Bone grafting after tooth removal: Why, when, and what to use

Why?

Tooth extraction is a common practice in the United States, with a prevalence of roughly 50% of adults in the age range 20–64 having at least one tooth extracted. (1) The normal pattern of bone healing post-tooth extraction is resorptive, typically leaving both hard- and soft-tissue defects in the alveolus without site preservation and/or tissue grafting. (2) This is problematic as loss of tissue structure in the jaw directly affects the functional and esthetic outcomes of dental implants, as well as tooth-borne fixed prosthetics (dental bridges).

Although unpredictable, a greater amount of alveolar ridge loss following extraction usually occurs in the horizontal dimension and affects the buccal bone of the ridge. (3) In fact, 50% of alveolar bone dimension can be lost after tooth extraction, with losses reported of up to 6–7 mm (figure 1). Two-thirds of this loss of bone volume can occur within the first three months of tooth extraction. (4)

Figure 1: Site No. 29 was extracted one year prior to the photo, resulting in severe ridge resorption and the need for ridge augmentation prior to dental implant treatment. — **Figure 1:** Site No. 29 was extracted one year prior to the photo, resulting in severe ridge resorption and the need for ridge augmentation prior to dental implant treatment.

Loss of vertical ridge height can also occur and usually takes place along the buccal aspect of the ridge to a lesser degree than horizontal ridge loss. (5) Corresponding reductions in vertical ridge height ranging from 2–4 mm have been noted. (6) The combination of this resorptive pattern results in a ridge that has moved in a palatal/lingual direction and has atrophied vertically (figure 1a).

Figure 1a: Loss of both hard and soft tissue in a horizontal and vertical dimension — **Figure 1a:** Loss of both hard and soft tissue in a horizontal and vertical dimension

These alveolar bone changes often compromise implant placement due to thin bone volume (figures 2a–2d).

Figure 2a: Abscess at the apex of implant No. 10 placed two years ago. The tooth was removed, and the site was not preserved with graft material. The implant was placed six months after tooth removal. — **Figure 2a:** Abscess at the apex of implant No. 10 placed two years ago. The tooth was removed, and the site was not preserved with graft material. The implant was placed six months after tooth removal.

Figure 2b: Flap surgery of the implant showing fenestration of the implant through the buccal wall due to deficient bone volume — **Figure 2b:** Flap surgery of the implant showing fenestration of the implant through the buccal wall due to deficient bone volume

Figure 2c: Buccal bone of implant was augmented with Geistlich Bio-Oss Collagen to save the implant from explantation — **Figure 2c:** Buccal bone of implant was augmented with Geistlich Bio-Oss Collagen to save the implant from explantation

Figure 2d: Final implant after it was stabilized with ridge augmentation — **Figure 2d:** Final implant after it was stabilized with ridge augmentation

Reduction in quantity and quality of bone can also compromise functional and esthetic outcomes of both implants and fixed bridge restorations (figures 3 and 3a).

Figure 3: Prosthetic (pink) porcelain needed on an implant bridge to mask hard- and soft-tissue loss — **Figure 3:** Prosthetic (pink) porcelain needed on an implant bridge to mask hard- and soft-tissue loss

Figure 3a: Soft- and hard-tissue loss on a tooth-borne bridge after extraction without grafting, resulting in an unesthetic restoration — **Figure 3a:** Soft- and hard-tissue loss on a tooth-borne bridge after extraction without grafting, resulting in an unesthetic restoration

When?

Because of this alveolar resorptive pattern after tooth extraction, bone grafting the extraction socket post-tooth extraction procedures has become a solution that attempts to limit the amount of hard- and soft-tissue loss. There are many systematic reviews in the literature that compare the results of residual ridge dimension following tooth extraction after the use of a bone graft (with or without a membrane) versus extraction alone without grafting. (7) Sockets that were preserved with bone grafting and/or membrane on average lost 2 mm less of ridge width, 1 mm less of ridge height, and had 20% more bone volume when compared to sockets that were not grafted. (8) Maxillary sites lost more than mandibular sites, and most ridge resorption occurred on the buccal aspect of the ridge.

Indications for bone grafting extraction sites include the following:

• Site development to increase hard and soft tissue for pontic sites in fixed bridge prosthetics (figures 4–4e)

Figure 4: Severe bone and soft-tissue loss after extraction without grafting would force the pontic of this bridge to be long and unesthetic. — **Figure 4:** Severe bone and soft-tissue loss after extraction without grafting would force the pontic of this bridge to be long and unesthetic.

Figure 4a: Collapse of hard and soft tissue under fixed bridge after tooth extraction without grafting. — **Figure 4a:** Collapse of hard and soft tissue under fixed bridge after tooth extraction without grafting.

Figure 4b: Severe defect with horizontal and vertical bone loss — **Figure 4b:** Severe defect with horizontal and vertical bone loss

Figure 4c: Pontic site development with Geistlich Bio-Oss Collagen and Geistlich Bio-Gide — **Figure 4c:** Pontic site development with Geistlich Bio-Oss Collagen and Geistlich Bio-Gide

Figure 4d: Final bridge insertion after pontic site development. — **Figure 4d:** Final bridge insertion after pontic site development.

Figure 4e: Final picture of smile — **Figure 4e:** Final picture of smile

• Rebuild defects around adjacent teeth after extracting teeth due to periodontal disease (figures 5a–5c)

Figure 5a: Radiograph of severe bone defect after tooth extraction with bone loss affecting adjacent teeth — **Figure 5a:** Radiograph of severe bone defect after tooth extraction with bone loss affecting adjacent teeth

Figure 5b: Site augmentation with Geistlich Bio-Oss Collagen and collagen membrane — **Figure 5b:** Site augmentation with Geistlich Bio-Oss Collagen and collagen membrane

Figure 5c: 12 months postoperative radiograph of healing — **Figure 5c:** 12 months postoperative radiograph of healing

• Correct bone defects impinging upon anatomical structures after tooth extraction, such as oroantral communication (figure 6)

Figure 6: Image of tooth with large infection that will require bone graft after extraction to keep sinus intact and from pneumatizing — **Figure 6:** Image of tooth with large infection that will require bone graft after extraction to keep sinus intact and from pneumatizing

• Preserve tissue structure for subsequent dental implant therapy

Decision matrix

With that in mind, does every extraction socket need to be grafted? The answer is no. A good decision matrix one can use is based on “A Simplified Socket Classification and Repair Technique” by Elian et al. (9)

Classification when existing tooth is still present:

• Type 1 socket—Buccal plate present and soft tissue present

Type 1a (figure 7)—Thick biotype, posterior tooth, and buccal plate present: no graft needed

Figure 7: Type 1a socket — **Figure 7:** Type 1a socket

Type 1b (figure 8)—Thick biotype, anterior tooth, and buccal plate present: clot stabilizer

Figure 8: Type 1b socket — **Figure 8:** Type 1b socket

Type 1c (figure 9)—Thin biotype, anterior or posterior, and buccal plate present: bone graft

Figure 9: Type 1c socket — **Figure 9:** Type 1c socket

• Type 2 socket (figures 10a and 10b)—Buccal plate missing, but soft tissue present: bone graft +/- membrane (if graft containment is needed)

Figure 10a: Type 2 socket — **Figure 10a:** Type 2 socket

Figure 10b: Type 2 socket after tooth extraction, showing loss of buccal plate — **Figure 10b:** Type 2 socket after tooth extraction, showing loss of buccal plate

• Type 3 socket (figure 11)—Buccal plate missing and soft tissue missing: bone graft + membrane +/- biologic agent (consider soft-tissue graft if keratinized tissue is less than 2 mm)

Figure 11: Type 3 socket with buccal plate and soft-tissue loss — **Figure 11:** Type 3 socket with buccal plate and soft-tissue loss

What?

Although there are many types of grafting products commercially available, choosing the right one may be difficult. An ideal bone graft substitute should be biomechanically stable; able to degrade within an appropriate time frame; exhibit osteoconductive, osteogenic, and osteoinductive properties; as well as provide a favorable environment for invading blood vessels and bone-forming cells. (10) The graft material used should facilitate the three tenants of bone regeneration: clot stability, space maintenance, and blood supply/bone-forming cells. (11) [Read more about bone grafts in “A review of bone graft material,” by Adam Bear, DDS.]

Unfortunately, many clinicians assume all grafting products are created equal and select the material based on price point alone. If the bone grafting material is not formulated correctly, degradation may not occur, and the graft can become fibrously encapsulated, leading to poor bone turnover and graft failure (figures 12a–12c).

Figure 12a: Radiograph of site No. 30 12 months after bone graft — **Figure 12a:** Radiograph of site No. 30 12 months after bone graft

Figure 12b: CT scan of bone graft showing poor graft healing and fibrous encapsulation — **Figure 12b:** CT scan of bone graft showing poor graft healing and fibrous encapsulation

Figure 12c: Surgery of graft with poor healing and need to be removed and regrafted — **Figure 12c:** Surgery of graft with poor healing and need to be removed and regrafted

One particularly good bone graft material that provides scaffolding space maintenance as well as stabilizes the blood clot is Geistlich Bio-Oss Collagen (Geistlich Pharmaceuticals). (12) Geistlich Bio-Oss Collagen is 90% Bio-Oss granules (size range 0.25–1.0 mm) and 10% collagen. The proprietary formulation of the collagen component gives the material its scaffolding and moldability qualities, which makes it an excellent product for site preservation after tooth extraction, especially during flapless site preservation. (13) Finally, this graft material has been shown to outperform other graft materials in comparative studies looking at site preservation after tooth extraction. (14)

Related video: Extraction and socket grafting in preparation for dental implant placement

This surgical video demonstrates removal of a tooth with loss of buccal plate and grafting of the remaining socket with Geistlich Bio-Oss Collagen and Geistlich Bio-Gide to preserve the ridge for implant placement.

Editor's note: Join us for the not-to-miss Perio-Implant Advisory Symposium on October 23, 2020. In this important virtual meeting, you’ll learn the newest skills it takes to save patients’ natural dentition. Bring your team and transform your practice. Conference schedule and special rates available at this link. Presented by Geistlich Biomaterials.

References

1. Dye BA, Thornton-Evans G, Li X, Iafolla TJ. Dental caries and tooth loss in adults in the United States, 2011–2012. NCHS data brief, No. 197. Hyattsville, MD: National Center for Health Statistics; 2015. https://www.cdc.gov/nchs/data/databriefs/db197.pdf.

2. Agarwal G, Thomas R, Mehta D. Postextraction maintenance of the alveolar ridge: rationale and review. Compend Cont Educ Dent. 2012;33(5):320-324; quiz 327, 336.

3. Hansson S, Halldin S. Alveolar ridge resorption after tooth extraction: A consequence of a fundamental principle of bone physiology. J Dent Biomech. 2012;3:1758736012456543. doi:10.1177/1758736012456543.

4. Schropp L, Wenzel A, Kostopoulos L, Karring T. Bone healing and soft tissue contour changes following single-tooth extraction: a clinical and radiographic 12-month prospective study. Int J Periodontics Restorative Dent. 2003;23(4):313-323.

5. Lekovic V, Camargo PM, Klokkevold PR, et al. Preservation of alveolar bone in extraction sockets using bioabsorbable membranes. J Periodontol. 1998;69(9):1044-1049. doi: 10.1902/jop.1998.69.9.1044.

6. Lam RV. Contour changes of the alveolar processes following extraction. J Prosthet Dent. 1960;10:25-32.

7. Avila-Ortiz G, Elangovan S, Kramer KW, Blanchette D, Dawson DV. Effect of alveolar ridge preservation after tooth extraction: a systematic review and meta-analysis. J Dent Res. 2014;93(10):950-958. doi:10.1177/0022034514541127.

8. Aimetti M, Manavella V, Corano L, Ercoli E, Bignardi C, Romano F. Three‐dimensional analysis of bone remodeling following ridge augmentation of compromised extraction sockets in periodontitis patients: a randomized controlled study. Clin Oral Implants Res. 2018;29(2):202-214. doi:10.1111/clr.13099. Epub November 17, 2017.

9. Elian N, Cho SC, Froum S, Smith RB, Tarnow DP. A simplified socket classification and repair technique. Pract Proced Aesthet Dent. 2007;(19)2:99-104; quiz 106.

10. Janicki P, Schmidmaier G. What should be the characteristics of the ideal bone graft substitute? Combining scaffolds with growth factors and/or stem cells. Injury. 2011;42(suppl 2):S77-S81.

11. Mellonig JT, Triplett RG. Guided tissue regeneration and endosseous dental implants. Int J Periodontics Restorative Dent. 1993;13(2):108-119.

12. Araújo Mauricio, Linder E, Wennström J, Lindhe J. The influence of Bio-Oss Collagen on healing of an extraction socket: an experimental study in the dog. Int J Periodontics Restorative Dent. 2008;28(2):123-135.

13. Cardaropoli D, Tamagnone L, Roffredo A, De Maria A, Gaveglio L. Alveolar ridge preservation using tridimensional collagen matrix and deproteinized bovine bone mineral in the esthetic area: a CBCT and histologic human pilot study. Int J Periodontics Restorative Dent. 2018;38(suppl):S29-S35. doi:10.11607/prd.3702.

14. Scheyer ET, Heard R, Janakievski J, et al. A randomized, controlled, multicentre clinical trial of post‐extraction alveolar ridge preservation. J Clin Periodontol. 2016;43(12):1188-1199. doi:10.1111/jcpe.12623.

Editor’s note:This article originally appeared in Perio-Implant Advisory, a chairside resource for dentists and dental hygienists for issues relating to periodontal and implant medicine. Exclusive content from an academic perspective centers on complex care, solving clinical complications from a team-based approach through interdisciplinary management.

MORE CLINICAL TIPS FROM DR. SCOTT FROUM . . .

Scott Froum, DDS, a graduate of the State University of New York, Stony Brook School of Dental Medicine, is a periodontist in private practice at 1110 2nd Avenue, Suite 305, New York City, New York. He is the editorial director of Perio-Implant Advisory and serves on the editorial advisory board of Dental Economics. Dr. Froum, a diplomate of the American Board of Periodontology, is a clinical associate professor at SUNY Stony Brook School of Dental Medicine in the Department of Periodontology. He serves on the board of editorial consultants for the Academy of Osseointegration's Academy News. Contact him through his website at drscottfroum.comor (212) 751-8530.