ClinicalRadiology(1993) 47, 424-425
Soft Tissue Neck Radiography for Displaced Dental Prostheses B. M U C C I a n d T. E Y R E
Department of Diagnostic Radiology, West Cumberland Hospital, Hensingham, Whitehaven, Cumbria Modern dental prostheses continue to be made of acrylic resins which can be difficult or impossible to recognize by conventional radiography. We discuss the difficulties that can arise and the recognition of such objects in the neck using three illustrative cases. Mucci, B. & Eyre, T. (1993). Clinical Radiology 47, 424-425. Soft Tissue Neck R a d i o g r a p h y for Displaced D e n t a l Prostheses
Accepted for Publication 21 January 1993
M a n y m o d e r n dental prostheses are made of acrylic plastics which are difficult to visualize on plain radiographs. This has long been u n d e r s t o o d by the dental profession b u t is less well-recognized in medical practice. We present thr~e cases which illustrate the problems of diagnosis when such dental materials are inhaled or swallowed. The n o r m a l soft tissue neck r a d i o g r a p h presents a wide range o f radiographic densities. It is i m p o r t a n t that radiologists are aware of the various presentations of such foreign bodies a n d it is vital that practitioners in the Accident D e p a r t m e n t realize the limitations o f radiographic diagnosis.
CASE R E P O R T S Case 1. An elderlyman presented to the Accident Department having fallen asleepat home wearing his dentures. On waking he could not find his dental plate and could feel 'something sticking in his throat.' A plain soft tissue radiograph of the neck revealed an abnormal opacity of soft tissue density above the level of the epiglottis (Fig. 1). This was removed using direct vision and proved to be a plastic dental plate. The patient made a full recovery. Case 2. An adolescent male presented to the Accident Department after waking up with a choking sensation followinga drinking party. He had lost a dental plate containing two false teeth. Plain soft tissue radiographs of the neck revealed some abnormal gas density areas in the soft tissues of the post-cricoid region (Fig. 2). A barium swallowwas performed which revealeda fillingdefect in the upper oesophagus (Fig. 3). Under oesophagoscopy a dental plate was removed with some difficulty.The patient made an uneventfulrecovery. Case 3. A middle-agedman fell asleep after six pints of beer. When he awoke he was 'choking' and his dental plate with four teeth was missing. He attended the Accident Department where plain radiographs of the neck, showed no abnormality. He was referred to the Ear, Nose and Throat Department and on pharyngoscopy, a dental plate was found just below the cricopharyngeus and was removed. He made an uneventful recovery.
Fig. 1 - A lateral radiograph of the neck shows an abnormal opacity at the level of the hyoid bone.
DISCUSSION It was recognized as early as 1945 [1] that acrylic plastics were difficult to visualize o n plain radiographs. Over the years dentists a n d otolaryngologists have reported a n u m b e r o f clinical cases where visualization
Correspondence to: Dr B. Mucci, Department of Diagnostic Radiology, West Cumberland Hospital, Hensingham, Whitehaven, Cumbria CA28 8JG.
has been problematical [2-4]. Some a u t h o r s have d e m o n strated the successful use o f c o m p u t e d t o m o g r a p h y in detecting acrylic plastic in the p h a r y n x [5,6]. A n u m b e r of workers have suggested that r a d i o p a q u e substances should be i n t r o d u c e d into dental plates [7-9]. A t present, such measures have n o t been widely accepted. The n o r m a l calcified structures in the neck can make the diagnosis of even o p a q u e objects difficult [10,11]. The clinical i m p o r t a n c e of inhaled a n d ingested dental plates c a n n o t be over-emphasized. D e a t h [3] a n d other
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Fig. 2 - A lateral radiograph o f the neck shows abnormal lucent areas in the pre-vertebral space at the level o f vertebra C6 and C7.
Fig. 3 - A lateral radiograph from a barium swallow series shows a filling defect in the barium column caused by a foreign body at the postcricoid level.
serious complications of asphyxia [12] can result. In addition, they can be mistaken for soft tissue tumours [5]. Our cases illustrated the range o f appearances which may be seen on radiographs. Plain radiography can only be an adjuvant to diagnosis. Barium studies can be of value and endoscopy should always be available if radiographs do not demonstrate the object. In longstanding cases, even endoscopy can miss the foreign body and CT can sometimes identify such foreign bodies and help differentiate them from other soft tissue masses [5]. Radiologists must be aware of the potential pitfalls as should those interpreting radiographs in the Accident Department.
3 Adelman HC. Asphyxial deaths as a result of aspiration of dental appliances: a report o f three cases. Journal of Forensic Sciences 1988;33:389-395. 4 Knowles JEA. Inhalation o f dental plates - a hazard of radiolucent materials. Journal of Laryngology and Otology 1991; 105:681-682. 5 McLaughlin M G , Swayne LC, C a r u n a V. Computed tomographic detection of a swallowed denture. Computerised Medical Imaging and Graphics 1989;13:161 163. 6 Newton JP, Abel RW, Lloyd CH, Y e m m R. The use of computerised tomography in the detection of radiolucent dental material in the chest. Journal o f Oral Rehabilitation I987;14:193-202. 7 Hutchison A C W , Witwater DDS. Radiopaque acrylic resin. British Dental Journal 1947;82:167. 8 Bursy DC, Webb JJ. Incorporation of radiopaque materials into denture plastics. US Armed Forces Medical Journal 1960;11: 561-566. 9 Chandler HH, Bowen RL, Paffenbarger GC. The need for radiopaque dental base materials: a review of the literature. Journal of Biomedical Matter Research 1971;5:245-252. l0 Muroff LR, Seaman WB. Normal anatomy of the larynx and differential diagnosis o f foreign bodies. Seminars in Roentgenology 1974;9:267. I l McDonald LR, Pogrel MA. Calcification of the cricoid cartilage mistaken for a foreign body. Journal of Oral and Maxillofacial Surgery 1992;50:62-63. 12 Valori RM, Reelere J. Impacted dentures mimicking brain stem stroke in a conscious patient. British Medical Journal 1985;290:1413.
REFERENCES
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