John B. Ludlow

Learn More
OBJECTIVES Cone beam computed tomography (CBCT), which provides a lower dose, lower cost alternative to conventional CT, is being used with increasing frequency in the practice of oral and maxillofacial radiology. This study provides comparative measurements of effective dose for three commercially available, large (12'') field-of-view (FOV), CBCT units: CB(More)
OBJECTIVES This study compares 2 measures of effective dose, E(1990) and E(2007), for 8 dentoalveolar and maxillofacial cone-beam computerized tomography (CBCT) units and a 64-slice multidetector CT (MDCT) unit. STUDY DESIGN Average tissue-absorbed dose, equivalent dose, and effective dose were calculated using thermoluminescent dosimeter chips in a(More)
OBJECTIVES This study provides effective dose measurements for two extraoral direct digital imaging devices, the NewTom 9000 cone beam CT (CBCT) unit and the Orthophos Plus DS panoramic unit. METHODS Thermoluminescent dosemeters were placed at 20 sites throughout the layers of the head and neck of a tissue-equivalent RANDO phantom. Variations in phantom(More)
OBJECTIVE To evaluate the type and prevalence of incidental findings from cone beam computed tomography (CBCT) of the maxillofacial region. Findings are divided into those that require (i) intervention/referral, (ii) monitoring, and (iii) no further evaluation. METHODS Three hundred consecutive CBCT scans conducted in the University of North Carolina(More)
OBJECTIVES Cone beam computed tomography (CBCT) images of ideally positioned and systematically mispositioned dry skulls were measured using two-dimensional and three-dimensional software measurement techniques. Image measurements were compared with caliper measurements of the skulls. STUDY DESIGN Cone beam computed tomography volumes of 28 skulls in(More)
BACKGROUND In 2007, the International Commission on Radiological Protection (ICRP) revised estimates of the radiosensitivity of tissues including those in the maxillofacial region. The authors conducted a study to reassess patients' risk related to common dental radiographic exposures using the 2007 ICRP recommendations. METHODS The authors used a(More)
INTRODUCTION In this study, we compared the precision of landmark identification using displays of multi-planar cone-beam computed tomographic (CBCT) volumes and conventional lateral cephalograms (Ceph). METHODS Twenty presurgical orthodontic patients were radiographed with conventional Ceph and CBCT techniques. Five observers plotted 24 landmarks using(More)
OBJECTIVES The aim of this study was to compare effective doses resulting from different scan protocols for cone-beam computerized tomography (CBCT) using International Commission on Radiological Protection (ICRP) 1990 and 2007 calculations of dose. STUDY DESIGN Average tissue-absorbed dose, equivalent dose, and effective dose for a ProMax 3D CBCT with(More)
BACKGROUND Bisphosphonates are used widely to manage skeletal disorders resulting from malignancies that destroy bone and from some metabolic bone diseases. A strong association between bisphosphonate treatment and the appearance of painful exposed nonvital bone in the mandible and maxilla after oral surgery has been reported in the last decade. Extensive(More)
OBJECTIVES Measurements of ideally positioned and systematically mis-positioned skulls were used to evaluate errors in linear measurements and symmetry ratios made with panoramic X-ray images. METHODS Digital panoramic images of 30 skulls placed in ideal, shifted and rotated positions, were assessed by measuring distances between anatomic points and(More)