Yılmaz Umut ASLAN, Orhan ÖZTOPRAK, Yasemin KULAK ÖZKAN

Lamina veneer preparasyon derinliklerinin 3B sistemler ile değerlendirilmes

Amaç: Lamina veneer restorasyonlarında preparasyon derinliği, yapısal sağlamlığın ve tutuculuğun sağlanmasında temel faktörlerin başında gelir. Bu çalışmanın amacı, deneyimli bir prostodontist (PP) ve yüksek lisans protodonti öğrencisinin (PPS) lamina preparasyon derinliklerinin, preparasyon öncesinde ve sonrasında 3B tarayıcı ile farklılıklarının değerlendirilmesidir. Gereç ve yöntemler: PP ve PPS 20 adet çekilmiş insan maksiller santral kesiciyi değerlendirmiştir. Fasiyel preparasyon için 0,5 mm’lik derinlik rehberli frez kullanılmıştır. İnsizal preparasyon için ise 1 mm’lik champher frez kullanılmıştır. Dişler, 10 µm hassasiyetinde lazer tarayıcı ile taranmıştır. Dişler 3 kısıma (insizal, orta ve servikal) bölünmüş ve 5 noktadan incelenmiştir. Preparasyon yapılmamış ve yapılmış dişler üst üste çakıştırılarak Magics (Materialise NV, Belgium) 3B tarama yazılımında aralarındaki farklar incelenmiştir. İstatistiksel analiz tek yünlü ANOVA ile yapılmıştır (p < 0.05). Bulgular: PP sonuçları ortalama insizalde 0.328+0.045 mm, ortada 0.375+0.097 mm, servikalde ise 0.471+0.07 mm olurken, PPS sonuçları ortalama insizalde 0.323+0.056 mm, ortada 0.403+0.083 mm ve servikalde 0.462+0.075 mm olarak bulunmuştur. Sonuç: Bu sonuçlar, derinlik belirleyici frez kullanıldığında PP ve PPS benzer preparasyon hassasiyet gösterdiğini belirtmektedir.

Evaluation of laminate veneer preparation depth with 3D systems

Background: Preparation depth of laminate veneers are essential inretention and structural integrity of restorations. The aim of this studywas to evaluate the difference between a trained professionalprosthodontist (PP) and a postgraduate prosthodontics student (PPS)in the preparation depth of laminate veneers by scanning the toothwith a 3D scanner before and after the preparation.Methods: Twenty extracted human maxillary central incisors wereevaluated by a PP and PPS. A 0.5 mm depth guide bur was used infor facial reduction and a 1 mm incisal reduction was performed witha deep chamfer. The teeth were scanned with a laser scanner at anaccuracy of 10 µm. The teeth were separated into 3 parts (incisal,middle and cervical) and then 5 points were randomly selected on theunprepared tooth and then lapped over when the preparation hadbeen completed. The data of the difference was calculated in 3Dscanning software Magics (Materialise NV, Belgium). Statisticalanalysis were performed with one-way ANOVA (p < 0.05).Results: PP results showed mean values in the Incisal of0.328+0.045 mm, Middle of 0.375+0.097 mm and Cervical of0.471+0.07 mm. PPS results showed mean values in the Incisal of0.323+0.056 mm, Middle results of 0.403+0.083 mm and Cervicalresults of 0.462+0.075 mm.Conclusion: These results suggest that a PP or a PPS can bothachieve the same precision in the preparation using a depth guidebur.

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