• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.1
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• pp.1-7
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• 2016

Mastication is the process to help digestion by chewing or grinding food. Masticatory system consists of maxilla, mandible, temporomandibular joints, ligaments, dentitions, and musculatures. Assessing the bite force can be one of the methods to estimate the masticatory system. Bite force is influenced by facial morphology, age, sex, periodontal status, temporomandibular joint disorder and dental condition, and so forth. In general, higher maximum bite force is seen in those who have a square-shaped face and in male rather than female. In addition, bite force tends to be increased by age 20, maintained constantly until age 40 - 50, and then decreased. Periodontal disease is known as a causative factor for decreased bite force while temporomandibular disorder (TMD) remains controversial as to whether it affects the force. The status of teeth is considered as an important factor to determine the maximum bite force.

• The korean journal of orthodontics
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• v.33 no.6 s.101
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• pp.437-451
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• 2003

The purpose of this study was to measure maximum bite force and to investigate its relationship with anteroposterior, vertical, and transverse facial skeletal measurements. From among the dental students at the College of Dentistry, forty subjects (26 male and 14 female) were selected. With two sets of strain gauge, maximum bite force at the right and left first molars and anterior teeth was measured in the morning and afternoon. After taking lateral and posteroanterior cephalograms, fifty and nineteen variables were evaluated, respectively Paired t-tests and an independent t-test were done and correlation coefficients were obtained. 1. The maximum bite force at the first molars was $68.0\pm13.9kg$. in males and $55.6\pm10.5kg$ in females (p<0.05) while the force at the anterior teeth was $8.4\pm4.9kg\;and\;1.1\pm3.4kg$ respectively (p<0.05). 2. Some tendency for a greater value of maximum bite force at the preferred side was observed but not statistically significant (p>0.05). 3. Significant difference was observed between the strong bite force group and the weak bite force group in some cephalometric and other measurements (p<0.05). N-S-Ar, S-Ar-Go, FH-Hl, IMPA and MMO showed a significant difference in posterior maximum bite force (P). N-S-Ar and FH-H1 also showed a significant difference in anterior maximum bite force (A). 4. Several cephalometric variables showed some correlation with maximum bite force (p<0.05). N-S-Ar, S-Ar-Go, UGA, FH-H6, FH-H1, body weight and MMO were significantly correlated with posterior maximum bite force (P). Go-Me, P-1 and IMPA were significantly correlated with anterior maximum bite force (A).

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.1
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• pp.103-111
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• 2006

Statement of problem: The previous unilateral bite force recorder has several limitations for taking long time for measuring and causing discomfort to subjects. Because of these reasons, it could not use widely for epidemiological researches. However, 'Dental Prescale System' which is new equipment for measuring bite force, is more convenient for measuring bite force than previous unilateral recorder. Purpose: The purpose of this study was to compare a new technique(Dental Prescale System) using pressure sensitive foils for recording of maximal jaw closing force with conventional measurement using unilateral bite force recorder Material and method: This studies included 22 healthy dental students in college of dentistry Yonsei university in Rep of Korea. Mean age was 23.9 years. All subjects had continuous dental arches and no significant malocclusion or signs from the teeth and craniomandibular system. The Dental Prescale System (Fuji Film, Tokyo, Japan) consists of a horseshoe-shaped pressure sensitive sheet (50H, R type) and a computerized scanning system.(FPD705) We also used unilateral bite force recorder(Denbotics Co. Seoul, Rep.Korea) for comparing with Dental Prescale. Results and conclusion: The total bite force recorded with Dental Prescale System (1423 N) was systematically higher than that recorded by unilateral bite force recorder. (256 N) However, the maximum bite force values measured in the two ways were significantly correlated (r=0.46, p<0.05). The Dental Prescale bite force calculated for first molar (208 N) was lower than that recorded by unilateral bite force recorder. (256 N) The two values were also very significantly correlated. (r=0.66. p<0.001) There were significantly different in bite force between two measurement methods. The reasons were first, unilateral bite force recorder measured only the bite force of a part of teeth, and Dental Prescale measured the total teeth force. Second, in measurement, a difference in muscle contraction appeared by an extent of mouth-opening. Third, unilateral bite force recorder has the reducing effect of the bite force by protective tape. Fourth, Dental Prescale has limitations during the computer scanning procedure. Therefore, Dental Prescale System is considered to be a very promising alternative to be conventional bite force recording methods.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.14 no.4
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• pp.327-339
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• 1992

This study was undertaken to investigate the effect of orthognathic surgery on occlusal force. The maximum bite force was measured in 26 dentofacial deformity patients, aged 14-26(mean age 20.3) years, before surgery and at IMF removal, 3, 6, and 12months postsurgery. To grope the correlation of bite force and skeletal change after orthognathic surgery, the cephalometric headplates were measured, tabulated and statistically analyzed. The results were as follows. 1. The presurgical maximum bite force was 13.7kg in upper first molar(rt. Side 12.7kg, it. Side 14.6kg). There was remarkable difference with that of normal occlusion. 2. The recovery of bite force was very significant in according to the operation method and the duration of IMF that was 7.6kg at IMF removal, 14.2kg at 3 months, 19.7kg at 6 months. 26.1kg at 12 months postsurgery. 3. To fasten the recovery and to increase the bite force after orthognathic surgery, the long IMF time and the injury to the masticatory muscle should be avoided by the internal rigid fixation and early physical exercise. 4. The bite force was positively correlated to the changes of mandibular plane angle, the angle between platatal plane and mandibular plan, the angle between occlusal plane and mandibular plane, and negatively correlated to the changes of mandibular body length in craniofacial structure. 5. There was no correlationship between bit force and mesial inclination of tooth long axis of first molar in this subject. 6. There was no correlation between the changes of bite force and the changes of mechanical advantage of the temporal and masseter muscle.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.4
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• pp.204-212
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• 2022

Purpose: The aim of this study was to compare changes of bite force, occlusal contact area, and dynamic functional occlusion analysis after occlusal stabilization splint therapy during sleep for one month in a patient with bruxism. Materials and Methods: From October 2021 to July 2022, sleep bruxism of 30 patients who visited the Department of Oral Medicine at Yonsei University College of Dentistry Hospital were recruited. The participants were divided into two groups: using an occlusal stabilization splint during sleep (treatment; n = 15) and not using an occlusal stabilization splint (control; n = 15). Before using the occlusal stabilization splint and one month after, bite force, occlusal contact area and dynamic functional occlusion analysis (ratio of left/right bite forces, average bite forces, maximum bite forces, and maximum contact areas during lateral and anterior and posterior mandibular movements) were performed. Results: There was no difference in bite force and occlusal contact area between the treatment group using the occlusal stabilization splint and the control group not using the occlusal stabilization splint during sleep for one month. However, there were significant differences in the average bite force and maximum bite force in the lateral and anterior and posterior mandibular movements and the maximum contact areas in the anterior and posterior mandibular movements. Conclusion: The occlusal stabilization splint is helpful for sleep bruxism patients who lateral and anterior and posterior mandibular movements. In addition, further studies are needed a double-blind study with a large population.

• The korean journal of orthodontics
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• v.26 no.1 s.54
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• pp.95-104
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• 1996

This study was undertaken to investigate the correlations bite force and the electromyographic activities of masticatory muscle in deepbite, using the T-Scan system and electromyograph. The subjects of this study consisted of two groups ; one of 20 individuals with normal occlusion, the other group of 30 with deepbite. The deepbite was composed of Class I deepbite(male 9, female 7) and Clas II div. 1 deepbite(male 8, female 6). The obtained results of this study were as follows : 1. The maximum bite force was 155.93 N in normal occlusion, 165.11 N in Class I deepbite group, 111.55 N in Class II div. 1 deepbite group. 2. The greater !he number of tooth contacts, the more the bite force increased in all groups. 3. During maximum clenching, masseter and ant. temporailsmuscle activity of normal and Class I deepbite group were significantly higher than that of Class II div. 1 deepbite group, and the activity of masseter muscle was higher than that of ant. temporalis muscle in all groups. 4. The greater the maximum bite force, the more the muscle activities increased in all groups.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.5
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• pp.537-542
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• 2008

BSSRO is most frequently operated among orthognathic surgery techniques for repairment of maxillofacial deformities. In case of patients with maxillofacial asymmetry accompanying mandibular protrusion who are operated by BSSRO, this study considers the recovering time for masticatory force of each tooth and Masseteric EMG and the adequate time enabling normal occlusion. The patients who are operated with BSSRO under general anesthesia in Dankook Dental Hospital, Department of OMS are selected for this study. The control group is devided into 2. 26 patients with facial asymmetry accompanying mandibular protrusion are selected for group 1 and their maximum voluntary bite force and masseteric EMG are measured. Group 2 is formed by volunteers with healthy dentition who are measured maximum bite force and masseteric EMG on both sides of the mouth. At the week of 3rd, 5th, 7th, 9th and 11th, Mann-Whitney U test is carried on for statistical analysis and the result is as follows. 1. Patients with mandibular protrusion showed apparently low maximum bite force and masseteric EMG than patients with normal occlusion. 2. In comparison with control group 1, Occlusal force is regained in incisors and canines at the 9th week and in premolars and molars, 11th week and masseteric EMG is regained at 11th week. 3. Comparing to normal occlusal patients, no recovery could be found in experimental group in every parts of the mouth.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.6
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• pp.591-601
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• 2008

STATEMENT OF PROBLEM: The improvement in oral function and comfort from the dental implant appears to depend on the particular type of implant support used with the denture. The number and positioning of implants have an influence on the force transfer and subsequent stress distribution around implants. Nevertheless, a quantitative comparison has not been made between the types of implant prosthesis used with different materials compared to conventional complete denture. PURPOSE: The objective of this study is to assess the masticatory performance, bite force and impact of two different type of implant supported prostheses on oral health-related quality of life compared to conventional complete denture with GOHAI, validated oral-specific health status measures, the sieving method, and the Prescale Dental System. MATERIAL AND METHODS: From the years 1999 to 2006, a total of 30 completely edentulous patients in a single arch were selected from the Yonsei University Dental Hospital, Department of Prosthodontics and Implant Clinic in Seoul, S. Korea. Patients were divided into 3 groups of 10 each. Group HR was restored with fixed-detachable hybrid prostheses with resin teeth. Group FP had fixed dentures with porcelain teeth while Group CD had a complete denture. The masticatory performance was compared between 3 groups. RESULTS: The results showed a significant improvement in oral health-related quality of life with dental implants compared to a conventional denture in GOHAI comparison. Overall, implant prostheses showed a higher masticatory performance ($S_{50}$) and maximum bite force compared with conventional dentures (P < .05) but no differences between different implant supported prostheses (P > .05). CONCLUSION: Within the limitation of this study, the numbers of implant and material of implant prostheses does not appear to impact patient satisfaction, masticatory performance or bite force.

• The korean journal of orthodontics
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• v.25 no.3 s.50
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• pp.311-321
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• 1995

This study was undertaken to investigate the distribution of the chewing side preference and variations in the maximum bite force and facial morphology according to chewing side preference since unilateral chewing may cause morphologic and functional anomalies. 50 dental students who had no signs or symptoms of masticatory system and Angle's Class I relationship in posterior segments were selected, and divided into two groups, that is, 25 in bilateral chewing group(19 male and 6 female) and 25 in unilateral chewing group(10 male and 15 female). Maximum bite force was estimated ana posteroanterior cephalogram were measured ana statistically analyzed. The results were as follows : 1. Their were more students with bilateral chewing side preference($68\%$) and unilateral chewing side group consisted of right side preference($68\%$) and left side preference($32\%$). 2. There was no significant difference in the strength of max. bite force between the right and left side in bilateral chewing group. The bite force of the chewing side nab greater in the unilateral chewing group but less in the non-chewing side compared to those of bilateral chewing group with Bo significant difference. Max. bite force of chewing side was greater than that of non-chewing side in the unilateral chewing group(Female p<0.05). Max. bite force of males was about twice in that of females in both groups(p<0.05). Max. bite force of chewing side of the unilateral chewing group was similar to that of the bilateral chewing group, but that of non-chewing side was less than that of the bilateral chewing group. 3. In comparison of the facial morphology, there was no statistically significant difference in the size between the right and left side of the bilateral chewing group and between chewing and non-chewing side of the unilateral chewing group.

• The korean journal of orthodontics
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• v.43 no.5
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• pp.218-224
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• 2013

Objective: To examine the effect of bite force on the displacement and stress distribution of orthodontic mini-implants (OMIs) in the molar region according to placement site, insertion angle, and loading direction. Methods: Five finite element models were created using micro-computed tomography (microCT) images of the maxilla and mandible. OMIs were placed at one maxillary and two mandibular positions: between the maxillary second premolar and first molar, between the mandibular second premolar and first molar, and between the mandibular first and second molars. The OMIs were inserted at angles of $45^{\circ}$ and $90^{\circ}$ to the buccal surface of the cortical bone. A bite force of 25 kg was applied to the 10 occlusal contact points of the second premolar, first molar, and second molar. The loading directions were $0^{\circ}$, $5^{\circ}$, and $10^{\circ}$ to the long axis of the tooth. Results: With regard to placement site, the displacement and stress were greatest for the OMI placed between the mandibular first molar and second molar, and smallest for the OMI placed between the maxillary second premolar and first molar. In the mandibular molar region, the angled OMI showed slightly less displacement than the OMI placed at $90^{\circ}$. The maximum Von Mises stress increased with the inclination of the loading direction. Conclusions: These results suggest that placement of OMIs between the second premolar and first molar at $45^{\circ}$ to the cortical bone reduces the effect of bite force on OMIs.