PROSTHODONTICS GENERAL

Question 1

1. 3 advantages of replacing missing teeth (1.5) (Summative, 2019)

Answer 1

 Restoration of speech and appearance

 Restoration of masticatory efficiency

 Prevention of collapse of the dental arch and over-eruption of teeth

Question 2

2. 6 main oral problems (3)

Answer 2

• Increased plaque accumulation
  
  • More plaque collects under a lingual plate than a lingual bar
  • Root caries is likely, and it is strongly associated with gingival recession; use gingivally-approaching clasps
  • Generalised inflammation –> denture stomatitis; typically it is demarcated by the outline of the palatal connector
• Direct trauma from components
  
  • For instance, a lingual bar positioned too close to the gingival margin may cause gingival recession
  • Insignificant wear on enamel but there may be more wear on restorative materials
• Transmission of excessive force
  
  • If the denture is supported primarily by the natural teeth, most forces will be transmitted to the alveolar bone through the fibres of the PDL; tensile forces are appreciated
  • If the denture is largely supported by the mucosa, most forces will be compressive and in a restricted area – but the periodontium is not well suited to take on this type of forces
  • Consequences:
    
    • Bone resorption
    • Tooth mobility, especially for horizontal forces
• Occlusal error
  
  • If the premature contact is on a natural tooth –> possible damage to the tooth or its PDL
  • If the saddle bears the brunt of the force of closure –> localized mucosal inflammation and resorption of the underlying bone
  • If the patient attempts to steer the mandible around the premature contact until a more comfortable occlusal position is found, this abnormal closing pattern throws increased demands on certain muscles of mastication –> possible orofacial pain

Question 3

Otto lam is wearing a denture as shown in the picture. He feels pain on biting on the left area under the denture

a. What is the condition of the tooth 13?

Answer 3

Anson: please ask the person who created this question to grow up.

Question 4

Otto lam is wearing a denture as shown in the picture. He feels pain on biting on the left area under the denture

b. 2 Causes of the above condition

Answer 4

Anson: twice

Question 5

4. 16 over erupted why?

Answer 5

 Absence of opposing tooth / force
 Natural eruptive potential of tooth allow continuous eruption out of occlusion