Relationship of the Presence of Lingual Concavity and Mandibular Canal Location: A Retrospective Two-Center Study

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.

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Positive Predictive Value of Panoramic Radiography for Assessment of the Relationship of Impacted Mandibular Third Molars with the Mandibular Canal Based on Cone-Beam Computed Tomography: A Cross-Sectional Study

Diagnostics ◽

10.3390/diagnostics11091578 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1578

Author(s):

Maryam Tofangchiha ◽

Soheil Koushaei ◽

Maryam Mortazavi ◽

Zahra Souri ◽

Ahad Alizadeh ◽

...

Keyword(s):

Root Apex ◽

Mandibular Canal ◽

Cross Sectional Study ◽

White Line ◽

Cross Sectional ◽

Panoramic Radiographs ◽

Impacted Mandibular Third Molars ◽

Mandibular Third Molars ◽

Relationship Of ◽

The Relationship

The aim of the present study was to assess the positive predictive value (PPV) of panoramic radiographic signs in the assessment of the relationship between impacted mandibular third molars (IMTMs) and the mandibular canal (MC). This cross-sectional study was conducted by reviewing 102 cone-beam computed tomography (CBCT) and panoramic radiographs of patients with IMTMs and radiographic signs of the contact of the IMTMs with the MC on panoramic radiographs (i.e., root apex darkening and interference with the white line). A positive relationship of the IMTM roots with the MC based on CBCT findings was recorded as the gold standard. The PPV of panoramic radiographic signs was calculated for the detection of the relationship of the IMTM root with the MC. The IMTMs were in contact with the MC on CBCT scans in 90.1% of the cases. The PPV of root apex darkening and the interference with the white line was found to be 89.09% (95% CI: (77.75, 95.88)) and 91.48% (95% CI: (79.62, 97.63)), respectively. The MC had a buccal position in 63.7%, and a lingual position in 35.2%, of the cases. The contact of IMTMs with the MC was more commonly seen in patients with a lingual position (100% of the samples). The IMTM root apex darkening and interference with the white line of the MC on panoramic radiographs had a high PPV for determination of the contact of IMTMs with the MC. Thus, presence of the above-mentioned risk factors indicates the need for subsequent 3D radiographic assessments.

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Questionnaire survey on methods of determining the relationship of the mandibular canal and third molars

Journal of BP Koirala Institute of Health Sciences ◽

10.3126/jbpkihs.v1i1.19753 ◽

2018 ◽

Vol 1 (1) ◽

pp. 44-50

Author(s):

Apeksha Mainali ◽

A Vaidya

Keyword(s):

Computed Tomography ◽

Cone Beam Computed Tomography ◽

Three Dimensional ◽

Panoramic Radiograph ◽

Mandibular Canal ◽

Cone Beam ◽

Third Molars ◽

Dental Practitioners ◽

Relationship Of ◽

The Relationship

Background: Clinicians should assess and monitor mandibular canal (MC) to achieve an uneventful and successful final result. Two dimensional techniques like panoramic radiography, intra oral periapical radiographs are commonly used for assessment of MC, along with three dimensional techniques like cone beam computed tomography (CBCT).Objectives: To assess the radiologic modalities and assessment criteria used by clinically practicing dental surgeons when determining the proximity of MC to third molars.Method: A questionnaire based study was carried out among national and international oral maxillofacial surgeons and general dental practitioners. Data were fed to SPSS software version 21 for descriptive statistics.Result: Most of the participants (54.7%) in the study preferred combination of panoramic radiograph and CBCT for determining the relationship of mandibular canal and third molars measures.Conclusion: Initial screening can be carried out using panoramic radiograph which is a popular method in determining the relation between the third molar and mandibular canal in spite of some limitations. Cone Beam Computed Tomography is an important three-dimensional imaging technique which is a preferred method amongst most dental surgeons.Journal of BP Koirala Institute of Health Sciences, Vol. 1, No. 1, 2018, page: 44-50

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