3i Clinical Case Report:
GRAFTING OF THE POSTERIOR MAXILLA FOR PREPARTION OF IMPLANT PLACEMENT
By Alan M. Meltzer DMD, MScD
About the Author:
Alan M. Meltzer DMD, MScD is a graduate of the school of Dentistry at the University of Pennsylvania in Philadelphia. He received his certificate of Periodontics at Boston University. Dr. Meltzer has published numerous articles in the field of dental implantology and bone grafting.
Initial Patient Presentation
A female patient in her middle sixties, was referred for replacement of a failing 5-unit fixed partial denture in the left posterior maxilla. The distal abutment (#15) had +2 mobility and was considered unsuitable as a terminal abutment for a fixed prosthesis.
Partially edentulous maxilla
Failing 5 unit FPD (#11 to #15)
Pneumatized maxillary sinus with inadequate bone volume for implant placement #14
Adequate bone volume for implant placement #12 and #13
Placement of a provisional fixed bridge #11 to #15
Placement of a sinus graft to permit future placement of an implant into site #14
Placement of three OSSEOTITE implants to replace #s 12, 13, & 14
Abutment connection/implant-retained fixed bridge for #s 12-14
STEP 1. SINUS MEMBRANE ELEVATION
The sinus membrane was successfully elevated using a lateral window approach. The bony walls were scored internally to produce blood supply of bony origin.
Success with alloplastic grafts depends on the graft being contained within a clot and an adequate blood supply emanating from the host bone.
STEP 2. PLACEMENT OF GRAFT MATERIAL
After the membrane is elevated, the recipient site is filled with BIOGRAN, resorbable synthetic bone graft material. The material is packed firmly starting mesio-palatally and progressing toward the surgically created window.
The BIOGRAN must be well condensed against the bony walls of the graft site to minimize iatrogenically induced voids.
STEP 3. MEMBRANE PLACEMENT
The graft window is covered with Gore-Tex OV-4 e-PTFE regenerative membrane. The borders of the membrane must extend 2-3 mm beyond the window to fulfill the GBR protocol requirements
Screw/tacks were not used because once the membrane was placed against the graft, it laid passively over the window and against the surrounding bone.
The flap was closed with a combination of Gore-Tex interrupted and mattress sutures. Tension-free primary closure was achieved.
STEP 4. HEALING
The area was allowed to heal for nine months. CT scans were taken to assess the quantity and density of bone in the grafted site prior to implant placement
STEP 5. IMPLANT PLACEMENT
Three OSSEOTITE implants were placed using the standard two-stage protocol:
3.75 mm diameter implants for #s 12 and 13
5 mm diameter implant for # 14
All healing was uneventful, the soft and hard tissue response to the BIOGRAN was excellent. It was evident that the BIOGRAN grafted site resulted in outstanding osseous regeneration and provided a clinically acceptable bed for the placement of an osseointegrated implant-supported fixed prosthesis.
Conical abutments were placed after the soft tissues had healed following Stage II surgery. A screw-retained restoration was placed as a definitive restorative treatment. Tooth # 15 was extracted after the restorations were placed.
Nine months after the placement of the sinus graft, tissue was gathered using a trephine but from site #14 for Histologic evaluation. It is evident that new bone is present in the graft site.
A 20X power examination reveals new bone produced in direct contact to BIOGRAN. No fibrous encapsulation was noted around any part of the alloplastic graft. Histology supports the fact that BIOGRAN is an outstanding osseoconductive material and it has been noted that in some cases the first evidence of bone formation is actually within the BIOGRAN granule thereby suggesting the material may be osseostimulatory.