Avoiding dental implants and the sinus lift procedure: Revisiting maxillary molar root amputation

The replacement of hopeless or missing teeth can be predictably achieved with dental implants and have historically high survival rates.¹ Implants placed in the mandible have demonstrated higher survival rates than implants placed in the maxilla,² but if performed correctly maxillary implants still enjoy high survival rates in the literature.^3,4

Implant failures do occur, however, and implants placed in the posterior maxilla typically have the highest chance of failure.⁵ Reasons for increased implant

Figure 1: CBCT showing root perforation after endodontic therapy on the mesial buccal root of no. 3

failure in the posterior maxilla include inferior bone quality, limited bone quantity, and sinus proximity.⁶ In addition, some studies suggest that implants placed in the posterior maxilla are more likely to be affected by patient-related factors such as diabetes and smoking status.⁷ An alternative to tooth extraction, sinus augmentation (especially when replacing teeth that have lost bone to periodontal disease), and implant therapy can be the tooth-saving procedure known as maxillary root amputation.

Root amputation: How and why?

Figure 2: Periapical of tooth no. 3 prior to root amputation surgery

Maxillary root amputation is the process by which one of the roots of a maxillary tooth (usually distal buccal root and, to a lesser degree, mesial buccal root) are removed at the level of the furcation, while leaving the crown and remaining roots in function.⁸ Root amputation is used to save teeth suffering from furcation involvement, failed endodontic treatment, horizontal root fractures, and vertical root fractures that would otherwise need to be extracted (figures 1 and 2).⁹

Case selection and clinical considerations

Saving compromised multirooted teeth with root amputation can often be successful, but the technique is sensitive and complex. Proper case selection is essential, and considerations include the following:

There is sufficient bone support around the remaining roots (at least 50% or more is needed) along with sufficient coronal tooth structure (figure 3).

Figure 3: Clinical entry showing more than 50% of bone on the distal and palatal of no. 3

Proper periodontal surgical removal of amputated root, including beveling of furcated area to improve soft-tissue adherence and plasty/polishing of the remaining root to prevent a nidus for plaque accumulation (figures 4–6).

Proper endodontic therapy of remaining roots before or after root amputation is a requirement.

Full-coverage restoration with proper occlusal considerations and limited lateral interferences will increase success rates.

Proper hygiene follow-up and attention to periodontal recare visits will

Figure 4: Root amputation and removal of MB root with bevel and polishing of furcation

increase the long-term success rate of treated teeth (figures 7 and 8).

How does root amputation compare with other surgical procedures?

The prognosis is good for molar teeth treated with root amputation, provided case selection and treatment are performed properly. Fugazzottoreported 15-year cumulative success rates comparing molar root resection to molar implant placement, with survival rates of 96.8% for root-resected molars and 97.0% for molar implants.¹⁰ This study was done in private practice with proper oversight and case selection.

Figure 5: Graft of defect with Bio-Oss Collagen for structural support

The study concluded that molar root resection therapy and implant therapy have a comparable degree of functional success.

Figure 6: Addition of Bio-PRF to promote angiogenesis and upregulate the healing cascade

Another study looked at the retention rate of root-resected molars at 10 years and reported an overall success rate of 70.2%. Teeth with more than 50% bone around the remaining roots had a much higher degree of long-term survival. Teeth treated with root resection due to periodontal problems showed a higher

Figure 7: Clinical photo one year healing after surgery

long-term survival rate than teeth that had resection due to caries, root fracture, and endodontic failure. This finding is important relative to a recent paper suggesting that patients with treated chronic periodontal disease had a 10 times higher failure rate with dental implants than if their own natural dentition was saved with periodontal therapy.

Figure 8: Periapical of bone fill in mesial buccal root one year after graft

Conclusion

Root amputation remains a viable treatment to save maxillary molars and can have long-term success rates equal to dental implant therapy (figures 9 and 10).

Figure 9: Molar with grade II furcation and suspected mesial buccal fracture

Patients who are not eligible for dental implant therapy due to medical history, social history, financial limitations, and/or who do not want an implant or sinus augmentation treatment may be candidates for this type of procedure. Proper interdisciplinary treatment planning, case selection, and technique will determine the success of long-term outcomes.

Figure 10: Same molar tooth six years showing excellent stability after root amputation

Editor’s note: This article originally appeared in Perio-Implant Advisory, a chairside resource for dentists and hygienists that focuses on periodontal- and implant-related issues. Read more articles and subscribe to the newsletter.

References

Brånemark PI, Hansson BO, Adell R, et al. Osseointegrated implants in the treatment of the edentulous jaw. Experience from a 10-year period. Scand J Plast Reconstr Surg Suppl. 1977;16:1-132.
Fouda AAH. The impact of the alveolar bone sites on early implant failure: a systematic review with meta-analysis. J Korean Assoc Oral Maxillofac Surg. 2020;46(3):162-173. doi:10.5125/jkaoms.2020.46.3.162
den Hartog L, Slater JJRH, Vissink A, Meijer HJA, Raghoebar GM. Treatment outcome of immediate, early and conventional single-tooth implants in the aesthetic zone: a systematic review to survival, bone level, soft-tissue, aesthetics and patient satisfaction. Clin Periodontol. 2008;35(12):1073-1086. doi:10.1111/j.1600-051X.2008.01330.x
Adell R, Lekholm U, Rockler B, Brånemark PI. A 15-year study of osseointegrated implants in the treatment of the edentulous jaw. Int J Oral Surg. 1981;10(6):387-416. doi:10.1016/s0300-9785(81)80077-4
Pabst AM, Walter C, Ehbauer S, et al. Analysis of implant-failure predictors in the posterior maxilla: a retrospective study of 1395 implants. J Craniomaxillofac Surg. 2015;43(3):414-420. doi:10.1016/j.jcms.2015.01.004
Huynh-Ba G, Friedberg JR, Vogiatzi D, Ioannidou E. Implant failure predictors in the posterior maxilla: a retrospective study of 273 consecutive implants. J Periodontol. 2008;79(12):2256-2261. doi:10.1902/jop.2008.070602
Kasat V, Ladda R. Smoking and dental implants. J Int Soc Prev Community Dent. 2012;2(2):38-41. doi:10.4103/2231-0762.109358
Walter C, Weiger R, Zitzmann NU. Periodontal surgery in furcation-involved maxillary molars revisited—an introduction of guidelines for comprehensive treatment. Clin Oral Investig. 2011;15(1):9-20. doi:10.1007/s00784-010-0431-9
Park SY, Shin SY, Yang SM, Kye SB. Factors influencing the outcome of root-resection therapy in molars: a 10-year retrospective study. J Periodontol. 2009;80(1):32-40. doi:10.1902/jop.2009.080316
Fugazzotto PA. A comparison of the success of root resected molars and molar position implants in function in a private practice: results of up to 15-plus years. J Periodontol. 2001;72(8):1113-1123. doi:10.1902/jop.2001.72.8.1113

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 volunteer professor in the postgraduate periodontal program at SUNY Stony Brook School of Dental Medicine. Contact him through his website at drscottfroum.com or (212) 751-8530.