Socket Augmentation: Rationale and Technique (Part 2)

Layers Technique (when buccal plate is ≤1 mm thickness)

The layers technique was developed to maximize bone healing in sockets with compromised healing potential.
A combination of a bone replacementgraft and a collagen wound dressing material should be used when the buccal socket wall is ≤1 mm thick at approximately 2–3mm below the alveolar crest and/or occurrence of dehiscence or fenestrations are found. Mineralized bone grafts that are quickly replaced by host bone are
preferable.
The bone graft should be tamped down lightly, and overfill should be avoided. Adequate space between the graft particles is critical to allow for revascularization to spread throughout the graft, bringing the proteins and growth factors necessary for new bone growth (Becker et al. 1992, Mellonig 1996).

The histologic data obtained from our unpublished data indicated 68% of vital bone, 5% of residual particle, and 27% of connective tissue. This is similar to the human host bone component. Sites that may also benefit from using this technique include those with thin bone ≤1 mm, periapical pathologies, and sockets of multirooted teeth associated with loss of the interradicular bone.

The histologic data obtained from our unpublished data indicated 68% of vital bone, 5% of residual particle, and 27% of connective tissue. This is similar to the human host bone component. Sites that may also benefit from using this technique include those with thin bone ≤1 mm, periapical pathologies, and sockets of multirooted teeth associated with loss of the interradicular bone.

Abd El Salam El Askary, Fundamentals of Esthetic Implant Dentistry, 2007

Future posts will describe cases,  in which the buccal plate is absent or was lost during exodontia require a different approach

Socket Augmentation: Rationale and Technique

Tooth extraction, either traumatic or atraumatic, results in alveolar bone loss, both in width and height (Bays
1986, Mecall and Rosenfeld 1996, Mecall and Rosenfeld 1992, Mecall and Rosenfeld 1991). An average of 40% to 60% of original height and width is expected to be lost after tooth extraction, with the greatest loss happening within the first year (Sevor and Meffert 1992, Polizzi et al. 2000, Grunder et al. 1999, Werbitt and Goldberg 1992, Werbitt and Goldberg 1991). This can negatively influence bone volume that is needed for future dental implant placement as well as proper ideal esthetic restoration. Research has demonstrated that the alveolar ridge at the maxillary anterior area can be reduced by 23% in the first six months after tooth extraction, and an additional 11% in the following five years (Artzi et al. 2000). In the posterior mandible, resorption happens primarily in the buccal/labial direction, resulting in a lingual displacement of alveolar crest (Artzi et al. 2000).

Traditional Socket Management with or without Collagen Wound Dressing Material (socket management when
buccal plate is ≥1 mm thickness):

Abd El Salam El Askary, Fundamentals of Esthetic Implant Dentistry, 2007

Future posts will describe cases, when buccal plate is ≤1 mm thickness and Cases in which the buccal plate is absent or was lost during exodontia require a different approach

Socket Preservation technique before implant placement

Human mineralized bone in extraction sites before implant placement

After tooth extraction, labial or facial bone loss may be significant, resulting in less-thanideal
bone being available for implant placement. Horizontal or vertical deficiency with
loss of interseptal, mesial or distal bone also may occur, depending on the etiology
leading to tooth extraction, such as severe periodontal disease or chronic
bone loss from tooth fracture. Even after a “clean” extraction, bone loss may be
unpredictable, resulting in limitation of ideal implant placement.

Major changes of an extraction site take place during the 12 months following tooth extraction. The width of the alveolar ridge was reduced by 50% during the observation period (12 months). This loss, corresponding to 5 to 7 mm, is in agreement with earlier studies. The finding that approximately two thirds of this reduction occurred within the first 3 months after tooth extraction also corresponds to earlier findings.(Lars Schropp, 2003)

In an effort to preserve and create sufficient bone for implant placement after mandibular molar extraction, we have used human mineralized cancellous bone (Puros, Sulzer Dental, Carlsbad, Calif.) as a graft material. For mandibular molar sites, we have used advancement flaps to achieve primary closure, without the use of membranes or collagen. This technique has allowed
for successful placement of implants in molar sites that otherwise may not have had satisfactory amounts of bone for ideal implant placement.

Background. Bone loss after tooth extraction may prevent dental implant placement. Human mineralized bone grafts can be used to restore bone volume and allow for tooth replacement with dental implants.
Methods. The authors grafted 22 sites in 18 patients with human mineralized bone after tooth extraction. They allowed molar sites 16 weeks for graft healing, placed the implants
and restored them with a final crown after a four-month integration period. Singlerooted
maxillary sites received implants and immediate placement of provisional crowns or underwent a delayed two-stage restoration approach. The authors used radiographs and clinical examinations to evaluate the results.
Results. All of the sites were restored successfully with a single-tooth implant restoration.
Periapical radiographs indicated that the crestal bone levels were limited to
the first thread of the implants or slightly coronal to the first thread of the implant.
Clinical evaluation indicated excellent gingival health around the provisional and
final restorations, without obvious gingival migration.
Conclusions. The use of human mineralized bone may have significant potential to
reconstruct missing bone resulting from tooth extraction and to preserve bone after
tooth extraction. In addition, healed bone graft sites seem to be able to support immediate
placement of a provisional crown and implant restorations.
Clinical Implications. Patients who are having teeth extracted may become candidates
for implant restorations when the sites are appropriately grafted to preserve and reconstruct bone volume, thus allowing for more options for reconstructing the
missing tooth site.

CASE PRESENTATION

MICHAEL S. BLOCK, D.M.D.; ISRAEL FINGER, D.D.S.,
ROBERT LYTLE, D.D.S.

J Am Dent Assoc 2002;133;1631-1638