Preserving Natural Dentition in Endodontically Treated Teeth
In some cases, an implant isn’t the go-to solution
Today dentists are placing more implants than ever before. Implant advertisements seem to be everywhere—dental magazines, conventions, and meetings—with companies showcasing the ease of use and long-term predictability of new systems. Implants have come a long way in their relatively short history, and in some cases, they may be the preferred treatment modality. However, implants aren’t always the answer.
A dentist’s primary goal is to maintain the patient’s optimal oral health, including the natural dentition. Although some general dentists may believe implants are better than endodontically preserving natural teeth, this idea is not scientifically supported by the literature. In fact, most studies show that an implant and a single-rooted endodontically treated tooth have similar success rates, but implants lead to a higher rate of postoperative complications.1,2
Table 13-11 provides several considerations for placing an implant verses saving the natural tooth, such as the location of the implant, the quality of available bone, and various systemic factors. For example, placing implants in the esthetic zone, especially in the anterior maxillary region, often presents a challenge (Figure 1).3 Systemic factors can contribute to peri-implantitis (Figure 2 and Figure 3) and reduce the survival rate for implants.9
In situations such as these, oral health care providers must consider what they would want if it was their tooth. This introspection may help the practitioner decide what is in the best interest of the patient and provide transparency. Because of the information proliferation on the Internet and social media, patients believe they are now better educated on dental options and services. If dentistry is to remain grounded in integrity, honesty, and trust, then dentists must provide patients with all options for making informed decisions.
Typically, implants are the best option if the natural tooth can’t be saved. However, many dentists will choose extraction following a previous root canal treatment without determining why it failed or whether the benefits of a nonsurgical retreatment can be realized. Sjogren et al12 in a 10-year follow-up study noted that the success rate for retreatment is 98% when the case has no apical periodontitis. Farzaneh et al13 reported in a 4-year follow-up study that the rate can be as high as 86% in cases with apical periodontitis. This article presents nonsurgical retreatment, issues leading to root canal failure, reasons for endodontic failure, and considerations and techniques for retreatment.
Reasons for Root Canal Failure
Endodontic failure occurs for several reasons, which include leaking or poorly sealed restorations, root fractures, untreated canals, inadequately cleaned canals, significant overfills, human error (eg, placement of posts), separated instruments, blocks, ledges, perforations, zips, and transportations.14 In addition, bacteria plaques outside the root, microorganisms such as Enterococcus Faecalis, viruses, yeasts, and foreign bodies may cause failure.15 Practitioners should consider these issues when rendering root canal therapy and retreatment.
Biological, esthetic, clinical, functional, and financial factors must be considered.
· Evaluate periapical and bitewing radiographs to ensure the tooth has a solid bone support.
· Confirm the attachment apparatus is intact unless it is widened due to infection or draining sinus tract.
· Ensure periodontal probing is within normal limits unless a sinus tract is draining from the sulcus.
· Determine if there is a good crown-to-root ratio.
· Ensure no significant mobility or depressibility unless due to a draining sinus tract.
· Assess the strategic value of the tooth.
· Consider remaining tooth structure before and after treatment completed.
· Determine periodontal support.
· Compare costs for retreatment, post/core, and crown, if necessary, to those of implant and crown.
· Communicate the prospects of success and failure.
· Inspire motivation for follow-up visits.
Before retreatment, communicate clearly with the patient and the restorative dentist the diagnosis, prognosis, and treatment options if the tooth cannot be saved. In addition, discuss with the patient that no dental procedure is always successful. When patients are presented with the option of an implant or retreatment of a failing root canal, most would choose retreatment to retain the natural teeth. Retreatment is less invasive, less expensive, and less time consuming than the implant alternative.
A 34-year-old female presented with pain to the dental office. A root canal had been performed 3 months ago by a general dentist. Previous endodontic treatment with acute apical periodontitis was the diagnosis. The patient did not exhibit swelling. She reported taking over-the-counter pain medications but no antibiotics. She had no contributory medical history. Clinically, a crown was present but no visible redness or inflammation around the gingiva. Radigraphically, root canal treatment was evident, with a separated file in the middle of the mesiobuccal (MB) root, short fills on the mesial and distal roots, and a missed distal canal. Periapical lesions were present at the apex of the mesial and distal roots (Figure 4).
The Retreatment Technique
An inferior alveolar nerve block was used with two carpules of 2% xylocaine 1:100,000 epinephrine (Cook-Waite, www.carestreamdental.com). This achieved profound anesthesia for this case.
However, if the nerve block is not sufficient for causing complete anesthesia, infiltration with articaine 1:100,000 epinephrine (Septodont, www.septodontusa.com) can help.