2.3 Down Syndrome
Section I: Clinical Scenario and Dental Considerations
Clinical Scenario
A 48‐year‐old patient attends the dental clinic complaining that his removable upper partial denture is unstable and ‘does not work when eating’. The patient has been given several dentures in recent years but none of them has been successful
Medical History
- Down syndrome
- Atrial septal defect corrected in childhood
- Recurrent respiratory infections
- Mild hearing loss
- Gastroesophageal reflux
- Chronic anaemia
- Hyperuricaemia
Medications
- Budesonide
- Theophylline
- Allopurinol
- Lansoprazole
- Iron and folic acid
Dental History
- Regular dental attender
- Previous dental treatment with local anaesthesia tolerated on numerous occasions without the need for pharmacological adjuncts (calculus removal, extraction, fillings, endodontics, non‐surgical periodontal treatment and prosthetic rehabilitation)
- Three years ago, the patient underwent excision of a maxillary odontogenic cyst (5 × 2.5 cm) under general anaesthesia
- The patient brushes his teeth independently twice a day using a fluoride toothpaste (without supervision)
Social History
- Parents deceased; lives with one of his sisters
- Independent for activities of daily life
- Attends a centre where he participates in cognitive stimulation and craft workshops
Oral Examination
- Very co‐operative
- Lip fissures
- Fissured tongue
- Fair oral hygiene
- Microdontia
- Dental spacing
- Missing maxillary teeth: #14, #15, #16, #17, #21, #22, #23, #24, #25 and #26
- The remaining maxillary teeth have significant gingival recession with cervical exposure and grade 1–2 mobility
- Missing mandibular teeth: #32, #35, #42 and #45 (possibly due to agenesis, based on the findings of previous radiographs)
- Irregular alveolar bone crest in the upper left quadrant, with a considerable bone defect as sequela of the cystectomy (intact mucous coating with a normal appearance) (Figure 2.3.1a)
- Unstable upper partial denture (Figure 2.3.1b)
Radiological Examination
- Orthopantomogram and cone beam computed tomography (Figure 2.3.2) undertaken
- No radiological evidence of recurrence of the odontogenic cyst, but there is loss of bone mineral density
- The only available bone volume for the direct insertion of dental implants identified in positions corresponding to teeth #14 and #26
Structured Learning
- What are lip fissures and what causes them?
- Lip fissures are a frequent finding in patients with Down syndrome (>25%), especially among men, with a peak prevalence in the third decade, and occur preferentially in the lower lip
- Their aetiology is unknown (embryological defects, mandibular prognathism and lip eversion have been implicated)
- In most patients, the lesions coexist with angular cheilitis and are colonised by Candida albicans
- What factors are considered important in assessing the risks of managing this patient?
- Social
- Favourable family environment
- Hearing impairment
- Complications can arise due to other comorbidities associated with Down syndrome (e.g. premature ageing and cognitive impairment)
- Medical
- Respiratory dysfunction
- Fatigue/reduced tolerance for treatment in relation to anaemia
- Corrected atrial septal defect is not associated with risk when delivering dental intervention
- Dental
- Multiple failed attempts at providing removable partial dentures
- Oral hygiene could be improved
- Multiple missing teeth but low caries rate; chronic periodontal disease likely cause of tooth loss
- Prognosis of the remaining teeth guarded
- Implication for success of osseointegrated dental implants
- Gastroesophageal reflux‐related risk of dental erosion
- Anaemia‐related oral side‐effects (pale mucosa, glossitis, oral ulceration)
- Social
- What factors determine the prognosis of the dental implants in this patient (Figure 2.3.3)?
- The available bone volume is limited
- Osteopenia
- Susceptibility to infections (potential defects in neutrophil chemotaxis due to Down syndrome)
- Sub‐optimal oral hygiene and a history of periodontal disease can favour the onset of peri‐implantitis. Ongoing oral hygiene/periodontal support provided due to variable compliance
- Observed higher failure rate: in patients with Down syndrome, 1 in every 5 dental implants fails
- If considering the use of dental premedication/sedation to place dental implants, what additional factors should be taken into account?
- Benzodiazepines should not be prescribed for patients with severe respiratory dysfunction or hypotonia (musculoskeletal effect of Down syndrome)
- Theophylline reverses the sedative effect of benzodiazepines
- Is administering antibiotic prophylaxis before a surgical procedure such as implant insertion justified?
- The corrected atrial septal defect does not justify the prescription of antibiotic prophylaxis for the prevention of bacterial endocarditis
- However, the immunological defects observed in Down syndrome may constitute an indication for administering antibiotics prior to the surgical procedure and for maintaining them in the postoperative period
- What antibiotics should be avoided for this patient?
- The toxicity of theophylline increases with macrolide antibiotics and quinolones