• 구강회복응용과학지
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• 제32권1호
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• pp.1-7
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• 2016

저작은 음식을 잘게 부수어 소화작용이 원활하게 진행될 수 있도록 돕는 행위이다. 이러한 저작계는 상하악골, 악관절, 인대, 치아 및 근육으로 구성된다. 교합력은 이러한 저작계를 평가하는 한 가지 수단이다. 교합력은 얼굴형태, 나이, 성별, 치주질환, 측두하악장애, 치아 상태 등에 의해 영향을 받는다. 최대교합력은 방형(square form)의 얼굴이 높으며 일반적으로 남자가 여성보다 높다. 또한 20세정도까지 증가하며 그 이후부터 40 - 50세까지 거의 일정하게 유지되다가 감소하는 경향을 보인다. 치주질환이 있을 경우 교합력 감소에 영향을 주며 측두하악장애의 경우 교합력의 영향에 논란이 있다. 치아의 상태가 최대교합력에 영향을 미치는 중요한 인자로 생각된다.

• 대한치과교정학회지
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• 제40권5호
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• pp.304-313
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• 2010

본 연구는 한국인 정상교합자와 부정교합자 사이의 교합력의 크기와 교합 시의 접촉 면적의 차이 및 골격 형태와 교합 관계, 연령, 성별이 교합력의 크기에 영향을 미치는지 알아보기 위해 시행되었다. 정상교합자 15명, 부정교합자 636명에서 일회용 pressure sensitive sheet (Dental $Prescale^{(R)}$ 50H, typeR, Fuji Film Corp., Tokyo, Japan)를 자연 두부위에서 최대 근력으로 교합하도록 한 후, CCD camera ($Occluzer^{(R)}$ FPD 707, Fuji Film Corp., Tokyo, Japan)로 판독하여 교합력의 크기 및 접촉 면적을 측정하였다. 정상교합자군의 교합력의 크기는 $744.5{\pm}262.6N$, 접촉면적은 $24.2{\pm}8.2mm^2$으로, 부정교합자군의 $439.0{\pm}229.9N$, $12.4{\pm}10.7mm^2$에 비해 교합력의 크기와 접촉 면적이 유의하게 컸다 ($p$ < 0.05). 부정교합자군의 경우 연령에 따른 교합력의 차이는 없었으나, 남자가 여자에 비해 큰 교합력을 가지고 있었다 ($p$ < 0.05). 악안면의 전후방적인 골격 형태를 나타내는 ANB 및 골격성 1급 부정교합에서의 구치부의 Angle 분류는 교합력에 유의한 차이를 나타내지 않았으나, 수직적인 골격 형태를 구분하는 mandibular plane angle, gonial angle이 큰 경우, 교합력이 유의하게 작았다 ($p$ < 0.05). 하지만, 교합력의 크기와 접촉 면적간에는 높은 상관관계가 존재하는 점과 접촉 면적을 통제한 상태에서의 골격 형태와 교합력의 크기 사이에는 유의할 만한 상관관계가 없는 점을 고려한다면 수직적인 골격 형태가 직접적으로 교합력에 영향을 주기보다는 수직적인 골격 형태에 따른 접촉 면적의 감소가 교합력 저하에 관여한다고 판단된다.

• 대한치과교정학회지
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• 제26권1호
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• pp.95-104
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• 1996

본 연구의 목적은 T-Scan system과 근전도를 이용하여 정상교합자와 과개교합자의 최대교합력과 근활성도간의 상관관계를 조사하기 위함이다. 연구대상은 두 집단으로 구성 되었다. 한 집단은 20명의 정상교합자이고 다른 집단은 30명의 과개교합자이다. 과개교합자는 Class I deepbite(9명의 남자와 7명의 여자)와 Class II div. 1 deepbite(8명의 남자와 6명의 여자)로 구성되었다. 이 연구로부터 얻어진 결과는 다음과 같다. 1. 최대교합력은 정상교합군에서 155.93 N, I급 과개교합군에서 165.11 N, II 1류 과개교합군에선 111.55 N이었으며, II급 1류 과개교합군의 최대교합력은 정상교합군에 비해 유의성 있게 낮았다(P<0.01). 2. 정상교합군과 과개교합군 모두에서 치야접촉점이 증가할수록 교합력은 증가하였다(표 3). 3. 최대교합시 II급 1류 과개교합군의 교근 및 전측두근의 근활성도는 전상교합군에 비해 현저히 낮았고(P<0.01),모든 군에서 교근의 활성도가 전측두근보다 높았다(P<0.05). 4. 모든 군에서 교합력과 근활성도, 치아접촉점의 수와 근활성도는 높은 상관관계를 보였다(표 5).

• Maxillofacial Plastic and Reconstructive Surgery
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• 제14권4호
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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.

• 한국정밀공학회지
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• 제27권4호
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• pp.87-94
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• 2010

When occlusal force is applied to a tooth, stress concentration occurs on the dental cervical line. This study investigated to find the maximum force and strain of natural teeth using an Instron and strain gauges, comparing the strain of cervical enamel using finite element analysis(FEA). Tests were conducted with a mandibular first premolar applying the conditions of occlusion. Then, the FEA was processed with the same as conditions of the fracture test. The test showed that the maximum force, maximum compressive strain and maximum tensional strain was $278{\pm}26$ N, $0.668{\times}10^{-3}{\pm}0.678{\times}10^{-3}$ and $0.248{\times}10^{-3}{\pm}0.102{\times}10^{-3}$, respectively. It was found that six of eight measured strains were within the range of estimated strains by the FEA. Even though it was assumed that properties of FE models were isotropic, it could prove useful as a reference in understanding the tendency of dental strain.

• 대한치과의사협회지
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• 제13권12호
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• pp.1135-1139
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• 1975

A boy aged 13 years 5 months, had a Angle's clss I malocclusion characterized by severe anterior crowding. Molar relationship was neutroclusion, incisor overbite was 4mm, incisor overjet was 3mm. The patient underwent extraction of four first premolars and was treated with a multi-banded light force system. On the process of the orthodontic treatment, the teeth, obtained functional occlusion. The result of treatment was very satisfactory; color, vitality and mobility were normal, periodontal condition was good and the cosmetic result was excellent.

• 대한치과의사협회지
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• 제53권5호
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• pp.307-317
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• 2015

Although the long-term success of osseointegrated endosseous implants for the support of fixed dental prostheses has been reported, the increasingly widespread use of implant-supported prostheses has led to problems associated with their structural integrity. The most common biomechanical complications observed in dental implant treatment are fracture and screw loosening. The nature of loosening or fracture of dental implant components is complex, since it involves fatigue, fitness, and varied chewing patterns and loads. To assess the service life of the components of the prosthetic system, a knowledge of the loads transmitted through the system is necessary. Design of the final restoration and occlusion in relation to the geometry of a prosthetic restoration has a great influence on the mechanical loading of the implant. It is proposed that control of force in oral cavity may play a larger role in failures than previously believed. Based on theoretic consideration and clinical experiences with dental implant, this article gives simple guidelines for controlling these loads.

• 대한치과교정학회지
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• 제53권1호
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• pp.54-64
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• 2023

This case report describes skeletal anchorage-supported maxillary protraction performed with the Alternate Rapid Maxillary Expansion and Constriction (AltRAMEC) protocol over a treatment duration of 14 months in a 16-year-old female patient who was in the late growth-development period. Miniplates were applied to the patient's aperture piriformis area to apply force from the protraction appliance. After 9 weeks of following the Alt-RAMEC protocol, miniplates were used to transfer a unilateral 500-g protraction force to a Petit-type face mask. A significant improvement was observed in the soft tissue profile in measurements made both cephalometrically and in three dimensional photographs. Subsequently, the second phase of fixed orthodontic treatment was started and the treatment was completed with the retention phase. Following treatment completion, occlusion, smile esthetics, and soft tissue profile improved significantly in response to orthopedic and orthodontic treatment.

• 구강회복응용과학지
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• 제20권1호
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• pp.43-50
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• 2004

This study was performed to measure the retentive force of dental impression tray according to retention form. The 9 resin beams($30{\times}60{\times}2.5mm$) were made of visible light-curing tray resin according to the surface texture, the size of hole and the number of rim. The resin block was fabricated in width 50mm, length 30mm, heght 40mm to maintain an even hydrocolloid impression material. The retentive force between the resin beam and hydrocolloid impression material was measured by Universal Testing Machine(Zwick Z020, Zwick Co., Germany). The results obtained in this study were as follows : 1. The retentive force of the resin beam with bilateral 4 rims, 2mm holes(9group) was highest(9.18kg), and the polishing resin beam(2group) was worst(4.85kg). 2. There was no significant difference between the polished the resin beam(2group) and the contrast resin beam(1group). 3. The retentive force of the rimmed resin beam was higher than the perforated resin beam. 4. The retentive force of the 2mm perforated resin beam(4group) was higher than the 3mm perforated resin beam(3group). 5. As increasing the number of rim increased the retentive force.

• 구강회복응용과학지
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• 제22권1호
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• pp.11-21
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• 2006

The adjustable dental impression trays were made for being adjusted their width automatically along the width of patient's dental arch. The purpose of this study was to investigate the retentive force of adjustable dental impression trays made of different synthetic resin materials. Three pairs of adjustable trays were made of ABS(acrylonitrile butadiene styrene) synthetic resin, polyurethane synthetic resin and polycarbonate synthetic resin with a hole and without a rim on the border area of them. The experiment was done with the horse-shoe shaped metal plate to pull out the set impression body from the tray jig which was made for holding the tray on the lower part of Universal Testing Machine(UTM, Zwick Z020, Zwick Co., Germany). After the alginate impression in the tray was allowed to set four minutes, a tensile force was applied at right angles to the tray which had been previously seated on the jig. The force was applied to measure a maximum force by use of UTM at a constant strain rate 100mm per minute. The results obtained in this study were as follows : 1. The upper trays were showed higher retentive force than lower trays in three tray materials. 2. There was no significant difference in the retentive force of the tray materials(p>0.05).