The effect of non-extraction treatment on the dimensions of mandibular symphysis in patients with class I malocclusion

Yıl 2015, , 68 - 74, 21.04.2015

Nehir Canıgür Bavbek , Seçil Açar

https://doi.org/10.17214/aot.32082

Öz

OBJECTIVE: The aim of this retrospective study was to evaluate the short- and long-term effects of mandibular incisor movement due to non-extraction treatment on dimensions of mandibular symphysis (MS).

MATERIALS AND METHOD: Lateral cephalograms (before treatment, TB; after treatment, TS; retention, P) of 20 females classified as skeletal class 1 (ANB:0-4°), dental class I and having an optimal vertical growth direction (SN/GoGN: 32±6°) were selected from the archive of the Department of Orthodontics, Faculty of Dentistry, Gazi University. These subjects had mean chronological age of 14.9±3.3 years and mean mandibular crowding of 2.6±1.7 mm. On the cephalograms, 7 angular, 11 linear measurements were done in order to determine skeletal characteristics, position of the mandibular incisor and dimensions of MS. The width of MS and the amount of bone around the mandibular incisor were determined at three levels (crest ridge, center of rotation and root apex of the incisor). Statistical analyses were performed by using One-Way ANOVA to evaluate intergroup differences followed by a post-hoc Tukey test. Correlation analyses were performed by using Pearson correlation test (p<0.05).

RESULTS: Mandibular incisor protruded significantly with treatment (Co/1°, 1/MP°: p<0.05; 1/NB°, 1-NB: p<0.01) and bone thickness at crest ridge level was significantly lower at TS (p<0.05) and at P (p<0.001) when compared to TB. However, bone thickness at the center of rotation and root apex, and the MS height were not affected from treatment (p>0.05). There were no correlations between age at TB, total treatment time, amount of crowding and mandibular incisor protrusion with changes in crest ridge bone thickness (p>0.05).

CONCLUSION: The mandibular incisor protrusion seen after non-extraction treatment caused a decrease in bone thickness at the crest ridge level, and it was maintained at the retention period.

Anahtar Kelimeler

Malocclusion, Angle class I, mandibular symphysis, orthodontics

Sınıf I maloklüzyona sahip bireylerde çekimsiz sabit ortodontik tedavinin mandibular simfiz boyutları üzerine etkisinin değerlendirilmesi

Öz

AMAÇ: Bu retrospektif çalışmanın amacı çekimsiz sabit tedavi ile meydana gelen alt kesici diş hareketinin, mandibular simfiz (MS) boyutlarına kısa ve uzun dönemdeki etkilerini araştırmaktır.

GEREÇ VE YÖNTEM: Gazi Üniversitesi Diş Hekimliği Fakültesi, Ortodonti Anabilim Dalı arşivinde bulunan hasta kayıtları arasından, iskeletsel sınıf 1 (ANB:0-4°), dişsel Sınıf I, optimal büyüme yönü gösteren (SN/GoGN: 32±6°), ortalama yaşları 14.9±3.3 yıl ve alt çenedeki ortalama çapraşıklık miktarı 2.6±1.7 mm olan 20 kız bireyin tedavi başı (TB), tedavi sonu (TS) ve pekiştirme dönemi (P) lateral sefalometrik filmleri değerlendirildi. Sefalometrik filmler üzerinde iskeletsel yapılar, alt kesici dişin pozisyonu ve MS boyutlarına

ilişkin 7 açısal 11 doğrusal ölçüm yapıldı. MS genişliği ve dişi çevreleyen kemik miktarı üç seviyede (kret tepesi, alt kesici dişin rotasyon merkezi ve kök apeksi) tespit edildi. TB, TS ve P dönemlerine ait ölçümler arasında ortalamalar yönünden farkın önemliliği tek yönlü ANOVA testi ile, farka neden olan gruplar Tukey post-hoc testi ile, korelasyonlar ise Pearson korelasyon testi kullanılarak araştırıldı (p<0.05).

BULGULAR: Alt kesici dişlerin tedavi ile protrüze olduğu (Co/1°, 1/MP°: p<0.05; 1/NB°, 1-NB: p<0.01); kret tepesindeki kemik miktarının TS (p<0.05) ve P (p<0.001) döneminde TB’ye göre anlamlı olarak azaldığı görüldü. Ancak rotasyon merkezi ve apeks seviyesindeki kemik miktarları ile simfiz yüksekliğinin tedaviden etkilenmediği görüldü (p>0.05). Hastanın TB yaşı, tedavi süresi, TB çapraşıklık miktarı ve alt kesici dişin protrüzyon miktarının, kret seviyesindeki kemiğin değişimiyle bir etkileşimi bulunmadı (p>0.05).

SONUÇ: Çekimsiz ortodontik tedaviyle görülen alt kesici diş protrüzyonu, kret seviyesindeki alveol kemik kalınlığının azalmasına neden olmuştur ve pekiştirme döneminde bu değişim korunmuştur.

Anahtar Kelimeler

Maloklüzyon, mandibular simfiz, ortodonti, Angle sınıf I

Kaynakça

• 1. Buschang PH, Julien K, Sachdeva R, Demirjian A. Childhood and pubertal growth changes of the human symphysis. Angle Orthod 1992;62:203-10.
• 2. Hoenig JF. Sliding osteotomy genioplasty for facial aesthetic balance: 10 years of experience. Aesthetic Plast Surg 2007;31:384-91.
• 3. Gould SJ. The exaptive excellence of spandrels as a term and prototype. Proc Natl Acad Sci USA 1997;94:10750-5.
• 4. Gould SJ. The Structure of Evolutionary Theory. 1st edn. Cambridge, Mass: Belknap Press of Harvard University Press; 2002. p.1-1464.
• 5. Sherwood RJ, Hlusko LJ, Duren DL, Emch VC, Walker A. Mandibular symphysis of large-bodied hominoids. Hum Biol 2005;77:735- 59.
• 6. Al-Khateeb SN, Al Maaitah EF, Abu Alhaija ES, Badran SA. Mandibular symphysis morphology and dimensions in different anteroposterior jaw relationships. Angle Orthod 2014;84:304-9.
• 7. Gracco A, Luca L, Bongiorno MC, Siciliani G. Computed tomography evaluation of mandibular incisor bony support in untreated patients. Am J Orthod Dentofacial Orthop 2010;138:179-87.
• 8. Swasty D, Lee J, Huang JC, Maki K, Gansky SA, Hatcher D, et al. Cross-sectional human mandibular morphology as assessed in vivo by cone-beam computed tomography in patients with different vertical facial dimensions. Am J Orthod Dentofacial Orthop 2011;139:e377- 89.
• 9. Yamada C, Kitai N, Kakimoto N, Murakami S, Furukawa S, Takada K. Spatial relationships between the mandibular central incisor and associated alveolar bone in adults with mandibular prognathism. Angle Orthod 2007;77:766-72.
• 10. Swasty D, Lee JS, Huang JC, Maki K, Gansky SA, Hatcher D, et al. Anthropometric analysis of the human mandibular cortical bone as assessed by cone-beam computed tomography. J Oral Maxillofac Surg 2009;67:491-500.
• 11. Nauert K, Berg R. [Evaluation of labio-lingual bony support of lower incisors in orthodontically untreated adults with the help of computed tomography]. J Orofac Orthop 1999;60:321-34.
• 12. Yared KF, Zenobio EG, Pacheco W. Periodontal status of mandibular central incisors after orthodontic proclination in adults. Am J Orthod Dentofacial Orthop 2006;130:6.e1-8.
• 13. Wehrbein H, Bauer W, Diedrich P. Mandibular incisors, alveolar bone and symphysis after orthodontic treatment. A retrospective study. Am J Orthod Dentofacial Orthop 1996;110:239-46.
• 14. Molina-Berlanga N, Llopis-Perez J, Flores-Mir C, Puigdollers A. Lower incisor dentoalveolar compensation and symphysis dimensions among Class I and III malocclusion patients with different facial vertical skeletal patterns. Angle Orthod 2013;83:948-55.
• 15. Gütermann C, Peltomäki T, Markic G, Hänggi M, Schätzle M, Signorelli L, et al. The inclination of mandibular incisors revisited. Angle Orthod 2014;84:109-19.
• 16. Esenlik E, Alakuş Sabuncuoğlu F, Gülşen A. Şiddetli sınıf III ve sınıf I maloklüzyonlu vakalarda alveolar yapıların ve simfiz bölgesinin de- ğerlendirilmesi. Süleyman Demirel Üniv Diş Hek Fak Derg 2010;2:35-44.
• 17. Wonglamsam P, Manosudprasit M, Godfrey K. Facio-lingual width of the alveolar base. Aust Orthod J 2003;19:1-11.
• 18. Handelman CS. The anterior alveolus: its importance in limiting orthodontic treatment and its influence on the occurrence of iatrogenic sequale. Angle Orthod 1996;66:95-109.
• 19. Uysal T, Yagci A, Ozer T, Veli I, Ozturk A. Mandibular anterior bony support and incisor crowding: is there a relationship? Am J Orthod Dentofacial Orthop 2012;142:645-63.
• 20. Garib DG, Yatabe MS, Ozawa TO, da Silva Filho OG. Alveolar bone morphology under the perspective of the computed tomography: defining the biological limits of tooth movement. Dental Press J Orthod 2010;15:192-205.
• 21. Yu Q, Pan X, Ji G, Shen G. The association between lower incisal inclination and morphology of the supporting alveolar bone--A conebeam CT study. Int J Oral Sci 2009;1:217-23.
• 22. Aki T, Nanda RS, Currier GF, Nanda SK. Assessment of symphysis morphology as a predictor of the direction of mandibular growth. Am J Orthod Dentofacial Orthop 1994;106:60-9.
• 23. Czarnecki ST, Nanda RS, Currier GF. Perceptions of a balanced profile. Am J Orthod Dentofacial Orthop 1993;104:180-7.
• 24. Abdelkarim A. Myths and facts of cone beam computed tomography in orthodontics. J World Fed Orthod 2012;1:e3-e8.
• 25. American Academy of Oral and Maxillofacial Radiology. Clinical recommendations regarding use of cone beam computed tomography in orthodontics. Position statement by the American Academy of Oral and Maxillofacial Radiology. Oral Surg Oral Med Oral Pathol Oral Radiol 2013;116:238-57.