Clinical Protocol for Removable Partial Dentures by jeq15539

VIEWS: 0 PAGES: 31

									   Clinical Protocol for
Removable Partial Dentures
Diagnosis & Treatment Planning

  • Gather diagnostic info
  • Make preliminary impressions
  • Pour diagnostic casts
Mounting Diagnostic Casts

• If required:
  – Extruded teeth
  – Severe attrition
  – Insufficient interarch space
  – Deep overbite, etc.
• use Semiadjustable Articulator
      Formulate Treatment Plan
• Overall Treatment Plan
• Specific RPD Treatment Plan
  – Select abutments, direct retainers
  – Major connectors
  – Position of rests, g.p., bracing &
    retentive arms
                  Critical!!!
• When RPD is part of treatment:
  – Draw design on surveyed cast
  – Design approved before any treatment started:
     • Affects direct restorations
     • Can influence need for/preparations for crowns
     • Insures RPD can be completed successfully
     • Survey, tripod, heights of contour
Formulate Treatment Plan

• Discuss with instructor prior to
  discussing with patient
• Provide rationale for design
Final Impressions for Partial
         Dentures

 • Framework Impression
 • Altered Cast Impression
         Framework Impression

Border Molded Custom Tray
 – Tray that is made for patient
 – Mold tray periphery with
    thermoplastic compound
Framework Impression

  • Material of Choice
    – Polyvinyl Siloxane
          Framework Impression
• Polyvinyl siloxanes
  –   Excellent dimensional stability
  –   Good tear strength
  –   No taste
  –   Glove contamination
  –   Relatively hydrophobic -
      improved
Prior to the Final Impression

 • No plaque or calculus
 • Healthy soft tissues
 • Initial therapy complete
  Prior to the Final Impression
• Make alginate impression to check:
  – Guiding planes
  – Rest seats
  – Retentive areas
  – Heights of contour
         Framework Impression
• Syringe low viscosity material
  – Around abutment teeth
  – Over occlusal surfaces
• Use care in rest seats
• Do not over fill trays -
  overextension
          Framework Impression

• Medium viscosity in tray
  – Increased filler content
      • less shrinkage
  – Less displacement of soft
    tissues than high viscosities
      Evaluating the Impression
• Absence of Significant Voids
  – Any area where metal
    contacts abutment (e.g.
    rests, minor connectors)
  – Any area where major or
    minor connectors contact
    soft tissue
    Evaluating the Impression

• Peripheries well defined
• Accurately records supporting tissues
• Allows for all elements of design
      Evaluating the Impression

• Mandible
  – Measure FGM to floor of
    mouth
  – Record measurements
  – Transfer to cast - inferior
    framework border
      Evaluating the Impression

• No significant areas of
  “burn through”
  – Border molding not covered
  – Displaces the tissue
  – Change in contour caused by
    the border molding
Evaluating the Impression

• Impression integrity
  – No significant tears
  – Not separated from tray
Evaluating the Impression
• Critical Anatomy Recorded
  – Vestibular depths
  – Hamular notches (marked)
  – Vibrating line (marked)
  – Retromolar pads
  – Frenal attachments
  – Floor of mouth (measured)
Preparation for Impression
• Practice inserting & removing tray
• Dry tissues
     Preparation for Impression
• Block out
  – large embrasures
  – bridge pontics
• Don’t cover occluding or framework surfaces
   Preparation for Impression

• Teeth must be DRY for wax to stick
   Don’t Reseat Impression

• Won’t fully seat over undercuts
        Framework Impression

•   Box & pour impression
•   Survey & tripodize
•   Draw design
•   Send to Lab with Work
    Authorization for
    framework fabrication
                     Master Cast
•   Pour in improved dental stone
•   Type IV (Silky Rock)
•   Vacuum mix stone
•   Allow to set at least 1 hour
    – strength to resist fracture
                Master Casts

• No significant bubbles or
  flaws
• Teeth not fractured from cast
• Includes all anatomical
  surfaces of final impressions
• Includes 3-4 mm. land area
                Master Cast
•   Base parallel ridge
•   12 mm (.5”) thick (minimum)
•   Evidence of a dense stone surface
•   Clean & well trimmed (keep wet while
    trimming)
          Pour Secondary Cast

•   Draw design on secondary cast
•   Checked/corrected with instructor
•   Correct design on 2nd cast
•   Send to lab with 1st poured cast
    – lab will transfer the design to this cast
      RPD Protocol Summary
1.   Diagnosis, Treatment Plan, Hygiene
2.   Diagnostic Casts
3.   Draw Design & list abutment modifications
4.   Instructor Approval
5.   Abutment modifications
6.   Preliminary impression to check mod.’s
7.   Final Framework Impression
8.   Pour two casts
      RPD Protocol Summary
9.    Draw design on 2nd cast
10.   Instructor approval/corrections
11.   Cast to Lab with 1st pour & prescription
12.   Inspect framework waxup
13.   Framework Adjustment
14.   Altered Cast impression, if needed
15.   Try-in with teeth in wax
16.   Process, deliver to patient

								
To top