Notes from Drs. Marx and Peleg’s (University of Miami) talk on Implants and bone grafting

Dr. Marx's talk on ridge augmentation prior to dental implant placement

Some of my students have asked me to post the notes form this talk…so here it is.  Hope this helps.

Dr. M. Peleg:

  • Always do soft tissue grafting in addition to bone augmentation
  • When you lose bone, you lose soft-tissue & when you lose soft-tissue, you lose bone.
  • As we age, we lose teeth, we end up with a pseudo-class III malocclusion, where the lower jaw is forward of the upper jaw.
  • Tension free primary closure is critical, underscore the periosteum!
  • Implant that is not surrounded by attached gingiva is compromised, even 2mm is better than nothing.
  • Subperiosteal dissection first, then graft. If done in reverse, it will bleed and dilute the bone graft due to hematoma. If you dissect first, it will spontaneously stop bleeding before the bone graft. If the bleeding does not stop in 10 minutes, then there is vessel that needs to be ligated. Metzenbaum scissors (rounded tips), dissect up.
  • Bone grafting: mineralized bone, cancellous bone, particle size 250-500mM preferred.
  • Membrane (Dura mater, freeze dried) resorbs slowly 7-8 months so it does not collapse into the grafted site. “Bioguide” from Zimmer great for perio, “Biomet extend” lasts longer. No need to stabilize the membrane.
  • Ideally, no pressure on the grafted site for 10-14 days. Then okay to wear an Essix retainer.
  • Any membranes has to cover the entire ridge.
  • Dental implants have to be stable at the time of placement. Otherwise it should be taken out….it will not osteointegrate.
  • Splitting the ridge technique– Need at least 3mm width. Need to keep the periosteum on the bone for blood supply – hence a supraperiosteal dissect for primary closure. Works great in the maxilla only, unpredictable in the mandible.  If the segment completely becomes free, stabilize it with a 24G wire between the implants. Extend as high as 10mm. Or cover with collagen membrane (salvin for 32 wks resorption)
  • Block grafts in esthetic zones are beneficial. Tension free closure, perfectly adapt the block, rigid fix, barrier membrane. He likes to use ramus.
  • If no cancellous bone from the medullary space –> no osteoblast!
  • With a block graft in the esthetic zone, you get better soft tissue support
  • For a prepped tooth and implant, using papilla sparing incisions, leaving a 2mm soft tissue collar. Always include the papilla in the incision if possible.
  • He uses cortico-cancellous allogenic blocks. Not cortical or cancellous bone only. Need both. Cortical bone helps with fixation, long screws that penetrate the palate, 2mm screws
  • Cover the mesh with collagen membrane to prevent soft-tissue ingrowth.
  • Leave mesh in 4-6 months.
  • Soft tissue grafting – 3 simple techniques
    • Tissue roll over – on the maxilla just borrow from the palate and move buccal. Midline releasing incision for better access. Fill the gap between placed implants and healing abutments with membrane. Long healing abutments to have the soft tissue around it.
    • Palatal grafting – for growing attached gingiva in the mandible. Or alloderm. 1mm thickness tissue is minimum. For connective tissue graft – be ware of GP artery. Cover the palate with stent to prevent complications, stays in for 48 hours, then okay to take on and off, but need to wear for a total of 5-7 days.
    • Connective Tissue Graft

Dr. R. Marx

  • Tibia bone harvest
    • Possible as an in office procedure preferably under IV sedation but can be done with local anesthesia.
    • Lateral approach is best, Gerdy’s tubercle, no muscle or vein or anything is near it. It’s close to the surface (only about 5mm from skin to bone). Ilio-tibial tract.
    • Can harvest up to average of 30cc of bone, (for sinus lift only need 7cc for only!
    • Put a pillow below the knee, to flex it in a passive fashion.
    • If right handed, go after the left knee, better angle of entry. And vice versa.
    • Do not use power tools to harvest the bone. Only use hand instruments. Otherwise you will go into the knee joint.
    • Full sterile prep and drape technique.
    • Local anesthesia: 1 carpule infiltrate subcutaneous and another carpule down to bone.
    • Incision is about 1 inch long
    • 1 cm window or opening into the cortex, then curette the bone out with spoon excavators (#4 Molt Curette)
    • Hemostatic agent: Avetin (powered bovine collagen), to prevent hematoma, at the osteotomy prior to layered closure.
    • Closure with ethicon sutures
    • Preop meds: Unasyn or doxycycline for IV meds. 12mg of decadron (good for surgical edema, supports bone growth) better than Medrol dose pak and solumedrol.
      Postop antibiotics: PCN VK or Augmentin or clindamycin
    • No running or sports for 6 wks. No need for crutches. Ice for 48hrs is enough. Elevate the leg
    • There is going to be a scar. Leg will swell below the knee and bruise.
    • Potential complications: fractures, knee joint issues, hematomas, wound dehiscence, scar, ecchymosis
  • Osteogenic bone grafting
    • Can use Allogenic corticocancellous bone, thin the cortex, soak in PRP, PRGF or even blood.
    • Round off any corner on the bone blocks
    • Lag technique for screw placement
    • PRP: accelerates normal soft-tissue and bone healing: VEGF, TGFb, EGF, PRGF…
    • 1cc of PRP has 250000-400000 of stem cells!
    • Natural blood clot has fibrin and other factors that help to heal the extraction sites.
    • Need at least 1 million / microliter of platelets after the PRP is concentrated, less is of no benefit.
    • After chronic periodontitis and loss of all the teeth, the periosteum has very little progenitor cells! Hence need to have osteoinduction.
    • BMP is now cleared for sinus lift and socket grafting
    • Product corruption is different than off label use of FDA approved drugs.
    • KLS resorbable mesh, instead of Titanium mesh. It lasts 3 months before its resorbed.
    • The BMP sponge from Medtronic’s is just a carrier and not a scaffold.
    • BMP will have lots of swelling, can use intraop decadron to reduce swelling.
    • To replace one tooth = you need 0.5mg of BMP
    • To fix continuity defect = you need 1mg/cm
    • The smallest BMP kit is 1.05mg.
    • Titanium Mesh exposure within 2 wks will lead to loss of some of the bone graft material and or infection. If over 2 wks, no issues, just keep on Peridex.
    • Come back in 6 month for implant placement.
    • The cleft lip and palate patients require a bit more BMP: 1mg /replaced tooth.
    • You can make a vestibular incision, instead of a crestal to prevent tissue dehiscence or mesh exposure.
    • If radiation post cancer – should not use BMP