Word Doc

Question 1

You are shown a cast with an upper Co/Cr framework in place.
- What areas on the upper and lower that give tooth borne support?

Answer 1

• Upper = hard palate and residual ridge
• Lower = buccal shelf, residual ridge and retro-molar pad

Question 2

• Define Kennedy classifications

Answer 2

• It is an anatomical classification that describes the number and distribution of edentulous areas present.
• Class I = bilateral free end saddle
• Class II = unilateral free end saddle
• Class III = unilateral bounded saddle
• Class IV = anterior bounded (crossing the midline)

Question 3

• What function does the palatal extension provide?

Answer 3

• It provides increased mucosal support as a larger surface area is covered which can create a greater seal.

Question 4

• Why do we place rest seats (present on 12)?

Answer 4

• It provides bracing on anterior teeth and indirect retention

Question 5

• Why would a rest seat be placed on the 16?

Answer 5

• To provide direct retentive elements to work in a planned manner and reciprocation further more offering further support by preventing the movement of the RPD towards the mucosa.
• Rest seats can be used for bracing and reciprocation

Question 6

• What are the different types of clasps for premolars?

Answer 6

• Gingivally approaching I-bar clasp

Question 7

• What are the different types of clasps for molars?

Answer 7

• Occlusally approaching single arm clasp
• Occlusally approaching circumferential clasp
• Occlusally approaching ring clasp

Question 8

• Why would framework not extend to the anteriors and gingival margin clearance and what is the benefit of not doing this?

Answer 8

• Less mucosal coverage, making it easier to clean the gingival tissues, less irritation and better compliance.

Question 9

• What impression materials are used for primary impressions in complete denture cases?

Answer 9

• Impression compound which is a non-elastic impression material
• Alginate which is an elastic irreversible hydrocolloid impression material

Question 10

• What are the constituents of alginate and green stick?

Answer 10

• Alginate – calcium sulphate, zinc oxide, sodium phosphate
• Green stick – carnauba wax, talc, stearic acid

Question 11

• Why would a tooth have Impression compound placed on it?

Answer 11

• You can record a single tooth crown preparation using green stick and the copper ring technique

Question 12

• Identify anatomical features on edentulous arches

Answer 12

Refer to notes.

Question 13

• What is an RPI?

Answer 13

• It is a stress relieving clasp system which is used in free end saddle designs to prevent stress on the last abutment tooth and can also provide reciprocation.

Question 14

• What is the mechanism of action of an RPI?

Answer 14

• The rest mesially acts as an axis of rotation. As the proximal plate and I bar rotates downwards and mesially around the axis of rotation during occlusal load. The I bar and proximal plate disengage from the tooth/undercuts, thus avoiding potentially traumatic torque.

Question 15

• What are the causes of denture stomatitis and loose dentures?

Answer 15

• Immunosuppression; diabetes, HIV
• Poor dental hygiene
• Poor denture hygiene – wearing dentures over night and not cleaning dentures appropriately
• Trauma from ill fitting dentures
• Xerostomia
• Systemic steroid use
• Broad spectrum antibiotic use
• High carbohydrate diet

Question 16

• What microbes are involved in denture stomatitis?

Answer 16

• Candida sp. – Candida albicans, Candida tropicalis
• Staphylococcus species – Staphylococcus aureus, staphylococcus epidermidis

Question 17

• What is the initial treatment plan? Denture stomatitis

Answer 17

• Local measures:
  Brush the palate daily and brush the denture after eating with soft brush
  Clean denture thoroughly by soaking in CHX mouthwash or sodium hypochlorite for acrylic for 15 minutes x2 daily)
  Rinse mouth out x2 daily with CHX mouthwash
  Leave dentures out as often as possible and don’t wear over night
  Smoking cessation
  Rinse after inhaler use
  Referral to GDP if suspected underlying medical condition
• Dentures adjustment:
  Ensure dentures are adjusted, relined or a new set of dentures are made as these are currently loose and I’ll-fitting which can contribute to the problem
  Prescribe a tissue conditioner for underneath the denture
• Drug treatment if required:
  Systemic Fluconazole (not if patient is on warfarin or statins) - Fluconazole capsules 50mg Send: 7 capsules Label: 1 capsule daily
  Topical miconazole: Miconazole oromucosal gel 20mg/g , Send: 80g tube , Label: apply a pea sized amount to fitting surface of upper denture after food four times daily.
• Advise: patient should continue to use for 7 days after lesions have healed

Question 18

2 topical agents that can be used for denture stomatitis treatment

Answer 18

• Miconazole oromucosal gel 50mg/g
• Nystatin oral suspension 100,000 units/ml

Question 19

• What would you see on the occlusal surfaces of this patient’s teeth? Denture stomatitis

Answer 19

• Erosion due to the steroid inhaler use
• Patient should rinse mouth out after use
• We can place fluoride varnish on the teeth to help protect them and reduce sensitivity

Question 20

. Patient presents unable to tolerate new dentures having worn the old ones for 20 years, the have become loose over past 18 months and this is why they were replaced

• What can be the differences between the old and new dentures?

Answer 20

• OVD May have changed
• Path of insertion may have changed
• Flange extension can be different
• Palatal extension can be different
• Tooth shade and shape may be different
• Tooth wear may have occurred over time

Question 21

Patient presents unable to tolerate new dentures having worn the old ones for 20 years, the have become loose over past 18 months and this is why they were replaced. - What method could be used to make dentures that he could tolerate?

Answer 21

• Replica technique

Question 22

• What 2 methods can dentists use to improve fit of loose dentures?

Answer 22

• Reline – soft or hard lining material
• Rebase
• Remake dentures

Question 23

• Identify a feature that may cause problems on a patient’s palate

Answer 23

• Tori on the palate
• High arched palate

Question 24

• What 3 things should be checked at the try in stage?

Answer 24

• Extensions
• Retention and stability
• Occlusal plane
• Occlusion (RVD, OVD and freeway space)
• Appearance (Position of the teeth, shade and shape)
• Speech (phonetic tests)

Question 25

A patient recently underwent an extraction of teeth 15 and 16. They arrive 3 months post extraction and request a cobalt chrome partial denture.
- What are the edentulous classifications for maxilla?

Answer 25

• Atwood, Cawood and Howell Classification
• Class I = pre extraction (dentate)
• Class II = post extraction
• Class III = rounded ridge, adequate height and width (broad alveolar process)
• Class IV = knife edge ridge, adequate height, inadequate width
• Class V = flat ridge, inadequate height and width (no alveolar process)
• Class VI = depressed/submerged ridge with varying degrees of basal bone loss, that may be extensive but follows no predictable pattern.
• IV, V and VI are all poor ridges

Question 26

• Outline a denture design to replace 15 and 16

Answer 26

Refer to Q24

Question 27

• Define retention

Answer 27

• Resistance to displacement in a vertical direction
• Tested by pulling vertically on anterior teeth

Question 28

Define indirect retention

Answer 28

• Resistance to rotations displacement of the denture

Question 29

Patent presents requiring RPD with teeth present 34,33,32,31,41,42,43,44,47,48
- Design an RPD and label supportive and retentive components

Answer 29

Refer to Q30.

Question 30

• What features provides indirect retention

Answer 30

• RPI systems on 34 and 44
• Minor connections to the 32 and 42

Question 31

. Patent presents requiring RPD with teeth present 34,33,32,31,41,42,43,44,47,48

Answer 31

• Lingual bar made from CoCr assuming there is 8mm clearance from gingival margin to floor of mouth for major connector to be paced (3mm from gingival margin; 4mm for the bad and 1mm above raised functional depth of floor of mouth).