Alveolar Ridge Maintenance

Robert Wiggs United States

Alveolar ridge maintenance (ARM) deals with the placement of osteopromotive materials at extraction sites in an attempt to maintain the physiologic and anatomic integrity of the alveolar bone. In the cases reviewed, we will demonstrate clinical differences in areas treated by techniques in comparison to those that have not. The reviewed cases show a definitive trend of greater long-term alveolar ridge maintenance when appropriate materials are placed in the alveolus following tooth extraction.

BIOLOGICAL BASIS

For successful clinical results, an understanding of the basic biological rationale is of great importance. Studies in the dog, in 1960, established that when various barriers were used to create selective compartments to excluded particular tissues that healthy new bone could be easily grown and guided into these compartments. It was proposed, in 1976, that the type of tissue healing following periodontal therapy was highly dependent upon the type of tissue that first repopulates a tooth�s root surface. This theory proposed that four different types of periodontal tissues had the potential to repopulate the root surface following surgical therapy. These are gingival epithelium, gingival connective tissue, alveolar bone, and the periodontal ligament. In addition, other research suggested that each type of cell type resulted in a different potential outcome. Gingival epithelium repopulating the root surface resulted in a long epithelial attachment that was easily re-invaded and destroyed by infection and inflammation. When gingival connective tissue was first to repopulate the root surface, root resorption was common to occur. When bone was first, ankylosis and resorption resulted. However, if cells of the periodontal ligament were first, a new healthy attachment occurred. Additional studies and investigations in the 1990s have supported this basic hypothesis. These new developments in the modality of treatments of periodontal disease have indicated that some teeth that would have been previously extracted can now be salvaged and therefore weakening of the jaws from extractions, can be prevented or treated.

A series of cases are presented, demonstrating the difference in bone maintenance in treated and non-treated extraction sites. These clinical results indicate a probable benefit to placement of osseoconductive materials in extraction sites for the purpose of maintaining alveolar bone height. It is surmised that maintenance of bone height translates to a jaw more resistant to atrophy and fracture.

SUGGESTED READING

1.  Christensen GJ: Ridge Preservation: Why Not? JADA 127:669, May 1996

2.  Desjardins RP: Hydroxyapatite for alveolar ridge augmentation: indications and problems. J Prosthet Dent 54:374, 1985.

3.  Wiggs RB, Lobprise HB, Mitchell P. Oral and Periodontal Tissue Maintenance, Augmentation, Rejuvenation, and Regeneration, In: Veterinary Clinics of North America. 1998;28(5):1165.

4.  Wiggs RB, Lobprise HB: Periodontology. In Veterinary Dentistry, Principles and Practice. Philadelphia, Lippincott-Raven Pub, 1997.

5.  Wilson J, Yu LT, Beale BS: Bone augmentation using Bioglass particles in dogs: pilot study, Bioceramics 5:139, 1992.