This case report describes a scenario where a 14-year-old patient during orthodontic treatment at Solihull Hospital, West Midlands, presented with a rare soft tissue orthodontic complication. On routine examination, the spring coil from the orthodontic appliance was found to be located in the parotid gland duct. This was extracted by the oral and maxillofacial team at Solihull Hospital. The patient was followed post-operatively for any signs of sialadenitis, sialolithiasis and strictures. After 3 years of follow up, no post-operative complications were noted.
CPD/Clinical Relevance: Soft tissue and orthodontic complications are common, usually due to trauma from sharp components. Clinicians should be aware of complications that can also occur.
Article
Owing to the functional and structural features of the oral cavity, foreign bodies are rare. Additionally, because of the small components of orthodontic appliances, great care is taken in their design and placement.
Patients presenting with pain and swelling over the parotid gland usually have infective or obstructive sialadenitis. Obstructive sialadenitis may be due to calculi, fibromucinous plugs, duct stenosis, foreign bodies, anatomical variations, or malformations of the duct system leading to a mechanical obstruction associated with sialolithiasis. Sialolithiasis accounts for 66% of obstructive salivary disease.1 Strictures and kinks are the second most frequent cause of obstructive sialadenitis and involve the parotid duct in 75.3% of cases.1
Foreign bodies causing obstructive parotid sialadenitis are extremely rare. Only a handful of cases of foreign bodies in the parotid gland have been reported, and most were penetrative foreign bodies from the skin.
This case gives an example of a foreign body found within the parotid gland duct, associated with an orthodontic appliance.
Case report
A 14-year-old female patient who was asymptomatic, presented with a spring coil lodged in her parotid duct. She had a class II division I malocclusion. The treatment plan that she was undertaking, consisted of arch expansion and full upper and lower orthodontic fixed appliance treatment. Part of this treatment involved the use of a spring coil to distalize the upper molars using a temporary anchorage device in the palate (Figure 1).
Figure 1. (a–c) Images taken on examination of spring coil dislodged in parotid duct.
On a review appointment, her clinical examination revealed that the spring coil on the right side of the upper appliance was no longer in situ. It had been dislodged and was now in the patient's right side parotid duct opening. (Figure 2) On further questioning the patient noted that this had occurred 2 weeks previously while on an overseas holiday.
On further examination, no pus was seen, no parotitis, and salivary flow into the oral cavity appeared be of normal composition and flow. The spring coil was extracted carefully from the duct, avoiding any soft tissue damage to the duct. In other circumstances, if the foreign body was located deeper in the duct, retrieval of the foreign body could be achieved with sialadenoscopy. However, no imaging was required to locate the spring coil in this case report.
The patient was reviewed 6 weeks following the removal of the foreign body, with unremarkable symptoms.
Discussion
Foreign bodies in the parotid gland are infrequent. Limited research and few cases have been reported.
Orthodontic soft tissue complications often occur owing to trauma caused by the components of the appliance. Most commonly seen on the buccal mucosa and labial aspect of teeth. This is a case of an unusual orthodontic and soft tissue complication in the oral cavity.
First-line imaging used to examine parotid gland swelling is a CT scan. This is commonly used for the detection of causes of tumours, ductal anomalies, mucus plugs, sialadenitis, sialolithiasis. Standard radiography is seldom used as it can only detect radio-opaque bodies and is not helpful in cases of abscess and tumours. In other cases, ultrasound radiography or sialography can be performed for obstructive cases. In this case, no imaging was required to locate the foreign body.
Complications that could occur include parotid duct obstruction and stricture, preventing the flow of saliva through the duct into the oral cavity. This can result in further symptoms such as: pain, swelling and parotitis (enlargement of the parotid glands) and dry mouth. In some circumstances obstructive parotid sialadenitis may lead to dental caries and further dental symptoms.
In order to prevent this complication from recurring, guidelines at Solihull Hospital recommend that clinicians leave an approximately 3-mm long arch wire at the distal end of the molar attachment, with the end looped over, to prevent the coil spring from being dislodged from the archwire once activation has been achieved.
In this case, the retrieval of the spring coil proved to have minimal complications. In certain cases, post-operative complications of parotid duct surgery can include: nerve injury (including facial nerve palsy and Frey's syndrome), ductal strictures, swelling and xerostomia.
Conclusion
Stenson's duct obstruction is commonly caused by strictures or calculi; however, in this unusual situation, a foreign body from the patient's orthodontic appliance was found in the parotid duct. This case demonstrates that upper spring coils could benefit from a mechanical feature to prevent this from occurring, as other serious complications could occur, such as inhalation.
