DENTAL HYGIENE NATIONAL BOARD EXAM
2026 QUESTIONS WITH SOLUTIONS GRADED
A+
◉ During the intraoral examination, a translucent-to-whitish
irregular film on the buccal mucosa is noted. The film is not
removable with gauze. Which of the following conditions is MOST
likely present? Answer: Hyperkeratinization
RATIONALE: Hyperkeratinization can result from constant low-
grade irritations such as cheek biting, which causes an abnormal
layer of keratin to develop. The client needs to be questioned
regarding parafunctional oral habits. Hyperplasia is an increase in
the number of cells whereas linea alba presents as a whitish,
horizontal, elevated line on the buccal mucosa at the height of the
occlusal plane. Also whitish in appearance, leukoplakia is
characterized as white patches that sometimes appear fissured, may
cause discomfort, cannot be scraped off and are considered
precancerous.
◉ When comparing permanent and primary molars, which of the
following statements is TRUE? Answer: Primary molars have larger
pulp chambers.
,RATIONALE: The pulp chambers of primary molars are larger than
those of the permanent molars. Second primary molars, not first
primary molars, have anatomy similar to that of the first permanent
molars. Primary molars have the same number of roots as
permanent molars; note that neither primary molars nor permanent
molars are classified as succedaneous teeth. A succedaneous tooth is
a permanent tooth that replaces a primary tooth. Thus, permanent
incisors are succedaneous, but permanent molars are not. The root
trunks of primary molars are very short in comparison with those of
permanent molars
◉ John Jeffry, a 45-year-old man, calls the dental office to request an
appointment for an oral examination. After discovering that he has
cerebral palsy, the office manager tells Mr. Jeffry that he cannot be
treated in the office due to his condition. Which of the following
BEST describes the behavior being demonstrated by the office
manager? Answer: This behavior is an example of discrimination
according to the Americans with Disabilities Act.
RATIONALE: This illegal behavior is an example of discrimination
according to the Americans with Disabilities Act (ADA). Based upon
the ADA, dental practices can neither refuse treatment based on a
client's disability nor can they prescreen clients to determine
whether they will provide care. Although the Equal Rights
Amendment affords important protection to all citizens, it has no
bearing on the provision of dental treatment.
,◉ Which of the following correctly ranks the tissues in order of
MOST sensitive to LEAST sensitive to ionizing radiation? Answer:
Reproductive, lymphatic, endocrine, digestive, nervous
RATIONALE: In general, younger cells with a high rate of
metabolism, an increased proliferation and growth rate, and a
decrease in specialization are more susceptible to radiation-induced
biologic changes. Therefore, reproductive organs represent tissue
with cells that are most radiosensitive, whereas the nervous system
is composed of cells considered to be the most radioresistant. In
descending order of radiosensitivity are lymphatic, endocrine, and
digestive tissues. An important concept, tissues that are less
sensitive to radiation-induced biological changes will be more
specialized, have lower rates of metabolism and decreased
proliferation and growth rates.
◉ Which of the following describes a dental implant that is placed
on the surface of the bone beneath the periosteum? Answer:
Subperiosteal
RATIONALE: A subperiosteal implant is placed on the surface of the
bone beneath the periosteum. Periosseous is not a term associated
with a type of dental implant. An endosseous implant is placed into
the alveolar bone whereas a transosteal implant is placed through
the alveolar bone.
, ◉ Studies of the natural history of periodontal disease have shown
which of the following to be TRUE? Answer: Periodontal therapy and
oral self-care will slow the rate of attachment loss in periodontitis.
RATIONALE: In studies of Sri Lanka tea workers, comparison of
untreated groups with regular dental care attendees from Norway
documented that periodontal therapy and self-care slow the rate of
clinical attachment loss (0.3 and 0.1 mm, respectively). Because
plaque and calculus are common in treated and untreated clients,
incidence of periodontitis is not affected by the amount these
accretions. Regarding patterns of disease progression, gingivitis will
not necessarily progress to periodontitis, nor does untreated
periodontal disease rapidly progress.
◉ Acidic agents, such as acidulated phosphate fluoride (APF) gels
and foams, can inadvertently dissolve ceramic phases on all of the
following surfaces EXCEPT one. Which one is the EXCEPTION?
Answer: Pit and fissure sealants
RATIONALE: Inadvertent dissolution of a ceramic phase is not a
concern with pit and fissure sealants because sealants do not
contain a ceramic phase that is vulnerable to dissolution. When a
client's treatment plan includes an acidulated phosphate fluoride gel
or foam, the dental hygienist must first assure that damage from the
low pH (acidity) of the solution will not damage any existing dental
restorations. Hybrid composites have glass fillers that can be
dissolved by APF. Porcelain fused-to-metal (PFM) restorations can
2026 QUESTIONS WITH SOLUTIONS GRADED
A+
◉ During the intraoral examination, a translucent-to-whitish
irregular film on the buccal mucosa is noted. The film is not
removable with gauze. Which of the following conditions is MOST
likely present? Answer: Hyperkeratinization
RATIONALE: Hyperkeratinization can result from constant low-
grade irritations such as cheek biting, which causes an abnormal
layer of keratin to develop. The client needs to be questioned
regarding parafunctional oral habits. Hyperplasia is an increase in
the number of cells whereas linea alba presents as a whitish,
horizontal, elevated line on the buccal mucosa at the height of the
occlusal plane. Also whitish in appearance, leukoplakia is
characterized as white patches that sometimes appear fissured, may
cause discomfort, cannot be scraped off and are considered
precancerous.
◉ When comparing permanent and primary molars, which of the
following statements is TRUE? Answer: Primary molars have larger
pulp chambers.
,RATIONALE: The pulp chambers of primary molars are larger than
those of the permanent molars. Second primary molars, not first
primary molars, have anatomy similar to that of the first permanent
molars. Primary molars have the same number of roots as
permanent molars; note that neither primary molars nor permanent
molars are classified as succedaneous teeth. A succedaneous tooth is
a permanent tooth that replaces a primary tooth. Thus, permanent
incisors are succedaneous, but permanent molars are not. The root
trunks of primary molars are very short in comparison with those of
permanent molars
◉ John Jeffry, a 45-year-old man, calls the dental office to request an
appointment for an oral examination. After discovering that he has
cerebral palsy, the office manager tells Mr. Jeffry that he cannot be
treated in the office due to his condition. Which of the following
BEST describes the behavior being demonstrated by the office
manager? Answer: This behavior is an example of discrimination
according to the Americans with Disabilities Act.
RATIONALE: This illegal behavior is an example of discrimination
according to the Americans with Disabilities Act (ADA). Based upon
the ADA, dental practices can neither refuse treatment based on a
client's disability nor can they prescreen clients to determine
whether they will provide care. Although the Equal Rights
Amendment affords important protection to all citizens, it has no
bearing on the provision of dental treatment.
,◉ Which of the following correctly ranks the tissues in order of
MOST sensitive to LEAST sensitive to ionizing radiation? Answer:
Reproductive, lymphatic, endocrine, digestive, nervous
RATIONALE: In general, younger cells with a high rate of
metabolism, an increased proliferation and growth rate, and a
decrease in specialization are more susceptible to radiation-induced
biologic changes. Therefore, reproductive organs represent tissue
with cells that are most radiosensitive, whereas the nervous system
is composed of cells considered to be the most radioresistant. In
descending order of radiosensitivity are lymphatic, endocrine, and
digestive tissues. An important concept, tissues that are less
sensitive to radiation-induced biological changes will be more
specialized, have lower rates of metabolism and decreased
proliferation and growth rates.
◉ Which of the following describes a dental implant that is placed
on the surface of the bone beneath the periosteum? Answer:
Subperiosteal
RATIONALE: A subperiosteal implant is placed on the surface of the
bone beneath the periosteum. Periosseous is not a term associated
with a type of dental implant. An endosseous implant is placed into
the alveolar bone whereas a transosteal implant is placed through
the alveolar bone.
, ◉ Studies of the natural history of periodontal disease have shown
which of the following to be TRUE? Answer: Periodontal therapy and
oral self-care will slow the rate of attachment loss in periodontitis.
RATIONALE: In studies of Sri Lanka tea workers, comparison of
untreated groups with regular dental care attendees from Norway
documented that periodontal therapy and self-care slow the rate of
clinical attachment loss (0.3 and 0.1 mm, respectively). Because
plaque and calculus are common in treated and untreated clients,
incidence of periodontitis is not affected by the amount these
accretions. Regarding patterns of disease progression, gingivitis will
not necessarily progress to periodontitis, nor does untreated
periodontal disease rapidly progress.
◉ Acidic agents, such as acidulated phosphate fluoride (APF) gels
and foams, can inadvertently dissolve ceramic phases on all of the
following surfaces EXCEPT one. Which one is the EXCEPTION?
Answer: Pit and fissure sealants
RATIONALE: Inadvertent dissolution of a ceramic phase is not a
concern with pit and fissure sealants because sealants do not
contain a ceramic phase that is vulnerable to dissolution. When a
client's treatment plan includes an acidulated phosphate fluoride gel
or foam, the dental hygienist must first assure that damage from the
low pH (acidity) of the solution will not damage any existing dental
restorations. Hybrid composites have glass fillers that can be
dissolved by APF. Porcelain fused-to-metal (PFM) restorations can
