Why Should I Recommend Site Preservation To My Patients?
Normal marginal gingiva and intact interdental papillae are absolute prerequisites for achieving esthetic restorations and optimal emergence profiles following tooth removal in the anterior maxilla. Maintenance of adequate soft tissue anatomy is predicated upon maintaining an adequate volume of supporting alveolar bone. Frequently, however, crestal bone loss following tooth extraction disturbs the critical balance between underlying crestal bone and overlying soft tissues, resulting in gingival recession, distortion, and loss of interdental papillae.
Multiple studies have documented predictable 3-4 mm of buccolingual and apicocoronal ridge resorption within the first six months of tooth extraction in the anterior esthetic zone of the maxilla. Without further treatment, up to 50% buccolingual ridge width reduction will occur, dramatically reducing the potential for an optimal esthetic outcome.1,2,3 Various causes of post-extraction bone loss have been identified including advanced periodontal disease, periapical infection, developmental defects, disruption of periodontal ligament fibers, and loss of the critical blood supply.3,4 As a consequence of such bone loss, negative soft tissue changes will predictably occur resulting in a reduction or loss of keratinized marginal gingiva and disappearance of interdental papillae.
It is well understood that immediate grafting of extraction sockets (site preservation), especially in the esthetic zone of the maxilla, will compensate for post-extraction bone loss and its associated esthetic challenges. While site preservation techniques are often simple, several key factors must be considered by the clinician in order optimize the clinical outcome:
- The graft material selected should be highly osteoconductive, with an extensive network of interconnected pores that allow infiltration of an early blood supply to the grafted site.
- The graft material should provide a long-term 3-D scaffold in order to maintain the proper bony architecture of the extraction socket site.
- The graft material must help support the growth of sufficient quantities of vital, healthy new bone.
- Care should be taken to place the graft up to the level of the marginal bone crest.
A recent prospective study by Dr. Dong-Woon Lee et al compared the efficacy of three types of graft materials in regenerating vital bone and concluded that deproteinized bovine bone mineral (Bio-Oss®) provided the most desirable results.5 This study is particularly important for both clinicians and their patients as it provides evidence-based information upon which informed choices can be made when selecting appropriate graft materials for extraction socket preservation procedures.
_______________________________________________________________________
1Lekovic V. et al., J Periodontol 1998 Sep;69(9):1044-49
2Schropp L. et al., Int J Periodontics Restorative Dent 2003 Aug;23(4):313-323
3Nevins M, et al., Int J Periodontics Restorative Dent 2006;26:19-29
4Araujo M., et al., Int J Periodontics Restorative Dent 2008;28:123-135
5Lee, DW, et al., Int J Oral Maxillofac Implants 2009;24:609-615