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Mandibular Canal (mandibular + canal)
Selected AbstractsA Comparative Study of Computed Tomography and Magnetic Resonance Imaging for the Detection of Mandibular Canals and Cross-Sectional Areas in Diagnosis prior to Dental Implant TreatmentCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2004Hideyuki Imamura DDS ABSTRACT Background: Computed tomography (CT) is effective in the diagnosis of dental implants. However, it has the disadvantage of exposing patients to high doses of x-rays, and the mandibular canals cannot be detected by CT in some clinical cases. Purpose: The purpose of this study was to examine the detectability of the anatomic morphology of the molar region in the lower jaw (where implantation is common) by CT and magnetic resonance imaging (MRI), to compare the data, and to determine the usefulness of MRI in diagnosis prior to dental implant treatments. Materials and Methods: Eleven female subjects (average age, 59 years) who had partially edentulous mandibles (total of 19 sites) were included in the study. CT and MRI were performed with the same subjects, and the degrees of identification of the mandibular canal in the first and second molar regions were compared. Dimensional accuracy in the second molar region was also compared. Results: With CT, the canals of the first molar regions were not identified in 11 of 19 sites; however, MRI identified the canals in all 19 sites. Using the kappa index, we found that the inter- and intraobserver identification reliabilities (0.84 and 0.87, respectively) were excellent, especially for MRI. Dimensional positioning of the canal in the second molar region was almost the same with MRI as with CT. Conclusions: MRI is an alternative method in diagnosis prior to dental implant treatment in the mandibular molar region. [source] Continuing education self-assessment quiz: Failure to obtain adequate anaesthesia associated with a bifid mandibular canal: a case reportAUSTRALIAN DENTAL JOURNAL, Issue 1 2006Article first published online: 12 MAR 200 In the case report by Lew and Townsend on page 86 of this issue several important issues are raised about the administration of mandibular anaesthesia in dental practice. Test your knowledge here by first reading the article entitled: Failure to obtain adequate anaesthesia associated with a bifid mandibular canal: a case report, answer the following questions and then forward the completed questionnaire to the Australian Dental Journal Office and we will let you know how you scored. Please place a tick in the box alongside the option that you think provides the best answer to each question, i.e., one tick per question. The Editor's decision is final and no correspondence will be entered into. [source] A Comparative Study of Computed Tomography and Magnetic Resonance Imaging for the Detection of Mandibular Canals and Cross-Sectional Areas in Diagnosis prior to Dental Implant TreatmentCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2004Hideyuki Imamura DDS ABSTRACT Background: Computed tomography (CT) is effective in the diagnosis of dental implants. However, it has the disadvantage of exposing patients to high doses of x-rays, and the mandibular canals cannot be detected by CT in some clinical cases. Purpose: The purpose of this study was to examine the detectability of the anatomic morphology of the molar region in the lower jaw (where implantation is common) by CT and magnetic resonance imaging (MRI), to compare the data, and to determine the usefulness of MRI in diagnosis prior to dental implant treatments. Materials and Methods: Eleven female subjects (average age, 59 years) who had partially edentulous mandibles (total of 19 sites) were included in the study. CT and MRI were performed with the same subjects, and the degrees of identification of the mandibular canal in the first and second molar regions were compared. Dimensional accuracy in the second molar region was also compared. Results: With CT, the canals of the first molar regions were not identified in 11 of 19 sites; however, MRI identified the canals in all 19 sites. Using the kappa index, we found that the inter- and intraobserver identification reliabilities (0.84 and 0.87, respectively) were excellent, especially for MRI. Dimensional positioning of the canal in the second molar region was almost the same with MRI as with CT. Conclusions: MRI is an alternative method in diagnosis prior to dental implant treatment in the mandibular molar region. [source] Vertical ridge augmentation of the atrophic posterior mandible with interpositional bloc grafts: bone from the iliac crest vs. bovine anorganic bone.CLINICAL ORAL IMPLANTS RESEARCH, Issue 12 2009Clinical, histological results up to one year after loading from a randomized-controlled clinical trial Abstract Objectives: To compare two different techniques for vertical bone augmentation of the posterior mandible: bone blocs from the iliac crest vs. anorganic bovine bone blocs used as inlays. Materials and methods: Ten partially edentulous patients having 5,7 mm of residual crestal height above the mandibular canal had their posterior mandibles randomly allocated to both interventions. After 4 months implants were inserted, and after 4 months, provisional prostheses were placed. Definitive prostheses were delivered after 4 months. Histomorphometry of samples trephined at implant placement, prosthesis and implant failures, any complication after loading and peri-implant marginal bone-level changes were assessed by masked assessors. All patients were followed up to 1 year after loading. Results: Four months after bone augmentation, there was statistically significant more residual graft (between 10% and 13%) in the Bio-Oss group. There were no statistically significant differences in failures and complications. Two implants could not be placed in one patient augmented with autogenous bone because the graft failed whereas one implant and its prosthesis of the Bio-Oss group failed after loading. After implant loading only one complication (peri-implantitis) occurred at one implant of the autogenous bone group. In 16 months (from implant placement to 1 year after loading), both groups lost statistically significant amounts of peri-implant marginal bone: 0.82 mm in the autogenous bone group and 0.59 mm in the Bio-Oss group; however, there were no statistically significant differences between the groups. Conclusions: Both procedures achieved good results, but the use of bovine blocs was less invasive and may be preferable than harvesting bone from the iliac crest. [source] CAD/CAM fabrication and clinical application of surgical template and bone model in oral implant surgeryCLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2009Taiji Sohmura Abstract Objectives: A novel implant surgery support system with computer simulation for implant insertion and fabrication of a surgical template that helps in drilling bone was developed. A virtual reality haptic device that gives the sense of touch was used for simulation and a surgical template was fabricated by CAD/CAM method. Surgical guides were applied for two clinical cases. Material and methods: Three-dimensional (3D) jaw bone images transferred from DICOM data filmed by CT scanner were fed to the software and manipulated using the haptic device. The site for implant insertion was determined after evaluating the quality of bone and position of the mandibular canal. The surgical template was designed with ease using the free design CAD function of haptic device. The surgical template and bone model were fabricated by a fused deposit modeling machine. Two clinical cases were applied using the present system. Results: Simulation to determine the site of implant insertion and fabrication of the surgical bone templates were successfully done in two clinical cases, one for three implant insertion in lower right jaw and the other is for seven implant insertion in lower edentulous jaw, respectively. During surgery, the templates could be firmly adapted on the bone and drilling was successfully performed in both cases. Conclusion: The present simulation and drilling support using the surgical template may help to perform safe and accurate implant surgery. [source] Radiologic measurements of the mandible: a comparison between CT-reformatted and conventional tomographic imagesCLINICAL ORAL IMPLANTS RESEARCH, Issue 2 2004Hanazawa Tomomi Abstract: This study was carried out to compare the accuracy of determination of the mandibular contour and the position of the mandibular canal in cadaver mandibles by the multiplanar reconstruction method (MPR-CT), which has recently come to be used widely for preoperative examinations, with those by tomographic techniques and to evaluate the usefulness of MPR-CT. Using three imaging systems, i.e. Quantum CT scanner, Scanora, and OP-100, a total of 6 sites were scanned in the molar regions of 3 cadaver mandibles. The images obtained were measured twice each by 4 radiologists. The anatomic structures measured were the height and thickness of the mandible, distance from the alveolar crest to the mandibular canal, and distance from the buccal cortical bone to the mandibular canal. After scanning, the scanned areas of the mandibles were sliced at a thickness of 2 mm, and soft X-ray images of these slices were obtained. The values of the above 4 anatomic structures obtained by measurements in the soft X-ray radiograms using digital-display calipers were regarded as true values. When compared with the true values, the errors in the distance from the alveolar crest to the mandibular canal were within 1 mm (±1 mm) in 93.7% of the measurements by Direct-CT, 89.6% of the measurements by MPR-CT, 87.5% of the measurements by Scanora, and 47.9% of the measurements by OP-100, and the accuracy of the 4 methods ranked in the order of Direct-CT, MPR-CT, Scanora, and OP-100. A similar tendency was observed in the measurements of other anatomic structures, and statistically significant differences were observed among the methods. Thus, MPR-CT allows more accurate measurements than by the other 2 tomographic techniques,and to be useful as a preoperative examination for implant surgery. Résumé Cette étude a été menée afin de comparer la précision de la détermination du contour de la mandibule et de la position du canal mandibulaire dans des mandiblules de cadavres par la méthode de reconstruction par multi-plans (MPR-CT), qui a récemment été très utilisée pour les examens préopératoires, avec celle des techniques de tomographie et d'évaluer l'utilité de MPR-CT en utilisant trois systèmes d'image; c.-à-d. le scanner CT Quantum, le Scanora et l'OP-100, Six sites ont été balayés dans la région molaire de trois mandibules de cadavres. Les images obtenues ont été mesurées deux fois par quatre radiologues. Les structures anatomiques mesurées étaient la hauteur et l'épaisseur de la mandibule, la distance du rebord alvéolaire jusqu'au canal mandibulaire et la distance de l'os cortical vestibulaire au canal mandibulaire. Après balayage, les zones balayées des mandibules ont été coupées en tranches d'une épaisseur de 2 mm et des images radiographiques de ces tranches ont été obtenues. Les valeurs des quatre structures anatomiques mentionnées précédemment obtenues par les mesures des radiogrammes utilisant les compas digitaux étaient considérées comme valeurs correctes. Lorsqu'elles étaient comparées aux valeurs correctes, les erreurs dans la distance du rebord alvéolaire jusqu'au canal mandibulaire étaient inférieures à 1±1 mm dans 94 % des mesures par CT-Direct, 90% dans les mesures par MPR-CT, 88% des mesures par Scanora et 48% des mesures par OP-100, et la précision des quatre méthodes était dans l'ordre CT-Direct, MPR-CT, Scanora et OP-100. Une tendance semblable a été observée dans les mesures d'autres structures anatomiques et des différences statistiquement significatives ont été observées parmi les méthodes. Le CT-PMR apporte donc plus de mesures précises que les deux autres techniques de tomographie et devrait être utilisé pourl'examen préopératoire lors de la chirurgie implantaire. Zusammenfassung Radiologische Messungen im Unterkiefer: Ein Vergleich zwischen reformatierten CTs und konventionellen tomographischen Bildern Diese Studie wurde durchgeführt, um die Genauigkeit bei der Bestimmung der Kontur des Unterkiefers und bei der Lokalisation des Mandibularkanals in Kadaverunterkiefern durch die multiplanare Rekonstruktionsmethode (MPR-CT) mit konventionellen tomographischen Techniken zu vergleichen. Die MPR-CT wird seit kurzem oft für präoperative Untersuchungen angewendet. Zudem sollte die Anwendbarkeit der MPR-CT untersucht werden. Bei 3 Kadaverunterkiefern wurden je 6 Stellen in der Molarenregion mit 3 verschiedenen Systemen, Quantum CT Scanner, Scanora und OP-100, untersucht. Die erhaltenen Bilder wurden zweimal durch 4 Radiologen ausgewertet. Die folgenden anatomischen Strukturen wurden ausgemessen: Höhe und Dicke des Unterkiefers, Distanz vom Alveolarkamm zum Mandibularkanal und Distanz vom bukkalen kortikalen Knochen zum Mandibularkanal. Nach den Aufnahmen wurden die untersuchten Stellen auf eine Dicke von 2 mm geschnitten und es wurden Röntgenaufnahmen mit weichen Strahlen von den Schnitten angefertigt. Die Werte der obenerwähnten 4 anatomischen Strukturen, welche durch Messungen in den Röntgen mit weicher Strahlung mittels Zirkel mit Digitalanzeige ermittelt worden waren, wurden als wahre Werte angenommen. Im Vergleich zu den wahren Werten lag der Fehler bei der Distanz vom Alveolarkamm zum Mandibularkanal bei 93.7% der Messungen mit direktem CT, bei 89.6% der Messungen mit MPR-CT, bei 87.5% der Messungen mit Scanora und bei 47.9% der Messungen mit dem OP-100 innerhalb von 1mm (±1mm). Die Genauigkeit der 4 Methoden nahm in folgender Reihenfolge ab: direkte CT, MPR-CT, Scanora und OP-100. Eine ähnliche Tendenz konnte bei den Messungen der anderen anatomischen Strukturen beobachtet werden und zwischen den Methoden bestanden statistisch signifikante Unterschiede. Die MPR-CT ergaben genauere Messungen als die zwei anderen tomographischen Techniken. Die Methode ist daher hilfreich bei der präoperativen Untersuchung vor Implantatchirurgie. Resumen Este estudio se llevó a cabo para comparar la exactitud de la determinación del contorno mandibular y la posición del canal mandibular en mandíbulas de cadáver por medio del método de reconstrucción multiplanar (MPR-CT), que recientemente se ha convertido de uso extendido para exámenes preoperatorios, con aquellas técnicas tomográficas y para evaluar la utilidad de MPR-CT. Se escanearon un total de 6 lugares en la región molar de 3 mandíbulas de cadáver usando tres sistemas de imágenes, i.e. escáner Quantum CT, Scanora y OP-100. Las imágenes obtenidas se midieron dos veces cada una por 4 radiólogos. Las estructuras anatómicas medidas fueron altura y grosor de la mandíbula, distancia de la cresta alveolar al canal mandibular, y distancia desde el hueso cortical vestibular al canal mandibular. Tras realizar el escáner, las áreas escaneadas de las mandíbulas se cortaron en lonchas de 2 mm de grosor, y se obtuvieron imágenes radiológicas blandas de estos cortes. Los valores de las ya mencionadas 4 estructuras anatómicas obtenidas por mediciones en los radiogramas radiográficos usando calibres de visualización digital se consideraron como valores reales, los errores en la distancia desde la cresta alveolar al canal mandibular estaban dentro de 1 mm (±1 mm) en 93.7% de las mediciones por CT-directa, 89.6% de las mediciones por MPR_CT, 87.5% de las mediciones por Scanora, y el 47.9% de las mediciones por OP-100, y la exactitud de los 4 métodos se clasificaron en orden de CT-directa, MPR-CT, MPR-CT, Scanora, y OP-100. Se observó una tendencia similar en las mediciones de otras estructuras anatómicas, y se observaron diferencias estadísticamente significativas entre los métodos. De este modo, MPR-CT permite unas mediciones mas exactas que las de las otras 2 técnicas tomográficas, y ser útil como examen preoperatorio para cirugía de implantes. [source] A Comparative Study of Computed Tomography and Magnetic Resonance Imaging for the Detection of Mandibular Canals and Cross-Sectional Areas in Diagnosis prior to Dental Implant TreatmentCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2004Hideyuki Imamura DDS ABSTRACT Background: Computed tomography (CT) is effective in the diagnosis of dental implants. However, it has the disadvantage of exposing patients to high doses of x-rays, and the mandibular canals cannot be detected by CT in some clinical cases. Purpose: The purpose of this study was to examine the detectability of the anatomic morphology of the molar region in the lower jaw (where implantation is common) by CT and magnetic resonance imaging (MRI), to compare the data, and to determine the usefulness of MRI in diagnosis prior to dental implant treatments. Materials and Methods: Eleven female subjects (average age, 59 years) who had partially edentulous mandibles (total of 19 sites) were included in the study. CT and MRI were performed with the same subjects, and the degrees of identification of the mandibular canal in the first and second molar regions were compared. Dimensional accuracy in the second molar region was also compared. Results: With CT, the canals of the first molar regions were not identified in 11 of 19 sites; however, MRI identified the canals in all 19 sites. Using the kappa index, we found that the inter- and intraobserver identification reliabilities (0.84 and 0.87, respectively) were excellent, especially for MRI. Dimensional positioning of the canal in the second molar region was almost the same with MRI as with CT. Conclusions: MRI is an alternative method in diagnosis prior to dental implant treatment in the mandibular molar region. [source] | ||||||||||