Clinical Review of Oral and Maxillofacial Surgery

445 Pages·2007·14.425 MB·English

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Clinical Review of Oral and Maxillofacial Surgery 978-0-323-04574-2
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Knowledge and best practice in this fi eld are constantly changing. As new research and experience
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FM-A04574.indd iv 6/27/2007 2:47:11 PM
To my wife Nooshin, whose love and support gave me the energy and confi dence to
complete this project, and to my son, Shaheen, whose peaceful smile while falling
asleep inspired me as I wrote many sections by his bedside.
To my parents, Parviz and Ladan, who have supported me for many years towards
my academic and professional goals at the expense of being away from them.
To my brother, Homayoun, who at present and in my youth, has been my support
and source of intellectual stimulation.
To my mentors, Dr. Robert A. Bays, Dr. Sam E. Farish, Dr. Eric J. Dierks, Dr.
Bryce E. Potter, and Dr. Leon A. Assael, who through their teachings provided me
the experience and tools to complete this project.
To all patients, students, and residents of oral and maxillofacial surgery.
Shahrokh C. Bagheri
To my Lord and Savior, who makes all things possible.
To my wife, Sunny, whose smile and love gives me the strength and motivation to
continue in my professional, academic, and personal endeavors.
To my parents, Hae Sung and Kum Sook Jo, who taught me to pursue excellence in
all things and who have tirelessly supported me during my training.
To my sister, Jenny, whose academic achievements motivated me to follow in her
footsteps.
To my mentors Dr. Robert A. Bays, Dr. Vincent J. Perciaccante, Dr. Sam E. Farish,
Dr. Steven M. Roser, and Dr. John E. Griffi n, who gave me the training, experience,
and motivation to fi nish this project.
To my fellow residents who were in the trenches with me during residency training:
Piyush, Shahrokh, Nizar, Jennifer, Donnie, Nader, Marty, Harry, John, Mehran,
Hussein, Tony, Xin, Boris, Brenda, Cang, Fernando, Deepak, Sam, Bruce, Danielle,
Abtin, Jaspal, and Bill.
Chris Jo
FM-A04574.indd v 6/27/2007 2:47:12 PM
Chapter Editors and Contributors
Chapter Editors Bruce Anderson, HBSc, DDS
Resident
Shahrokh C. Bagheri, DMD, MD
Department of Surgery
Clinical Assistant Professor of Oral and Maxillofacial
Division of Oral and Maxillofacial Surgery
Surgery
Emory University
Emory University School of Medicine
School of Medicine
Division of Oral and Maxillofacial Surgery;
Atlanta, Georgia
Private Practice
Atlanta Oral and Facial Surgery
Michael L. Beckley, DDS
Atlanta, Georgia
Department of Oral and Maxillofacial Surgery
University of the Pacifi c
Deepak Kademani, DMD, MD, FACS
School of Dentistry
Assistant Professor of Surgery
San Francisco, California
Consultant, Oral and Maxillofacial Surgery
Department of Oral and Maxillofacial Surgery
R. Bryan Bell, DDS, MD, FACS
Mayo Clinic
Clinical Assistant Professor
College of Medicine
Department of Oral and Maxillofacial Surgery
Rochester, Minnesota
Oregon Health and Science University;
Attending Surgeon
Husain Ali Khan, MD, DMD
Oral and Maxillofacial Surgery Service
Private Practice
Legacy Emanuel Hospital and Health Center
Atlanta Oral and Facial Surgery
Portland, Oregon
Cartersville, Georgia
Samuel L. Bobek, DMD
Chris Jo, DMD
Resident
Clinical Assistant Professor of Oral and Maxillofacial
Department of Oral and Maxillofacial Surgery
Surgery
Oregon Health and Science University
Emory University School of Medicine
Portland, Oregon
Division of Oral and Maxillofacial Surgery;
Private Practice
Gary F. Bouloux MD, DDS, MDSc, FRACDS,
Atlanta Oral and Facial Surgery
FRACDS(OMD)
Atlanta, Georgia
Assistant Professor
Department of Oral and Maxillofacial Srugery
Martin B. Steed, DDS
Emory University
Assistant Professor and Residency Program Director
School of Medicine
Department of Surgery
Atlanta, Georgia
Division of Oral and Maxillofacial Surgery
Emory University
Saif S. Al-Bustani, DMD
Atlanta, Georgia
Resident
Department of Oral and Maxillofacial Surgery
Contributors Oregon Health and Science University
Portland, Oregon
John M. Allen, DMD
Former Attending Staff
Danielle Cunningham, DDS
Division of Oral and Maxillofacial Surgery
Resident
Department of Surgery
Department of Oral and Maxillofacial Surgery
School of Medicine
Emory University
Emory University Hospital Center
Atlanta, Georgia
Atlanta, Georgia
vii
FM-A04574.indd vii 6/27/2007 2:47:12 PM
viii Chapter Editors and Contributors
Fariba Farhidvash, MD Derek H. Lamb, DMD
Board Certifi ed Neurologist Resident
Private Practice Department of Surgery
Thomasville, Georgia Division of Oral and Maxillofacial Surgery
Mayo Clinic
Sam E. Farish DMD Rochester, Minnesota
Assistant Professor
Department of Surgery Joyce T. Lee, DDS, MD
Division of Oral and Maxillofacial Surgery Clinical Assistant Professor of Surgery
Emory University Department of Oral and Maxillofacial Surgery
School of Medicine; Emory University
Chief Atlanta, Georgia
Department of Oral and Maxillofacial Surgery
VA Medical Center Mehran Mehrabi, Maj. USAF, DC
Atlanta, Georgia Staff Oral and Maxillofacial Surgeon
Department of Oral and Maxillofacial Surgery
Jaspal Girn, DMD Keesler Air Force Base
Resident Biloxi, MS
Department of Oral and Maxillofacial Surgery
Emory University Roger A. Meyer, MD, DDS, FACS
Atlanta, Georgia Chairman of Oral and Maxillofacial Surgery
Northside Hospital;
Eric P. Holmgren, MS, DMD, MD Private Practice
Private Practice Atlanta Oral and Facial Surgery
Oral and Maxillofacial Surgery Associates Atlanta, Georgia
Bennington, Vermont and Pittsfi eld, Massachusetts
David G. Molen, DDS, MD
Anthony A. Indovina, Jr., DDS Private Practice, Molen Oral and Facial Surgery
Assistant Clinical Professor Auburn, Washington
Department of Oral and Maxillofacial Surgery
University of Minnesota Aric Murphy, DDS
Minneapolis, Minnesota; Resident
Private Practice Department of Oral and Maxillofacial Surgery
Dakota Valley Oral and Maxillofacial Surgery Mayo Clinic
Eagen, Minnesota Rochester, Minnesota
Jenny Jo, MD Timothy M. Osborn, DDS
Peachtree Women’s Clinic Resident
Atlanta Women’s Health Group Department of Oral and Maxillofacial Surgery
Atlanta, Georgia Oregon Health and Science University
Portland, Oregon
Matthew J. Karban, DMD
Resident Piyushkumar P. Patel, DDS
Department of Oral and Maxillofacial Surgery Private Practice
Mayo Clinic Atlanta, Georgia
Rochester, Minnesota
Vincent J. Pericaccante, DDS
Deepak G. Krishnan, BDS Clinical Assistant Professor
Chief Resident Division of Oral and Maxillofacial Surgery
Division of Oral and Maxillofacial Surgery Department of Surgery
Department of Surgery Emory University
School of Medicine School of Medicine;
Emory University Private Practice
Atlanta, Georgia Atlanta, Georgia
FM-A04574.indd viii 6/27/2007 2:47:12 PM
Chapter Editors and Contributors ix
David J.Rallis, DDS Scott D. Van Dam, DDS, MD
Resident Chief Resident
Department of Surgery Department of Oral and Maxillofacial Surgery
Mayo Clinic Mayo Clinic
Rochester, Minnesota Rochester, Minnesota
Kevin L. Rieck, DDS, MS, MD David Verschueren, DMD, MD
Instructor in Surgery Chief Resident
Mayo Clinic College of Medicine Department of Oral and Maxillofacial Surgery
Department of Surgery, Division of Oral and Maxillofacial Oregon Health and Science University
Surgery Portland, Oregon
Mayo Clinic
Rochester, Minnesota David M. Weber, DDS, MD
Resident
Ma’Ann C. Sabino, DDS, PhD Department of Oral and Maxillofacial Surgery
Assistant Professor Mayo Clinic
Division of Oral and Maxillofacial Surgery Rochester, Minnesota
University of Minnesota
Minneapolis, Minnesota Lee M. Whitesides, DMD, MMSc
Private Practice
Abtin Shahriari, DMD, MPH Atlanta Oral and Facial Surgery
Chief Resident Atlanta, Georgia
Division of Oral and Maxillofacial Surgery
Emory University Michael S. Wilkinson, DMD
Atlanta, Georgia Resident
Department of Oral and Maxillofacial Surgery
David C. Swiderski, DDS, MD Oregon Health and Science University
Resident Portland, Oregon
Division of Oral and Maxillofacial Surgery
Mayo Clinic Brian M. Woo, DDS, MD
Rochester, Minnesota Chief Resident
Department of Oral and Maxillofacial Surgery
Brett A. Ueeck, DMD, MD Oregon Health and Science University
Assistant Professor Portland, Oregon
Department of Oral and Maxillofacial Surgery
Oregon Health and Science University;
Attending Surgeon
Cleft Lip and Palate Team
Shriners Hospital for Crippled Children
Portland, Oregon
FM-A04574.indd ix 6/27/2007 2:47:12 PM
Foreword
The purpose of all clinical didactic knowledge is to apply it What are the key clinical fi ndings in this condition?
towards the care of a patient: more explicitly, care that results What further imaging and laboratory tests are needed to
in an improved outcome of a treatment intervention. Clinical quantify and qualify the clinical fi ndings or to confi rm
Review of Oral and Maxillofacial Surgery is an idea devel- a diagnosis?
oped by Shahrokh Bagheri during his fellowship in Portland. What are the goals of treatment?
Along with our other Emanuel Hospital fellows and Oregon What clinical interventions are demonstrated to be of
Health & Science University and University of Washington use?
residents, Dr. Bagheri was anxious to identify pathology that What complications might be anticipated?
requires treatment and to offer and execute treatment that What is the evidence to support the recommended approach
works. Now in private practice in Georgia, Dr. Bagheri works to a clinical problem?
with peers and residents to develop that same idea at Emory
The many residents who have participated in the develop-
University while maintaining the practical approach of the
ment of this text ensure that a systematic, evidence-based
practicing surgeon. This text is an embodiment of his thirst
approach to patient management is destined for a strong future
towards excellence in the practice of oral and maxillofacial
in our specialty. It is hoped that you, the reader, will be
surgery.
informed and inspired to seek further knowledge and evolve
Clinical Review of Oral and Maxillofacial Surgery seeks
your practice because of this contemporary exposition of
to apply clinical scientifi c knowledge in the performance of
knowledge. Clinical knowledge in oral and maxillofacial
a simulated clinical task described in the text. It applies diag-
surgery has been given a new baseline to encourage new
nostic skills, evidence-based treatment decisions, and treat-
investigation and surgical technique as a result of this impor-
ment protocols to the care of patients. Potential pitfalls and
tant contribution.
complications are described as well.
This text presents classical clinical situations in oral and
Leon A. Assael, DMD
maxillofacial surgery and identifi es the key issues in clinical
Professor and Chairman
practice.
Oral and Maxillofacial Surgery
What are the key anamnestic fi ndings in the given Oregon Health & Science University
condition? Portland, Oregon
xi
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Preface
The purpose of Clinical Review of Oral and Maxillofacial Each case illustrates the presentation, physical examina-
Surgery is to provide the readers of oral and maxillofacial tion fi ndings, laboratory and imaging studies, along with an
surgery with a systematic approach to the management of analysis of treatment options, complications, and discussion
patients presenting with the most common surgical or patho- of other relevant information.
logical conditions seen in this specialty. Contrary to tradi- The majority of the cases are illustrated by one or more
tional textbooks of surgery, this book emphasizes a case-based radiographs, clinical photographs, or drawings that further
approach to learning that is suitable for readers of oral and enhance the reader’s comprehension and retention of all
maxillofacial surgery at all levels of training or practice. Each content.
chapter contains more than just patient scenarios; instead it
presents carefully written teaching cases. Each of these cases
THE COMPANION CD-ROM
outlines essential information pertinent to the fundamental
aspects of the condition as they present in the practice of oral The CD-ROM included with this book features two simulated
and maxillofacial surgery. exams that allow the reader to both review the material and
Experience shows that learning is enhanced by incorporat- evaluate their test-taking skills. Each exam includes 200 mul-
ing teaching around real patient scenarios. In this manner, the tiple-choice questions, ranging in level of diffi culty. Feedback
reader is actively engaged in the case with the intent of raising is provided for each question. The questions are set up in a
the interest and, therefore, enhancing the retention of infor- format similar to the current National Board and in-service
mation presented. Traditional textbooks of surgery present the examinations, including the OMSSAT.
material in a fashion not directly related to a patient, but The “test mode” exam is timed and is comprised of a
instead list all the fi ndings, pathophysiology, and treatment randomized selection of questions pulled from a question
modalities. The intent of this book is not to replace a full- bank of over 400 questions. Each time the reader takes this
scope oral and maxillofacial surgery textbook, but instead exam the questions are randomized, so it will never be the
serve as a powerful learning tool for those interested in the same exam twice. As the exam is timed, the reader will be
fi eld. able to assess their test-taking strategy and make sure they
This book provides a rapid, concise, and easily compre- will be able to complete future exams in the time allotted.
hensible approach to disorders that readers can encounter in The “study mode” exam allows the reader to pick what
their work with patients. Predoctoral students will benefi t subject matter they want to include. For example, if the reader
from the basic presentation of the disorders and treatment wants to test themselves on radiology, infection, and trauma
options. More advanced readers (such as residents in training they will simply pick those chapters, and the question will be
or board candidates) will benefi t from the more detailed mate- incorporated into the exam. The exam can accommodate up
rial, and also become accustomed to the style of patient pre- to 200 questions. Using this exam, the reader will be able to
sentation that is refl ected in clinical practice and is currently review the specifi c material in which they are interested.
emphasized for oral and maxillofacial surgery boards and in Also included on the CD-ROM is an image collection
training examinations. containing every image that appears in the book in full color!
ORGANIZATION NOTE FROM THE EDITORS
The book is divided into 14 chapters, each comprised of The last several decades have brought dramatic changes to
separate sections that present a specifi c topic. A total of 95 the fi eld of oral and maxillofacial surgery. Recent reconstruc-
cases representing the full scope of modern practice of tive methods; imaging technology; distraction osteogenesis;
oral and maxillofacial surgery are included. Representative dental implants; rigid fi xation; full-scope training programs;
disorders or conditions have been chosen for each chapter and post-residency training fellowships in cosmetic surgery,
for teaching purposes. It is not possible to encompass every head and neck oncology, craniofacial syndromes, and trauma
disorder or condition in each chapter; therefore, the ones have rapidly reshaped this exciting specialty in the last 20
included are the most common, or have signifi cant implica- years. We hope that our readers enjoy and learn from this
tions for modern clinical practice. The references for each book as much as we did during its preparation.
case include both historic articles and recent additions to Shahrokh C. Bagheri
the fi eld. Chris Jo
xiii
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1 Oral and Maxillofacial
Radiology
Shahrokh C. Bagheri, DMD, MD
This chapter addresses:
• Multilocular Radiolucent Lesion in the Pericoronal Region
(Odontogenic Keratocyst)
• Unilocular Radiolucent Lesion of the Mandible (Dentigerous Cyst)
• Multilocular Radiolucent Lesion in the Periapical Region
(Ameloblastoma)
• Unilocular Radiolucent Lesion in a Periapical Region (Periapical
Cyst)
• Mixed Radiolucent-Radiopaque Lesion (Ossifying Fibroma)
Interpretation of radiographs is a routine part of the daily A complete discussion of the full spectrum of radiographic
practice of oral and maxillofacial surgery. Radiographs pathology is beyond the scope of this book, but here the
that are commonly obtained in the offi ce include periapical, radiographic presentation of fi ve important and representative
occlusal, panoramic, and lateral cephalometric views. pathological processes is provided in case format. Included in
Computed tomography (CT) scans, although costly, are avail- each case is the differential diagnosis of associated conditions
able in some offi ces. Knowledge of normal radiographic to guide further study.
anatomy and recognition of pathological conditions are Figure 1-1 shows the most common location of several radio-
essential. graphically detectable maxillofacial pathological processes.
Posterior maxilla Anterior maxilla
• Pagets disease of bone • Adenomatoid odontogenic
tumor (AOT)
• Nasopalatine duct cyst
Posterior mandible • Lateral periodontal cyst
• Dentigerous cyst (botryoid type)
• Odontogenic keratocyst • Odontoma
• Ameloblastoma • Pagets disease of bone
• Intraosseous
mucoepidermoid carcinoma
• Stafne bone defect (below canal) Anterior mandible
• Idiopathic bone marrow defect • Periapical cemento osseous
• Calcifying epithelial dysplasia
odontogenic tumor (CEOT) • Central giant cell granuloma
• Odontoma
Figure 1-1 The most common location of several radiographically detectable maxillofacial pathological processes.
1
Ch001-A04574.indd 1 6/27/2007 2:48:01 PM
Multilocular Radiolucent Lesion in the Pericoronal Region
(Odontogenic Keratocyst)
Piyushkumar P. Patel, DDS, and Chris Jo, DMD
indicative of a malignant process). The intercanthal distance
CC
is 33 mm (normal), and there is no evidence of frontal bossing.
A 20-year-old man is referred for evaluation of a swelling on His occipitofrontal circumference is normal (an intercanthal
his right mandible. distance [the distance between the two medial canthus of the
palpebral fi ssures] of greater than 36 mm is indicative of
Odontogenic Keratocysts hypertelorism, and an occipitofrontal circumference greater
Odontogenic keratocysts (OKCs) show a slight predilection than 55 cm is indicative of frontal bossing; both can be seen
for males with a peak incidence between 11 and 40 years of with NBCCS).
age. Patients with larger lesions may present with pain sec- Neck. There are no palpable masses and no cervical or
ondary to infection of the cystic cavity. Smaller lesions are submandibular lymphadenopathy. Positive lymph nodes
usually asymptomatic and are frequently diagnosed during would be indicative of an infectious or a neoplastic process;
routine radiographic examination. a careful neck examination is paramount in the evaluation of
any head and neck pathology.
Intraoral. Occlusion is stable and reproducible. The right
HPI
mandibular third molar appears to be distoangularly impacted
The patient complains of a 1-month history of progressive, (OKCs do not typically alter the occlusion). The interincisal
nonpainful swelling of his right posterior mandible (65% to opening is within normal limits. There is buccal expansion
83% of OKCs occur in the mandible, most often in the pos- of the right mandible extending from the right mandibular
terior body and ramus region). The patient denies any history fi rst molar area posteriorly toward the ascending ramus.
of pain to his right lower jaw, fever, purulence, or trismus. He Resorption of bone may include the cortex at the inferior
does not report any neurosensory changes (which are gener- border of the mandible, but this is observed at a slower
ally not seen with OKCs). rate than intermedullary bone, which is less dense. For this
reason, OKCs characteristically extend anteroposteriorly than
buccolingually. This pattern of expansion into less-dense
PMHX/PDHX/MEDICATIONS/ALLERGIES/SH/FH
bone explains why maxillary OKCs show more buccal than
Noncontributory. There is no family history of similar pre- palatal expansion and often expand into the maxillary
sentations. sinus. There is no palpable thrill or audible bruit, which are
Nevoid basal cell carcinoma syndrome (NBCCS) is an seen with arteriovenous malformations. The oral mucosa is
autosomal dominant inherited condition with features that normal in appearance with no signs of acute infl ammatory
can include multiple basal cell carcinomas of the skin, mul- processes.
tiple OKCs, intracranial calcifi cations, and rib and vertebral Thorax-Abdomen-Extremity. The patient has no fi nd-
anomalies. Many other anomalies have been reported with ings suggestive of NBCCS (e.g., pectus excavatum, rib
this syndrome (Box 1-1). The prevalence of the NBCCS is abnormalities, palmar or plantar pitting, and skin lesions)
estimated to be 1:60,000. (see Box 1-1).
EXAMINATION IMAGING
Maxillofacial. The patient has slight lower right facial swell- A panoramic radiograph is the initial screening examination
ing isolated to the lateral border of the mandible and not of choice for patients presenting for evaluation of intraosseous
involving the area below the inferior border. The mass is hard, mandibular pathology (10% to 20% of OKCs are incidental
nonfl uctuant, and nontender to palpation (large cysts may radiographic fi ndings). This provides an excellent overview
rupture and leak keratin into the surrounding tissue, provok- of the bony architecture of the maxilla, mandible, and associ-
ing an intense infl ammatory reaction that causes pain and ated structures. Bony and soft tissue window CT scans of the
swelling). There are no facial or trigeminal nerve defi cits mandible and neck are recommended when large lesions are
(paresthesia of the inferior alveolar nerve would be more found. CT scans are valuable in that they provide additional
2
Ch001-A04574.indd 2 6/27/2007 2:48:02 PM
Multilocular Radiolucent Lesion in the Pericoronal Region (Odontogenic Keratocyst) 3
Box 1-1. M ajor Features of the Nevoid Basal
Cell Carcinoma Syndrome
50% or Greater Frequency
Multiple basal cell carcinomas
Odontogenic keratocysts
Epidermal cysts of the skin
Palmer-planter pits
Calcifi ed falx cerebri
Enlarged head circumference
Rib anomalies (splayed, fused, partially missing, bifi d)
Mild ocular hypertelorism
Spina bifi da occulta of cervical or thoracic vertebrae
15% to 49% Frequency
Calcifi ed ovarian fi bromas
Short fourth metacarpals
Kyphoscoliosis or other vertebral anomalies
Pectus excavatum or carinatum Figure 1-2 Preoperative panoramic radiograph showing a large
Strabismus multilocular radiolucent lesion of the right mandible body and
Less Than 15% Frequency ramus associated with an impacted third molar.
Medulloblastoma
Meningioma
Lymphomesenteric cysts LABS
Cardiac fi broma
No laboratory tests are indicated unless dictated by the
Fetal rhabdomyoma
Marfanoid build medical history.
Cleft lip and palate Fine-needle aspiration (FNA) biopsy and cytokeratin-10
Hypogonadism in males immunocytochemical staining have been shown to differenti-
Mental retardation ate OKCs from dentigerous and other nonkeratinizing cysts.
Despite their availability, these techniques are not routinely
From Gorlin RJ: Nevoid basal-cell carcinoma syndrome, Medicine 66:98- ordered.
113, 1987.
DIFFERENTIAL DIAGNOSIS
The differential diagnosis of multilocular radiolucent lesions
information such as proximity of adjacent structures (e.g., can be divided into lesions of cystic pathogenesis, neoplastic
mandibular canal), integrity of cortical plates, and presence (benign or malignant) lesions, and vascular anomalies (which
of perforations into adjacent soft tissues. CT scans provide are least common). The differential diagnosis of multilocular
accurate assessment of the size of the lesion and can demon- radiolucent lesions is listed in Box 1-2 and can be further
strate additional anatomic details (or lesions) that do not narrowed by clinical presentation. Special considerations
appear on panoramic radiographs. For evaluation of osseous should be given to radiolucent lesions with poorly defi ned or
structures, non–contrast-enhanced CT scans are most ragged borders, which have a separate differential.
informative.
In addition, three-dimensional volume-reconstructed scans
BIOPSY
can be obtained. This imaging study reconstructs the bony
framework of the facial skeleton and can be helpful when An incisional or excisional biopsy can be performed depend-
large intraosseous pathology is encountered. It has been dem- ing on the size of the lesion. A smaller cystic lesion can be
onstrated that T2-weighted magnetic resonance imaging completely excised, whereas larger lesions require an inci-
(MRI) can detect OKCs in 85% of new cases with a readily sional biopsy to guide fi nal therapy. It is important to aspirate
recognizable pattern. However, the use of MRI for manage- the lesion before incising into the lesion (entering carefully
ment of suspected OKCs is not routine. through the cortical bone) to rule out a vascular lesion. The
In this patient, the panoramic radiograph reveals a large, aspiration of bright red blood alerts the surgeon to a high-fl ow
multilocular radiolucent lesion with possible displacement vascular lesion, such as an arteriovenous malformation, which
of the right mandibular third molar (Figure 1-2) (70% of could result in uncontrollable hemorrhage. In such a case, the
OKCs present as a unilocular radiolucent lesion). The procedure should be aborted for further radiographic and
multilocular appearance is more commonly seen with maxil- angiographic studies to characterize the vasculature of the
lary OKCs. There are also several carious teeth and a retained area. The aspiration of straw-colored (or clear) fl uid is char-
root tip of the right mandibular second bicuspid (tooth acteristic of a cystic lesion, whereas the absence of any aspi-
No. 29). rate may be seen with a solid mass (tumors).
Ch001-A04574.indd 3 6/27/2007 2:48:02 PM