Effect of Processing on the Dimensional Accuracy of Maxillary Complete Denture

Abstract

The aim of this study was to evaluate the linear dimensional changes of conventional heatpolymerized acrylic resin during the processing stages. Metal pins were placed into the central fossae of the right and left first premolars and molars and cingulum area of the right central tooth on tooth aran gement stage. Anteroposterior and tranvers lenght measurements between reference points were doneby using a digital calliper Mitutoyo, Japan by three investigators at different times. Measurements were performed after try-in control , processing, polishing stages and storage in water for one month.Comparison of the rate of the changes for the stages according to the control group and between the stages were performed by 'repeated measures analysis of variance' ANOVA . Results showed a decrease in anteroposterior measurements after processing and polishing stages with regard to the control group.The increase in the values with regard to the initially decreasing measurements in the samples stored in water for 1 month was not found statistically significant p>0.05 . Besides, it was observed that this increase was not proportional to the dimensional reduction. However, statistically significant differences were only determined in the processing stage with regard to the control group in the transvers measurements p

Keywords

• Acryclic resin, Dimensional accuracy , Polimerization, Water sorption,

Maksiller tam protezin boyutsal hassasiyeti üzerinde işlememenin etkisi

Abstract

Çalışmanın amacı, ısı ve basınç altında geleneksel yöntem ile polimerize olan kaide rezininde hazırlama aşamalarının lineer boyutsal değişim üzerindeki etkilerini incelemektir. Çalışma örneği olan maksiller tam protezlerin n=8 sağ ve sol 1. premolar ve molar dişlerinin santral fossalarına ve sağ santral dişin singulum bölgesine referans noktası olarak metal pinler yerleştirildi. Pinler arasındaki anteroposterior ve meziodistal transvers boyut ölçümleri, üç araştırmacı tarafından ayrı zamanlarda 0.05 mm hassaslığında dijital kumpas Mitutoyo, Japonya ile gerçekleştirildi. Ölçümler diş dizimi kontrol , mufla içerisinde polimerizasyon, polisaj ve suda 1 ay bekletilme sonrasında tekrarlandı. Boyutların kontrol grubuna göre ve birbirleri arasındaki değişim oranları istatistiksel olarak ‘tekrarlanan ölçümlerde varyans analizi’ ANOVA ile karşılaştırıldı. Bulgular, anteroposterior ölçümlerde kontrol grubuna göre mufla içerisinde polimerizasyon ve polisaj sonrası azalma olduğunu gösterdi. Başlangıç ölçümüne göre azalan değerlerin 1 ay suda bekletilen örneklerde artış göstermesi istatistiksel olarak anlamlı bulunmadı p>0.05 . Aynı zamanda bu artışın azalma ile orantılı olmadığı da gözlendi. Oysaki, transvers boyut ölçümlerinde sadece kontrol grubuna göre mufla içerisinde polimerizasyon sonrasında istatistiki olarak anlamlı sonuçlar belirlendi p

Keywords

• Akrilik rezin, Boyutsal hassasiyet, Polimerizasyon, Su absorbsiyonu

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