Week 6

• Implants


  Anchors for prosthetic devices that are fixed to the bone
• Types of implants


  • Subperiosteal
  • Transosteal
  • Endosseous
• Endosseous implants


  • Have the highest success rate
• Subperiosteal implants - 3 stages

  1. Surgical incision to expose bony ridge, impression made

  2. Replica of bony ridge made, metal framework cast

  3. Second incision to insert implant framework

  
• Transosteal implant


  Consists of a horizontal support beam attached to metal rods inserted through the mandible
• Endosseous implants


  Surgically placed into the bone, titanium and titanium alloys are the most common materials
• Titanium


  Lightweight, corrosive resistant, biocompatible material that allows forces to be evenly distributed between implant and bone
• Osseointegration


  Bone grows around and closely adapts to titanium and titanium alloy implants
• Implant fixture designs


  • Cylinder
  • Tapered
  • Textured
  • Vented
  • Ceramic cylinder
• Implant placement and restoration

  1. Two-stage surgical procedure

  2. One-stage surgical procedure
• Cover screw (healing screw)

  Prevents tissue from growing into the screw hole after implant fixture is covered
• Healing abutment


  Allows the gingiva to form a cuff around it
• Immediate-placement surgical procedure


  Tooth is extracted and implant fixture placed directly into new socket

  
• Impression procedures


  • Open-tray impression
  • Closed-tray (transfer) impression
• Implant fixture


  Portion of implant placed in bone to support crown or prosthesis

  
• Abutment


  Attachment to implant fixture that protrudes through gingiva and acts like a tooth preparation
• Impression abutment


  Facilitates orientation of implant analog to cast
• Implant analog


  Used in lab as substitute for implant fixture to make implant crown
• Screw-retained implant crown


  Has occlusal screw-access hole
• Mini-implants


  Placed in sites with minimal bone, used to stabilize dentures

  
• Early implant failure is usually due to failure of bone to integrate with implant
• Crown


  Made to fit the abutment much like a crown is made to fit to a prepared tooth
• When multiple teeth are being replaced

  1. Implant supported fixed bridge

  2. Removable complete denture

  3. Partial denture

  
• Single-tooth implant with a cemented crown

  • Radiograph of fixture in bone and the attached implant abutment
  • Abutment is attached to the fixture by a screw
  • Crown is cemented onto the abutment

  
• Mini-Implants


  • Placed in sites with minimal bone that could not accommodate a conventional implant unless grafting was done
  • Used to stabilize a denture

  
• Implant failure


  • Early failure of an implant is usually due to failure of the bone to integrate with the implant
  • Failure of the implant that occurs after the initial integration is often caused by bacterial infection extending from the peri-implant tissues into the bone, or overloading the implant during function, leading to loss of the supporting bone
• Peri-implantitis resulting in bone loss around the dental implant

  
• Types of bone grafting

  • Autografts – harvested from client's own body
  • Allografts – human bone taken from donors who have donated body parts at time of death (cadaver bone)
  • Xenografts – obtained from animals, usually bovine or porcine
  • Alloplasts – synthetic materials that stimulate new bone
• Allograft


  • cadaver bone in granules and large and small pieces( fresh, freeze dried, demineralized freeze dried)
• Xenograft


  • mineral granules used for bone graft
• Alloplast


  • synthetic bone made from hydroxyapatite bioactive glass, calcium phosphate, calcium sulfate
• Barrier Membranes


  • Thin membrane that prevents fibrous tissue from growing into the site of bone grafting/ prevents the graft material from being lost from the graft site
  • Can be resorbable (collagen) or non-resorbable(teflon)- removed in approx. 3 weeks
• Sinus Lift


  • A surgical procedure that adds bone in the molar & premolar region when: The maxillary sinus has extended into that area
  • Bone has resorbed from the alveolar ridge after teeth were lost
  • Both
• Types of sutures


  • Absorbable - e.g synthetic polyglicolic acid& surgical gut(plain or chromic)
  • Non-absorbable - e.g: silk, polyester fiber, nylon
• Suture Techniques


  • Interrupted sutures
  • Continuous suture
  • Vertical mattress suture
  • Horizontal mattress suture
• Chromic gut sutures


  • derived from animal collagen
• Synthetic polyglycolic acid sutures

  • made from a biodegradable thermoplastic polymer
• Non-absorbable suture


  • made of braided silk
• Bone grafting procedure
• Implant Maintenance - Home Care

  • Customized to client's needs – OSC critical component to implant maintenance
  • A gentle sulcus brush can help maintain the tissue around the implant
  • Interproximal brushes (nylon coated proxy brush)mounted on plastic instead of metal are used for implant maintenance
  • End –tuft brushes when the space between implants is greater