Prosthetics Revision Clinical Steps

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Prosthetics RevisionClinical Steps
Dr Charles Scola July 2004
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Prosthetics Revision

• Last two weeks we studied
• Dentist / Patient expectations
• The value of an old denture
• A written denture treatment plan
• RVD OVD FS
• Copy Denture Technique
• F/F Clinical techniques
• Overdentures

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Meeting their needs expectations

• What sort of patient are they?
• Easy going or up-tight
• Adaptable or precise
• Accepting or demanding
• Cooperative or difficult
• Asses their attitude personality,
• This is very important in denture tolerance
• NEVER promise what you cannot deliver !

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Your Denture Treatment Plan

• This is your written prescription or recipe
• Without it you will get lost !
• It applies to new or old denture users
• Must be agreed with the patient
• Keeps you on the right track
• Is your record and defense, in case of later
  problems or complaints

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At every stage of treatment

• Check your treatment plan
• Remind your patient of the plan
• Explain what you are doing today
• Measure RVD OVD
• Look at the old dentures compare
• Observe the patient as they talk smile
• Remind the patient of the limitations

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Vertical Dimension

• RVD is always gt OVD
• RVD should remain constant
• whether dentures are worn or not
• Whatever treatment you do
• OVD may be changed by you
• All patients need FS, 2 5mm

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Vertical Dimension
RVD
Freeway space
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Vertical Dimension
0VD
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Prosthetics Revision

• Today we are going to consider
• Partial Denture planning design
• The clinical stages of partial denture
  construction

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Partial Dentures
Please read Dr Ulpee Darbars notes, these are
very good !
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Partial dentures often grow up into full
dentures- why ?
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Partial dentures often grow up into full
dentures- why ?

• Plaque
• Caries, perio disease
• Trauma
• Abrasion, forced gingival recession, tissue
  hyperplasia
• Excessive forces
• Worsens perio disease, bone loss, mobility

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Partial dentures yes or no ?

• So before we rush to make a partial denture, ask
  yourself
• Will it do more harm than good
• Are there safer alternatives
• Have you explained all the pros and cons to
  your patient
• Partial dentures need plenty of maintenance, by
  you and the patient

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Partial Dentures - Benefits

• Appearance
• Face, lips, smile, sexy
• Function
• Chewing, biting, gripping, tearing, kissing
• ? Helps remaining teeth
• Spreads load, prevents tilting, over-eruption
• ? Prepares pt for full dentures
• (Is this rather defeatist)

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Partial Dentures - design

• Must minimize plaque build up and allow pt to
  maintain good oral hygiene
• Needs to avoid soft tissue trauma
• Should support and stabilize the remaining teeth
  without producing excessive occlusal or tipping
  forces
• Avoid your partial denture becoming
• a gum stripper
• an orthodontic appliance !

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Partial Dentures - design

• Retention
• Stops the denture falling out
• Suction, friction, muscular, mechanical (clasps
  etc)
• Resistance or Support
• Stops the denture being pushed in (gum stripper)
• Tissue or tooth borne ?
• Connectors
• Joins the teeth, aids resistance retention
• Make it as patient-friendly as possible
• Refer Dr Ulpees notes on clasps/ rest seats

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Resistance or Support

• Stops the denture being pushed in
• A major cause of trauma to tissues !
• Tissue or tooth borne - Which is better?
• Teeth are made to take occlusal load
• Soft tissues are not !
• The effects of sinking are
• Trauma to gingivae and forced recession
• Damage to mucosa by flanges and connectors
• Denture teeth start to look too short
• Natural teeth may be tilted, intruded or loosened

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Providing Resistance or Support

• Bring the acrylic up over the cingulum of
  anterior teeth,...if the bite allows it !

?
?

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Providing Resistance or Support

• Bring the acrylic up over the bulbosity of
  molars, ....if the bite allows it !

?
?

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Providing Resistance or Support
You may need to cut a rest seat
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Providing Resistance or Support

• Provide metal occlusal rests
• With premolars molars you cannot easily bring
  the acrylic over the occlusal surface, ..but you
  can fit a metal occlusal rest

Your denture will hang off the teeth
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Providing Resistance or Support

• Occlusal rests
• Make the denture tooth borne
• Should be used wherever possible
• Are used on strong teeth
• Need to be positioned carefully
• Can be formed from stiff wire and inserted into
  the arylic

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Providing Resistance or Support
You may need to cut a rest seat
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Providing Resistance or Support
You may need to cut a channel for a clasp This
will also provide support
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Connectors

• Do not pinch the gingivae
• Keep 4mm away
• Do not cause food traps
• Cross the gingival margins mid-tooth only
• Keep the design simple
• Avoid cutting across rugae in palate
• Follow them instead
• Follow anatomical lines if possible

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Partial Dentures - planning

• As soon as you have your study models, and BEFORE
  you take your 2 impressions
• Plan your design, considering all the pros
  cons, and your patients wishes
• You may need to consider
• More extractions
• Hopeless prognosis, deep undercuts
• Conservation
• Reshape opposing teeth,
• Cut rest seats, channels for clasps, guide planes
  
• Remove undercuts, create undercuts

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Guide Planes Occlusal Rests
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Partial DenturesLets try to design a few

• Follow these principles
• Which teeth are to be replaced
• Design connectors and outlines
• Avoid palatine papilla if possible
• Consider undercuts path of insertion
• Provide resistance retention
• Do any teeth need cutting, reshaping, or exo
• Draw on your model write your treatment plan

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Partial Dentures, 2 Imps

• Check your treatment plan
• Cut or reshape any teeth as needed, ?undercuts
• Check your special tray covers all areas that are
  crucial to your design
• Take good alginate impressions, use your finger
• Take your shade
• Check the occlusion, ? take a wax bite, you may
  not need to take MMR using bite blocks

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Partial Dentures, MMR

• Will only be needed if
• Many teeth are missing
• There are free end saddles
• There is no tooth to tooth contact
• The existing occlusion needs to be raised, or
  changed in some way (rare)

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Partial Dentures, MMR

• Check fit and stability of wax blocks
• Trim occlusal levels to follow natural teeth
• If there is tooth to tooth contact, use this
  occlusion unless there is a specific reason to
  change it
• Record bite blocks in centric occlusion
• Mark centre lines

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Partial Dentures, Try - In

• Confirm smile lines and levels
• Agree aesthetics with the patient
• Similar steps to F/F try in
• Assess accuracy of the occlusion
• But also
• Check resistance is occlusion affected
• Check retention - will clasps show
• Hygiene are there food traps
• Soft Tissues any risk of trauma

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Partial Dentures, Fitting

• Try them in gently, never force them
• Adjust carefully to ensure a snug fit
• Check occlusion, ? Tooth to tooth contact
• Check aesthetics, ? Objectives achieved
• Ensure comfort, no trauma
• Teach patient how to fit and remove them
• Dont use clasps as handles
• Give full cleaning maintenance instructions
• Dont wear them 24 / 7, give your mouth a rest

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Prosthetics Revision

• Today we have reviewed
• Partial Denture planning design
• The clinical stages of partial denture
  construction

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That's all for today thank you for listening!