Other Special Considerations

Other Special Considerations
16.1 Allergies

Section I: Clinical Scenario and Dental Considerations

Clinical Scenario

A 20‐year‐old man with cerebral palsy presents for an urgent dental appointment accompanied by his mother. She reports that her son had a severe seizure that morning and hit his face against a cupboard adjacent to his bed. She is concerned that this could have damaged his teeth.

Medical History

  • Cerebral palsy (hypotonic paraparesis)
  • Spina bifida
  • Epilepsy (daily seizures)
  • Aortic valve insufficiency
  • Dorsal‐lumbar scoliosis
  • Allergy to bananas


  • Sodium valproate
  • Topiramate
  • Diazepam

Dental History

  • Fair oral hygiene; toothbrushing twice daily by his care‐giver
  • Patient underwent dental treatment under general anaesthesia 4 years earlier
  • Since then, he has had yearly check‐ups
  • Although the patient is co‐operative, he has moderate dental anxiety resulting in an increase of his involuntary movements

Social History

  • Lives with his parents; attends a day care centre
  • Completely dependent for daily life activities
  • Wheelchair user
  • Non‐verbal; his mother interprets his non‐verbal language and is able to determine when he is in pain

Oral Examination

  • Not compliant for a full oral examination
  • Oral hygiene fair
  • Trauma to the inside of the lower lip observed: 2 cm linear cut
  • #32 grade II mobility but not extruded

Radiological Examination

  • Not compliant for radiographs

Structured Learning

  1. What additional questions should you ask regarding the reported trauma to the face?
    • The patient is a vulnerable young adult as he is unable to look after himself and is dependent on others; as a result, he is unable to protect himself against significant harm or exploitation
    • In view of this, it is important to establish further details of the reported cause of the traumatic event and make further assessments to ensure that there are no other indicators of the patient being at risk, due to either neglect (left unsupervised) or physical abuse (confirm whether there are any other signs/history of trauma)
    • If concerned, it is important to raise a safeguarding alert (it is important to take clinical photographs)
  2. In the case of this patient, you determine that the facial/dental injuries are consistent with the explanation given and the mother has already requested a raised bed rail is fitted on the bed. Following discussion with the patient and his mother, it is agreed that you need to anaesthetise the area of trauma to investigate further. Topical anaesthetic (20% benzocaine) is applied prior to administration of a local anaesthetic injection (2% lidocaine with 1:80 000 epinephrine). A sudden increase in the volume of the lower lip is observed (Figure 16.1.1). What differential diagnoses would you consider for this presentation?
    Photo depicts sudden lip swelling during dental treatment may become a medical emergency (S).

    Figure 16.1.1 Sudden lip swelling during dental treatment may become a medical emergency.

    • Allergic reaction
    • Hereditary angio‐oedema
    • Haematoma due to intravascular injection
    • Subcutaneous/submucosa emphysema related to the use of compressed air is another cause of facial/lip swelling but would not apply in this case
  3. What would be your immediate concern?
    • This rapid presentation of lip swelling should be treated as an emergency situation as it can be life‐threatening, with features of a type I allergic reaction
    • It is important to assess if there are breathing difficulties, abdominal pain, dizziness and/or an urticarial rash
  4. What factors are important for this patient when handling this emergency situation?
    • Social
      • Non‐verbal communication – challenging to confirm with the patient how he is feeling; hence it is essential for his mother to be present to reassure the patient and interpret his non‐verbal communication
      • Wheelchair user – unable to transfer without a hoist
    • Medical
      • Scoliosis may impair breathing further
      • Increased risk of epileptic seizure as the result of the stress generated by this incident
      • Acute complications of aortic regurgitation (uncommon)
    • Dental
      • Emergency management should be the priority with emergency empirical treatment implemented for a type I allergic reaction/angio‐oedema event
      • The mobile #32 may be a risk to the airway if it becomes extruded
      • Avoid the use of any potential allergens (e.g. latex, benzocaine)
  5. What drugs may be prescribed to treat this episode?
    • If the condition is limited to the lips, with no systemic involvement:
      • Monitor closely; if the lip swelling abates, refer to the patient’s physician for allergy testing
      • If there is local support from a physician, H1 antihistamines (e.g. diphenhydramine, chlorpheniramine and hydroxyzine) and/or corticosteroids (e.g. prednisone and methylprednisolone) may be prescribed at the same visit
    • If there are signs of systemic involvement/respiratory distress:
      • Request emergency medical assistance
      • Oxygen in facemask
      • Subcutaneous epinephrine
      • Inhaled salbutamol
      • If there is on‐site medical assistance and the patient stabilises, antihistamines and corticosteroids may also be given
  6. The lip swelling abates and you refer the patient to his physician to arrange allergy testing. It is confirmed that the patient is allergic to latex. What factors in this patient’s medical history increase his risk of latex allergy?
    • Spina bifida (failure of fusion of the neural tube during embryonic development); may be related to repeated exposure to latex, higher incidence of atopy and possible genetic predisposition
    • Allergy to bananas; cross‐reactivity to latex is known
  7. What precautions should be adopted for the next dental visit?
    • Liaise with the physician to confirm if they wish to prescribe prophylaxis with antihistamines and corticosteroids to enable dental treatment
    • Schedule the patient for the first appointment of the day
    • Ensure a latex‐free environment (i.e. use latex‐free gloves, remove any instrumentation, equipment and accessories that contain latex, confirm that the dental local anaesthetic used is latex free)
    • Ensure the surgery is labelled as a ‘latex‐free zone’ to avoid contamination/staff entering without permission
    • All team members to be aware of the implications of the allergy and trained in emergency management

General Dental Considerations

Oral Findings

  • Type I allergy
    • Labial or lingual oedema
    • Perioral urticaria
    • Glottic oedema (anaphylactic shock)
  • Type II allergy
    • Signs of anaemia (mucosal pallor, depapillated tongue)
    • Haemorrhagic lesions (petechiae, ecchymosis, haematomas)
    • Necrotic ulcers
  • Type III allergy
    • Haemorrhagic ulcerative stomatitis
    • Localised haemorrhagic necrotic vasculitis
    • Erythema multiforme (Stevens–Johnson syndrome)
  • Type IV allergy
    • Fixed drug eruption
    • Lichenoid reactions
    • Allergic stomatitis induced by drugs or prosthetic material
    • Granulomatous cheilitis
    • Non‐specific findings such as burning mouth, pain, flaking and xerostomia (Figure 16.1.2)

Dental Management

  • In recent years, the number of allergic reactions related to the dental clinic environment has increased significantly (Table 16.1.1)
  • For the dental team, the most common triggers for allergic reactions are latex, acrylate and formaldehyde
    Photos depict oral manifestations of allergic reactions.

    Figure 16.1.2 Oral manifestations of allergic reactions (types I–IV).

  • For dental patients, it is also important to consider contact allergy to certain metals and resins, as well as hypersensitivity reactions to commonly used drugs
  • Before proposing a dental procedure for a patient with presumed allergies, the allergy diagnosis should be confirmed; the allergen panels selected for analysing hypersensitivity to dental materials vary between countries
  • Once the responsible allergen(s) have been identified, these should be avoided, the requirement for drug prophylaxis should be assessed, and preparations should be in place to manage emergency situations (Tables 16.1.2 and 16.1.3)

Section II: Background Information and Guidelines


Allergy is a hypersensitivity reaction of the immune system during which the system identifies certain substances as harmful which are in fact safe for most of the population. These substances are known as allergens. The most common allergic diseases are allergic rhinitis (hay fever), allergic asthma, urticaria, atopic dermatitis, allergic contact dermatitis and food allergies.

Allergies are the most typical cause of chronic disease in industrialised countries. Worldwide, the rate of sensitisation to 1 or more common allergens is estimated at approximately 40%, with certain underlying conditions known to be more commonly associated with the development of allergies (Table 16.1.4).


  • There are 4 main types of allergic reaction which are mediated in different ways; the risk of developing these is increased in relation to certain predisposing diseases and risk factors

    Table 16.1.1 Allergens with particular relevance to dentistry.

    Only gold members can continue reading. Log In or Register to continue

    Allergen Clinical presentation Characteristics

Stay updated, free dental videos. Join our Telegram channel

Nov 6, 2022 | Posted by in Implantology | Comments Off on Other Special Considerations

VIDEdental - Online dental courses

Get VIDEdental app for watching clinical videos