Impression making, provisional restorations and tissue management in fixed prosthodontics .pdf

impression making, provisional restorations and tissue management in fixed prosthodontics Alper Çomut, DMD, DMSc steps in fixed prosthodontics step 1: tooth preparation step 2: provisional restorations step 3: tissue management step 4: impression making Fixed provisional restorations should mimi...

impression making, provisional restorations and tissue management in fixed prosthodontics Alper Çomut, DMD, DMSc steps in fixed prosthodontics step 1: tooth preparation step 2: provisional restorations step 3: tissue management step 4: impression making Fixed provisional restorations should mimic the Final Fixed Partial Denture to be fabricated materials for provisionals Polymethyl methacrylate - acrylic bis-acryl composite resin - luxatemp powder / liquid configuration, self-cure paste / paste dispensed from preloaded syringes longest used material good marginal adaptability good strength good polishability possibility for reline and repair consistent mixture with no air incorporation low exothermic setting reaction, kinder to pulp low shrinkage good marginal fit good strength and abrasion resistance low abrasion resistance high volumetric shrinkage high exothermic reaction free monomer toxic to the pulp more brittle less stain-resistant repair, reline difficulty limited shade availability more costly for anterior and posterior provisionals for anterior provisionals, especially veneers fabrication techniques chair side fabrication - vacuform - putty matrix laboratory fabricated - no-reinforcement - metal or fiber reinforced prefabricated crowns - polycarbonate crowns - bisacrylic crowns block technique why is a provisional restoration important? - Pulpal protection - Positional stability - Occlusal function - periodontal health - Esthetics - template for the final restoration A good provisional restoration should: - Easily cleaned - Nonimpinging margins - Strength and retention - Esthetics Tray Preparation Mandibular Impression Articulation and Wax-up Wax-up Duplication Vacuform Fabrication Vacuform Vacuform Try-in Acrylic Preparation Intraoral Application Proximal and Axial Walls Embrasures Pontic Buccal Surface Occlusal Morphology Occlusal Adjustment Relining Relining Relining Relining Final IFPD Final provisional restoration Cementation key points - Interim Fixed Partial Denture should mimic the Final Restoration - When trimming always Look at the margins - Pencil Mark Proximal Contacts and Margins Before Trimming - Impression in acrylic - Margins Flash with the root - First occlusal anatomy then occlusal adjustment - Relining Must be done following initial margin, proximal contact, axial wall, embrasure and occlusal trimming and occlusal adjustment tissue management goals: to capture the margins of tooth preparation during impression 1. hemostasis prevents bleeding during impression 2. retraction of gingival tissues to expose the margins of tooth preparation hemostasis 1. well fitting margins of the provisionals 2. open embrasures of provisionals 3. good oral hygiene 4. gentile cord packing hemostatic agents 1. epinephrine 0.1 - 8% 2. aluminum chloride 5 - 25% - hemodent ~ retraction - viscostat clear ~ hemostasis 3. ferric sulphate 13.3 - 20% - viscostat ~ hemostasis - astringedent ~ hemostasis 4. zinc chloride hemostatic agents retraction retraction can be mechanical and chemical mechanical retraction is obtained with the retraction cord itself chemical retraction is obtained by a vasoconstrictor agent such as epinephrine retraction retraction techniques one cord technique: remove all cords before impression double cord technique: leave the initial cord in place during impression 1 2 4 5 3 6 key points - cord packing with anesthesia, even if the tooth is non-vital - complete dry environment; no blood, no saliva - hemostasis control by viscostat, cord treatment by hemodent - cord location is next to the margin not the deepest portion of the sulcus - cord visible 360 degrees around the margin