ORALMEDICINE by liaoqinmei



                                             Test 98.2

Developmental Mandibular
Salivary Gland Defect
The Importance of Clinical Evaluation
                              developmental mandibular salivary

                     A        gland defect (also known as static
                              bone cyst, static bone defect, Stafne
                     bone cavity, latent bone cyst, latent bone
                     defect, idiopathic bone cavity, developmen-
                     tal submandibular gland defect of the
                     mandible, aberrant salivary gland defect in
                     the mandible, and lingual mandibular bone
Sako Ohanesian,      concavity) is a deep, well-defined depression
DDS                  in the lingual surface of the posterior body
                     of the mandible. More precisely, the most
                     common location is within the submandibu-
                     lar gland fossa and often close to the inferi-
                     or border of the mandible. In developmental
                     bone defects investigated surgically, an
                     aberrant lobe of the submandibular gland
                     extends into the bony depression.
                         First recognized by Dr. Edward Stafne in
                     1942, numerous cases of developmental
                     mandibular salivary gland defect have since
                     been reported, and the lesion should not be
                     considered rare.1 In a study of 4963 pan-

                     Most authorities now agree that
                     this entity is a congenital
                     defect, although it has rarely
                     been observed in children and
                     its precise anatomic nature is
                     still uncertain.
                     oramic images of adult patients, 18 cases of     Figure 1. CT slices/panoramic views showing a well-defined radiolucent lesion in the right mandible.
                     salivary gland depression were found by
                     Karmiol and Walsh2, an incidence of nearly
                     0.4%. Most authorities now agree that this       The margins of the radiolucent defect are                around an extension of salivary tissue. This
                     entity is a congenital defect, although it has   well-defined by a dense radiopaque line.                 theory is supported by findings of radiolu-
                     rarely been observed in children and its pre-    This cortical margin is usually thicker on               cencies in association with each of the 3 sali-
                     cise anatomic nature is still uncertain. Also    the superior aspect. This appearance is the              vary glands. Most surgical series have noted
                     unexplained is the fact that far more cases      result of the x-rays passing tangentially                salivary tissue within the bony defect, but
                     have been reported in men than in women.3        through the relatively thick walls of the                muscle, lymphatic tissue, and blood vessel
                          The lesion, usually asymptomatic and        depression. It is occasionally bilateral. The            have also been reported.
                     discovered during routine radiographic ex-       radiolucent defect may represent either                      The lesion may be regarded properly as
                     amination, appears as an ovoid radiolucen-       actual enclavement of salivary gland tissue              a developmental defect rather than a patho-
                     cy, generally situated between the mandibu-      within the mandible during embryonic                     logic lesion. Histologically, normal salivary
                     lar canal and the inferior border of the         development or, more frequently, an inden-               tissue is found, and no treatment is required
                     mandible, just anterior to the angle. Rare       tation on the mandible with a portion of the             except routine radiographic follow-up. It can
                     examples are located in the apical region of     submaxillary gland lying within the defect.              and should be differentiated from the trau-
                     the mandibular premolars or cuspids, and         Salivary gland defects are presumed to form              matic bone cyst (also referred to as hemor-
                     are related to the sublingual gland fossa.       by the remodeling of the mandibular cortex                                               continued on page 118

                                                                                                ORAL MEDICINE
Developmental Mandibular...
continued from page 116
Xxxx... Comparison of Various Lesions That Can Be Confused With Static Bone Defect.
  Table.                                                                                                                                      7,12,13

                                  Etiology                    Clinical Presentation             Radiographic Findings                      Diagnosis                            Treatment                             Prognosis

     Traumatic         Unknown in most cases; may          Peaks in second decade; usual-    Clearly defined radiolucency;       Radiographic appearance; clini-      Surgical exploration; observa-     Excellent; small risk of recur-
     bone cyst         be due to traumatic injury pro-     ly in body of mandible; pain-     margins may be uneven but           cal finding of an empty bony         tion for resolution.               rence.
                       ducing intramedullary hemor-        less in most cases; swelling      clear; may extend between           space (pseudocyst); collagen
                       rhage and subsequent clot           noted in one fourth               tooth roots creating                and fibrin line the dead space;
                       resorption; alternative theory      of cases.                         a scalloped pattern.                lamellar bone may be noted
                       suggests degeneration of pri-                                                                             along the bony margin.
                       mary intrabony pathology.

Mandibular salivary    Developmental depression of         No symptoms; discovered           Round to ovoid radiolucency         Radiographic appearance.             Recognition only.                  Excellent.
gland defect (Stafne   the lingual side of the             incidentally.                     below inferior alveolar canal,
    bone cavity)       mandible; the aberrant lobe of                                        above inferior border and
                       the submandibular salivary                                            below third molar area; well-
                       gland and/or adipose tissue                                           defined by a dense hypercorti-
                       fills the body of mandible                                            cated margin; size range of one
                       defect; depression created pro-                                       to 3 cm; rarely noted in premo-
                       duces characteristic radi-                                            lar and canine areas.
                       ographic findings.

    Periapical         A radicular cyst that most likely   Often, periapical cysts do not    Located approximately in the        A cyst that becomes large may        Treatment of a tooth with a        Excellent; recurrence is
       cyst            results when rests of epithelial    produce symptoms unless sec-      apex of a nonvital tooth; occa-     cause swelling; the swelling         radicular cyst may include         unlikely if removed completely.
                       cells in the periodontal liga-      ondary infection occurs.          sionally, appear on the mesial      may feel bony and hard if the        extraction, endodontic therapy,
                       ment are stimulated by inflam-                                        or distal surface of a tooth        cortex is intact, crepitant as the   and apical surgery; treatment
                       matory products from a nonvi-                                         root, at the opening of an          bone thins, and rubbery if           of a large cyst usually involves
                       tal tooth.                                                            accessory canal, or infrequent-     bone destruction has occurred;       surgical removal or marsupial-
                                                                                             ly in a deep periodontal pocket;    outline of cyst is usually           ization.
                                                                                             most (60%) found in the             curved or circular unless
                                                                                             maxilla.                            influenced by surrounding
                                                                                                                                 structures such as cortical

    Dentigerous        A developmental odontogenic         Most commonly involves fre-       Well-defined radiolucency           Cysts without secondary              Cyst enucleation and extraction    Excellent; possible complica-
       cyst            cyst arising subsequent to sep-     quently impacted teeth:           enclosing crown of unerupted        inflammation are thin, cuboidal,     of associated tooth; marsupial-    tions include: pathologic frac-
                       aration between dental follicle     mandibular third molars, fol-     tooth; corticated/opaque mar-       nonkeratinized epithelial lining     ization prior to excision may be   ture with large lesions and
                       and the crown of an associated      lowed by maxillary canines;       gins unless infected; may pro-      2 cell layers thick with flat        considered if very large.          neoplastic transformation of
                       unerupted tooth; proliferation      usually noted during second       duce root resorption of adja-       epithelial-connective tissue                                            epithelial lining.
                       of reduced enamel epithelium        and third decades; asympto-       cent erupted teeth; usually         interface; loosely arranged col-
                       lining the follicle, with fluid     matic and discovered on rou-      unilocular; less commonly           lagen bundles; cysts with sec-
                       accumulation between epitheli-      tine radiographic examination;    multilocular.                       ondary inflammation have
                       um and impacted tooth crown;        painless jaw/alveolar expansion                                       hyperplastic, nonkeratinized
                       degeneration of the stellate        may occur; cortex is thinned                                          squamous epithelial lining with
                       reticulum component of enam-        and rarely perforated.                                                epithelial ridge development;
                       el organ occurs during odonto-                                                                            variable chronic inflammatory
                       genesis.                                                                                                  cell infiltrate within condensed
                                                                                                                                 collagen stroma.

   Odontogenic         A benign, aggressive develop-       5% to 15% of odontogenic          Can occur in any area of maxil-     Radiographic features.               Excision with curettage of bony    Recurrence rate varies from
    keratocyst         mental odontogenic cyst; may        cysts; usually occurs sporadi-    la or mandible; rarely may                                               confines.                          10% to 30% (greatest in
                       be associated with mutation of      cally as an isolated finding;     arise in gingival soft tissue                                                                               patients with a syndrome).
                       PTCH tumor suppressor gene.         about 5% are associated with      only, mandible is preferred site
                                                           nevoid basal cell carcinoma;      in 65% to 78% of cases; often
                                                           5% of patients have multiple      seen in a dentigerous relation-
                                                           odontogenic keratocysts           ship; discrete radiolucency,
                                                           (OKCs) and no syndrome.           usually in relation to teeth; may
                                                                                             be unilocular to multilocular.

   Nonossifying        Unknown in most cases;              Majority of all NOFs are          On plain film radiographs,          Histologically, the lesions con-     Treatment varies depending on      Generally excellent.
     fibroma           lesions occur as a result of        asymptomatic and are discov-      NOFs appear as eccentric,           tain whorled bundles of con-         the size and severity of the
                       developmental aberrations at        ered incidentally on radi-        multi or uniloculated, ovoid        nective tissue cells admixed         NOF; surgery is often not
                       the epiphyseal plate; not neo-      ographs; symptomatic lesions      lesions in the metaphysis of        with foamy histocytes, hemo-         required to treat NOF due to a
                       plasms, but developmental           may present with mild pain        bone with sclerotic margins;        siderin, hemorrhage, collagen,       high rate of spontaneous
                       defects; tend to occur after the    and swelling of short duration;   lesions may extend into the         multinucleated giant cells, and      regression and a lack of symp-
                       age of 2, a muscle pull and         may have bone tenderness          medullary cavity; long axis of      bone trabeculae.                     toms; symptomatic lesions
                       periosteal injury may be a con-     with palpation.                   the NOF is most commonly                                                 should first be treated conserv-
                       tributing factor.                                                     seen parallel to the long axis of                                        atively—conservative care con-
                                                                                             the bone and are usually locat-                                          sists of limited activity and
                                                                                             ed medially.                                                             immobilization, in addition to
                                                                                                                                                                      yearly or bi-yearly radiographs;
                                                                                                                                                                      curettage or bone grafting.


                          Etiology                 Clinical Presentation              Radiographic Findings                          Diagnosis                             Treatment                            Prognosis

   Fibrous      Unknown in most cases;           Occurs with equal predilec-      Generally a small unilocular radi-   Monostatic fibrous dysplasia is often      Surgical removal of lesion.          Majority of lesions are too
  dysplasia     skeletal aberrations consti-     tion for males and females;      olucency or a somewhat larger        discovered as an incidental radi-                                               large at the time of original
                tute the cardinal feature; the   more common in children          multilocular radiolucency; both      ographic finding; patients with jaw                                             diagnosis to excise surgical-
                condition is often monostot-     and young adults; painless       with a rather well-circumscribed     involvement first may complain of                                               ly without leaving facial
                ic, but may be polyostotic;      swelling or bulging of the       border and containing a network      unilateral facial swelling or an enlarg-                                        deformity or, in the case of
                monostatic fibrous dysplasia     jaw; swelling usually            of fine bony trabeculae; increased   ing deformity of the alveolar process;                                          the mandible, weakening of
                is of greater concern to the     involves the labial or buccal    trabeculation could render the       pain and pathologic fractures are                                               the bone so as to invite
                dentist due to frequency         plate, seldom the lingual        lesion more opaque; the periph-      rare; if extensive craniofacial lesions                                         pathologic fracture; numer-
                with which jaws are affected;    aspect; possible malalign-       ery of lesions most commonly is      have impinged on nerve foramina,                                                ous cases reported in which
                nearly every bone has been       ment, tipping or displace-       ill defined, with a gradual blend-   neurologic symptoms such as anos-                                               monostotic fibrous dyspla-
                reported involved.               ment of teeth; mucosa is         ing of normal trabecular bone        mia, deafness, or blindness may                                                 sia has undergone sponta-
                                                 almost invariably intact over    into an abnormal trabecular pat-     develop.                                                                        neous malignant transfor-
                                                 the lesion.                      tern.                                                                                                                mation into sarcoma.

Ameloblastoma   A benign, aggressive jaw         Peak incidence during third      Osteolytic or radiolucent with       Sheets, strands, islands of odonto-        Varies with subtype, size,           Generally good, recurrence
                tumor of odontogenic             to fifth decades; 80% occur      sclerotic, smooth, even borders;     genic epithelium; peripheral layer of      and location; solid/multi-           rates higher with conserva-
                epithelial ectodermal origin;    in the mandible, chiefly in      may be unilocular to multilocular;   cuboidal to columnar ameloblast-           cystic lesions generally             tive treatment; recurrence
                the most common odonto-          molar and ramus region;          root resorption or tooth displace-   like cells enclosing a cell population     require local incision or            rates of up to 15% follow-
                genic tumor after the odon-      often presents in association    ment may be seen; can expand         analogous to stellate reticulum of         resection; cystic variant            ing marginal resection;
                toma; incidence of 0.3 cases     with unerupted third molar       affected jaw; cortical perforation   the enamel organ; several histologic       requires local excision as           long-term follow-up
                per million people.              teeth; may produce marked        may occur.                           patterns described have no clinical        recurrences may follow               necessary.
                                                 deformity, facial asymmetry;                                          relevance; malignant variants rarely       curettage only.
                                                 peripheral variant arises in                                          seen.
                                                 gingival tissue of older
                                                 adults fifth to seventh
                                                 decades; slow growing, but

    Giant       Probably reactive or respon-     Bony expansion; most cases       Usually multilocular, occasionally   Incisional biopsy; primary hyper-          Thorough curettage; margin-          Aggressive variant has high
  cell tumor    sive in nature; speculation      in those less than 30 years      unilocular, radiolucency; margins    parathyroidism should be ruled out.        al resection if aggressive or        recurrence rate; generally
                suggests it may present a        of age; female predomi-          are usually well defined; borders                                               recurrent; Calcitonin may be         good.
                developmental anomaly .          nance; near exclusivity in       may be scalloped; can displace                                                  successful in some cases;
                                                 mandible or maxilla—rarely       teeth; wide-size variation at time                                              intralesional corticosteroid
                                                 in facial bones; occurrence in   of presentation.                                                                placement in small lesions
                                                 mandible predominates 3:1                                                                                        may be successful.
                                                 over that in maxilla; usually
                                                 anterior to molar teeth; most
                                                 cases are nonaggressive,
                                                 slow growing, and asympto-
                                                 matic; some cases are recur-
                                                 rent and exhibit aggressive
                                                 behavior with pain, perfora-
                                                 tion, and rapid enlargement;
                                                 no radiographic or histologic
                                                 features can be used to sep-
                                                 arate nonaggressive lesions
                                                 from aggressive lesions.

    Focal       Etiology is unknown but has      In reported cases, 77%           Lesion has a predilection for the    The roentgenographic appearance of         Recognition only; when               Good.
 osteoporotic   been postulated to be bone       occurred in women, and           mandibular molar area, generally     the focal osteoporotic bone marrow         doubt exists about the true
 bone marrow    marrow hyperplasia, per-         they involved the mandible       appears as a radiolucency of vari-   defect of the jaws is not unlike that      nature of the radiolucency, a
    defect      sistent embryologic marrow       in 83% of cases; asympto-        able size, a few millimeters to a    of residual dental infections, central     longitudinal study with films
                remnants, or site of abnor-      matic and discovered only        centimeter or more, with a poorly    neoplasms, or even the traumatic           at 3-month intervals may be
                mal healing following            during routine roentgeno-        defined periphery indicative of      cyst of bone.                              prescribed; the marrow
                extraction, trauma, or           graphic examination.             lack of reactivity of adjacent                                                  space should not increase
                local inflammation.                                               bone; most common in edentu-                                                    in size.
                                                                                  lous areas, suggesting they result
                                                                                  from failure of normal bone
                                                                                  regeneration after tooth extrac-

    Basal       A hereditary condition,          Complex syndrome which           Multiple keratocysts may devel-      Starts to appear early in life, usually    High recurrence rate of the          It is reasonable to examine
  cell nevus    transmitted as an autosomal      includes a variety of possible   op bilaterally and can vary in       after 5 years of age and before 30,        keratocysts associated with          the patient yearly for new
  syndrome      dominant trait, with high        abnormalities including den-     size from one mm to several          with development of jaw cysts and          this syndrome; several cases         and recurrent cysts; a
                penetrance and variable          tal and osseous anomalies        centimeters in diameter; a           skin, basal cell carcinomas; lesions       of ameloblastoma have                panoramic film serves as an
                expressivity.                    such as odontogenic kerato-      radiopaque line of the calcified     occur in multiple quadrants; the pres-     developed in cysts, thus             adequate screening film;
                                                 cysts and mild mandibular        falx cerebri may be prominent        ence of cortical boundary and other        emphasizing the importance           referral for genetic counsel-
                                                 prognathism.                     on the posteroanterior skull pro-    cystic characteristics differentiate       of surgical removal of the           ing may be appropriate.
                                                                                  jection; occasionally the calcifi-   basal cell nevus syndrome from other       cysts and their histologic
                                                                                  cation may appear laminated.         abnormalities characterized by multi-      examination.
                                                                                                                       ple radiolucencies.

    Brown       May appear in any bone, but      Variably defined margins         Occasionally peripical radi-         Manifestations cover a broad range,        Surgical removal; the site of        After successful surgical
  tumor in      are frequently found in the      and may produce cortical         ographs reveal loss of the lamina    but most patients have renal calculi,      brown tumor heals with               removal of the causative
hyperparathy-   facial bones and jaws; these     expansion; if solitary, tumor    dura in patients with hyper-         peptic ulcers, psychiatric problems,       bone that is radiographically        parathyroid adenoma,
   roidism      lesions may be multiple          may resemble a central giant     parathyroidism; loss of lamina       or bone and joint pain; gradual loos-      more sclerotic than normal.          almost all radiographic
                within a single bone.            cell granuloma, therefore, if    dura may occur around one tooth      ening, drifting, and loss of teeth may                                          changes revert to normal;
                                                 a giant cell granuloma           or all the remaining teeth.          occur; because of daily fluctuations,                                           the site of a brown tumor
                                                 occurs later than the second                                          the serum calcium level should be                                               often heals with bone that is
                                                 decade, the patient should                                            tested at different intervals; the                                              radiographically more scle-
                                                 be screened for an increase                                           serum alkaline phosphatase level may                                            rotic than normal.
                                                 in serum calcium, PTH, and                                            be elevated in hyperparathyroidism.
                                                 alkaline phosphatase.

                                                                                                                                                                                                       continued on page 120

                                                                                                                                                                                                  FEBRUARY 2008 • DENTISTRY TODAY

                                                                   ORAL MEDICINE

Developmental Mandibular...              the roentgenogram as a rather
continued from page 119                  poorly circumscribed radiolucency
                                         in a location between the central
rhagic bone cyst). The traumatic         incisor and first premolar area.
bone cyst is an uncommon, unlined        They are far less common than the
cavity of the jaws. Clinically, the      posterior lesion. A complication
lesion is asymptomatic in the major-     occasionally reported in the litera-
ity of cases and is often accidentally   ture is the development of a true
discovered on routine radiological       central salivary gland neoplasm
examination. Pain is the presenting      from the included salivary gland
symptom in 10% to 30% of the             tissue, but this is rare.7
patients. Other, more unusual sym-
ptoms include tooth sensitivity,                   CASE REPORT
paresthesia, fistulas, delayed erup-     The patient in this case was a white
tion of permanent teeth, displace-       36-year-old male, with failed en-
ment of the inferior dental canal,       dodontic therapy involving tooth
and pathologic fracture of the man-      No. 19. The patient was healthy         Figure 2. Lesion in standard panoramic x-ray and implant placement.
dible.4-6 Expansion of the cortical      (ASA I), did not report any relevant
plate of the jawbone is often noted,     information regarding medical or
usually buccally, resulting in intrao-   dental history, and did not mention     bone cavity was made, and no fur-                  Dental professionals are facing
ral and extraoral swelling and sel-      the use of any medication. Ex-          ther therapy was instituted. The               an ever-increasing emphasis on a
dom causing deformity of the face.       pansion of the mandible and hydra-      pathologist’s recommendation was               thorough clinical examination of
On radiological examination, a           tion of mucous membrane were nor-       to simply observe the area radi-               each patient. As a result, the dentist
traumatic bone cyst usually ap-          mal. Endodontic consultation con-       ographically in the event that it              is often confronted with the need to
pears as a unilocular radiolucent        firmed root fracture, and the tooth     became enlarged and would necessi-             further evaluate any deviation from
area with an irregular but well-         was extracted and replaced with a       tate a surgical biopsy.                        normal, including the decision to
defined (or partly well-defined) out-    root form implant. The option of a 3-                                                  biopsy a suspected lesion. To avoid
line, with or without sclerotic lin-     unit bridge was given to patient.                    DISCUSSION                        any unnecessary procedures and
ing around the periphery of the          The radiograph disclosed a well cir-    Many terms have been used to                   treatments, it is important to be
lesion. The traumatic bone cyst          cumscribed radiolucency inferior        describe asymptomatic radiolucen-              aware of the existence of other
almost invariably lies above the         to the mandibular canal and located     cies at the angle of the mandible.             anatomic variations in the exami-
mandibular canal on the intraoral        in the region of the right mandib-      Similar defects related to the sub-            nation process. Awareness of these
periapical roentgenogram, while the      ular second and third molars            lingual and parotid glands have                entities can save the patient from
salivary gland depression lies below     (Figures 1 and 2). The diameter         been described, located at the                 unnecessary invasive procedures.
the canal. Nevertheless, definitive      measured approximately 2 cm. No         mandibular symphysis and the                       Most case reports of Stafne bone
differential diagnosis from other        symptoms were reported.                 mandibular rami, respectively.8-10             cavities have discussed the find-
lesions sometimes cannot be made             On 3-dimensional imaging views      Some researchers apply the term                ings on intraoral dental films, plain
without surgical exploration.            of the lingual aspect of the man-       Stafne bone cyst to lesions associat-          films of the mandible, or orthopan-
    It has been recognized that a        dible obtained with a NewTom 3D         ed with any of the salivary glands,            tographs. Although these imaging
sublingual salivary gland depression     cone beam CT scanner (AFP Im-           while others restrict the term to the          techniques are often sufficient for
or inclusion may occur on the lingual    aging Corp), it was observed that       submandibular gland, preferring                diagnosis, they may not be definitive
surface of the anterior segment of       this radiolucency represented a cor-    more specific terms such as anterior           when the lesion is atypical. In these
the mandible. These asymptomatic         tical indentation or depression         lingual mandibular salivary gland              situations, confirmatory testing is
lesions have generally appeared on       (Figure 3). A diagnosis of Stafne       defect for the sublingual gland.11             warranted, as the differential diag-
                                                                                                                                        nosis for mandibular radi-
                                                                                                                                        olucencies includes traumat-
                                                                                                                                        ic bone cyst, periapical cyst,
                                                                                                                                        dentigerous cyst, odontogenic
                                                                                                                                        keratocyst, nonossifying fi-
                                                                                                                                        broma, fibrous dysplasia, am-
                                                                                                                                        eloblastoma, giant cell tu-
                                                                                                                                        mor, focal osteoporotic bone
                                                                                                                                        marrow defect, basal cell
                                                                                                                                        nevus syndrome, and brown
                                                                                                                                        tumor of hyperparathyroid-
                                                                                                                                        ism. (See Table.7,12,13)

                                                                                                                                         Given the possible clinical
                                                                                                                                         presentation of the various
                                                                                                                                         lesions described, it is im-
                                                                                                                                         portant for the dentist to be
                                                                                                                                         aware of the existence of
                                                                                                                                         these anatomic variations
                                                                                                                                         in the examination process.
                                                                                                                                         Cystic-appearing lesions
                                                                                                                                         that occur in the mandible
                                                                                                                                         are often difficult to distin-
                                                                                                                                         guish from one another with
                                                                                                                                         radiography. They are all
                                                                                                                                         usually benign, but some
                                                                                                                                         can be locally aggressive
                                                                                                                                         and destructive. The patient

                                         FREEinfo, circle 86 on card

                                                                                                           Continuing Education
                                                                                                           Test No. 98.2
                                                                                                                  o submit Continuing Education answers, use the answer sheet on
                                                                                                                  page 122. On the answer sheet, identify the article (this one is Test
                                                                                                                  98.2), place an X in the box corresponding to the answer you
                                                                                                           believe is correct, detach the answer sheet from the magazine, and mail to
                                                                                                           Dentistry Today Department of Continuing Education.

                                                                                                                The following 8 questions were derived from the article Developmental
                                                                                                           Mandibular Salivary Gland Defect: The Importance of Clinical Evaluation by
                                                                                                           Sako Ohanesian, DDS, on pages 116 through 121.

                                                                                                            Learning Objectives

                                                                                                           After reading this article, the individual will learn:
                                                                                                              • to differentiate a developmental salivary gland defect from traumatic
                                                                                                                bone cysts and other lesions.
                                                                                                              • to recognize the clinical and radiographic appearance of a develop-
                                                                                                                mental mandibular salivary gland defect (the intention is to avoid
                                                                                                                unnecessary biopsy).

                                                                                                           1. A developmental salivary gland        5. The developmental salivary
                                                                                                              defect is located:                       gland defect is best described
                                                                                                                 a.   above the mandibular canal.      as:
                                                                                                                 b.   below the mandibular canal.         a. benign neoplasm.
                                                                                                                 c.   at the crest of the bone.           b. variations of normal.
                                                                                                                 d.   at the tuberosity.                  c. cyst.
                                                                                                                                                          d. a premalignant lesion.

                                                                                                           2. Treatment for a salivary gland
Figure 3. The 3-D images show a cortical depression.                                                          defect includes:                      6. Differential diagnosis for man-
                                                                                                                 a.   chemotherapy.                    dibular radiolucencies may
                                                                                                                 b.   surgical intervention.           include:
history and careful consideration of                    resembling developmental bone cavity                                                              a.   dentigerous cyst.
                                                        (Stafne). Proc Finn Dent Soc. 1985;81:215-               c.   radiation.
the location of the lesion within the                   221.                                                     d.   none—recognition only.              b.   traumatic bone cyst.
mandible, its borders, its internal                 10. Barker GR. A radiolucency of the ascending                                                        c.   odontogenic keratocyst.
                                                        ramus of the mandible associated with invest-
architecture, and its effects on                        ed parotid salivary gland material and analo-                                                     d.   all of the above.
adjacent structures generally make                      gous with a Stafne bone cavity. Br J Oral
                                                                                                           3. Clinical presentation of the sali-
                                                        Maxillofac Surg. 1988;26:81-84.
it possible to narrow the differen-                 11. Barak S, Katz J, Mintz S. Anterior lingual            vary gland defect is:
tial diagnosis. Awareness of these                      mandibular salivary gland defect: a dilemma in
                                                                                                                 a. asymptomatic—discovered inci-
                                                                                                                                                    7. Size of the Stafne bone defect
entities can save the patient from                      diagnosis. Br J Oral Maxillofac Surg. 1993;                                                    usually ranges between:
                                                        31:318-320.                                                 dentally.
unnecessary treatment and unwar-                    12. Scuibba JJ, Regezi JA, Rogers RS III. PDQ                b. painless swelling.
                                                                                                                                                          a.   3 to 5 mm.
ranted procedures. !                                    Oral Disease: Diagnosis and Treatment.
                                                                                                                 c. bulging of the jaw.
                                                                                                                                                          b.   1 to 3 mm.
                                                        Lewiston, NY: BC Decker; 2002.
                                                    13. White SC, Pharoah MJ. Oral Radiology:                                                             c.   3 to 5 cm.
                                                                                                                 d. painful swelling.
                                                        Principles and Interpretation. 5th ed. St Louis,                                                  d.   1 to 3 cm.
                                                        MO: Mosby; 2003.
1. Stafne EC. Bone cavities situated near the
   angle of the mandible. J Am Dent Assoc.
   1942;29:1969-1972.                                                                                      4. Incidence rate of Stafne bone
2. Karmiol M, Walsh RF. Dental caries after         Acknowledgment                                                                                  8. Which of the following tech-
   radiotherapy of the oral regions. J Am Dent                                                                defect is nearly:                        niques are useful in diagnosing
                                                    Special thanks to Dr. Brian Cooper,
   Assoc. 1975;91:838-845.                                                                                       a.   0.4%.                            the Stafne bone cyst?
3. Buchner A, Carpenter WM, Merrell PW, et al.      oral surgeon for diagnosing the case,
                                                                                                                 b.   4%.                                 a. periapical x-ray
   Anterior lingual mandibular salivary gland       and Dan D’Amoure, RT, for provid-
   defect. Evaluation of twenty-four cases. Oral                                                                 c.   40%.                                b. panoramic x-ray
   Surg Oral Med Oral Pathol. 1991;71:131-136.      ing the CT scans.
                                                                                                                 d.   0.1%.                               c. cone beam CT imaging
4. Howe GL. “Haemorrhagic cysts” of the
   mandible. I. Br J Oral Surg. Jul 1965;3:55-76.                                                                                                         d. all of the above
5. Howe GL. “Haemorrhagic cysts” of the
   mandible. II. Br J Oral Surg. Nov 1965;3:
6. Huebner G, Turlington EG. So-called traumat-     Dr. Ohanesian is in private practice in
   ic (hemorrhagic) bone cysts of the jaws.         Anaheim, California. He is a Fellow of the
   Review of the literature and report of two       Academy of General Dentistry and the
   unusual cases. Oral Surg Oral Med Oral           International Congress of Oral Implantolo-
   Pathol. 1971;31:354-365.                         gists, and is an Associate Fellow of the
7. Shafer WG, Hine MK, Levy BM. A Textbook of       American Academy of Implant Dentistry. He
   Oral Pathology. 3rd ed. Philadelphia, PA: WB
                                                    can be reached at drohanesian@vinet.com.
   Saunders; 1974:33.
8. Richard EL, Ziskind J. Aberrant salivary gland                                                          Continuing our
                                                    Disclosure: Dr. Ohanesian is not affiliated
   tissue in mandible. Oral Surg Oral Med Oral
   Pathol. 1957;10:1086-1090.                       with NewTom Dental and has no financial
                                                                                                           “Journey of Excellence”
9. Wolf J. Bone defects in mandibular ramus         interest in the company.
                                                                                                                                                                  FEBRUARY 2008 • DENTISTRY TODAY

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