- Oral Surgery, Oral Medicine, Oral Pathology, Oral

Evaluation of the pterygoid hamulus morphology using cone
beam computed tomography
Kaan Orhan, DDS, PhD,a,b Bayram U. Sakul, PhD,c Ulas Oz, DDS, PhD,d and
Burak Bilecenoglu, DDS, PhD,e Ankara and Mersin, Turkey
UNIVERSITY OF ANKARA, NEAR EAST UNIVERSITY, ANKARA UNIVERSITY, AND UFUK UNIVERSITY
Objective. This study consists of anatomic research of the pterygoid hamulus (PH) using 3D cone beam computed
tomography (CBCT) images reconstructed from a volumetric rendering program.
Study design. Three hundred ninety-six sides in the CBCT scans of 198 (115 men and 83 women) patients were
retrospectively analyzed. DICOM data of the patients were transferred to a surface-rendering software so as to generate
3D hard tissue surface representations of PHs. The width, length, angle, and the distance between posterior nasal
spine and tip of the PH were measured. In addition, the inclinations of PHs were also evaluated in sagittal and coronal
planes of the 3D images. Pearson ␹2 and Student t test were performed for statistical analysis among age, localization,
and measurements (P ⬍ .05).
Results. The mean PH measurements of left and right sides were 1.72 (SD 0.94) and 1.87 (SD 1.17)-mm width, and
the lengths were 5.48 (AD 1.94), and 5.40 (SD 2.0) mm, respectively, with no significant difference (P ⬎ .05). All PHs
were inclined toward the lateral side in the coronal plane, whereas PHs tended to incline toward the posterior rather
than anterior in the sagittal plane (⬃78%). The results showed no statistically significant differences among age,
localization, and measurements of PHs (P ⬎ .05).
Conclusions. Knowledge about the morphology of these structures is helpful for the interpretation of imaging and
provides valuable information in the differential diagnosis of untraceable pains in the oral cavity and pharynx. Because
of potential problems owing to PH morphology and elongation, oral and maxillofacial radiologists should assess the
radiographic images thoroughly. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011;112:e48-e55)
A broad definition of pterygoid hamulus (PH) is a
hooklike projection at the inferior end of each medial
plate of the pterygoid process. The medial pterygoid
plate of the sphenoid bone curves laterally at its lower
extremity into a hooklike process, the PH, around
which the tendon of the tensor veli palatini (TVP)
muscle glides. Although the PH is, because of its bizarre shape, a striking feature of the skull base, it is still
an unexplored region on the anatomical map.1,2 Only a
few studies have been conducted on the morphology of
PH1-4; however, because of its close relationship to the
a
Associate Professor, Department of Oral, Tooth and Jaw Radiology,
University of Ankara, Faculty of Dentistry, Ankara, Turkey.
b
Associate Professor, Department of Oral, Tooth and Jaw Radiology,
Near East University, Faculty of Dentistry, Mersin, Turkey.
c
Professor, Department of Anatomy, Ankara University, Faculty of
Dentistry, Ankara, Turkey.
d
Assistant Professor, Department of Orthodontics, Near East University, Faculty of Dentistry, Mersin, Turkey.
e
Assistant Professor, Department of Anatomy, Ufuk University, Faculty of Medicine, Ankara, Turkey.
Received for publication Oct 16, 2010; returned for revision Feb 17,
2011; accepted for publication Feb 22, 2011.
1079-2104/$ - see front matter
© 2011 Mosby, Inc. All rights reserved.
doi:10.1016/j.tripleo.2011.02.038
e48
maxilla and oropharynx, it is of interest to all disciplines that are involved with this region.1
The position, length, and inclination of PHs are of
great importance for the function of several muscles:
tensor veli palatini, palatopharyngeus, and upper part of
the upper pharyngeal constrictor, pars pterygopharyngea. These muscles contribute to the separation of the
oral from the nasal cavity during sucking and swallowing during growth and development and into adulthood.2,3
Elongation of PH was also associated with a rare
syndrome of PH that shows various and complex symptoms in the palatal and pharyngeal regions and also
causes pain and discomfort especially during swallowing. The term pterygoid hamulus syndrome was first
used to describe a pain in the palatal and pharyngeal
regions caused by an abnormally shaped PH by Hjørting-Hansen et al.5,6 in 1987 with about 40 cases reported in the literature.4-15
Several studies were conducted on the position and
morphology of PH in different populations. According
to those studies, the length of the PH was found to be
within the range of 4.9 to 7.2 mm.1-4,10 Putz and
Kroyer1 also reported the sagittal and transverse diameter of PH as 1.4 mm and 2.3 mm, respectively,
whereas Sasaki et al.10 also reported an elongated PH of
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Orhan et al. e49
Fig. 1. Panoramic radiography of the patient showing no abnormality except flattening of left TMJ condyle.
13 mm. Recently, it was found that the length increased
in adult age and then decreased significantly again in
the elderly population. Moreover, all studies reported
that the positions of PHs are inclined laterally in the
coronal plane.1-2
This information is important especially in tracing an
unusual pain in the soft palate and pharyngeal region.
Such a symptom in that area may be forming a complex
that can include hearing disorders, difficulties in swallowing, headache, pain and clicking in the temporomandibular joints (TMJs), uncontrolled movements of
the facial muscles, impacted teeth, trigeminal and glossopharyngeal neuralgia, stylo-hyoid ligament calcification, stylo-mandibular ligament inflammation, tumors,
cysts, herpes simplex, infection, otitis media, and so
forth; thus, consideration of the PH as a pain-inducing
factor should be included in the diagnosis.4,8,11 Therefore, it is important to know the average length, shape,
and morphology of PHs for the population that guided
us to conduct this research.
The detection of this area can be achieved by radiography (cephalometric radiography, submentovertex,
Waters view, and so forth); however, identification of
these structures by conventional radiography is exceedingly difficult because of superimposition and distortion. Today, computed tomography (CT) can be performed in axial and coronal planes with 3-dimensional
(3D) views for diagnosis and treatment.8 The 3D CT
avoids superimposition and problems owing to magnification and offers visualization of the craniofacial
structures with more precision than the 2D conventional methods.16-19
Despite various studies that were conducted on
shape, length, and position of the PH, the anatomical
relations of PH and the surrounding structures are
rarely investigated.1-4 Moreover, no studies were found
on cone beam computed tomography (CBCT) imaging
with generated 3D skull representations using a surface-rendering program to identify and investigate PH.
Thus, this study consists of anatomic research of PH
using 3D CBCT images reconstructed form a volumetric rendering program.
MATERIAL AND METHODS
In the case that guided us to this research, a 26-yearold female was referred to our outpatient clinic because
of painful and burning sensations in the soft palate and
pharynx of 9 months’ duration. The patient’s history
revealed that the symptoms started after traumatic removal of the right maxillary third molar. For this pain,
she stated that she was referred to 10 to 15 different
consultants, including ear, nose, and throat and maxillofacial surgeons, and various diagnoses were made,
such as temporomandibular disorder (TMD) and glossopharyngeal neuralgia. The patient received nonsteroidal anti-inflammatory drugs and also an occlusal splint
for TMD. However, the painful sensation was not resolved during the 9 months.
Initial panoramic radiography of the patient showed
neither a carious lesion nor any root fragment in the
extraction site (Fig. 1) with slight degeneration on the
left TMJ condyle. Intraorally, pain and a firm swelling
were noted in palpation of the region. A decision was
made to perform CBCT to obtain a more precise view
of the region. Axial CBCT scan did not demonstrate
any abnormality; however, coronal sections showed
elongated PH in the right side. The 3D reconstructed
CBCT images also showed an elongated PH (9.7 mm in
length) with a sickle shape (Fig. 2). Infiltration of local
anesthesia to the PH subsided pain; however, the symptoms returned after the anesthetic was metabolized. A
diagnosis of hamular pain was made. The patient was
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Fig. 2. a, Axial CBCT scan showed no abnormality, whereas in b and c, coronal CBCT images showed elongated PH on the right
side (arrows) with a normal PH on the left side (arrowhead). d, e, 3D reconstructed CBCT images also showed elongated PH (9.7
mm in length) with a sickle shape (arrow).
referred for surgery of elongated PH. Following this
case, we decided to conduct further research regarding
PH morphology in our population.
For this purpose, 396 sides of 198 subjects (115 men
and 83 women) ranging in age from 22 to 75 years
(mean: 35.54) who had craniofacial CBCT scans were
retrospectively investigated. CBCT images were taken
for various purposes, such as preimplant imaging, paranasal sinus examinations, or orthodontic purposes. The
study’s protocol was carried out according to the principles described in the Declaration of Helsinki, including all amendments and revisions. Only the investigators had access to the collected data. The institutional
review board of the faculty reviewed and approved
informed consent forms. There was no preference about
gender regarding sample choice, however only Turkish
patients were included in the study. Only high-quality
scans were included. Images of low quality, such as
scattering or insufficient accuracy of bony borders were
excluded.
CBCT scans were made with a Newtom 3G (Quantitative Radiology s.r.l., Verona, Italy). The imaging
protocol used a 9-inch field of view to include the
mandibular and maxillary anatomy. X-ray parameters
of kV and ma are automatically determined from scout
views by the NewTom 3G. Depending on the size of
the patient and the extent of beam attenuation, a variation in exposure of up to 40% was possible.
The axial slice thickness was 0.3 mm, and the voxels
were isotropic. The axial images were exported as a
512 ⫻ 512 matrix in DICOM file format and then were
imported in Maxilim software version 2.3.0 (Medicim,
Mechelen, Belgium). All constructions and measurements were performed on a 21.3-inch flat-panel color
active matrix TFT medical display monitor (Nio Color
3MP, Barco, Belgium) with a resolution of 2048 ⫻
1536 at 76 Hz and 0.2115-mm dot pitch operated at 10
b. A consultant experienced in 3D imaging made highquality 3D hard tissue surface representations computed from the patients’ CBCT data set in several
stages similar to previous studies20-22 and examined all
images.
First, the bone and soft tissue surfaces were segmented by applying a threshold on the acquired image
volume of radiographic densities. An attempt was made
to reduce noise without reducing actual osseous anatomy. The skulls were rendered as high-quality 3D hard
tissue surface representations that were computed from
the patients’ CBCT data set. The axial, sagittal, and
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Orhan et al. e51
using rotation and translation of the rendered images.
Landmarks were identified by using a cursor-driven
pointer. The width and the length of the PH together
with the distance and the angles between posterior nasal
spine (PNS) and tip of the PH were measured (Fig. 3,
a, b, and c). To standardize the measurements, reference points were chosen. The length measurements
were taken from the junction of medial pterygoid plate
and PH through the tip, similar to Putz and Kroyer’s
study.1 First a line was drawn from the junction of
medial pterygoid plate and PH parallel to the horizontal
plane. Following the identification of the midpoint of
this line, the length was measured starting from this
point to the tip of the PH. The width of the PH was
measured as the distance between the most prominence
points of the PH in the coronal plane (Fig. 3, c).
In addition, the inclinations of PHs were evaluated in
sagittal and coronal planes of the 3D images. The
average degrees of inclinations in the sagittal and coronal planes were also calculated by means of the software according to horizontal plane following Putz and
Kroyer’s study1 (Fig. 4). The inclinations in the sagittal
plane were also classified visually as anterior and posterior (Fig. 5), whereas inclinations in the coronal plane
were classified as lateral or medial. All measurements
were done 3 times by the same observer and the mean
of these measurements were noted for analysis. The
observer also performed the study 2 times with an
interval of 2 weeks so as to detect intraobserver variability.
Statistical analyses were carried out using the SPSS
12.0.1 (SPSS, Chicago, IL) software program. To assess intraobserver reliability, Wilcoxon matched-pairs
signed-ranks test was used for repeated measurements
of the observer. Pearson ␹2 and Student t test were
performed for statistical analysis among age, localization, and measurements (P ⬍ .05).
Fig. 3. a, b, Figure showing the measurements performed in
the study that were made on a generated 3D image from
volumetric rendering software with superimposed coronal
slices over reconstructed 3D image taken from CBCT data. c,
Cropped image showing the length and width measurement in
detail. w, width; l, length.
coronal CT radiographic slices were also superimposed
over reconstructed 3D images (Fig. 3).
Measurements of 3D images were located and
marked on the 3D surface-rendered volumetric image
RESULTS
Repeated measurement of CBCTs indicated no significant intraobserver difference (P ⬎ .05). Intraobserver consistency was rated at 95% between 2 measurements. A total of 396 left and right sides of PHs
were measured in 198 3D CBCT images. The findings
are presented in Table I. The mean measurements of
both left and right sides were 1.72 (SD 0.94) and 1.87
(SD 1.17)-mm width, respectively whereas the lengths
were 5.48 (SD 1.94) and 5.40 (SD 2.0) mm, respectively without any significant difference (P ⬎ .05).
There were also no statistically significant differences
between left and right measurements between posterior
nasal spine and tip of the PH of sides (P ⬎ .05).
In the coronal plane, it was found that all PHs were
inclined toward the lateral side (Fig. 3). However, in
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Orhan et al.
Fig. 4. a, 3D images showing angle and orientation of PH in the coronal plane, b, in the sagittal plane, and c, the angle between
the posterior nasal spine and tip of the PH. HoP indicates horizontal plane.
Fig. 5. 3D reconstructed images showing a, anterior inclination and b, posterior inclination of PH (arrows).
Table I. Measurements of PH (mm) and standard deviations (SD) together with inclination of PH in coronal and
sagittal planes
Left
Measurements (mean ⫾ SD)
Width of the PH in coronal plane
Length of the PH
Posterior nasal spine to tip of PH
The average inclination in
coronal plane
The average inclination in
sagittal plane
Number of inclinations of PH in
coronal plane
Total
(mean ⫾ SD)
Male
(mean ⫾ SD)
Female
(mean ⫾ SD)
Total
(mean ⫾ SD)
Male
(mean ⫾ SD)
Female
(mean ⫾ SD)
1.72 ⫾ 0.94
5.48 ⫾ 1.94
21.35 ⫾ 2.45
52.5° ⫾ 2.57°
1.73 ⫾ 0.83
5.49 ⫾ 1.95
21.46 ⫾ 2.47
53.2° ⫾ 2.18°
1.70 ⫾ 1.07
5.45 ⫾ 1.91
21.19 ⫾ 2.42
51.9° ⫾ 1.96°
1.87 ⫾ 1.17
5.40 ⫾ 2.00
21.18 ⫾ 3.09
53.9° ⫾ 2.01°
1.93 ⫾ 1.44
5.38 ⫾ 1.99
21.3 ⫾ 3.35
54.1° ⫾ 2.33°
1.79 ⫾ 0.60
5.43 ⫾ 2.01
21.02 ⫾ 2.70
53.8° ⫾ 2.16°
82.6° ⫾ 3.08°
82.8° ⫾ 3.19°
82.4° ⫾ 2.90°
81.9° ⫾ 3.25°
81.8° ⫾ 3.40°
82.0° ⫾ 2.99°
83
198
0
0
22 (26.5%)
45 (22.7%)
61 (73.5%)
153 (77.3%)
198
0
Number of inclinations of PH in
sagittal plane
Right
43 (21.7%)
155 (78.3%)
Lateral
115
Medial
0
Anterior
21 (18.3%)
Posterior
94 (81.7%)
Lateral
115
Medial
0
Anterior
28 (24.3%)
Posterior
87 (75.7%)
83
0
17 (20.5%)
66 (79.5%)
PH, pterygoid hamulus.
the sagittal plane, 43 (21.7%) PHs were inclined
toward the anterior whereas 155 (78.3%) PHs tended
to posterior on the left side. Similarly, on the right
side, 45 (22.7%) PHs were inclined toward the anterior, whereas 153 (77.3%) PHs tended to the posterior (Fig. 5).
The average inclination in the sagittal plane and in
the coronal plane showed no statistically significant
difference (P ⬎ .05) (Table I). The angles between
posterior nasal spine and tip of the PH were also measured. The average degree for the left was 33.4° (SD
2.34) and 34.3° (SD 2.18) for right. Overall results also
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Table II. Measurements of PH (mm) and standard
deviations (SD) according to age
Measurements
(mean ⫾ SD)
Width of the PH in
coronal plane
Length of the PH
Posterior nasal spine to
tip of PH
The average inclination in
coronal plane
The average inclination in
sagittal plane
Number of inclinations of
PH in coronal plane
Number of inclinations of
PH in sagittal plane
22-55 y
⬎55 y
Total (mean ⫾ SD) Total (mean ⫾ SD)
1.85 ⫾ 0.88
1.73 ⫾ 1.07
6.38 ⫾ 1.93
21.73 ⫾ 2.54
4.50 ⫾ 1.72
20.8 ⫾ 2.85
53.9° ⫾ 2.18°
52.5° ⫾ 2.17°
82.8° ⫾ 2.99°
81.7° ⫾ 3.05°
Lateral
166
Medial
0
Anterior
39
Posterior
127
Lateral
32
Medial
0
Anterior
4
Posterior
28
showed no statistically significant differences among
gender, localization, and measurements of PHs (P ⬎
.05).
As a further evaluation, we divided the study group
into 2 age groups, 22 to 55 and older than 55 years, so
as to detect any differences according to age group.
Table II shows the data according to age group. The
length of PH differed among the age groups. The patient group older than 55 had shorter PH length than the
22- to 55-year-olds (P ⫽ .054) (Table II). No further
statistically significant difference was found among age
and all measurements (P ⬎ .05).
DISCUSSION
Anatomically, the PH and the edge of the medial
pterygoid plate immediately superior to the PH, give
rise to the origin of the superior constrictor muscle of
the pharynx. The palate pharyngeus muscle originates
in layers from the PHs, as well as from the border of the
hard palate, and from fibers of the levator veli palatine
muscle (LVP). It is generally stated that the lowest and
most anterior fibers of LVP arise from the base of the
pterygoid process and reach up to and a little beyond
the base of the PH. In addition, TVP originating from
the scaphoid fossa, the spine of palatal aponeurosis,
and the lateral wall of the cartilaginous auditory tube
winds its tendon around the PH in a groove with a
synovial bursa between the tendon and the bone, inserts
soft palate. The separation of the oral from the nasal
cavity is accomplished by the elevation of soft palate
with constriction of these muscles.3,8,22,23 As the tendon of the TVP winds around the PH, a synovial bursa
is situated between the tendon and the bone. This bursa
within the sulcus hamulus is responsible for the gliding
of the tendon. It reduces friction caused by movement
of the tendon of the TVP muscle around the PH.
The position, inclination, and especially the length of
PHs are of great importance for the function of the
muscles that are located here. When these muscles
contract, the nasal and oral cavities separate from each
other during swallowing and sucking. This separation is
accomplished by the evaluation of soft palate following
LVP contraction and Tubar part of TVP for stretching
the palatal aponeurosis.2,7,8 TVP also produces tension
and elevation of soft palate, which the Tubar part is
fixed to the hamulus. The position and morphology of
PH are closely related to TVP function, which directly
affects the width of the hard plate during swallowing.
The inclination of the PH is also responsible for better
tension of palatal apounerosis.2 Krmpotić-Nemanić et
al.2 pointed out that if the hamulus remains short as in
newborns, the surrounding muscles do not have firm
support, which leads to uncontrolled narrowing of the
upper pharynx, thus causing snoring and sleep apnea.
Besides, the elongated PH can also be the reason for
pain and discomfort in the soft palate and pharynx.10 Such
cases have been previously reported. Gores15 was the first
to report the presence of pain caused by a long PH. The
term pterygoid hamulus syndrome was then used to describe a pain in the palatal and pharyngeal regions with
about 40 cases reported in the literature.4-14
There is no consensus for the etiology of this syndrome.
Previously, several etiologic factors stated bursitis of TVP
or an osteophyte,4,9-12,14 elongation of PH,4,10 or consistent minimal trauma to the overlying structure.13 The
trauma from swallowing a large bolus of food or from an
overextended denture, anesthesia intubations, trauma during tooth brushing, bulimic patients, and “fellatio” in child
abuse seem to be the cause of this syndrome.10,11 In our
case, the patient had her third molar extracted and the
symptoms started after this operation.
Patients suffering from this syndrome have clinical
signs, including pain and sensation of strangeness,
burning and swelling of the hard/soft palate, elevated
noise sensitivity, dysphagia, dysfunction of muscles,
and difficulty in swallowing. Clinically, the PH region
usually appears erythematous; sometimes the PH can
be palpated as firm swelling or recognized as an enlargement under the mucosa of the soft palate.9-11 Further, the PH may have tenderness to palpation, which
will be eliminated after anesthetic infiltration of the
area. In our case, no erythematous appearance was
seen; however, a firm swelling was noted and pain
subsided after anesthetic infiltration.
The differential diagnosis of pain in the hard/soft
palate and pharynx should include tumors, cysts, infections, foreign bodies, elongated styloid syndrome, third
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Orhan et al.
molar eruption, TMJ diseases, muscular dysfunction,
and also elongated PH.4,10,11
Several studies were conducted on the morphology
of PH in different populations. Eyrich et al.4 found the
mean length of the left hamulus to be 5 mm and
the right to be 4.9 mm. Putz and Kroyer1 reported the
average length to be 7.2 mm and the sagittal and
transverse diameter to be 1.4 mm and 2.3 mm, respectively. Sasaki et al.10 also reported an average PH
length of 6.8 mm (SD 1.4 mm). Our results showed the
mean length of PHs for left and right sides were 5.48
(SD 1.94) and 5.40 (SD 2.0) mm, respectively which is
similar to other studies.1,4,10 There was no significant
difference according to gender and location. Sasaki et
al.10 reported an elongated PH case of 13 mm. Our
longest PH case was 10.9 mm in a male patient.
Recently Krmpotić-Nemanić et al.2 conducted an
extensive study on PH. They investigated the PH
among 3 age groups: children (0-9), adults (21-59), and
elderly (60-100). They found that children had the
shortest PH length, on average 3.6 mm. The length
increased in adults (6.9 mm) and then decreased significantly again to 5.0 mm in the elderly group. They
also found no statistical difference for gender and for
left and right sides.
Although no statistically significant difference was
observed between the age groups, the P value was .054.
From a numerical point of view, it can be concluded
that older patients had shorter PH length than the
younger patients. This is in line with KrmpotićNemanić et al.’s2 study, but does not coincide with Putz
and Kroyer’s1 study, which reported that the PH increases in length to the beginning of adulthood, and
thereafter remains unchanged throughout life.
There was only one study regarding the width and
the inclination of the PH.1 Putz and Kroyer1 measured
the sagittal diameter of PH as 1.4 mm, which is consistent with our width (sagittal diameter) measurements: 1.72 (SD 0.94) and 1.87 (SD 1.17) mm for left
and right, respectively. The inclinations in their study
were 75° in the sagittal plane and 58° in the coronal
plane, which is also similar to our results (Table II).
Each hamulus in this study was inclined laterally, as in
previous studies.1-2 The results showed no statistically
significant differences among gender, localization, and
measurements of PHs (P ⬎ .05).
The elongated PH can be responsible for atypical
pain in the soft palate and pharynx region. Radiographs
of the PH and pterygomaxillary region should be obtained for the findings of osteophytes or hamular fracture or for any other abnormality. The detection of this
area can be achieved by radiography (cephalometric
radiography, Submentovertex, Waters view, conventional tomography). However, identification of these
structures by conventional radiography is exceedingly
difficult because of superimposition and distortion. Today, CT can be performed in axial and coronal planes
with 3D views for diagnosis and treatment of this
region.7-8,24 The 3D CT avoids the superimposition and
problems owing to magnification and offers visualization
of the craniofacial structures with more precision than the
2D conventional methods.17-19,25 Despite these advantages, the effective dose of CT is much higher than the
conventional radiographs and also expensive procedures
and scanners are not easily accessible.19,26,27
In the past decade, CBCT was proposed for maxillocraniofacial imaging.28-31 The advantages of this imaging modality are the following: lower radiation dose
than traditional CT, the possibility of individualized
overlap-free reconstructions, and DICOM data can be
imported and exported for other applications.28 Dental
CBCT can be recommended as a dose-sparing technique compared with alternative standard medical CT
scans for common oral and maxillofacial radiographic
imaging tasks. Effective dose (ICRP 2007) from a
standard dental protocol scan with the traditional CT
was from 1.5 to 12.3 times greater than comparable
medium field of view dental CBCT scans.32 It was also
stated that effective dose and dose to the main portions
of the head and neck were higher for traditional CT
than for CBCT. Image quality of CBCT was judged to
be equivalent to that of traditional CT for visualizing
the maxillofacial structures.33-37
From the radiation point of view, CBCT examinations can be used instead of CT to evaluate this region.
When 3D imaging is required to visualize anatomic
structures, such as processes of sphenoid bone, hard/
soft palate, and oropharynx, CBCT should be preferred
over a CT image.
CONCLUSIONS
Knowledge about the morphology of these structures
is helpful for the interpretation of imaging and provides
valuable information in the differential diagnosis of
untraceable pains in the oral cavity and pharynx. Because of potential problems owing to PH morphology
and elongation, oral and maxillofacial radiologists
should assess the radiographic images thoroughly. Similar studies will provide useful information to better
understand the anatomy and diseases regarding the PH.
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Reprint requests:
Kaan Orhan, DDS, PhD
Department of Oral, Teeth and Jaw Radiology
University of Ankara
Faculty of Dentistry
Ankara, Turkey
[email protected]