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R A Radke

Publications and source records attributed to R A Radke.

6 recordsLinked to original sources

A comparative study of fracture resistance between morphologic dowel and cores and a resin-reinforced dowel system in the intraradicular restoration of structurally compromised roots.

The intraradicular reinforcement of structurally compromised roots has been advocated for endodontically treated teeth with thin remaining walls. The purpose of this in vitro study was to investigate the validity of intraradicular reinforcement. After the crowns were removed, forty structurally weakened central incisors were divided into two main groups for morphologic dowel rehabilitation or resin reinforcement and dowel rehabilitation. Within both these groupings, half the specimens were ferruled to assess the effects of a ferrule on fracture resistance. All dowels were cemented with resin cements. The resistance to a simulated masticatory load of a resin-reinforced post and core system was significantly greater than that of a morphologic post and core procedure. When a bonded resin reinforcement and dowel cementation was used on structurally weakened roots, there was no statistically significant difference between post and core restorations that used a ferrule and those without a ferrule.

Analysis of Variance↗

The mandibular incisor: rethinking guidelines for post and core design.

In post and core research, little attention has been given to the tooth with minimal bulk and mesialdistal width. The purpose of this in vitro study was to investigate retention and fracture characteristics of lower incisors restored with variable dowel designs. Fifty freshly extracted mandibular incisors were endodontically treated. Four groups of 10 teeth, decoronalized and dowel- and core-restored, were tested for retention characteristics and fracture resistance. One group of 10 teeth restored with composite resin in intact natural crown acted as controls. Dowel variables included a prefabricated round cross-sectional design and a morphologic dowel that reproduced the canal space. A universal testing machine created tensile and transverse loads, and failure was measured and recorded. Results showed no difference in resistance to transverse loading between morphological and standardized dowels (p > 0.05). However, when analyzing modes of failure, ferruled morphological post and core design was less likely to result in a catastrophic root or post fracture. In addition, morphological dowels were significantly more retentive than standardized round dowels in teeth with narrow cross-sections (p = 0.007). This study also reaffirmed the findings of previous investigations, that the intact natural crown of an endodontically treated tooth provides maximum resistance to root fracture.

Analysis of Variance↗

Retention of cast endodontic posts: comparison of cementing agents.

Zinc phosphate, glass-ionomer, and polycarboxylate cements were compared with a composite for ability to retain cast gold posts in prepared root canals of extracted teeth. Zinc phosphate and glass-ionomer cements were found to be more retentive than polycarboxylate cement and composite.

Cementation↗