Premolar extraction in orthodontics: Does it have any effect on patient′s facial height?
| Autor: | Abdolhamid Zafarmand, Mohamad-Mahdi Zafarmand |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Orthodontics
Lower anterior facial profile business.industry Dentistry Extrusive medicine.disease Class II malocclusion Facial height facial height medicine.anatomical_structure Upper anterior Premolar Medicine Original Article Biomechanics In patient Malocclusion business General Dentistry Anterior facial height premolar extraction |
| Zdroj: | Journal of International Society of Preventive & Community Dentistry |
| ISSN: | 2231-0762 |
| Popis: | Objectives: Facial esthetics is an important part of the orthodontic treatment. Many cases frequently require premolar extraction, either for relief of crowding or for profile change. Supposedly, extraction provides some vertical reduction. This investigation challenges the clinical effects of such treatment protocols. Patients and Methods: This was a retrospective and quasi-experimental study. Records of 60 patients in their post-pubertal age were randomly selected for this study. The criteria for ca se selection were: Class II Division I malocclusion with either two upper or four upper and lower first premolars extraction. Patients were not vertical-sensitive type of face. Pre- and post-treatment X-rays were scanned and digitized with Dolphin V 10.0 software. The X-rays of both groups were compared based upon the following cephalometric measurements: Lower anterior facial height (LAFH), Me-PP, Pal-MeGe, LAFH/total anterior facial height (TAFH) × 100, upper anterior facial height (UAFH)/TAFH × 100, U6 to PP, L6 to MP, and U6D-PTV. Results: In the four bicuspid group, a statistically significant increase was observed in all measurements: 2.53 mm increase in LAFH ( P ≤ 0.04), 2.92 mm increase in Me-PP ( P ≤ 0.01), 0.65° increase in Pal-MeGe ( P ≤ 0.02), 0.66° increase in LAFH/TAFH × 100 ( P ≤ 0.01), 1.26 mm increase in U6 to PP ( P ≤ 0.02), 1.96 mm increase in L6 to MP ( P ≤ 0.002), and 3.06 mm increase in U6D-PTV (P ≤ 0.0001). But a decrease of 0.66° in UAFH/TAFH × 100 ( P ≤ 0.01) was observed. In the two bicuspid group, a significant increase was generally recorded: 2.06 mm increase in LAFH ( P ≤ 0.05), 1.19° increase in Pal-MeGe ( P ≤ 0.02), 1.39 mm increase in L6 to MP ( P ≤ 0.002), and 2.37 mm increase in U6D-PTV ( P ≤ 0.004). Conclusions: The results of this study are indicative of no change in patient's facial height with bicuspid extraction. In fact, extrusive effect of all types of tooth movement mostly overcomes the benefits of wedging effect concept. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|