Socket preservation

Socket preservation or alveolar ridge preservation is a procedure to reduce bone loss after tooth extraction, and either preserve the width of the dental alveolus (tooth socket) or expand it to allow for dental implant placement. After extraction, the jaw bone has a naturally tendency to become narrow, and lose it's original shape. Without socket preservation, the bone can quickly resorb, resulting in 30–60% loss in bone volume in the first six months after dental extraction. With socket preservation, the gum is retracted, the tooth is removed, material (usually a bone substitute) is placed in the tooth socket, it is covered with a barrier membrane, and sutured closed. Roughly 30 days after socket preservation, the barrier membrane is either removed, or it resorbs, and the callous of bone covers with new gingiva

Medical Uses

After tooth extraction, the alveolar ridge has a mean loos of width of 3.8mm, and a height loss of 1.24mm within six months. This loss of bone volume, can cause a denture to be loose, or an inadequate amount of bone width to place an implant. Historically, alveolar preservation was used to provide a base to retain conventional dentures. Advances in osseointegration have expanded the need of the procedure to maintain ridge width and height for dental implant placement. In some cases, where a tooth requires removal when other teeth still need to erupt, socket preservation may be used to maintain bone for the formative tooth to erupt into.

Risks and complications

While there are no absolute contraindicatons to socket preservation, many of the same cautions that apply to surgery on the jaws still apply to this procedure. Significant caution is required in an area previously exposed to radiation treatment, or in an area that has previously had osteomyelitis. Other considerations to bone healing include the concurrent use of bisphosphonate, and denosumab, smoking, diabetes, immunocompromise, and infection.

Another consideration is the risk of bone and soft tissue loss on the subsequent implant, long term. Socket preservation has been associated with a greater risk of marginal bone loss

Technique

Socket preservation is completed at the time of extraction. After removal of the tooth, the gum is elevated away from the bone, the socket is thoroughly cleansed, and antibiotic powder may be used. A barrier membrane is then fastened to the gum, the socket is packed with bone grafting material and the wound closed. Where the barrier membrane does not dissolve, it is removed approximately 30 days after placement.

Socket preservation of lower right 1st molar

Material types

• Autograft – Bone harvested from patient’s own body.
• Xenograft – Bone grafts or collagen from bovine or porcine origin.
• Allograft – Block bone graft from cadaver.
• Alloplast – Synthetic biomaterials such as fibrin scaffolds, PLGA, synthetic biodegradable polymer, hydroxyapatite, tricalcium phosphate, bioglass – ceramics etc.

Benefits

Socket preservation procedure prevents immediate bone resorption after extraction thus keeping the contour and integrity of the socket with successful and natural looking appearance for tooth restorative procedures. All dental prosthesis requires good jaw bone support for it to be successful in the long run. Without socket preservation, residual bones could lose volume resulting in loss of facial vertical and horizontal dimension and changes in facial soft tissues aesthetics.

A 2015 Cochrane study found that there was evidence that socket preservation does indeed improve the height and width, compared to extraction without socket preservation but that there is insufficient data to conclude that it decreases implant failures, improves esthetics, or that one grafting material is any better than another.

See also

• Guided bone and tissue regeneration
• Tooth regeneration

External links

• Bone augmentation and ridge preservation