The Relationship Between Cervical Headgear Treatment And Maxillary Third Molar Space: A Retrospective Controlled Study Original Research
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Abstract
Introduction: The effect of headgear on the space available for the eruption of upper third molars needed further investigation. Only a few studies looked at the after-treatment effect of headgear on that space, and none have evaluated the long-term effect after the average age of third molar eruption. Therefore, this retrospective study evaluated the short and long-term effects of cervical headgear on the space and eruption of the maxillary third molars and their long-term eruption status.
Materials and Methods: Records of Class II cases treated with cervical headgear were collected at the following time points: (T1) before treatment, (T2) after treatment, and (T3) taken at least 4 years after T2. An untreated control sample was collected from the Bolton-Brush study records. They were matched for age at each time point and malocclusion. Lateral cephalograms were used to measure the distance from the distal surface of the maxillary first molar (U6) to the pterygoid vertical plane (PTV). The third molar status at T3 was categorized into five groups: impacted, extracted, erupted, congenitally missing, and formation stage. Thirty-three cases were included in the cervical headgear group and 19 in the control group.
Results: The position of U6 changed significantly between the headgear and control group at T2 but was similar at T3. In the headgear group, the U6 was significantly distalized (3.3 ±2.9 mm) between T1 and T2 (P=0.006), however, there was a significant relapse of 5.9 (±4.6) mm between T2 and T3 (P<0.001). In the control group, the distance between U6 and PTV increased significantly from T1 to T2 (4.8 ±4.4mm) with minimal change from T2 to T3 (1.5 ±4.8mm). There was no significant relationship between headgear use and third molar status (p=0.108).
Conclusion: Headgear caused a temporary decrease in the U6-PTV distance that was recovered later. This decrease was not observed in the control group. Using cervical headgear to correct Class II malocclusion does not increase the risk of upper third molar impaction.
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References
Bishara SE, Andreasen G. Third molars: a review. Am J Orthod. 1983;83(2):131-7.
Grover PS, Lorton L. The incidence of unerupted permanent teeth and related clinical cases. Oral Surg Oral Med Oral Pathol. 1985;59(4):420-5.
Kumar Pillai A, Thomas S, Paul G, Singh SK, Moghe S. Incidence of impacted third molars: A radiographic study in People's Hospital, Bhopal, India. J Oral Biol Craniofac Res. 2014;4(2):76-81.
Kandasamy S, Woods MG. Is orthodontic treatment without premolar extractions always non-extraction treatment? Aust Dent J. 2005;50(3):146-51.
Almpani K, Kolokitha OE. Role of third molars in orthodontics. World J Clin Cases. 2015;3(2):132-40. Epub 2015/02/17.
Richardson M. The development of third molar impaction. Br J Orthod. 1975;2(4):231-4.
Kim TW, Artun J, Behbehani F, Artese F. Prevalence of third molar impaction in orthodontic patients treated nonextraction and with extraction of 4 premolars. Am J Orthod Dentofacial Orthop. 2003;123(2):138-45.
Cavanaugh JJ. Third molar changes following second molar extractions. Angle Orthod. 1985;55(1):70-6.
Miclotte A, Grommen B, Cadenas de Llano-Perula M, Verdonck A, Jacobs R, Willems G. The effect of first and second premolar extractions on third molars: A retrospective longitudinal study. J Dent. 2017;61:55-66. Epub 2017/04/01.
Cangialosi TJ, Meistrell ME, Jr., Leung MA, Ko JY. A cephalometric appraisal of edgewise Class II nonextraction treatment with extraoral force. Am J Orthod Dentofacial Orthop. 1988;93(4):315-24.
Ghosh J, Nanda RS. Evaluation of an intraoral maxillary molar distalization technique. Am J Orthod Dentofacial Orthop. 1996;110(6):639-46.
Flores-Mir C, McGrath L, Heo G, Major PW. Efficiency of molar distalization associated with second and third molar eruption stage. Angle Orthod. 2013;83(4):735-42.
Reimann S, Keilig L, Jager A, Brosh T, Shpinko Y, Vardimon AD, et al. Numerical and clinical study of the biomechanical behaviour of teeth under orthodontic loading using a headgear appliance. Med Eng Phys. 2009;31(5):539-46.
Shpack N, Brosh T, Mazor Y, Shapinko Y, Davidovitch M, Sarig R, et al. Long- and short-term effects of headgear traction with and without the maxillary second molars. Am J Orthod Dentofacial Orthop. 2014;146(4):467-76.
Miclotte A, Grommen B, Lauwereins S, Cadenas de Llano-Perula M, Alqerban A, Verdonck A, et al. The effect of headgear on upper third molars: a retrospective longitudinal study. Eur J Orthod. 2017;39(4):426-32.
Mitani H, Brodie AG. Three plane analysis of tooth movement, growth, and angular changes with cervical traction. Angle Orthod. 1970;40(2):80-94.
Ricketts RM. The influence of orthodontic treatment on facial growth and development. Angle Orthod. 1960;30(3):103-33.
Faul F, Erdfelder E, Lang AG, Buchner A. G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behav Res Methods. 2007;39(2):175-91.
Sokucu O, Ozturk F, Babacan H, Bicakci AA. Does rapid maxillary expansion affect the eruption of upper third molars? Angle Orthod. 2008;78(2):195-200. Epub 2008/02/07.
Bjork A, Skieller V. Growth in width of the maxilla studied by the implant method. Scand J Plast Reconstr Surg. 1974;8(1-2):26-33.
Ganss C, Hochban W, Kielbassa AM, Umstadt HE. Prognosis of third molar eruption. Oral Surg Oral Med Oral Pathol. 1993;76(6):688-93. Epub 1993/12/01.
Shoshani-Dror D, Shilo D, Ginini JG, Emodi O, Rachmiel A. Controversy regarding the need for prophylactic removal of impacted third molars: An overview. Quintessence Int. 2018;49(8):653-62. Epub 2018/08/16.