A posteriori registration and subtraction of panoramic compared with intraoral radiography.
OBJECTIVE
To demonstrate the feasibility of panoramic image subtraction for implant assessment.


METHODS
Three titanium implants were inserted into a fresh pig mandible. One intraoral and 2 panoramic images were obtained at baseline and after each of 6 incremental (0.3, 0.6, 1.0, 1.5, 2.0, 2.5 mm) removals of bone. For each incremental removal of bone, the mandible was removed from and replaced in the holding device. Images representing incremental bone removals were registered by computer with the baseline images and subtracted. Assessment of the subtraction images was based on visual inspection and analysis of structured noise.


RESULTS
Incremental bone removals were more visible in intraoral than in panoramic subtraction images; however, computer-based registration of panoramic images reduced the structured noise and enhanced the visibility of incremental removals.


CONCLUSIONS
The feasibility of panoramic image subtraction for implant assessment was demonstrated.
Deserno
Thomas M
TM
Department of Medical Informatics, Aachen University of Technology, Aachen, Germany. deserno@ieee.org
Rangarajan
Janaki Raman
JR
Hoffmann
Jens
J
Brägger
Urs
U
Mericske-Stern
Regina
R
Enkling
Norbert
N
D000818:Animals; D003627:Data Interpretation, Statistical; D015921:Dental Implants; D007090:Image Interpretation, Computer-Assisted; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008334:Mandible / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D016300:Radiography, Bitewing / Q000379:methods*; D019252:Radiography, Dental, Digital / Q000295:instrumentation / Q000379:methods; D011862:Radiography, Panoramic / Q000379:methods*; D013382:Subtraction Technique; D013552:Swine
D015921:Dental Implants