Effects of Two Appliances Used in the Correction of Class II Malocclusion on Mandibular Symphysis Morphology: Biblock and Activator

Year 2025, Volume: 35 Issue: 4, 300 - 306, 21.10.2025

Berrak Çakmak , Meliha Rübendiz

https://doi.org/10.17567/currresdentsci.1452172

Abstract

Objective: This study aimed to evaluate and compare the effects of two functional appliances, the Activator (AA) and the Biblock (BA), on mandibular symphysis (MS) morphology in patients with Class II malocclusion.
Methods: Records of patients treated at the Department of Orthodontics, Ankara University, between 2011 and 2021 were retrospectively analyzed. Inclusion criteria were mandibular deficiency, optimal growth pattern, and CS2–CS3 cervical maturation stage. Twenty patients treated with the Biblock (10 females, 10 males; mean age: 13.52±1.36 years) were identified. An age- and sex-matched control group of 20 patients treated with the Activator (mean age: 13.78±1.18 years) was selected. Lateral cephalometric radiographs taken before and after treatment were evaluated for angular and linear changes. Intragroup comparisons were performed with paired t-tests, and intergroup comparisons with independent t-tests.
Results: The mean treatment duration was 17.39±5.94 months in the BA group and 17.03±4.37 months in the AA group. Both appliances significantly improved Class II malocclusion. Significant anterior MS changes were observed in both groups, except for B-Ida-Idp. Upper MS width remained unchanged, while significant increases occurred in the middle (AA: 0.4±0.5 mm; BA: 0.4±0.5 mm) and lower widths (AA: 0.9±0.2 mm; BA: 0.8 ± 0.7 mm) (P<.005). Intergroup comparisons showed greater reduction in Pg-B-Ida and greater increase in Pg-B in the BA group (P<.05).
Conclusion: Functional treatment flattened MS curvature, promoted forward growth of B and Pg points, and altered anterior MS morphology. The effects of AA and BA on MS morphology were largely similar.
Keywords: Class II malocclusion, Functional appliance, Biblock, Activator, Mandibular symphysis morphology

Keywords

Class II malocclusion , Functional appliance , Biblock , Activator , Mandibular symphysis morphology

Sınıf II Maloklüzyonun Düzeltilmesinde Kullanılan İki Apareyin Mandibular Simfiz Morfolojisi Üzerindeki Etkileri: Biblok ve Aktivatör

Abstract

Amaç: Amaç: Bu çalışmanın amacı, Sınıf II maloklüzyonları tedavi etmek için kullanılan iki fonksiyonel aparey olan Aktivatör (AA) ve Biblok'un (BA) mandibular simfiz (MS) morfolojisi üzerindeki etkilerini araştırmak ve karşılaştırmaktır.
Yöntemler: Mandibular retrognati ve optimum büyüme paterninden kaynaklanan iskeletsel Sınıf 2 maloklüzyonu olan 40 hasta bu retrospektif çalışmaya dahil edildi. BA grubunun seçilmesinin ardından (n=20, 10 erkek ve 10 kız, ortalama yaş=13,52±1,36), cinsiyet ve gelişim açısından bu grupla tam olarak eşleşen AA ile tedavi edilen aktif kontrol grubu (n=20, 10 erkek ve 10 kız, ortalama yaş=13,78±1,18) seçildi. Tüm hastalar T0'da CS2-CS3 servikal matürasyon aşamasındaydı. İskeletsel, dental ve MS ile ilgili sefalometrik değişkenler ölçüldü. Bulgular: Tedavi süresi BA ile 17,39±5,94 ay, AA ile 17,03±4,37 ay olarak bulundu. Sınıf II maloklüzyon her iki grupta da anlamlı olarak düzeldi. Her iki grupta da B-Ida-Idp hariç, MS'in anterior ölçümlerinde anlamlı değişiklikler vardı. Her iki grupta da üst MS genişliğinde değişiklik olmazken, orta genişlikte (AA:0,4±0,5 mm; BA:0,4±0,5 mm) ve alt genişlikte (AA:0,9±0,2 mm; BA:0,8±0,7 mm) anlamlı artış gözlendi (P<,005). Gruplar karşılaştırıldığında, Pg-B-Ida'daki azalma ve Pg-B'deki artış BA grubunda anlamlı olarak daha fazlaydı (P<,05).
Sonuç: Fonksiyonel tedavi ile MS eğriliği düzleşti, B ve Pg noktaları öne doğru büyüdü ve MS'nin ön morfolojisi değişti. AA ve BA'nın MS morfolojisi üzerindeki etkileri benzerdir.
Anahtar Kelimeler: Sınıf II maloklüzyon, Fonksiyonel aparey, Biblock, Aktivatör, Mandibular simfiz morfolojisi

Keywords

Sınıf II maloklüzyon , Fonksiyonel aparey , Biblock , Aktivatör , Mandibular simfiz morfolojisi

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