Alveolar Ridge Atrophy

The ridge can resorb after teeth are lost. Age, traumatic damage, disease, osteoporosis, mineral-metabolism disorders and hormone imbalance are among the factors linked with the amount of resorption.

Ridge assessment records the bone structure that remains after teeth are lost. Standardised radiographs can detect changes in the upper and lower jaw early.

Full or partial dentures supported by mucosa, or by mucosa and gingiva, are associated with more extensive ridge resorption than partial dentures supported by gingiva and mucosa.

Standardised intraoral or panoramic radiographs can identify changes in jawbone structure. For an implant site, imaging also maps the nasal floor and maxillary sinus in the upper jaw and the mandibular canal in the lower jaw.

When the upper-jaw sinus limits implant placement, options described include short implants, sinus lifting and bone augmentation. Ridge preservation after extraction may reduce the loss of ridge volume before delayed implant placement.

Planning may include implant placement alone or may include sinus lifting or bone augmentation when the available anatomy requires those procedures.

The lower jaw's inferior alveolar canal contains a nerve and artery. Injury during implant placement can cause pain, altered sensation or excessive bleeding; upper-jaw implant surgery can also perforate the maxillary sinus.

After extraction, ridge-preservation methods aim to limit loss of ridge volume. They do not predictably prevent bone loss at every site, but may reduce the need for grafting before or during implant placement.