Showing papers on "Bite force quotient published in 1994"
TL;DR: Recommendations for the amount of fixation required for a given fracture may be reduced after it was found that molar bite forces in patients were significantly less than in controls for several weeks after surgery.
174 citations
TL;DR: The high bite forces of patients with severely worn dentition, especially in the incisal area, can probably be explained by strong masticatory muscles and mechanically favorable skull morphology, which in its turn has been influenced by the surrounding muscles.
Abstract: Patients with severely worn dentition were interviewed and clinically examined, and only those were included who had no or minimal subjective symptoms or clinical signs of craniomandibular disorder. During a 14-month screening period, only 7 patients fulfilled the inclusion criteria; all were men. Maximal bite force was measured in the molar regions and in the incisal region. Facial morphology was evaluated from lateral cephalometric radiographs, and the form of dental arches from dental casts. Average maximal bite force in the molar region was 911 N and in the incisal region 569 N. The most characteristic findings concerning bite force were the high force levels in the incisal region and an incisal/molar bite-force ratio of 63%. The facial morphology of the patients was rectangular, with an anteriorly rotated mandible, small anterior face height, and great interincisal angle. Moreover, the form of the maxillary dental arch was more rectangular than normal. The high bite forces of these patients, especially in the incisal area, can probably be explained by strong masticatory muscles and mechanically favorable skull morphology, which in its turn has been influenced by the surrounding muscles.
87 citations
TL;DR: Correlations were generally not present or were very weak between masticatory performance, estimatedmasticatory forces, and muscle efficiency, suggesting that muscle efficiency and forces generated during mastication are not the primary factors that determine masticatories performance.
78 citations
TL;DR: The magnitudes and directions of the principal components of strain on the four surfaces of the condylar process of human cadaver mandibles during loading with selected simulated muscle forces were determined, with simultaneous measurement of occlusal and joint forces.
71 citations
TL;DR: It is concluded that the direction of a bite force, not its magnitude, determines the pattern of activity of jaw-closing muscles.
Abstract: Human individuals were hypothesized to use the same pattern of jaw muscle activity to produce the same bite force. To test this hypothesis, we used a 2-mm-thick force transducer to monitor the magnitude and direction of a bite force between a single pair of occluding first molars. Five subjects performed standardized bite force tasks. Six different magnitudes were tested, each in five directions. The surface electromyographic (EMG) activity in the left and right masseter and temporalis muscles was recorded, integrated, and normalized. Ratios of the EMG activity of paired muscles (e.g., the ratio of working temporalis and working masseter) were calculated for each bite force task. Each ratio was roughly constant for each direction of bite force, regardless of its magnitude. In contrast, when the magnitude of bite force was the same but the directions were different, the ratio was not constant. We conclude that the direction of a bite force, not its magnitude, determines the pattern of activity of jaw-closi...
62 citations
TL;DR: Differences in jaw-muscle recruitment rates between males and females were best explained by differences in muscle size, and posterior temporalis recruitment patterns seemed to reflect jaw position more closely than mechanical advantage.
55 citations
TL;DR: Biting force significantly affected condylar movement and when taking a centric relation record, a technique involving an anterior stop and sufficient biting force should seat the condyles more fully.
Abstract: The purpose of this study was to investigate the relationship between different incisal biting forces and condylar seating. Bite force was measured with strain gauges at the incisors in 22 adult subjects. The subjects were positioned with mandibles in retruded centric and with an opening not exceeding the range of hinge axis movement. Condylar movement was measured using standard true hinge axis location procedures. Condylar position was measured with no force, then with bite forces of 4.5 kg, 7.5 kg and a comfortable maximum. Biting force significantly affected condylar movement (p < 0.001). As incisal bite forces increased, so did the amount of condylar seating to an average of 0.49 mm anteriorly and 0.27 mm superiorly using maximum biting force. Therefore, when taking a centric relation record, a technique involving an anterior stop and sufficient biting force should seat the condyles more fully.
45 citations
TL;DR: Bite force showed a significant increase in both single tooth and multiple teeth successive biting trials during the experiments, and tactile sensibility between d 11 and its antagonist was not altered by the maximal bite force trials.
Abstract: The relation of number of teeth to maximal clenching force was tested in 10 healthy female dental students. The maximal force in the interincisal position was tested by spreading the load with individual acrylic splints over a varying number of teeth in the anterior region. In the maxilla, one splint covered teeth 13-23; another covered tooth 11. In the mandible, one splint covered teeth 33-43 in all experiments. The maximal force in the incisal position was measured 10 times, five times with each splint. The maxillary splints were changed in random order. The tactile sensibility of tooth 11 and its antagonists was tested before and immediately after interincisal force measurements. A highly significant difference between maximal forces was seen in comparing biting between a single tooth and multiple teeth. In addition, bite force also showed a significant increase in both single tooth and multiple teeth successive biting trials during the experiments. Tactile sensibility between d 11 and its antagonist was not altered by the maximal bite force trials.
40 citations
TL;DR: Bite forces exerted to incise different foods probably depend more on the food than on the individual's bite capabilities, although, as expected, bite forces were least for chocolate and greatest for apple and toffee.
32 citations
TL;DR: In this paper, the sensory mechanisms underlying oral perception of hardness of silicone elastomers were studied using three approaches: (1) compression between parallel plates up to 10% (2) bite forces of 10 subjects for hardness comparisons.
Abstract: The sensory mechanisms underlying oral perception of hardness of silicone elastomers was studied using three approaches: (1) compression between parallel plates up to 10% (2) Bite forces of 10 subjects for hardness comparisons. (3) Deformations were evaluated during controlled mechanical indentations corresponding to the maximum force previously recorded. Over the mechanical stress range studied, the bite forces remained constant for soft samples and then increased for hard ones, while the resulting deformation followed an opposite variation with a decrease for soft samples and a plateau for hard ones. When considering the hardness comparisons between samples of a given series, the harder sample was detected in 10 pairs out of 17. This detection was obtained under almost constant bite force which shows that deformation should be the sensory clue for hardness perception.
30 citations
TL;DR: In spite of a reduced bite force this group of 90-year olds considered their masticatory ability as good and most of them had no severe signs and symptoms of temporomandibular disorders.
Abstract: A group of 35 90-year old subjects, randomly selected from the gerontologic population study in Goteborg (H-70), were examined with respect to function and dysfunction of the masticatory system. The methods included a questionnaire, clinical examination and recording of bite force endurance and maximal bite force, measured in the central incisor region. Forty percent were edentulous, 29% were partially edentulous and wore a removable denture, while the others were dentate without removable prostheses. Signs and symptoms of temporomandibular disorders were mostly mild and infrequent, except TMJ crepitation which was recorded in 69% of the subjects. Maximal bite force was in general low (mean 94 N) but showed a great individual variation (range 10 to 410 N). Bite force endurance was also very variable (mean 72 s, range 10 to 205 s). None of the 35 subjects reported poor masticatory ability, but 2 said they could not chew all kinds of food. In spite of a reduced bite force this group of 90-year olds considered their masticatory ability as good and most of them had no severe signs and symptoms of temporomandibular disorders.
TL;DR: In this paper, a 14-month screening period, only 7 patients with severely worn dentition were interviewed and clinically examined, and only those were included who had no or minimal subjective symptoms or clinical signs of craniomandibular disorder.
01 Jan 1994
TL;DR: It was found that molar bite forces in patients were significantly less than in controls for several weeks after surgery, indicating that recommendations for the amount of fixation required for a given fracture may be reduced.
Abstract: Voluntary bite forces were recorded at varying periods in 35 males treated with rigid internal fixation for fractures of the mandibular angle. Bite forces were also obtained in 29 male controls for comparison. It was found that molar bite forces in patients were significantly less than in controls for several weeks after surgery. Further, molar bite forces on the side of the fracture were significantly less than on the nonfractured side. The results of this study indicate that recommendations for the amount of fixation required for a given fracture may be reduced. Recommendations for the amount of fixation hardware necessary to treat fractures of the mandibular angle vary widely. For instance, the size of plates (thickness, length, number of holes). diameter and length of screws, and number of plates used for angle fractures differ from one clinician to another. The AO/ASIF recommends that sufficient internal fixation hardware be applied to resist the maximum forces of mastication. By so doing, they hypothesize that stability of the fracture segments is assured even under full function of the masticatory system. However, this necessitates placement of either two plates, one along the superior and one along the inferior borders of the buccal cortex, or a large, thick reconstruction bone plate along the inferior border. Either of these combinations provide ample fixation for a mandibular angle fracture to allow full function. The forces that must be countered in fractures at the mandibular angle have been derived from maximum voluntary bite force measurements, which in a healthy adult male may be in the order of 50 kiloponds (kp).§ A previous study of subjects who sustained zy
TL;DR: An electromyographic study of the masseter and anterior temporal muscles together with questioning patients regarding subjective symptoms was performed and confirms that judgement of level of improvement following treatment of MPD syndrome is more appropriate through objective evaluation.
Abstract: Summary
An electromyographic study of the masseter and anterior temporal muscles together with questioning patients regarding subjective symptoms was performed on 15 patients with myofascial pain dysfunction (MPD) syndrome prior to and during bite plate therapy.
The electromyographic study was evaluated by the slopes of the voltage tension (V/T) curves (calculated as the value of the relative inclination between the integrated electromyram and the biting force). The improvement of subjective symptoms was recognized earlier than the relief of objective symptoms by bite plate therapy. The results confirm that judgement of level of improvement following treatment of MPD syndrome is more appropriate through objective evaluation. Follow-up recording of the voltage tension can be considered to be an objective indicator for patients with MPD syndrome.
Journal Article•
TL;DR: The temporal muscle functions as a jaw positioner more than a force generator at a low clenchinglevel, and at a high clenching level, the temporal muscle increases its function as a force generators.
Abstract: Masticatory muscles perform two functions during clenching, as generating a bite force and maintaining a jaw position. The relationship between these two functions may be changed by the differences of the stability level of the mandibular position and the degree of the bite force.Therefore, we recorded muscle activities of masseter and anterior temporal muscles on seven healthy male subjects during MVC and 30% MVC in three different stability of mandibular position. A metal frame of central bearing type which was fited in a mouth caused variation of the stability level of the mandibular position.“Activity index” and “asymmetry index” were studied, and the results were as follows:1. Activity index in MVC was larger than in 30%MVC.2. Asymmetry index of temporal muscle changed with a stability level of mandibular position in 30% MVC. Temporal muscle could prevent a sliding of the mandibule. This tendency was notfound in MVC.3. Asymmetry index of the masseter muscle did not change with a different stability levels of mandibular position or degrees of bite force.In conclusion, the temporal muscle functions as a jaw positioner more than a force generator at a low clenching level. At a high clenching level, the temporal muscle increases its function as a force generator. The masseter muscle functions as a force generator more than a jaw positioner in every degree of clenching.