maintenance phase

Question 1

What is the maintenance phase?

Answer 1

Plan from outset
Part of prognosis
Patient understanding of limited life of restorations
Pt time and financial commitments

Question 2

What determines how long something lasts?

Answer 2

Build quality- intra oral assembly (biological substrate and building materials, operator skill set and facilities and time)

Loading- product handling (in/direct loading forces [3-400N], para/functional [bruxism- 1000N])

Environment- bacterial biofilm, constantly wet, temp changes, variable pH, tooth-material interactions

Maintenance- comprehensive purpose designed maintenance schedule, fundamental to survival

Question 3

How should a maintenance plan be given?

Answer 3

Discussed and agreed before finalising treatment strategy
Pt understand implications (time, finances, own health, oral hygiene)

Question 4

What is the Weibull survival curve?

Answer 4

Initially- very high failure rate (catastrophic biological or structural failure)
Eg. Post perforation, inadequate aesthetics, occlusal interface, pulpitis, de-bonding

Then, low grade chronic disease
Eg. Secondary caries, occlusal trauma, periapical periodontitis

Lastly, fatigue related biological structural failure
Eg. RCT, root caries, porcelain chipping, cusp fracture

Question 5

What should you do at review?

Answer 5

Check for new or continuing disease
Check adequacy of existing restorations
Check compliance w maintenance protocol
Determine future recall periods

WHY HAS IT HAPPENED?

Question 6

What kind of technical failure may occur?

Answer 6

Fractured restorations
Marginal breakdown
Tooth fracture
Defective contour
Appearance
Retention failure

Question 7

What is failure?

Answer 7

Unacceptable deterioration
Which is why prognosis needs to be established (INFORMED CONSENT)

Question 8

What is planned maintenance?

Answer 8

Plan for failure where prognosis is guarded- anticipation
Avoid emergencies