1
IMULATED NATIONAL BOARD DENTAL HYGIENE EXAM LATEST
VERSION -2025/2026- 100+ Q AND ANS ALL THE BEST
Which of the following describes a dental implant that is placed on the surface of
the bone beneath the periosteum?
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.
When comparing permanent and primary molars, which of the following
statements is TRUE?
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
, 2
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?
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?
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.
Studies of the natural history of periodontal disease have shown which of the
following to be TRUE?
Periodontal therapy and oral self-care will slow the rate of attachment loss in
periodontitis.
, 3
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?
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 be partially dissolved by APF as
can CAD/CAM ceramics which are etched during the bonding procedures by
hydrofluoric acid. Also vulnerable to dissolution by APF are porcelain veneers.
The eruption sequence for maxillary permanent teeth is: central incisors, lateral
incisors, first molars, canines, first premolars
In general, maxillary permanent teeth erupt prior to mandibular permanent teeth.
Both statements are FALSE.
, 4
RATIONALE: The eruption sequence for maxillary permanent teeth is first molars
(age 6 to 7); central incisors (age 7 to 8); lateral incisors (age 8 to 9); first
premolars (age 10 to 11); canines (age 11 to 12). In general, the mandibular
permanent (as well as deciduous) teeth erupt prior to their maxillary
counterparts.
Congenital heart disease is associated with anomalies of the heart structure.
Anomalies of the heart structure occur in utero during weeks 15 through 20.
The first statement is TRUE, the second is FALSE.
RATIONALE: Congenital heart disease is associated with anomalies of the heart
structure, which occur in the first 9 weeks in utero.
The surfaces used to determine the terminus or terminal plane of the primary
dentition is the
distal surface of a mandibular second primary molar.
RATIONALE: Distal surfaces of second primary molars are considered to be end
vertical planes or termini of the primary dentition. A terminus refers to the end of
a structure; neither the first primary molar nor its mesial surface is the endpoint
of a primary dentition. Similarly, the distal surface of a mandibular first primary
molar is not the end point of a primary dentition. In the same logic pattern, the
mesial surface of a second primary molar is not the termination of a primary
dentition.
Plaque-induced gingivitis will always progress to chronic periodontitis if left
untreated.
IMULATED NATIONAL BOARD DENTAL HYGIENE EXAM LATEST
VERSION -2025/2026- 100+ Q AND ANS ALL THE BEST
Which of the following describes a dental implant that is placed on the surface of
the bone beneath the periosteum?
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.
When comparing permanent and primary molars, which of the following
statements is TRUE?
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
, 2
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?
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?
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.
Studies of the natural history of periodontal disease have shown which of the
following to be TRUE?
Periodontal therapy and oral self-care will slow the rate of attachment loss in
periodontitis.
, 3
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?
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 be partially dissolved by APF as
can CAD/CAM ceramics which are etched during the bonding procedures by
hydrofluoric acid. Also vulnerable to dissolution by APF are porcelain veneers.
The eruption sequence for maxillary permanent teeth is: central incisors, lateral
incisors, first molars, canines, first premolars
In general, maxillary permanent teeth erupt prior to mandibular permanent teeth.
Both statements are FALSE.
, 4
RATIONALE: The eruption sequence for maxillary permanent teeth is first molars
(age 6 to 7); central incisors (age 7 to 8); lateral incisors (age 8 to 9); first
premolars (age 10 to 11); canines (age 11 to 12). In general, the mandibular
permanent (as well as deciduous) teeth erupt prior to their maxillary
counterparts.
Congenital heart disease is associated with anomalies of the heart structure.
Anomalies of the heart structure occur in utero during weeks 15 through 20.
The first statement is TRUE, the second is FALSE.
RATIONALE: Congenital heart disease is associated with anomalies of the heart
structure, which occur in the first 9 weeks in utero.
The surfaces used to determine the terminus or terminal plane of the primary
dentition is the
distal surface of a mandibular second primary molar.
RATIONALE: Distal surfaces of second primary molars are considered to be end
vertical planes or termini of the primary dentition. A terminus refers to the end of
a structure; neither the first primary molar nor its mesial surface is the endpoint
of a primary dentition. Similarly, the distal surface of a mandibular first primary
molar is not the end point of a primary dentition. In the same logic pattern, the
mesial surface of a second primary molar is not the termination of a primary
dentition.
Plaque-induced gingivitis will always progress to chronic periodontitis if left
untreated.
