The Comparative Investigation of Symphysıs Morphology In Class II,1 and Class II,2 Malocclusions

Abstract

Aim: The aim of this study was to investigate the symphysis morphology according to both rotation models and malocclusion types among the Class II,1 and Class II,2 malocclusions seen with deepbite. Material and Method: The study was carried on lateral cepholometric and hand-wrist radiographs of 358 subjects 177 Class II,1 and 181 Class II,2 which were characterized with Class II malocclusion and increased overbite. Both Class II,1 and Class II,2 subjects were divided into three subgroups, as Hypodivergent, Normodivergent and Hyperdivergent, based on their mandibular plane angle SN/GoGn . The morphologic differences of the symphysis among the rotation models were compared with ANOVA and Duncan tests, separately in each malocclusion group. Indepedent samples of t-test was used to compare the Class II malocclusion types in each rotation model. Results: Symphysis heigths were increased and symphysis widths were decreased with mandibular posterior rotation in Class II,1 and Class II,2 malocclusions characterized with deepbite. Also symphysis was more upright positioned according to the mandibular base and symphysis inclination was increased with mandibular posterior rotation. Besides, there were no significant differences between Class II,1 and Class II,2 malocclusions at Hypodivergent and Normodivergent rotation models. But there were significant differences at Hyperdivergent rotation model since the the lower and total symphysis heights were longer in Class II,1 malocclusions and symphysis was flatter in Class II,2 malocclusion. Conclusion: The type of mandibular rotation is effective on symphysis heigths, widths and inclinations in Class II,1 and Class II,2 malocclusions characterized with deepbite. Although Class II,1 and Class II,2 malocclusions are similar with regards to symphysis morphology except Hyperdivergent rotation model

Keywords

• Deepbite, Class II,1 malocclusion, Class II,2 malocclusion, Mandibular rotation models, Symphysis morphology

Simfizis Morfolojisinin Sınıf II,1 ve Sınıf II,2 Malokluzyonlarda Karşılaştırmalı Olarak İncelenmesi

Abstract

Amaç: Bu çalışmanın amacı, derin kapanışa sahip Sınıf II,1 ve Sınıf II,2 malokluzyonlu bireylerde simfizis morfolojisinin, hem rotasyon modellerine hem de malokluzyon tiplerine göre incelenmesidir. Gereç ve Yöntem: Çalışma derin kapanış ve Sınıf II malokluzyonla karakterize 177’si Sınıf II,1 ve 181’i Sınıf II,2 olmak üzere toplam 358 bireyin lateral sefalometrik ve el-bilek radyografileri üzerinde yürütülmüştür. Sınıf II,1 ve Sınıf II,2 malokluzyonlu bireyler ayrıca mandibular plan açıları SN/GoGn dikkate alınarak Hipodiverjan, Normodiverjan ve Hiperdiverjan olmak üzere 3 alt gruba ayrılmıştır. Ayrı ayrı her bir malokluzyon grubunda rotasyon modelleri arasında simfizis morfolojisi bakımından ortaya çıkan farklılıklar ANOVA ve Duncan testleri ile karşılaştırılmıştır. Ayrı ayrı her bir rotasyon modelinde Sınıf II malokluzyonların karşılaştırılmasında ise bağımsız iki grup arası farklılıkların t-testi kullanılmıştır. Bulgular: Derin kapanışla karakterize Sınıf II,1 ve Sınıf II,2 malokluzyonlarda mandibular posterior rotasyonla birlikte simfizis yükseklikleri artmış ve simfizis genişlikleri azalmıştır. Ayrıca mandibular posterior rotasyonla birlikte simfizis mandibular kaideye göre daha dik konumlanmış ve simfizis iç açısı artmıştır. Bunun yanısıra Sınıf II,1 ve Sınıf II,2 malokluzyonlar arasında Hipodiverjan ve Normodiverjan rotasyon modellerinde önemli farklılıklar bulunmamıştır. Hiperdiverjan rotasyon modelinde ise Sınıf II,1 malokluzyonda alt ve total simfizis yüksekliklerinin daha uzun olmasına ve Sınıf II,2 malokluzyonda simfizisin daha düz olmasına bağlı farklılıklar bulunmuştur. Sonuç: Mandibular rotasyon modeli, derin kapanışa sahip Sınıf II,1 ve Sınıf II,2 malokluzyonlarda simfizis yükseklikleri, genişlikleri ve eğimleri üzerinde etkilidir. Ancak Sınıf II,1 ve Sınıf II,2 malokluzyonlar Hiperdiverjan rotasyon modeli haricinde simfizis morfolojisi bakımından benzerdir.

Keywords

• Derin kapanış, Sınıf II,1 malokluzyon, Sınıf II,2 malokluzyon, Mandibular rotasyon modeli, Simfizis morfolojisi

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