20Mar 2017

DENTO-ALVEOLAR EFFECTS OF MEMORAX VERSUS HYRAX RAPID PALATAL EXPANDERS: A COMPARATIVE CBCT STUDY.

  • Associate Professor, Department of Orthodontics, Faculty of Dental Medicine for girls, Al-Azhar University,Cairo, Egypt.
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Background: Rapid maxillary expansion usually associated with dental tipping of the anchor teeth, but the aims of the treatment are always to achieve minimal dental and maximum skeletal effects. The objective of the present study was to evaluate and compare the effect of memory palatal split screw (Memorax) to that of conventional Hyrax rapid palatal expanders on dento-alveolar structures, which were measured and recorded by Cone beam computed tomography (CBCT). Materials and Methods: It was conducted over 14 subjects of adolescent patients with bilaterally constricted maxillary arch, with age ranged from 12ys to 15ys, with a mean of 13.6 ± 1.4 divided equally into two groups; the Memorax group and the Hyrax group. For all subjects, maxillofacial CBCTs were taken before expansion (T1) and after 3 months at the time of removal of the expanders (T2). 10 dental measurements were taken (5 linear and 5 angular). Data were explored for normality using Kolmogorov-Smirnov test of normality. Paired t test was used to compare mean values of before and after treatment. Independent (unpaired) test was used to compare between the two groups. Results: There was no significant difference in the percent change after using both expanders, except in the inter-premolar apex width, where the percent change was significantly greater in the Memorax group (p=0.0082), and in the inter-premolar angle, where the percent change was significantly greater in the Hyrax group (p=0.0096), Conclusion: In the premolar area, Memorax produced bodily movement expansion pattern, while Hyrax showed more tipping of the anchor teeth.

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[Tarek Hassan Marei and Fatma Abdel Aziz Abdel Samad. (2017); DENTO-ALVEOLAR EFFECTS OF MEMORAX VERSUS HYRAX RAPID PALATAL EXPANDERS: A COMPARATIVE CBCT STUDY. Int. J. of Adv. Res. 5 (Mar). 422-430] (ISSN 2320-5407). www.journalijar.com

Tarek Hassan Marei
Associate Professor, Department of Orthodontics, Faculty of Dental Medicine for girls, Al-Azhar University,Cairo,Egypt.

DOI:

Article DOI: 10.21474/IJAR01/3529      
DOI URL: http://dx.doi.org/10.21474/IJAR01/3529

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