Radiology Final
An emergency eyewash station must be within ___________ of where processing chemicals are handled.
25 feet
Dental caries requires a ________________ loss of calcium and phosphorus before the decay can be detected radiographically.
40-50%
Biodegradable
A chemical that is capable of being broken down into harmless products by living organisms, such as those found in a wastewater treatment facility
Alkaline means having a pH of ___________.
Above 7.0
What appears radiographically as a radiolucent double triangle that is less than halfway through the dentin toward the pulp?
Advance proximal caries
A congenital absence of teeth is called _________________.
Anodontia
C-4: severe caries
Decay of enamel and dentin that penetrates > halfway through dentin toward pulp
C-3: advanced caries
Decay of the enamel and dentin; through the DEJ, but < halfway through the dentin to the pulp
The ________________________ of tooth structure allows more x-rays to pass through the tooth and darken the image; therefore caries appear radiolucent on the x-ray.
Demineralization
What is the best sequence for learning to identify normal radiographic anatomy?
Determine if: 1.) Maxilla or mandible 2.) Anterior or posterior 3.) Radiopaque or radiolucent
Case Type IV- advanced chronic (aggressive periodontitis)
Easily identified with a crestal bone loss > 50% (evidence of tooth position changes, drifting-> than 50% bone loss)
The hardest body structure that covers the crown of our teeth is _________________.
Enamel
List the tooth structures in the order of decreasing radiopacity:
Enamel, dentin, cementum, and pulp
The key to successfully interpreting radiographs for proximal surface caries is to examine the contact point between adjacent teeth and just apical to the
Estimated gingival margin
Caries appear radiopaque, BECAUSE more radiation is passing through the demineralization than the surrounding tissues.
First statement is FALSE (appears radiolucent) Second statement is TRUE
An optical illusion created by an increased radiolucency observed at the cervical area of the tooth is called mach banding. The mach banding effect increases when overlap error occurs.
First statement is FALSE (when PROXIMAL surfaces overlap) Second statement is TRUE
Excessive occlusal force may result in a widening of the periodontal ligament space. Widening of the periodontal ligament space is called furcation involvement.
First statement is TRUE Second statement is FALSE (triangulation is the widening of the PDL)
A periapical radiograph of a 10 yr old will most likely reveal developing permanent dentition. Evidence of a congenitally missing permanent tooth is called an impaction.
First statement is TRUE. Second statement is FALSE: it's called Anodontia
Significant bone loss that results in a radiolucency observed in the area between the roots of multirooted teeth is called
Furcation involvement
______________________ is inflammation of the gingiva and is limited to the soft tissue; gingivitis cannot be detected radiographically!
Gingivitis
A chemical with what pH would be most likely to cause severe eye irritation?
High pH (alkaline)
__________________________ is sometimes preferred by the practitioner to identify carious lesions on a radiograph.
High-contrast (low kVp)
Overlapping of the interproximal areas can render bitewing x-rays worthless for caries detection and can be corrected by adjusting the ___________________ angle of the PID.
Horizontal
What term describes bone loss that occurs in a plane parallel to the CEJ of adjacent teeth?
Horizontal describes bone loss
In general, what is the emergency recommendation if fixer or developer splashes into the eye?
Immediately flush with a steady stream of warm water for a minimum of 15 minutes
Teeth that form, but are unable to erupt are described as __________________.
Impacted teeth
Caries in the earliest stage is called
Incipient
What appears radiographically as a radiolucent notch that is less than half-way through the enamel?
Incipient proximal caries
Which of the following would not appear on a radiograph of the maxillary posterior region? -Maxillary sinus -Incisive foramen -Zygomatic arch -Hamulus
Incisive foramen
Decay that is found under a restoration or around it's margins is called _________________ decay.
Recurrent
Case Type III- moderate chronic (aggressive periodontitis)
Crest height >2.0 mm below CEJ (30-50% bone loss) Horizontal/vertical patterns of bone loss observed
Case Type II- slight chronic periodontitis
Crestal bone exhibits a loss of density with slight radiolucencies evident; triangulation is observed (up to 30% bone loss)
Rapidly growing or spreading decay that affects multiple teeth is termed _________________ decay
Rampant
What will help prevent accidental exposure to hazardous chemicals?
-Be familiar with the MSDS information regarding the product -Use the chemical in a well-ventilated area -Wash hands thoroughly after handling the chemical
What information should be included on an MSDS sheet?
-Chemical ingredients and common name -Potential hazards of working with the product -Requirements for safe handling and storage
The 3 calcified tooth structures that make up the tooth structure are:
-Enamel -Dentin -Cementum
Characteristics of acceptable bitewing
-IR placed correctly to record area of interest -Equal portion of the maxilla and mandible recorded -Occlusal/incisal plane of the teeth is parallel to the edge of the IR -Occlusal plane straight or slightly curved upward toward the posterior -Most posterior contact point between adjacent teeth recorded
List hazardous waste products created by the radiography department of a dental office.
-Lead foils from film packets -Used processing chemicals -Broken digital sensors
List the best recommendation for PPE for the dental radiographer when cleaning the processing equipment.
-Long sleeve barrier gown with rubber apron -Safety goggles -Mask -Nitrile gloves
What are some requirements of OSHA?
-Maintain inventory of all hazardous chemicals -Provide training for all personnel who handle the chemicals -Label all containers that will hold hazardous chemicals.
What are a few requirements of the eyewash station?
-Must be clearly labeled -Must be located within 25 feet or 10 seconds of where the chemical is handled -Flow of water must be easy to activate
Accidentally mixing developer with fixer, even in minute droplets, will result in:
-The release of an irritating sulfur dioxide gas -Contamination of the processing chemicals -Lower-quality radiograph
The end of the root canal is called the ___________________ ___________________.
Apical foramen
The term _________________ caries means that the decay has stopped or is no longer active; these lesions must be monitored regularly
Arrested
Acidic means having a pH of ___________.
Below 7.0
___________________ and recession of gingival tissue are necessary for the caries process to occur on the root surfaces.
Bone loss
__________________________decay appears radiographically as a round radiolucent hole in the middle of the tooth.
Buccal and lingual
Detection of ______________ is probably the most common reason for exposing dental radiographs.
Caries
Alveolar crests pointed in the anterior region and a radiopaque flat, smooth lamina dura 1.5 to 2.0 mm below the CEJ in the posterior region describes
Case type I: Gingivitis
Radiolucent changes observed on a radiograph such as a fuzzy, cupping-out of the crestal bone and a blunted appearance of the lamina dura in the anterior region describes
Case type II: Slight Chronic Periodontitis
What appears radiographically as an ill-defined crescent shaped radiolucency below the CEJ?
Cemental caries
A mandible landmark feature that may be imaged on a periapical radiograph of the maxillary posterior region is the:
Coronoid process
Which of the following would not appear on a radiograph of the mandibular anterior region? -Genial tubercles -Mental ridge -Coronoid process -Lingual foramen
Coronoid process would not appear on a mandibular anterior PA
Which bone type appears the most radiopaque?
Cortical outside layer
Appears as a radiopacity outlining the tooth root?
Lamina dura
The inverted Y landmark is composed of the intersection of which two structures?
Lateral wall of the nasal cavity and anterior border of the maxillary sinus
Carious lesions often appear ________severe on an x-ray than it may actually be clinically.
Less
Which of the following would not appear on a radiograph of the maxillary anterior region? -Nasal septum -Median palatine suture -Maxillary tuberosity -Inverted Y
Maxillary tuberosity
A chemical manufacturer may not have to reveal ingredients of a product unless a ______________ ____________ arises when a radiographer is using the chemical.
Medical emergency
What is the synthetic rubber used in utility gloves that protect the radiographer when handling chemicals?
Nitrile
Do all radiographic errors created the need to re-expose the patient? How do we determine whether to re-take an image or not?
No, you don't always need to retake if the error doesn't affect the area of interest.
What must a competent dental hygienist and dental assistant be able to identify?
Normal anatomy
Case Type I- gingivitis
Not seen on x-ray (crest is 1.5-2.0 mm below and parallel to the CEJ)
Dentists are required by _____________ to obtain and keep on file an MSDS for every chemical product used in the practice
OSHA
What two agencies are responsible for the development of safe handling standards for hazardous chemicals and materials used in the radiographic process.
OSHA & EPA (U.S. Environmental Protection Agency)
Radiographs are very helpful in the detection of proximal decay; however their use in the detection of ________________ decay is limited
Occlusal
What agency sets and enforces regulations that protect the radiographer from infection in the oral health care setting?
Occupational Safety and Health Administration (OSHA)
C-1: incipient caries
Penetrates < halfway through the enamel
C-2: moderate caries
Penetrates > halfway through the enamel toward the DEJ
_____________________________ are the diseases that affect both soft tissues and bone around the teeth.
Periodontal diseases
_________________________ is the result of infection and includes alveolar bone loss.
Periodontitis
What cannot be determined from a radiograph?
Pocket depth
Define alveolar process.
Portion of the maxilla or mandible that surrounds and supports the teeth
Radiographs are best at detecting incipient caries on what tooth surface?
Proximal
Which of the following would not appear on a radiograph of the mandibular posterior region? -Mental foramen -Pterygoid plate -Mandibular canal -Mylohyoid ridge
Pterygoid plate
Out of the enamel, cementum, dentin, and pulp, which one appears radiolucent?
Pulp is more radiolucent
The only non-calcified tooth structure is the ________________.
Pulp is non-calcified
The interaction of fixer with the silver ions in the emulsion of film produces _____________ _____________ ___________.
Silver thiosulfate complex
Which one does not appear radiopaque? -Ridge -Sinus -Tubercles -Process
Sinus
When nutrient canals open at the surface of the bone, they often appear radiographically as what?
Small radiolucent dots
Which one does not appear radiolucent? -Foramen -Suture -Canal -Spine
Spine
Extra teeth are called _________________.
Supernumerary teeth
Describe the radiographic appearance of the PDL:
Thin, radiolucent (black) border between the lamina dura and the root
Describe the radiographic appearance of the lamina dura:
Thin, radiopaque (white) border that outlines the root of the tooth
What causes the bone to have a mixed radiopaque-radiolucent appearance?
Trabeculae patterns
Proximal carious lesions appear
Triangular
Occlusal trauma may be identified on x-ray by a widening of the PDL; this finding is called
Triangulation
The key to successfully interpenetrating radiographs for occlusal caries is to examine
Under the occlusal surface for changes in dentin
Which of the following is LEAST likely to require special consideration prior to discharging into the waste stream : -Lead foils from intraoral film packets -Used fixer -Used developer -Digital imaging equipment`
Used developer
Incorrect ___________________ angulation can reveal inaccurate bone loss.
Vertical
_______________________________ are the most useful for examining the periodontium; periapicals are helpful as well provided they are done using the paralleling technique.
Vertical bitewings
What facial bone would most likely appear on a periapical radiograph?
Zygoma
On a periapical radiograph of the maxillary molars, what may be recorded superimposed over the roots of the teeth?
Zygomatic process
Limitations of x-rays for detection of Periodontal disease:
a. 2-dimensional image of 3-dimensional object leads to superimposition of structures b. Changes in soft tissue are not imaged c. Cannot distinguish between treated versus untreated disease (active/inactive) d. Actual destruction is more advanced clinically
Periodontal bone changes that can be recorded on a radiograph:
a. Alveolar crestal irregularities b. Interdental alveolar bone changes c. Pattern of bone loss (horizontal/vertical) d. Distribution of bone loss (localized/generalized) e. Severity of bone loss (slight/moderate/advanced) f. Furcation involvement
Some contributing factors that add to the risk for periodontal disease are:
a. Amalgam overhangs b. Poorly contoured crown margins c. Calculus deposits
Name some normal anatomy imaged on intraoral radiographs of the maxillary arch:
a. Nasal septum b. Anterior nasal spine c. Median palatal suture d. Maxillary tuberosity e. Incisive foramen f. Maxillary sinus
The three conditions that resemble caries on an x-ray are:
a. Nonmetallic restorations (composite/silicate/acrylic resin) b. Cervical burnout c. Mach band effect
The four locations on a tooth that caries can occur are:
a. Proximal (mesial and distal) b. Occlusal c. Buccal/lingual d. Cemental (root caries)
Name some normal anatomy imaged on intraoral radiographs of the mandibular arch:
a. Ramus b. Alveolar process c. Condyle d. Coronoid process e. Mandibular notch f. Mandibular foramen g. Mental foramen h. Mandibular canal
