ABSTRACTS OF POSTER COMPETITION WINNERS
2nd Place Winner
Title:
The Effect of
Magnification on
Experimental Resolution
Presenter:
Eric Feuer
841 Eisenhower Drive
Pittsburgh, PA 15228
(412)512-8458
[email protected]
Authors:
Eric Feuer, Shahryar Khaliq, Adam
Feuer, Herbert L Ray, Department of
Endodontics, University of Pittsburgh
School of Dental Medicine.
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J U LY / A U G 2 0 1 6 | P E N N S Y LVA N I A D E N TA L J O U R N A L
Introduction:
The benefit of magnification for the
diagnosis and treatment of surgical and
non-surgical endodontic procedures is
well recognized. However, very little
has been reported on experimental
resolution (the ability to differentiate
two distinct points at close distance)
at different magnifications as compared
to theoretical resolution (the assumption
that resolution increases at a rate
inversely proportional to the increase
in magnification).
Objective:
To evaluate experimental versus
theoretical resolution at differ
Methods:
Five subjects participated in a visual
acuity test measuring using a USAF
1951 Resolution Test Chart, which
measures the smallest grouping of
black and white lines that a participant
can differentiate between at different
magnifications. A Carl Ziess Pico
microscope (Carl Zeiss, Oberkochen,
Germany) was used at 5x, 7.5x, 12.5x,
20x & 31.25x magnifications, with
standardized light and distance (no
magnification was used as control).
The smallest grouping of lines
identified by each participant was
normalized for magnification.
Friedman test was utilized for
statistical analysis.
Results:
5x magnification showed a smaller
corrected resolution than 7.5x
magnification, but each successive
increase in magnification showed a
steady decrease in normal resolution.
The Friedman test demonstrated a
statistically significant difference in
experimental resolution at different
magnifications (χ2(5)=14.6,
p=0.0056).
Conclusion:
Increasing magnification increases
experimental resolution, but this
increase is less than the predicted
theoretical resolution. This difference
becomes more pronounced with
higher magnifications.
Funding:
Funding was provided through the
AAE Resident Research Grant.