Comparison of Fracture Strength of Occlusal Splint Materials Manufactured by Three Different Methods: In Vitro Study

Abstract

Aim: This study aimed to compare the fracture resistance of occlusal splint materials fabricated using three different production methods. Materials and Methods: Digital designs of 10×10×2 mm blocks were prepared and fabricated using conventional, subtractive, and additive manufacturing (n=25). Supports were removed in all processes, and surface treatments were standardized. Fracture resistance tests were conducted using a universal testing machine with a 3 mm flat stainless steel compression tip at a loading speed of 1 mm/min. All tests were performed by the same operator under stable laboratory conditions. Maximum force at fracture was recorded in Newtons. Normality was assessed with the Shapiro Wilk test and intergroup differences were analyzed using the Kruskal-Wallis test followed by Bonferroni post hoc corrections (α=.05). Results: The subtractive manufacturing group showed the highest fracture resistance, followed by the additive and conventional groups (P<0.05). Conclusion: Digital fabrication techniques demonstrated superior mechanical performance compared to the conventional method, especially in terms of fracture resistance and clinical durability.

Keywords

• Occlusal splint
• PMMA
• CAD/CAM
• Additive manufacturing
• Subractive manufacturing
• Fracture strength

Üç Farklı Yöntemle Üretilen Okluzal Splint Materyallerinin Kırılma Dayanımlarının Karşılaştırılması: İn-Vitro Çalışma

Abstract

Amaç: Bu çalışmanın amacı, üç farklı üretim yöntemiyle hazırlanan oklüzal splint materyallerinin kırılma dayanımlarını karşılaştırmaktır. Gereç ve Yöntem: Dijital ortamda tasarlanan 10×10×2 mm boyutlarındaki örnekler; konvansiyonel (manuel olarak otopolimerizan akrilik ile), eksiltmeli (frezelenmiş PMMA bloklarla) ve eklemeli (DLP teknolojisiyle fotopolimer reçinelerden) yöntemlerle üretilmiştir (n=25). Her üretim sürecinde destek yapılar uzaklaştırılmış, yüzey işlemleri standart hale getirilmiştir. Kırılma dayanımı testleri, 3 mm çapındaki paslanmaz çelik düz kompresyon başlığı ve 1 mm/dk hızla çalışan universal test cihazı kullanılarak yapılmıştır. Tüm testler aynı operatör tarafından, sabit çevresel koşullarda gerçekleştirilmiştir. Maksimum kırılma kuvveti Newton cinsinden kaydedilmiştir. Veriler Shapiro-Wilk testi ile değerlendirilmiş, gruplar arası farklar Kruskal-Wallis testi ve Bonferroni düzeltmeleriyle analiz edilmiştir. Bulgular: Eksiltmeli üretim yöntemi en yüksek kırılma dayanımını göstermiş, bunu eklemeli ve konvansiyonel yöntem izlemiştir (P<0.05). Sonuç: Dijital üretim yöntemleri, konvansiyonel yönteme kıyasla daha üstün mekanik performans sunmaktadır.

Keywords

• Okluzal splint
• PMMA
• CAD/CAM
• Eklemeli üretim
• Eksiltmeli üretim
• Kırılma dayanımı

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