• Imaging Science in Dentistry
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• 제45권1호
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• pp.61-65
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• 2015

The mental foramen is a bilateral opening in the vestibular portion of the mandible through which nerve endings, such as the mental nerve, emerge. In general, the mental foramen is located between the lower premolars. This region is a common area for the placement of dental implants. It is very important to identify anatomical variations in presurgical imaging exams since damage to neurovascular bundles may have a direct influence on treatment success. In the hemimandible, the mental foramen normally appears as a single structure, but there are some rare reports on the presence and number of anatomical variations; these variations may include accessory foramina. The present report describes the presence of accessory mental foramina in the right mandible, as detected by cone-beam computed tomography before dental implant placement.

• 대한소아치과학회지
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• 제46권2호
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• pp.183-189
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• 2019

이 연구는 6 - 13세의 혼합치열기 및 초기 영구치열기 소아의 파노라마를 이용하여 연령의 변화에 따른 이공의 위치의 변화를 알아보고자 하였다. 원광대학교 치과대학병원에 내원한 180명을 대상으로 촬영된 파노라마를 수집하였고, Piview(Infinitt, Korea) 프로그램을 사용하였다. 이공의 경우 수평적으로는 치아의 대한 상대적 위치와, 수직적으로는 이공의 중심을 지나는 치조정에서 하악하연까지의 거리와 이공의 중심에서의 하악하연까지의 거리의 비를 계산하여 이공의 위치를 평가하였다. 이공은 하악체에서 전후방적으로 제2유구치(제2소구치) 근심부에 가장 많이 위치하였으며, 제1유구치의 원심부위에 위치하였다가 연령의 증가에 따라 후방으로 이동하였고, 수직적으로는 치조골의 1/2 지점 보다 약간 하방에 위치하였으며 연령의 증가에 따라 하방으로 이동하였고 연령과 유의한 상관관계를 보였다.

• The Journal of Advanced Prosthodontics
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• 제9권6호
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• pp.470-475
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• 2017

PURPOSE. The purpose of this study was to identify the complex course of the mandibular canal using 3D reconstruction of microCT images and to provide the diagram for clinicians to help them understand at the interforaminal region in Korean. MATERIALS AND METHODS. Twenty-six hemimandibles obtained from cadavers were examined using microCT, and the images were reconstructed. At both the midpoint of mental foramen and the tip of anterior loop, the bucco-lingual position, the height from the mandibular inferior border, the horizontal distance between two points, and position relative to tooth site on the mandibular canal were measured. The angle that the mental canal diverges from the mandibular canal was measured in posterior-superior and lateral-superior direction. RESULTS. The buccal distance from the mandibular canal was significantly much shorter than lingual distance at both the mental foramen and the tip of anterior loop. The mandibular canal at the tip of anterior loop was significantly located closer to buccal side and higher than at the mental foramen. And the mental canal most commonly diverged from the mandibular canal below the first premolar by approximately $50^{\circ}$ posterior-superior and $41^{\circ}$ lateral-superior direction, which had with a mean length of 5.19 mm in front of the mental foramen, and exited to the mental foramen below the second premolar. CONCLUSION. These results suggest that it could form a hazardous tetrahedron space at the interforaminal region, thus, the clinician need to pay attention to the width of a premolar tooth from the mental foramen during dental implant placement.

• Imaging Science in Dentistry
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• 제31권3호
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• pp.153-158
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• 2001

Purpose : To determine the head position that the superior border of the mandibular canal as well as mental foramen can be more clearly visualized in panoramic radiography Materials and Methods : Ten dry mandibles were radiographed bilaterally using PM 2002 CC panoramic machine. A 20 mm thick aluminium filter was added to the slit collimator to obtain radiographs with acceptable density. The specimens were tilted by 2, 4, 6, 8, and 10 degrees downward with and without radiopaque markers. Radiopaque markers were inserted into the mandibular canals and the mental canals of each side of the specimens to serve as reference image when assessing the radiographs. The visibility of the mandibular canal and the mental foramen was estimated by 4 observers on all radiographs. The obtained results were analyzed statistically. Results: Mandibular canals were significantly more clearly visible in the radiographs with 4 and 6 degree downward position on both sides (P<0.05). Mental foramens were significantly more clearly visible in the radiographs with 4, 6, and 8 degree downward on right side and 6 degree downward on left side (P<0.05). There was not significant difference between right and left sides. Conclusion: Panoramic radiographs with 4 to 6 degree downward tilting could be valuable in locating the mandibular canal as well as the mental foramen.

• 구강회복응용과학지
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• 제27권3호
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• pp.317-326
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• 2011

이공과 하악관 전방고리는 악골의 외과적 술식에서 중요한 기준점이 된다. 이번 연구의 목적은 전산화단층촬영를 이용해 이공과 하악관 전방고리의 형태를 분석하고, 이를 임상에 적용하기 위함이다. 외과적 수술이 계획된 96명(남성 33명, 여성 63명, 연령범위 17 ~ 43세, 평균연령 $24.6{\pm}4.99$세)의 환자를 대상으로 전산화단층촬영을 시행하였다. 전산화단층촬영 방사선영상에서 이공의 수평적, 수직적 위치, 치근첨과의 거리를 측정하였고, 하악관 전방고리는 치근첨에서의 거리, 협측 측방각도를 측정하였다. 이공의 위치는 하악 제2소구치 하방이 81례(46.0%)로 가장 많았으며, 하악 제1소구치와 제2소구치사이에 존재하는 경우는 67례(38.0%)로, 하악 제2소구치와 제1대구치 사이에 존재하는 경우는 19례(10.2%)로 나타났다. 이공과 하악골 하연과의 평균거리는 $12.20{\pm}1.77$ mm, 이공과 치근첨과의 평균거리는 $5.16{\pm}0.98$ mm. 하악관 전방고리의 평균 길이는 $5.80{\pm}2.00$ mm로 나타났다. 하악관 전방고리에 대한 협측 각도는 $47.7{\pm}9.07^{\circ}$로 나타났다. 치근첨과 이공과의 거리는 파노라마 영상에서는 $5.16{\pm}0.98$ mm로 나타났고, 전산화단층촬영영상에서는 $6.2{\pm}3.07$ mm로 나타났다. 이공과 하악관의 평균거리는 $5.39{\pm}1.62$ mm로 나타났다. 임플란트를 포함한 악골의 외과적 술식에서 이신경의 손상 및 외과적 외상의 위험을 최소화하고 최적의 수술결과를 얻기 위해서는 이공과 하악관 전방고리의 형태와 위치에 대한 정확한 평가가 이뤄져야 한다. 전산화단층촬영 영상은 이러한 해부학적 구조를 찾는데 유용할 것으로 생각된다.

• International Journal of Oral Biology
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• 제37권1호
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• pp.25-29
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• 2012

During maxillofacial surgery, the infraorbital and mental nerves are blocked at eac foramen to induce local anesthesia. This study examined the relative locations of the infraorbital foramen (IOF) and mental foramen (MF) based on softtissue landmarks. Twenty-eight hemifacial cadavers were dissected to expose the IOF and MF. The distances between the bilateral IOFs, the bilateral MFs, the alae of the nose (alares), and the corners of the mouth (cheilions) were measured directly on cadavers by using a digital vernier caliper. The vertical and horizontal distances of the IOF and MF relative to the alare and cheilion were measured indirectly on digital photographs using Adobe Photoshop (Adobe, CA, USA). The distance between the bilateral IOFs ($58.09{\pm}4.04mm$) was longer than the distance between the bilateral MFs ($50.32{\pm}1.93mm$). The distances between the bilateral alares and cheilions were $41.22{\pm}3.44mm$ and $58.43{\pm}6.62mm$, respectively. The IOF was located $12.92{\pm}3.75mm$ superior and $7.88{\pm}2.56mm$ lateral to the alare, and the vertical angle (Angle 1) between these structures was $31.67{\pm}13.36^{\circ}$ superolaterally. The MF was located $21.83{\pm}3.26mm$ inferior and $5.56{\pm}3.37mm$ medial to the cheilion, and the vertical angle (Angle 2) between these structures was $14.05{\pm}10.12^{\circ}$ inferomedially. In conclusion, these results provide more detailed information about the locations of the IOF and MF relative to soft-tissue landmarks.

• Imaging Science in Dentistry
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• 제54권1호
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• pp.115-120
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• 2024

Components derived from an infected lesion within the bone can spread through various passages in the mandible, particularly via the mental foramen. Radiologically, the spread of infection is typically nonspecific and challenging to characterize; however, multislice computed tomography (MSCT) can effectively detect pathological changes in soft tissues and the bone marrow space. This report describes the case of a 55-year-old woman who experienced mental nerve paresthesia due to a periapical infection of the right mandibular second premolar. MSCT imaging revealed increased attenuation around the periapical lesion extending into the mandibular canal and loss of the juxta-mental foraminal fat pad. Following endodontic treatment of the tooth suspected to be the source of the infection, the patient's symptoms resolved, and the previous MSCT imaging findings were no longer present. Increased bone marrow attenuation and obliteration of the fat plane in the buccal aspect of the mental foramen may serve as radiologic indicators of inflammation spreading from the bone marrow space.

• 치과방사선
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• 제27권1호
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• pp.189-201
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• 1997

22세에서 25세의 남녀 각각 100명씩 200명을 대상으로 표준 위치에서 촬영된 파노라마 방사선사진상에서 이공의 정상적 형태 및 위치를 분석하고, 다시 남녀 각각 50명씩 100명을 선별하여 두부를 10mm 전방 이동, 10mm 후방 이동, 10° 하방 이동, 그리고 10° 상방 이동시킨 후 촬영된 각각의 파노라마 방사선사진상에서 피사체의 위치 변화에 따른 이공의 형태 및 수평, 수직적 위치의 변화를 평가하여 다음과 같은 결과를 얻었다. 1. 이 공의 형 태 는 elliptic질형 (43.3％), round 또는 oval형 (42.5％), unidentified형 (7.5％), diffuse형(6.7％)의 순으로 관찰되었다. 2. 이공이 치아에 대한 수평적 위치는 제2소구치 부위(54.2％)와 제1소구치와 제2소구치 사이 (43.1％)에서 대부분 관찰되었으며, 제2소구치와 제1대구치 사이(2.7％)의 순으로 관찰되었고, 제1소구치 부위, 견치와 제1소구치 사이, 제1대구치 부위에서는 관찰되지 않았다. 3. 이공의 수직적 위치는 치근단 하방(88.2％)에서 대부분 관찰되었으며, 치근단에 접하는 경우(9.7％), 치근단과 겹쳐 나타난 경우(1.9％), 치근단에 비해 상방에 위치하는 경우(0.2％)의 순으로 관찰되었다. 4. 피사체 두부 위치의 변화에 따른 이공의 형태 변화는 표준 위치에서 나타난 결과와 비교해 볼 때 표준 위치에서 두부를 10mm전방 이동시킨 위치에서 unidentified형(9.0％)이 증가하였고, 두부를 10mm 후방 이동시 킨 위치와 피사체의 턱을 10° 상방 이동시킨 위치에서는round 또는 oval형(57.5％, 52.5％)이 각각 증가하였으며, 피사체의 턱을 10° 하방 이동시킨 위치에서는 diffuse형(3.5％)이 감소한 것 외에는 표준 위치에서 나타난 결과와 유사하였다. 5. 피사체 두부 위치의 변화에 따른 이공의 수평적 위치의 변화는 표준 위치에서 두부를 10mm 전방 이동시킨 위치에서 제1소구치와 제2소구치 사이에 위치한 경우(35.2％)가 감소한 반면 제2소구치와 제1대구치 사이에 위치한 경우(8.8％)는 더 많이 관찰되었으며, 두부를 10mm후방 이동시킨 위치와 피사체의 턱을 10° 상방 이동시킨 위치에서는 제2소구치와 제1대구치 사이에 위치한 경우(6.1％, 7.5％)가 더 많이 관찰되었으며, 피사체의 턱을 10° 하방 이동시킨 위치에서는 표준 위치에서 나타난 결과와 유사하였다. 6. 피사체 두부 위치의 변화에 따른 이공의 수직적 위치 변화는 치근단에 비해 하방에 위치한 경우가 약 90％로 대부분이었으며, 치근단에 접하는 경우, 치근단과 겹쳐 나타난 경우의 순으로 관찰되었으며, 치근단에 비해 상방에 위치하는 경우는 관찰되지 않았다.

• Imaging Science in Dentistry
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• 제33권4호
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• pp.199-205
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• 2003

Purpose: To compare the visibility of the mandibular canal at the different radiographic methods such as conventional panoramic radiographs, Vimplant multi planar reformatting (MPR)-CT panoramic images, Vimplant MPR-CT paraxial images and film-based DentaScan MPR-CT images. Materials and Methods: Data of 11 mandibular dental implant patients, who had been planned treatment utilizing both panoramic and MPR-CT examination with DentaScan software (GE Medical systems, Milwaukee, USA), were used in this study. The archived axial CT data stored on CD-R discs were transferred to a personal computer with 17' LCD monitor. Paraxial and panoramic images were reconstructed using Vimplant software (CyberMed Inc., Seoul, Korea). Conventional panoramic radiographs, monitor-based Vimplant MPR-CT panoramic images, monitor-based Vimplant MPR-CT paraxial images, and film-based DentaScan MPR-CT images were evaluated for visibility of the mandibular canal at the mental foramen, 1 cm, 2 cm, and 3 cm posterior to mental foramen using the 4-point grading score. Results: Vimplant MPR-CT panoramic, paraxial, and DentaScan MPR-CT images revealed significantly clearer images than conventional panoramic radiographs. Particularly at the region 1 em posterior to mental foramen, conventional panoramic radiographs showed a markedly lower percentage of 'excellent' mandibular canal images than images produced by other modalites. Vimplant MPR-CT and DentaScan MPR-CT images did not show significant difference in visibility of the mandibular canal. Conclusion: The study results show that Vimplant and DentaScan MPR-CT imaging systems offer significantly better images of the mandibular canal than conventional panoramic radiograph.

• Restorative Dentistry and Endodontics
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• 제47권1호
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• pp.1.1-1.13
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• 2022

Objectives: This study assessed the shape and anatomical relationship of the mental foramen (MF) to mandibular posterior teeth in an Indian sub-population. Materials and Methods: In total, 475 existing cone-beam computed tomography records exhibiting 950 MFs and including the bilateral presence of mandibular premolars and first molars were assessed. Images were evaluated 3-dimensionally to ascertain the position, shape, and anatomical proximity of MFs to mandibular teeth. The position and shape of MFs were measured and calculated. The Pythagorean theorem was used to calculate the distance between the root apex of the mandibular teeth and the MF. Results: MFs exhibited a predominantly round shape (left: 67% and right: 65%) followed by oval (left: 30% and right: 31%) in both males and females and in different age groups. The root apices of mandibular second premolars (left: 71% and right: 62%) were closest to the MF, followed by distal to the first premolars and mesial to the second premolars. The mean vertical distance between the MF and the nearest tooth apex calculated on sagittal sections was 2.20 mm on the right side and 2.32 mm on the left side; no significant difference was found according to sex or age. The distance between the apices of the teeth and the MF was ≥ 4 mm (left; 4.09 ± 1.27 mm and right; 4.01 ± 1.15 mm). Conclusions: These findings highlight the need for clinicians to be aware of the location of the MF in treatment planning and while performing non-surgical and surgical endodontic procedures.