www.sada.co.za / SADJ Vol 70 No. 2 CLINICAL REVIEW < 53 Radiopacities in soft tissue on dental radiographs: diagnostic considerations SADJ March 2015, Vol 70 no 2 p53 - p59 CEE Noffke1, EJ Raubenheimer2, NJ Chabikuli3 SUmmarY Radiopacities in soft tissue in the maxillofacial and oral ACRONYMS region frequently manifest on panoramic radiographs in CAC: calcified carotid plaque various locations and in several sizes and shapes. Accurate CBCT: cone beam computed tomography diagnosis is important as the finding may indicate serious CTC: calcified triticeous cartilage disease states. This manuscript provides guidelines for the GHH: greater horn of hyoid bone interpretation of soft tissue radiopacities seen on dental SHTC: superior horn of thyroid cartilage radiographs and recommends additional radiological views required to locate and diagnose the calcifications. tissue ossification is the formation of mature bone with or INTRODUCTION without bone marrow in an extra-skeletal site. Appropriate Soft tissue radiopacities include calcification, ossification or examples are elongation of the styloid process through foreign objects. The latter are excluded from this manuscript. ossification of the attached ligaments and bone formation Calcification is the deposition of calcium salts in tissue. The in synovial chondromatosis. pathogenesis is based on either dystrophic or metastatic mechanisms. Dystrophic calcification, which comprises Idiopathic calcification involves normal serum calcium the majority of soft tissue calcifications in the head and concentration and healthy tissue, and can as such not be neck region, is the result of soft tissue damage with tissue classified as either dystrophic or metastatic. Examples of degeneration and necrosis which attracts the precipitation this are tumorous calcinosis which presents with calcifica- of calcium salts. The blood calcium concentration in these tions around joints and calcinosis cutis, which manifests patients is normal. Appropriate examples are calcification of in the cutaneous or subcutaneous tissue overlying the jaw a focus of necrosis of tuberculosis, necrotic tumour tissue bones. The latter two conditions are rare and will not be or of atheromatous plaque. discussed further. Metastatic calcification on the other hand results from Dental practitioners are required to identify, diagnose, the deposition of calcium salts in normal tissue in the treat or refer for treatment all pathology identified on a presence of hypercalcemia secondary to metabolic causes radiograph. This paper is aimed at providing practitioners such as hyperparathyroidism and skeletal deposits of with insight into the differential diagnosis of soft tissue malignant disease. Metastatic calcifications are therefore radiopacities seen on dental radiographs. In order to generally spread more widely throughout the body than achieve this, a thorough knowledge of the anatomic dystrophic calcifications which tend to be more localized. structures in the head and neck area is important. Accurate The radiology literature is ambiguous in distinguishing interpretation relies on correct positioning of the head between soft tissue calcification and ossification as the during radiographic examinations as this may influence distinction can often only be made histologically. Soft the location and visibility of soft tissue radiopacities on the radiograph. Most calcifications require no further 1. CEE Noffke: MSc. Head: Radiology, Oral Health Sciences, management, but there are several which, if not identified Sefako Makgatho Health Sciences University, South Africa. and managed appropriately, could have serious health 2. EJ Raubenheimer: DSc. Head: Pathology, Oral Health consequences. Sciences, Sefako Makgatho Health Sciences University, South Africa. ParamETERS faciLITATING accUraTE 3. NJ Chabikuli: MDS. Senior Stomatologist, Unit Radiology, Oral Health Sciences, Sefako Makgatho Health Sciences University, INTERPRETATION South Africa. When radiopacities present as an incidental finding in a Corresponding author soft tissue site, it is of pivotal importance to perform a CEE Noffke: thorough clinical examination which includes history tak- Head: Unit Radiology, Oral Health Sciences, Box D17, Sefako ing and palpation of the respective site. The anatomical Makgatho Health Sciences University, 0204. position, number of radiopacities, shape- and size of the Tel: (W): 012 521 4902/3, (H): 012 460 4408, Cell: 082 889 9406 Fax: 012 5215901, Email: [email protected]. calcifications and their internal structure provide important guidelines for their accurate interpretation (Table 1). 54 > CLINICAL REVIEW Table 1: Location on radiographs and description of soft tissue radiopacities Diagnosis Location on radiographs Periphery, shape and number of lesions Internal structure Elongated styloid Between posterior ramus and cervical Tapering, slender, regular, linear and longer Radiopaque or process and ossified spine , next to- or crossing angle of than 3 cm,1 radiopaque outline outlines more stylohyoid ligament mandible, below and mesial from the radiopaque, may be angle (Figure 1) segmented Calcified lymph nodes Submental, submandibular and cervical Irregular, lobulated, cauliflower-like,3 single Varying degrees of (Figure 2) or multiple, vary in size opacity3 Carotid artery Postero-inferior to mandibular angle,17 Irregular, nodular mass or masses, Radiopaque calcification (CAC) adjacent to the cervical vertebrae, at or curvy- or roughly verticolinear,9,22 irregular close to intervertebral space C3-C419 radiopaque line (s),17 rectangular17 (Figure 3) Sialoliths 1. Submandibular sialoliths: on or 1. Regular but may be irregular if close to Radiopaque, (Salivary stones) below body- and mesial to angle of hilus of gland, smooth, round or oval, frequently laminated mandible, above hyoid bone (Figure single or multiple or stippled according 4 and 5) or on apices of mandibular 2. Small, round or oval, single or multiple to degree of premolars calcification 2. Parotid sialoliths: on upper third of Radiopaque ramus or anterior or posterior of it (Figure 1) Tonsilloliths Mid-portion of ramus12 where dorsum Well-defined, round to oval, irregular, small Radiopaque, cortical (calcified tonsils) of tongue crosses the ramus and angle, and multiple (cluster) or single and larger density often below the inferior alveolar canal (rare) (Figure 6) Myositis Ossificans Anatomic region of muscle (s) of Localized or generalized Radiopaque mastication (Figure 7) Synovial Associated with TMJ13 (Figure 8) Large, globular, single or multiple Radiopaque osteochondromatosis, In soft tissue around mandibular Tumoral calcinosis condyle15 Calcification of Below the terminal portion of greater Elongated, regular process, cord-like, Radiopaque or superior horn of horn of hyoid bone (GHH)9 ,(Figure 9) radiopaque outline may be visible, one outlines more thyroid cartilage and mesial to C3 and/or C4. each side radiopaque (SHTC) Calcified triticeous Between SHTC and GHH, level of C3 Well-defined, smooth, oval,16,17 resembles Radiopaque or cartilage (CTC) and C417 (Figure 9), 2-4 mm wide and a grain, one each side outlines more 7-9 mm in length16 radiopaque Antrolith Most frequently above floor of maxillary Well-defined, smooth or irregular, single Radiopaque, sinus (Figure 10) laminated Rhinolith Nasal cavity Well-defined, smooth or irregular, single Radiopaque, sometimes laminated Although most radiopacities hyoid ligament may mani- are asymptomatic, symp- fest with headaches, pain toms may be helpful in es- with swallowing, yawning tablishing a diagnosis. The and with moving the head stylohyoid process arises laterally, referred tempo- from the inferior surface romandibular joint (TMJ) of the temporal bone and pain or recurrent throat extends infero-mesially to- pain due to impingement wards the pharyngeal wall. of the elongated process Two ligaments (stylohyoid on adjacent structures.1,2 A and stylomandibular) and symptomatic ossified sty- three muscles (stylohyoid, lohyoid ligament is referred stylopharyngeus and sty- to as Eagle syndrome and loglossus) originate from this panoramic radiography Figure 1: Panoramic image (cropped). Figure 2: Panoramic image (cropped). process and together they The radiopaque outlines of an ossified showing a length of 3cm or Several calcified lymph nodes present as are sometimes called the stylohyoid ligament (open arrow), pass- more is sufficient to confirm irregular shaped radiopacities below the “stylohyoid chain”. Ossifica- ing the angle of the mandible, are pres- the diagnosis (Figure 1). lower border of the right mandible. tion of one or more of the ent in this radiograph of a 77-year-old female. A calcification within Stensen’s components of the chain duct of the parotid gland can also be A productive cough or history of tuberculosis may be an begins normally at the sty- seen projecting onto the upper part of indication of tuberculous lymphadenitis with dystrophic loid process and can create the ramus (solid arrow). calcification of lymph nodes.3-5 Calcified lymph nodes are the radiographic image of an elongated styloid process. The asymptomatic (unless secondarily infected) and may be stylohyoid ligament is attached at the lesser horn of the hyoid seen as an incidental finding on a panoramic radiograph bone and therefore stabilizes it. Patients with an ossified stylo- at the anatomic sites where lymph nodes are found www.sada.co.za / SADJ Vol 70 No. 2 CLINICAL REVIEW < 55 (Figure 2).4,5 The patient should be informed of the possible