From Volume 42, Issue 6, July 2015 | Pages 580-582
This paper describes a case of a 13-year-old patient with a systemic hypersensitivity reaction to orthodontic treatment. Her allergy was investigated resulting in a provisional diagnosis of pressure urticaria. The aetiology, diagnosis and clinical management of allergic reactions to dental procedures are discussed.
A 13-year-old girl was referred to her local hospital orthodontic department by her general dental practitioner. Her presenting complaint was that she was unhappy with her crooked teeth. Her medical history revealed a history of mild asthma, well controlled with Salbutamol prn inhaler and Becotide MDI. She appeared to be fit and well.
Her relevant dental history included surgical removal three years previously of an unerupted supernumerary tooth from the maxillary midline, associated with an impacted maxillary left central incisor. The surgical treatment had proceeded uneventfully and the central incisor had erupted spontaneously within the year following surgery. Orthodontic examination revealed a Class II division 1 occlusion with a severely crowded maxillary arch (Figure 1). Panoramic radiography revealed no abnormal tooth or bony pathology.
The orthodontic treatment plan was to correct her malocclusion with a combination of an upper removable appliance initially, using headgear for anchorage reinforcement. With good compliance established, the extraction of four first premolars and upper and lower fixed appliances were planned. She co-operated well with the removable appliance and headgear wear, and she was therefore referred to her dental practitioner for the extraction of all four first premolars. One day after the extractions, she attended the hospital Orthodontic Department as an emergency patient, complaining of severely swollen lips. On examination, her lips were inflamed, oedematous and crusting (Figure 2). The swelling was not associated with any itchiness and there was no swelling elsewhere. To investigate this unusual reaction to extractions she was referred to the hospital's Accident and Emergency Department. The diagnosis at this time was ‘trauma-induced oedema following dental extractions’ and, following subsequent spontaneous subsidence of her symptoms within the next few hours, no active treatment was instigated. There were no further episodes of swelling at this time and it was decided to continue her orthodontic treatment.
She continued to wear her headgear during the levelling and alignment with fixed appliances and, on her fifth visit for adjustment of her fixed appliances, space closure was started using elastomeric chain. She was given intermaxillary elastics to wear full-time.
One day later, she attended the Orthodontic Department as an emergency patient, complaining of severely swollen gums. She gave a history of sudden swelling which had started a few hours after her orthodontic appointment.
On examination, the gingival margins in both the upper and lower arches were swollen and oedematous. It was suspected that she could be suffering from a delayed Type IV hypersensitivity reaction to latex and a decision was taken by the orthodontist to avoid use of any latex products1 during investigation immediately. The latex components on her fixed appliances were removed that day and active space closure was temporarily discontinued. We referred her to her general medical practitioner to arrange urgent investigation into a possible allergy. Prophylactic measures included the use of non-latex gloves, omission of latex components on her fixed appliances (intermaxillary elastics, elastomeric chain and modules) and arranging to see her first in the morning to decrease the latex exposure occurring through the treatment of other patients.1
However, whilst the medical investigation proceeded, she continued to suffer episodes of oedematous lips and gingivae following adjustments to her orthodontic appliances. The lip and gingival swelling happened one hour after orthodontic adjustments; it was self-limiting and subsided within approximately two hours, with no medication used. An alternative diagnosis of a Type IV cell-mediated delayed hypersensitivity reaction to nickel was being considered and, therefore, precautions were planned in order to reduce, as far as possible, the use of archwires with high nickel content and the omission of nickel active components, such as nickel-titanium closing springs.2 Her headgear wear was terminated at this point.
When the investigations for latex allergy and nickel allergy proved to be negative, the patient was referred to the hospital's dermatologist, who carried out further tests. Initial blood test results appeared to suggest a possible reduction in her C1 esterase inhibitor levels.3 She was therefore referred to the immunologist's allergy clinic at the university hospital for further investigations and for advice as to whether she would require medical treatment.
Subsequent skin prick and blood tests revealed her C1 inhibitor levels to be within normal limits, but her histamine levels were found to be raised.
There are various causes of hypersensitivity swellings in the facial area (Table 1).
| Types of angioedema | Description |
|---|---|
| Acute allergic | Type I hypersensitivity |
| Drug-induced | Induced by ACE inhibitors |
| Hereditary | C1 esterase inhibitor deficiency |
| Acquired | Acquired angioedema Type I |
| Pressure (Contact) Urticaria | Occurs through contact or when pressure is applied to the skin |
A diagnosis of pressure or contact urticaria was made by the immunologist. The patient was advised to use Loratadine 10 mg orally the night before her orthodontic appointments and a dose on the day of the procedure. This successfully prevented the lip and gingival swelling. Her orthodontic treatment was somewhat delayed owing to the necessity of stopping tooth movement during the initial investigations, but she completed her treatment after two and a half years and suffered no further episodes of lip or gingival swelling since the anti-histamine treatment was started.
Urticaria can affect up to 20% of the population.4 It is characterized by acute development of itchy wheals or swellings5 in the skin owing to increased local vascular permeability. The pathogenesis of urticaria involves a Type I hypersensitivity reaction which involves degranulation of mast cells releasing their inflammatory mediators (including histamine) which, as well as local inflammatory reaction, leads to an increase in vascular permeability. There are various causes of Type I hypersensitivity (Table 2). The patient may present with a history of cutaneous swellings and wheals which may occur over a few minutes but last for several hours. The lesions are normally, but not always, itchy and erythematous. Severe urticaria may present with angio-oedema, which may include swelling around the eyes, lips and hands. This may be life-threatening if the oedema involves the larynx. The diagnosis of urticaria is based on the history and clinical features. The treatment of this disease is based on prevention and, for the treatment of idiopathic cases, is based on treating with anti-histamines (eg cetirizine or loratadine).
| Aetiology | Type |
|---|---|
| Allergy | Drug allergy: penicillin, aspirin |
| Infection | Viral infections |
| Cold | Cold urticaria |
| Stress or heat | Cholinergic urticaria |
| Sunlight | Solar urticaria |
| Water | Aquagenic urticaria |
| Pressure/skin contact | Pressure/contact urticaria |
Delayed pressure urticaria follows after a pressure stimulus with swelling, which can peak around 6–9 hours following a delay of a few hours.6 Although the pathogenesis of pressure urticaria is unknown,6 it still shows the similar characteristics of generalized urticaria.7 There are many variants of delayed pressure urticaria which range from the mild to the more severe bullous type.8
It would appear that this patient suffered from oedema caused by the normal handling of her oral tissues during dental procedures. This was initially associated with the dental procedure to extract her teeth and subsequently through the handling forces associated with orthodontic procedures to adjust her appliances. Swelling caused by allergy to handling during orthodontic treatment is rare and this is the first reported case. Urticaria is normally an immediate antibody mediated allergic response occurring within minutes or hours after direct skin or mucosal contact with an allergen.
The majority of patients treated in orthodontic practice are children and adolescents who are medically fit and well. If a Type IV delayed hypersensitivity is suspected during orthodontic treatment, it is essential to instigate preventive procedures and to liaise with the appropriate medical staff whilst the patient is investigated. Type I immediate allergic reactions range from contact urticaria to full-blown anaphylaxis; hence the need for extensive investigation to establish the cause and its treatment. The aim is to reduce, or ideally prevent, the occurrence of serious complications from an unusual medical condition.
