Defense Date


Document Type


Degree Name

Master of Science



First Advisor

Karan Replogle

Second Advisor

Samuel Black


The purpose of this in-vitro study is to compare the accuracy and reliability of a 3rd and 4th generation electronic apex locator (EAL) in locating the apical foramen when using insulated and non-insulated K files. Forty extracted human adult single-rooted teeth were coronally sectioned and placed in agar. EAL determined tooth length measurements were compared to actual tooth measurements. Comparisons to the standard measures used correlation and paired t-test. Preliminary comparisons of the groups used ANOVA to compare the means and the Brown-Forsythe test to compare variance. In the final analyses, the measurements were compared using a repeated-measures mixed-model multiway ANOVA that allowed for heterogeneous variance in the subgroups. Findings were that accuracy is not different due to insulation in the Root ZX group (p-value=0.50) but is improved in the Elements Diagnostic Unit group (p-value<.001). Reliability is nominally improved with insulation in both the Root ZX and Elements Diagnostic Unit.


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Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

August 2011

Included in

Dentistry Commons