L. Qu, est le CBCT semble donc indispensable en pré-opératoire dès lors qu'une projection du NAI sur la troisième molaire est visible à la radiographie panoramique

. Si-le-risque-est-avéré-le-praticien-pourra1-]-o, D. Breik, ]. Grubor, E. Catherine, U. Massereau et al., The incidence of mandibular third molar impactions in different skeletal face types L'information du patient pour la chirurgie d'avulsion des dents de sagesse Available: https://www.informationdentaire .fr/produits The radiological prediction of inferior alveolar nerve injury during third molar surgery Does 3-dimensional imaging of the third molar reduce the risk of experiencing inferior alveolar nerve injury owing to extraction?: A meta-analysis Accuracy of cone-beam computed tomography in defining spatial relationships between third molar roots and inferior alveolar nerve, Aust. Dent. J. Br. J. Oral Maxillofac. Surg. J. Am. Dent. Assoc. Eur. J. Dent, vol.53237398, issue.10 4, pp.320-324, 1939.

P. Rouas, J. Nancy, D. Bar, A. E. Borgonovo, F. Rigaldo et al., Identification of double mandibular canals: literature review and three case reports with CT scans and cone beam CT, LEFILDENTAIRE magazine dentaire, pp.34-38, 2007.
DOI : 10.1016/S0096-6347(42)90381-8

N. Bellaiche and P. Radiologue, Place de la technologie Cone Beam en imagerie odontostomatologique, 2009.

]. R. Rodriguez, Y. Baena, R. Beltrami, A. Tagliabo, S. Rizzo et al., Differences between panoramic and Cone Beam-CT in the surgical evaluation of lower third molars, J. Clin. Exp. Dent, vol.9, issue.11 2, pp.259-265, 2017.

]. T. Fortin, Radioprotection??: tomographie ?? faisceau conique pour la chirurgie orale et maxillo-faciale, M??decine Buccale Chirurgie Buccale, vol.45, issue.1, pp.60-77, 2012.
DOI : 10.1016/j.bjoms.2005.06.031

URL : https://www.mbcb-journal.org/articles/mbcb/pdf/2012/01/mbcb120001.pdf

R. Cavézian and G. Pasquet, Imagerie et orthop??die dento-faciale??: ??volution, pr??sent et avenir, l'Orthodontie Fran??aise, vol.64, issue.1, pp.3-12, 2008.
DOI : 10.1051/orthodfr:2007043

Y. S. Cordoliani, P. Grenier, H. Beauvais, J. Grellet, E. Marshall-depommier et al., Le point sur les procedures en radiologie conventionnelle et en tomodensitometrie Tomographie volumique à faisceau conique de la face (cone beam computerized tomography) Patient risk related to common dental radiographic examinations: the impact of 2007 International Commission on Radiological Protection recommendations regarding dose calculation, Med Nucl Imag Fonct Metab, pp.241-246, 1939.

J. B. Ludlow, L. E. Davies-ludlow, S. L. Brooks, and W. B. Howerton, Dosimetry of 3 CBCT devices for oral and maxillofacial radiology: CB Mercuray, NewTom 3G and i-CAT, Dentomaxillofacial Radiology, vol.35, issue.4, pp.219-226, 2006.
DOI : 10.1016/S1079-2104(96)80448-3

]. T. Okano, Absorbed and effective doses from cone beam volumetric imaging for implant planning Effective dosages for recording Veraviewepocs dental panoramic images: analog film, digital, and panoramic scout for CBCT, Dento Maxillo Facial Radiol. Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod, vol.38, issue.106 4, pp.79-85, 2008.

J. M. Palomo, P. S. Rao, and M. G. Hans, Influence of CBCT exposure conditions on radiation dose, Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, vol.105, issue.6, pp.773-782, 2008.
DOI : 10.1016/j.tripleo.2007.12.019

M. A. Silva, U. Wolf, F. Heinicke, A. Bumann, H. Visser et al., Cone-beam computed tomography for routine orthodontic treatment planning: A radiation dose evaluation, American Journal of Orthodontics and Dentofacial Orthopedics, vol.133, issue.5, pp.640-641, 2008.
DOI : 10.1016/j.ajodo.2007.11.019

J. B. Ludlow, L. E. Davies-ludlow, and S. L. Brooks, Dosimetry of two extraoral direct digital imaging devices: NewTom cone beam CT and Orthophos Plus DS panoramic unit, Dentomaxillofacial Radiology, vol.32, issue.4, pp.229-234, 2003.
DOI : 10.1067/moe.2001.113591

J. B. Ludlow and M. Ivanovic, Comparative dosimetry of dental CBCT devices and 64-slice CT for oral and maxillofacial radiology, Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, vol.106, issue.1, pp.106-114, 2008.
DOI : 10.1016/j.tripleo.2008.03.018

S. Lofthag-hansen, A. Thilander-klang, A. Ekestubbe, E. Helmrot, and K. Gröndahl, Calculating effective dose on a cone beam computed tomography device: 3D Accuitomo and 3D Accuitomo FPD, Dentomaxillofacial Radiology, vol.37, issue.2, pp.72-79, 2008.
DOI : 10.1118/1.2173933

]. E. Hirsch, U. Wolf, F. Heinicke, and M. A. Silva, Dosimetry of the cone beam computed tomography Veraviewepocs 3D compared with the 3D Accuitomo in different fields of view, Dentomaxillofacial Radiology, vol.37, issue.5, pp.268-273, 2008.
DOI : 10.1067/moe.2000.109189

M. Loubele, R. Bogaerts, E. Van-dijck, R. Pauwels, S. Vanheusden et al., Comparison between effective radiation dose of CBCT and MSCT scanners for dentomaxillofacial applications Effective dose from cone beam CT examinations in dentistry Dosimetry and image quality of four dental cone beam computed tomography scanners compared with multislice computed tomography scanners, Eur. J. Radiol. Br. J. Radiol. Dentomaxillofacial Radiol, vol.71, issue.38 6, pp.461-468, 2009.

X. Qu, G. Li, J. B. Ludlow, Z. Zhang, and X. Ma, Effective radiation dose of ProMax 3D cone-beam computerized tomography scanner with different dental protocols, Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, vol.110, issue.6, pp.770-776, 2010.
DOI : 10.1016/j.tripleo.2010.06.013

R. Pauwels, J. Beinsberger, B. Collaert, C. Theodorakou, J. Rogers et al., Effective dose range for dental cone beam computed tomography scanners, European Journal of Radiology, vol.81, issue.2, pp.267-271, 2012.
DOI : 10.1016/j.ejrad.2010.11.028

K. Tsiklakis, C. Donta, S. Gavala, K. Karayianni, V. Kamenopoulou et al., Dose reduction in maxillofacial imaging using low dose Cone Beam CT, European Journal of Radiology, vol.56, issue.3, pp.413-417, 2005.
DOI : 10.1016/j.ejrad.2005.05.011

]. N. Faccioli, M. Barillari, S. Guariglia, E. Zivelonghi, A. Rizzotti et al., Riduzione di dose radiante mediante utilizzo della TC a fascio conico nei pazienti ipoacusici, La radiologia medica, vol.117, issue.8, pp.1308-1318, 2009.
DOI : 10.1259/bjr.74.878.740153

M. Loubele, R. Jacobs, F. Maes, F. Schutyser, D. Debaveye et al., Radiation dose vs. image quality for low-dose CT protocols of the head for maxillofacial surgery and oral implant planning, Radiation Protection Dosimetry, vol.117, issue.1-3, pp.1-3, 2005.
DOI : 10.1007/3-540-45468-3_118

P. Hubert, Exposition de la population française à l'irradiation naturelle, Actes de la 4e Conférence Acomen, pp.6-7, 1993.

K. Horner, M. Islam, L. Flygare, K. Tsiklakis, and E. Whaites, Basic principles for use of dental cone beam computed tomography: consensus guidelines of the European Academy of Dental and Maxillofacial Radiology, Dentomaxillofacial Radiology, vol.38, issue.4, pp.187-195, 2009.
DOI : 10.1111/j.1540-5915.1997.tb01330.x

]. A. Haroun, Recommandations de l'HAS sur l'avulsion des troisièmes molairesUnion Natl. Pour L'Intérêt L'Orthopédie Dento-Faciale Characterization of third molar morphometric variables, Acta Odontol. Latinoam. AOL, vol.29, issue.37 2, pp.22-37, 2008.

T. Hasegawa, Risk factors associated with inferior alveolar nerve injury after extraction of the mandibular third molar???a comparative study of preoperative images by panoramic radiography and computed tomography, International Journal of Oral and Maxillofacial Surgery, vol.42, issue.7, pp.843-851, 2013.
DOI : 10.1016/j.ijom.2013.01.023

]. W. Tantanapornkul, D. Mavin, J. Prapaiphittayakun, N. Phipatboonyarat, and W. Julphantong, Accuracy of Panoramic Radiograph in Assessment of the Relationship Between Mandibular Canal and Impacted Third Molars, The Open Dentistry Journal, vol.10, issue.1, pp.322-329, 2016.
DOI : 10.2174/1874210601610010322

G. Xu, C. Yang, X. Fan, C. Yu, X. Cai et al., Anatomic relationship between impacted third mandibular molar and the mandibular canal as the risk factor of inferior alveolar nerve injury, British Journal of Oral and Maxillofacial Surgery, vol.51, issue.8, pp.215-219, 2013.
DOI : 10.1016/j.bjoms.2013.01.011

H. Ghaeminia, G. J. Meijer, A. Soehardi, W. A. Borstlap, J. Mulder et al., Position of the impacted third molar in relation to the mandibular canal. Diagnostic accuracy of cone beam computed tomography compared with panoramic radiography, International Journal of Oral and Maxillofacial Surgery, vol.38, issue.9, pp.964-971, 2009.
DOI : 10.1016/j.ijom.2009.06.007

Y. T. Korkmaz, S. Kay?pmaz, F. C. Senel, K. T. Atasoy, and Z. Gumrukcu, Does additional cone beam computed tomography decrease the risk of inferior alveolar nerve injury in high-risk cases undergoing third molar surgery?Does CBCT decrease the risk of IAN injury?, International Journal of Oral and Maxillofacial Surgery, vol.46, issue.5, pp.628-635, 2017.
DOI : 10.1016/j.ijom.2017.01.001

-. Habert-lucie, Troisièmes molaires mandibulaires : Evaluation prospective des pratiques professionnelles lors de la prescription de Cone Beam Computed Tomography (CBCT)

C. Odontologie-du and . La-timone-À-marseille, Elle avait pour but l'évaluation des pratiques professionnelles lors de la prescription de CBCT pour l'examen des 3M avant avulsion, ainsi qu'une comparaison des rapports anatomiques observés sur l'orthopantomogramme (OPT) et sur le CBCT de ces mêmes cas. L'étude a inclus 39 patients correspondant à 56 3M Tous les CBCT étaient prescrits car il existait un rapport anatomique étroit entre NAI et 3M sur l'OPT : contact dans 28% des prescriptions et projection dans 72%. Lorsqu'il y avait présence d'un contact2% de ces cas présentaient un contact également sur le CBCT, dont seulement 33,3% d'entre eux avaient un NAI pincé. Lorsqu'il y avait présence d'une projection, 8% des cas présentaient un contact sur le CBCT dont 712% qui ne présentaient pas de contact sur le CBCT, la totalité de ces cas présentait un NAI en situation vestibulaire et non pincé

C. Le, . Donc-indispensable-dès-lors, and . Qu, il y a une projection du NAI et de la 3M sur l'OPT. Concernant la radioprotection l'ensemble de ces examens semblent justifiés, cependant lors d'un contact, sa prescription ne semble pas impérative