Comparison of 3 deep learning neural networks for classifying the relationship between the mandibular third molar and the mandibular canal on panoramic radiographs

2020 ◽  
Vol 130 (3) ◽  
pp. 336-343 ◽  
Author(s):  
Motoki Fukuda ◽  
Yoshiko Ariji ◽  
Yoshitaka Kise ◽  
Michihito Nozawa ◽  
Chiaki Kuwada ◽  
...  
2014 ◽  
Vol 15 (6) ◽  
pp. 740-745
Author(s):  
Mojdeh Mehdizadeh ◽  
Navid Ahmadi ◽  
Mahsa Jamshidi

ABSTRACT Objectives Exact location of the inferior alveolar nerve (IAN) bundle is very important. The aim of this study is to evaluate the relationship between the mandibular third molar and the mandibular canal by cone-beam computed tomography. Study design This was a cross-sectional study with convenience sampling. 94 mandibular CBCTs performed with CSANEX 3D machine (Soredex, Finland) and 3D system chosen. Vertical and horizontal relationship between the mandibular canal and the third molar depicted by 3D, panoramic reformat view of CBCT and cross-sectional view. Cross-sectional view was our gold standard and other view evaluated by it. Results There were significant differences between the vertical and horizontal relation of nerve and tooth in all views (p < 0.001). Conclusion The results showed differences in the position of the inferior alveolar nerve with different views of CBCT, so CBCT images are not quite reliable and have possibility of error. How to cite this article Mehdizadeh M, Ahmadi N, Jamshidi M. Evaluation of the Relationship between Mandibular Third Molar and Mandibular Canal by Different Algorithms of Cone-beam Computed Tomography. J Contemp Dent Pract 2014;15(6):740-745.


Author(s):  
Büyük Kaan Orhan ◽  
Dilek Yılmaz ◽  
Mehmet Ozgur Ozemre ◽  
Kıvanç Kamburoğlu ◽  
Orhan Gulen ◽  
...  

Objectives: To evaluate impacted mandibular third molar tooth region and obtain linear measurements using CBCT images and to assess the relationship between the impacted third molar and the mandibular canal. Methods: CBCT scans of 351 patients (208 females, 143 males) were assessed. Age, gender, and impaction site were recorded for each patient. The relationship of third molars with the vertical axis of second molars, 2nd molar resorption and the relationship between third molar apices and the mandibular canal were assessed. In addition, the distance between ramus and second molar, mesiodistal width of the third molar, the angle between third molar and second molar, and width of the third molar capsule were measured. Binary Logistic Regression, Chi-Square Test, and General Linear Model were used for statistical analysis. Results: The highest percentage of impaction was found for mesioangular followed by transversal and vertical. The transversal impacted third molars revealed a significant association with adjacent second molar root resorption (p<0.001). There was a statistical significance between the second molar resorption and distance between ramus and second molar (p<0.001). The mesioangular impacted third molars revealed significant relation with the mandibular canal (p<0.05). The most frequent variation found was the dental canal followed by the retromolar canal. In general, higher measurement values were obtained for men when compared to women (p<0.05). Conclusion: CBCT assessment of the third molar region provided useful information regarding impacted mandibular third molar surgery operations.


2012 ◽  
Vol 13 (6) ◽  
pp. 819-823 ◽  
Author(s):  
Uma Shankar ◽  
KR Hari ◽  
T Praveen Kumar Reddy ◽  
Shravan Kumar Katakam ◽  
Deepti Janga

ABSTRACT Background Permanent mandibular third molar are most commonly impacted teeth. In planning the surgical removal of mandibular third molar, correct diagnosis requires not only their precise spatial location, but also a thorough and accurate assessment of the intimate relationship with adjacent anatomical structures. Various imaging modalities have been used for localizing the mandibular third molar but not satisfactorily. Aim This prospective study of 30 patients with 42 impacted mandibular third molars was carried out with the aim of finding evidence for justifying the use of computed tomography and orthopantomography as a diagnostic modality, prior to surgical intervention of impacted mandibular third molar. Materials and methods Subjective evaluation of the CT and OPG images by two observed had shown that there was significant difference between the CT and OPG for radiographic visibility of mandibular canal in relation to third molar. Results Data analysis was done with Chi-square test (χ2) and z-test to find the significant difference between the two radiographic modalities OPG and CT in localizing special relationship of impacted mandibular third molar. The comparison of OPG and CT showed z-value >1.5 in darkening of roots (1.98), deflection of root (2.00) interruption of z-value = 0 in narrowing of canal and dark, bifid apexes. Also it showed p-value <0.05 in all the radiographic signs except narrowing of mandibular canal and and dark and bifid apexes. Conclusion The spiral CT image provides a unique opportunity to determine the exact position of impacted mandibular third molar and their relationship to adjacent structure in all three planes. Clinical significance Computed tomography is highly instrumental in depicting the relationship of mandibular third molar with inferior alveolar nerve canal before treatment and accurate appraisal of the several aspects can be made regarding prognosis. How to cite this article Katakam SK, Shankar U, Thakur D, Reddy TPK, Hari KR, Janga D. Comparison of Orthopantomography and Computed Tomography Image for Assessing the Relationship between Impacted Mandibular Third Molar and Mandibular Canal. J Contemp Dent Pract 2012;13(6):819-823.


2013 ◽  
Vol 07 (02) ◽  
pp. 212-217 ◽  
Author(s):  
Suresh Yadav ◽  
Shallu Tyagi ◽  
Naveen Puri ◽  
Prince Kumar ◽  
Puneet Kumar

ABSTRACT Objective: To assess the relationship between impacted mandibular third molar presence and the risk for mandibular angle fracture with the effect of various positions of mandibular third molar and the risk of mandibular angle fracture. Materials and Methods: In the North Indian territory, a total of 289 patients with mandibular angle fractures were studied and evaluated for the possible relationship with impacted third molar on the basis of clinical and panoramic radiographical findings. Results: Results that confirmed the highest risk for mandibular angle fracture was associated with mesioangular angulations (45.42%) followed by vertical (26.34%), distoangular in sequence and least risk was found with bucco-version angulations (2.67%) according to Winter′s classification. Additionally, the highest risk of mandibular angle fracture was reported with partially erupted third molar (47.75%), followed by erupted (23.53%) and unerupted third molar (19.38%). Conclusion: The risk for mandibular angle fracture is not only affected by status of eruption, angulations, position, number of roots present in third molar but also by the distance of mandibular third molar from inferior border of mandible and the percentage of remaining amount of bone at the mandibular angle region.


2000 ◽  
Vol 46 (5) ◽  
pp. 251-261 ◽  
Author(s):  
Toshinori TANAKA ◽  
Kei MURAKAMI ◽  
Tsuyoshi KISHIDA ◽  
Takatoshi ITOH ◽  
Yasuhiko MORITA ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document