic system after immediate loading (24 to 72h after surgery) of two implants supporting mandibular overdentures, assessed on insertion and three months later. The study hypothesis was that insertion of the overdentures would significantly change masticatory performance and muscle activity at both times. Thirty subjects (nine female, mean age 69.64±11.81years; 21 male, mean age 68.67±7.41years) who participated in a randomized clinical trial were included in the study. Each patient was examined three times: (i) at baseline, after already having worn new dentures for three months (T1); (ii) immediately after insertion of the overdentures on the implants (T2); and (iii) after an adaptation period of three months (T3). Examination comprised assessment of masticatory performance with artificial test food (Optocal), and simultaneous bilateral surface EMG recording of the masseter and anterior temporalis muscles. Particle-size distribution (representative value X50 ), maximum muscle contraction (MVC), and total muscle work (TMW; area under the curve) were compared by use of repeated-measures analysis of variance (ANOVA). At T3, all measured variables (i.e., masticatory performance and muscle activity) were significantly different from those at T1. At T2, no significant changes were observed. The study hypothesis had to be rejected for T2 but accepted for T3. Functional rehabilitation (in terms of masticatory performance and masticatory muscle activity) does not occur immediately after immediate loading of two implants with mandibular overdentures, but requires a significant time for functional improvement.

The effects of temporo mandibular joint disorder with clicking symptom on children mastication performance in Deutero Malay race children aged 12-15 years

Temporo Mandibular Joint Disorder (TMD) could be caused by forward head posture. Articular sound/TMJ clicking is the most often sign and symptom for TMD that could happen in human being. The presence of TMD such as TMJ clicking would cause an imbalance masticatory system. The purpose of this research is to investigate TMJ clicking effects to masticatory performance. This research was cross-sectional study with a type of epidemiology survey. Subject were children aged 12-15 years old Deutero-Malay sub-races Live in Bandung and was taken using multi-stage random sampling technique. Subject; consisted of 24 children as control group and 28 children as TMJ clicking group. Both group were then checked for masticatory performance using multiple sieve method and 20x chewing of artificial test food. Mastication performance value represented by median particle size (MPS) particle distribution (b) for each group. MPS from TMJ clicking group (3.0571,SD=0.9990) showed higher value than control group (2.28958,SD=0.66838). Statistic analysis with t-test showed that there’s a significant result in both of group (pvalue=0,0024, α = 0,05). Conclussion, temporo mandibular joint clicking subject has lower masticatory performance.

Effect of short one-third lower face toward mastication performance in Deutero Malay

The one-third lower face height belongs to ideal proportion, ratio 1:1:1, of vertical face height. The one-third lower face height could be influenced by mastication. The one-third lower face height that shorter than normal ratio is generally followed by deep bite which may lead to temporomandibular disfunction even so eustachian tube disfunction, this condition may interfere mastication function, which can be measured by mastication performance. The research objective was to determine the effects of short lower face height to the mastication performance based on overbite. The research method was a cross-sectional study with epidemiology survey type. Research subjects 12-15 years old junior high school with Deutero Melayu Sub races in Bandung. Sampling technique used multistage random sampling by determining the size of the sample based on potluck sample and gained 24 children (group 1) with the normal ratio of vertical face height and 27 children with short lower facial height which were 11 children overbite normal (group 2) and 16 children deep bite (group 3). Mastication performance by 20 times chewing artificial test food then followed by sieving test. Mastication performance value represented by the median particle size (MPS) and the distribution of the particle distribution (b). The results of average MPS and b between group 1, 2 and 3 used statistical analysis MPS with ANOVA test which Fhit=5.56 and pvalue=0.0075, b which Fhit=3.41 and pvalue=0.0430 showed significant differences. Continued with group T test MPS (value = 0.0925) dan b (value = 0.2076) between group 1 and 2 showed a non significant differences. While between group 1 and 3 showed a highly significant differences in MPS (value = 0.0037 and  = 0,01) and a significant differences in b (value = 0.0141 and  = 0,05). Conclusions of this study were children with short lower face height and normal overbite did not decrease the mastication performance while children with deep bite decrease the mastication performance.

Pain, masticatory performance and swallowing threshold in orthodontic patients

The aim of this study was to assess pain, masticatory performance and swallowing threshold of patients undergoing orthodontic treatment. Ten patients of both genders (mean age of 17.25 ± 5.21 years), with complete permanent dentition, who underwent orthodontic treatment with fixed appliances were evaluated. The masticatory performance and the swallowing threshold were assessed by patient's individual capacity of fragmenting an artificial test food (Optocal) which was chewed and had the resulting particles processed by a standardized sieving method, presenting the median particle size (MPS) of crushed units. The intensity of pain / discomfort during chewing was evaluated by means of a visual analog scale. All tests were performed at the following times: T0 - before activating the orthodontic appliance; T1 - 24 hours after activation, and T2 - 30 days after activation. The results showed a significant increase in pain at T1 (T0 = 0.60 ± 0.70 mm; T1 = 66.2 ± 34.5 mm), returning to baseline values at T2 (3.20 ± 3.82 mm). Masticatory performance was also reduced in T1 (MPS = 10.15 ± 1.1 mm2) in comparison to T0 (MPS 7.01 ± 2.9 mm2) and T2 (MPS 6.76 ± 1.3 mm2). However, particle size was not affected in the swallowing threshold test (T0 = 5.47 ± 2.37 mm2; T1 = 6.19 ± 2.05 mm2; T2 = 5.94 ± 2.36 mm2). The orthodontic appliances did not interfere in the size of the particles that would be swallowed, even in the presence of pain.

The relationship between oral conditions, masticatory performance and oral health-related quality of life in children

ObjectiveTo evaluate the association between oral conditions, masticatory performance (MP) and oral health-related quality of life (OHRQoL) in 8–12 year-old children. Design150 Brazilian scholars were examined for caries and malocclusions. MP was evaluated based on the ability to comminute an artificial test food followed by the determination of the median particle size (X50) and particle distribution in different-sized sieves (“b”). OHRQoL was measured using the Brazilian versions 8–10 and 11–14 of the child perceptions questionnaire (CPQ), considering the following domains: oral symptoms (OS), functional limitations (FL), emotional well-being (EW) and social well-being (SW). Higher scores indicated worse OHRQoL. Data were submitted to Spearman's correlation test and multiple linear regression analysis. ResultsThere were significant positive correlations between the psychosocial and OS domains scores of the CPQ8–10 and the number of decayed and missing teeth, respectively. The number of decayed teeth positively correlated with the number of missing teeth and the CPQ11–14 scores. The number of decayed and missing teeth was significantly associated with higher CPQ8–10 scores. Higher CPQ11–14 overall scores were associated with female gender, higher FL domain scores were associated with the number of missing teeth, and higher X50 values and EW domain scores were associated with female gender and the number of decayed teeth. ConclusionsA higher number of missing teeth correlated with an inferior MP in older children. Children with a higher number of caries rated their oral health less favourably. Older females and those who broke the test material into smaller sizes were also more likely to report a worse OHRQoL, suggesting that the time allowed to reduce food appears to be a more influential factor on children’ perception of oral health than their ability to break down the test material into smaller sizes. Moreover, the subjectivity of functional domain and artificial nature of chewable test material could have influenced the test sensitivity.

A STABLE ARTIFICIAL TEST FOOD SUITABLE FOR LABELING TO QUANTIFY SELECTION AND BREAKAGE IN SUBJECTS WITH IMPAIRED CHEWING ABILITY

Color- and form-labeled particles of Optosil (version 1980, a silicone rubber, Bayer, Leverkusen, Germany) have been used previously to quantify the underlying processes of food comminution, i.e., selection and breakage, in subjects with normal dentitions. The aim of this present study was to develop a weakened Optosil that is suitable for the study of selection and breakage in subjects with impaired chewing ability. Half cubes (4.8 × 9.6 × 9.6 mm) were subjected to load tests to determine the force, deformation and work at particle fracture for periods of up to 6 months. Methods of modifying Optosil were (1) heat-treating the base material to produce “Optosoft”; (2) mixing the base of Optosil or Optosoft with a nonprescribed catalyst (Verone, Davis Schott Lander & Davis Ltd, Herts, England) to produce “Optoweak” or “Optosoft-weak” and (3) heating half cubes that were preweakened. A weakened and stable test food that is suitable for labeling and reuse has been obtained by color-dyeing the Optosoft base and using Verone (“dyed-Optosoft-weak”). PRACTICAL APPLICATIONS Every chewing cycle begins with selection, in which food particles have a chance to be placed between the teeth in such a way that they are at least damaged, if not broken, by the subsequent breakage process. Bite force is reduced in certain patients, e.g., patients with neuromuscular diseases, following orthognathic surgery and in full denture wearers, and the action of the tongue and cheeks differs when compared with healthy individuals. Both factors are important in selection and breakage. The artificial test food Optosil has a large fracture force so that it is difficult to chew for subjects with an impaired chewing ability. This problem has been solved by developing a weaker test food, i.e., “dyed-Optosoft-weak.” This test food allows the study of selection and breakage in general with color- and form-labeled particles and to determine the effect of medication, orthognathic surgery or oral implants on these processes.