1
DENTAL RADIOGRAPHY: PRINCIPLES AND
TECHNIQUES (6TH EDITION) –
COMPREHENSIVE EXAM PREP GUIDE: STUDY
GUIDE | LATEST UPDATE 2026/2027 | PRACTICE
QUESTIONS AND ANSWERS | 100% CORRECT
ANSWERS | VERIFIED SOLUTIONS
This comprehensive practice examination is designed for candidates preparing for
dental radiography certification and board examinations, including the Dental
Assisting National Board (DANB) Radiation Health and Safety (RHS) exam and
the National Board Dental Hygiene Examination (NBDHE). It reflects the
2026/2027 content blueprint based on the 6th Edition of Dental Radiography:
Principles and Techniques by Joen Iannucci, DDS, MS, and Laura Jansen
Howerton, RDH, MS. The material covers all 35 chapters across eight parts,
including radiation basics, equipment and digital imaging, film imaging,
radiographer responsibilities, intraoral and extraoral techniques, normal
anatomy, and image interpretation. Each question includes verified solutions and
detailed rationales to help candidates master the scientific and clinical foundations
of dental radiography practice. This guide simulates certification-level difficulty
and supports focused professional exam preparation.
Table of Contents
I. Radiation Basics and Dental Image Characteristics
II. Equipment and Digital Imaging Basics
III. Film Imaging Basics
IV. Dental Radiographer Basics
V. Intraoral Technique Basics
VI. Extraoral Imaging Basics
VII. Normal Anatomy Basics
VIII. Image Interpretation Basics
, 2
Question 1: Who is credited with the discovery of X-rays in 1895?
A) Wilhelm Conrad Roentgen
B) Otto Walkhoff
C) C. Edmund Kells
D) William Coolidge
Correct Answer: A
Wilhelm Conrad Roentgen discovered X-rays on November 8, 1895, and was
awarded the first Nobel Prize in Physics in 1901 for this discovery. Otto Walkhoff
made the first dental radiograph, C. Edmund Kells was a pioneer in dental
radiography, and William Coolidge developed the hot cathode X-ray tube.
Question 2: Who took the first dental radiograph in the United States using a live
person?
A) Wilhelm Conrad Roentgen
B) Otto Walkhoff
C) C. Edmund Kells
D) William Rollins
Correct Answer: C
C. Edmund Kells, a New Orleans dentist, is credited with taking the first dental
radiograph in the United States using a live person in 1896. He also pioneered the
use of radiography in dental practice and was an early advocate for radiation
safety.
Question 3: What is the primary component of the dental X-ray tube head that
produces X-rays?
A) The tungsten filament in the cathode
B) The copper stem
C) The lead-lined housing
D) The aluminum filter
Correct Answer: A
X-rays are produced when high-speed electrons from the cathode strike the
tungsten target in the anode. The tungsten filament in the cathode generates
electrons through thermionic emission when heated. The other components serve
supporting roles in the X-ray production process.
, 3
Question 4: Which component of the dental X-ray tube head is responsible for
absorbing scattered radiation and reducing patient exposure?
A) The collimator
B) The aluminum filter
C) The lead collimator
D) The position-indicating device (PID)
Correct Answer: C
The lead collimator restricts the size of the X-ray beam, reducing patient exposure
by limiting the area irradiated. The aluminum filter removes low-energy (long-
wavelength) X-rays, the PID aims the beam, and the collimator specifically limits
beam size.
Question 5: What is the primary purpose of the aluminum filter in the dental X-ray
tube head?
A) To increase the energy of the X-ray beam
B) To remove low-energy, non-penetrating X-rays
C) To focus the X-ray beam
D) To absorb scattered radiation
Correct Answer: B
Aluminum filters remove low-energy (long-wavelength) X-rays that would only be
absorbed by the patient's skin and contribute to unnecessary radiation dose
without contributing to the diagnostic image. This process is called filtration.
Question 6: What is the recommended source-to-film distance for the paralleling
technique?
A) 8 inches
B) 12 inches
C) 16 inches
D) 20 inches
Correct Answer: C
The paralleling technique typically uses a 16-inch source-to-film distance to
reduce magnification and improve image sharpness. An 8-inch distance is used for
the bisecting technique, and longer distances increase magnification.
Question 7: What is the primary advantage of the paralleling technique over the
bisecting technique?
, 4
A) It requires less patient cooperation
B) It produces less image distortion and better anatomical accuracy
C) It uses a shorter source-to-film distance
D) It is easier to position the receptor
Correct Answer: B
The paralleling technique produces less image distortion because the film is
parallel to the long axis of the tooth and the central ray is perpendicular to both.
The bisecting technique produces more distortion but requires less patient
cooperation and is easier to position.
Question 8: The bisecting technique is also known as the:
A) Right-angle technique
B) Short-cone technique
C) Long-cone technique
D) Parallel technique
Correct Answer: B
The bisecting technique is also called the short-cone technique because it typically
uses an 8-inch source-to-film distance. The paralleling technique is known as the
long-cone technique because it uses a 16-inch distance.
Question 9: What is the primary purpose of the bite-wing technique?
A) To examine the apical regions of teeth
B) To examine the crowns of posterior teeth and alveolar crest
C) To examine the entire tooth including roots
D) To examine the temporomandibular joint
Correct Answer: B
Bite-wing radiographs are designed to examine the crowns of both maxillary and
mandibular posterior teeth and the alveolar crest. They are particularly useful for
detecting interproximal caries and evaluating bone levels.
Question 10: What size receptor is typically used for a full-mouth series on an
adult patient using the paralleling technique?
A) Size 0
B) Size 1
C) Size 2
D) Size 4
DENTAL RADIOGRAPHY: PRINCIPLES AND
TECHNIQUES (6TH EDITION) –
COMPREHENSIVE EXAM PREP GUIDE: STUDY
GUIDE | LATEST UPDATE 2026/2027 | PRACTICE
QUESTIONS AND ANSWERS | 100% CORRECT
ANSWERS | VERIFIED SOLUTIONS
This comprehensive practice examination is designed for candidates preparing for
dental radiography certification and board examinations, including the Dental
Assisting National Board (DANB) Radiation Health and Safety (RHS) exam and
the National Board Dental Hygiene Examination (NBDHE). It reflects the
2026/2027 content blueprint based on the 6th Edition of Dental Radiography:
Principles and Techniques by Joen Iannucci, DDS, MS, and Laura Jansen
Howerton, RDH, MS. The material covers all 35 chapters across eight parts,
including radiation basics, equipment and digital imaging, film imaging,
radiographer responsibilities, intraoral and extraoral techniques, normal
anatomy, and image interpretation. Each question includes verified solutions and
detailed rationales to help candidates master the scientific and clinical foundations
of dental radiography practice. This guide simulates certification-level difficulty
and supports focused professional exam preparation.
Table of Contents
I. Radiation Basics and Dental Image Characteristics
II. Equipment and Digital Imaging Basics
III. Film Imaging Basics
IV. Dental Radiographer Basics
V. Intraoral Technique Basics
VI. Extraoral Imaging Basics
VII. Normal Anatomy Basics
VIII. Image Interpretation Basics
, 2
Question 1: Who is credited with the discovery of X-rays in 1895?
A) Wilhelm Conrad Roentgen
B) Otto Walkhoff
C) C. Edmund Kells
D) William Coolidge
Correct Answer: A
Wilhelm Conrad Roentgen discovered X-rays on November 8, 1895, and was
awarded the first Nobel Prize in Physics in 1901 for this discovery. Otto Walkhoff
made the first dental radiograph, C. Edmund Kells was a pioneer in dental
radiography, and William Coolidge developed the hot cathode X-ray tube.
Question 2: Who took the first dental radiograph in the United States using a live
person?
A) Wilhelm Conrad Roentgen
B) Otto Walkhoff
C) C. Edmund Kells
D) William Rollins
Correct Answer: C
C. Edmund Kells, a New Orleans dentist, is credited with taking the first dental
radiograph in the United States using a live person in 1896. He also pioneered the
use of radiography in dental practice and was an early advocate for radiation
safety.
Question 3: What is the primary component of the dental X-ray tube head that
produces X-rays?
A) The tungsten filament in the cathode
B) The copper stem
C) The lead-lined housing
D) The aluminum filter
Correct Answer: A
X-rays are produced when high-speed electrons from the cathode strike the
tungsten target in the anode. The tungsten filament in the cathode generates
electrons through thermionic emission when heated. The other components serve
supporting roles in the X-ray production process.
, 3
Question 4: Which component of the dental X-ray tube head is responsible for
absorbing scattered radiation and reducing patient exposure?
A) The collimator
B) The aluminum filter
C) The lead collimator
D) The position-indicating device (PID)
Correct Answer: C
The lead collimator restricts the size of the X-ray beam, reducing patient exposure
by limiting the area irradiated. The aluminum filter removes low-energy (long-
wavelength) X-rays, the PID aims the beam, and the collimator specifically limits
beam size.
Question 5: What is the primary purpose of the aluminum filter in the dental X-ray
tube head?
A) To increase the energy of the X-ray beam
B) To remove low-energy, non-penetrating X-rays
C) To focus the X-ray beam
D) To absorb scattered radiation
Correct Answer: B
Aluminum filters remove low-energy (long-wavelength) X-rays that would only be
absorbed by the patient's skin and contribute to unnecessary radiation dose
without contributing to the diagnostic image. This process is called filtration.
Question 6: What is the recommended source-to-film distance for the paralleling
technique?
A) 8 inches
B) 12 inches
C) 16 inches
D) 20 inches
Correct Answer: C
The paralleling technique typically uses a 16-inch source-to-film distance to
reduce magnification and improve image sharpness. An 8-inch distance is used for
the bisecting technique, and longer distances increase magnification.
Question 7: What is the primary advantage of the paralleling technique over the
bisecting technique?
, 4
A) It requires less patient cooperation
B) It produces less image distortion and better anatomical accuracy
C) It uses a shorter source-to-film distance
D) It is easier to position the receptor
Correct Answer: B
The paralleling technique produces less image distortion because the film is
parallel to the long axis of the tooth and the central ray is perpendicular to both.
The bisecting technique produces more distortion but requires less patient
cooperation and is easier to position.
Question 8: The bisecting technique is also known as the:
A) Right-angle technique
B) Short-cone technique
C) Long-cone technique
D) Parallel technique
Correct Answer: B
The bisecting technique is also called the short-cone technique because it typically
uses an 8-inch source-to-film distance. The paralleling technique is known as the
long-cone technique because it uses a 16-inch distance.
Question 9: What is the primary purpose of the bite-wing technique?
A) To examine the apical regions of teeth
B) To examine the crowns of posterior teeth and alveolar crest
C) To examine the entire tooth including roots
D) To examine the temporomandibular joint
Correct Answer: B
Bite-wing radiographs are designed to examine the crowns of both maxillary and
mandibular posterior teeth and the alveolar crest. They are particularly useful for
detecting interproximal caries and evaluating bone levels.
Question 10: What size receptor is typically used for a full-mouth series on an
adult patient using the paralleling technique?
A) Size 0
B) Size 1
C) Size 2
D) Size 4
