Analysis of Genial Tubercle Anatomy Using Cone Beam Computed Tomography – A Retrospective Study from Chennai, India

BACKGROUND Analysis of genial tubercle anatomy using three-dimensional (3D) imaging can be valuable in preparation for genioglossus advancement in the treatment of obstructive sleep apnoea, estimation of the safe zone prior to implant surgery and evaluation of mandibular asymmetry. Hence the intention of the study was to analyse the morphological pattern, dimensions of genial tubercles and their position in the mandible using cone beam computed tomography (CBCT). METHODS A retrospective study was conducted on 100 patients scanned using Sirona Orthophos XG device in the Radiology department, Saveetha dental college and hospital. The genial tubercles were identified, morphological pattern of the genial tubercles was classified into four patterns and linear measurements of the genial tubercle height, width, position of genial tubercles on the mandible in the images were done. The collected data was tabulated and analysed using SPSS software. A paired t - test was used for intra examiner calibration and a chi-square test was used for comparison between genial tubercle patterns in both the sex. RESULTS On analysing the genial tubercle patterns, type I (44) was the most commonly seen followed by type II (24). Genial tubercles were not evident (type IV) in 20 patients. Type III (12) was least commonly seen among the pattern types. CONCLUSIONS The anatomy of genial tubercles is highly variable. The mean height of genial tubercles (GTH) measured was 5.36 mm and mean width of genial tubercles (GTW) measured was 5.24 mm. KEY WORDS Genial Tubercles, Anatomy, Cone Beam Computed Tomography, Mandible

Transoral Approach to Open Reduction of a Traumatic Avulsion Fracture of the Genial Tubercle Associated With a Mandibular Symphysis Fracture: A Case Report and Literature Review

Genial tubercle fracture (GTF) is rare and represents a diagnostic challenge as plain film radiography often fails to identify the fractured segment. Traumatic avulsion of the genial tubercle in conjunction with mandibular symphysis fracture may lead to posterior displacement of the tongue with the potential for airway compromise and difficulty in speech and swallowing due to loss of tongue anterior suspension. Fine cut computed tomography (CT) scan is required to confirm the diagnosis and assist further management. To our knowledge, all published cases of surgical intervention in the management of avulsed genial tubercle combined with fracture of the mandibular symphysis used an extraoral approach via submental skin incision to expose the fractured segment. To the authors’ knowledge, this is the first report to describe a transoral approach in the surgical management of GTF associated with a mandibular fracture.

Genial tubercle position and genioglossus advancement in obstructive sleep apnea (OSA) treatment: a systematic review

Background To systematically review the literature for methods to localize the genial tubercle as a means for performing an advancement of the genioglossus muscle. Methods PubMed, Google Scholar, CRISP, EMBASE, CINAHL, and Scopus were searched from inception through June 16, 2015. Results One hundred fifty-two articles were screened, and the full text versions of 12 articles were reviewed in their entirety and 7 publications reporting their methodology for localizing the genial tubercle. Based upon these measurements and the results published from radiographic imaging and cadaveric dissections of all the papers included in this study, we identified the genial tubercle as being positioned within the mandible at a point 10 mm from the incisor apex and 10 mm from the lower mandibular border. Conclusion Based upon the results of this review, the genial tubercles were positioned within the mandible at a point 10 mm from the incisor apex and 10 mm from the lower mandible border. It may serve as an additional reference for localizing the genial tubercle and the attachment of the genioglossus muscle to the mandible, although the preoperative radiological evaluation and the palpation of the GT are recommended to accurately isolate.

Evaluation of location and dimensions of genial tubercle in patients with class I and II occlusion with cone bean computed tomography images

Introdution: Obstructive sleep apnea syndrome has potentially significant physiological and psychological consequences. The main method to control the obstructive sleep apnea syndrome is surgical advancement of genioglossus muscle (GA) or genial tubercle (GTA). Therefore, for pre-operation arrangements, surgeons definitely need to know the exact location of genial tubercle and the muscles attached to it. The aim of this study was to evaluate the location and dimensions of genial tubercle in the patients with class I and II occlusion with cone bean computed tomography (CBCT). Methods:In this descriptive cross-sectional study, cone bean computed tomographyimages of 152 adults (76 males and 76 females) with class I and II occlusion were inspected and the location and dimensions of genial tubercle (Height =GTH / Width=GTW / the distance between the apices of central teeth and the Superior border of genial tubercle=LI-SGT / the distance between the inferior border of genial tubercle and the inferior border of mandible= IGT-IBM / the anterior diameter of mandible = MT) were evaluated. Patients were classified based on their gender and occlusion type.Independent Kolmogorov-Smirnov tests were used for data analysis and thedata analyzed using SPSS16 software. Results:In all the groups, GTH was located near GTW. The measured data for GTH, GTW, LI-SGT, IGT-IBM and MT were 8.6-06 .57 mm, 8.6-19.47 mm, 7.6-13.56 mm, 8.7-47.40 mm, and 14.11-57.78 mm, respectively. No significant difference was indicated for GTW and LI-SGT based on malocclusion and for LI-SGT based on gender (P>0.05). Conclusion:Various locations and different size of this structure among patients imply that it is necessary for treatment of obstructive sleep apnea to obtain a CBCT image before surgical operation