Malpractice Minute

Dentist Misjudges Bone Height During Implant Placement, Resulting in Damage to the Inferior Alveolar Nerve; Malpractice Lawsuit Follows

Mario Catalano, DDS, MAGD – July 2021

Introduction

Every new dentist faces the same dilemma: there is no replacement for experience. As new dentists settle into practice, hopefully they understand their own limitations, as well as the limitations of the techniques and equipment they use in practice. Adopting a conservative approach, especially in one’s early days of practice, may be beneficial.

However, the practice of dentistry is dynamic. The seasoned as well as the new practitioner should not just settle into a certain way of doing things, while ignoring the inevitable changes in the standard of care. As new knowledge and techniques become available, the dentist must consider whether and when it is appropriate to incorporate them into one’s practice. However, that balance between currency and credibility is not always easy to maintain.

Case Discussion
Dr. C maintained a general dental practice that focused heavily on dental implants (both placement and restoration) and the use of lasers to treat various oral conditions. Dr. C had recently hired Dr. K, a recent dental school graduate, as an associate. Because of the practice’s emphasis, Dr. K was sent to several weekend courses on these techniques and Dr. C mentored him as he began practice.

A 51-year-old woman presented to the practice as a new patient, wishing to explore her options regarding her missing tooth number 19. The case was assigned to Dr. K, who began by taking a set of full mouth X-rays and conducting a thorough oral examination. Dr. K’s reading of the X-rays indicated there was 9 mm of bone superior to the inferior alveolar canal (IAC). Choosing to be cautious, Dr. K suggested to the patient the options of either an 8 mm implant or a traditional 3-unit bridge. Following a thorough discussion of the recognized risks and expected benefits of each option, the patient opted for the implant. Because this was a single, apparently uncomplicated implant case, Dr. C decided Dr. K should handle it.

On the day of surgery, the patient signed an appropriate informed consent form that reiterated the risks and benefits previously discussed, including the possibility of inferior alveolar nerve (IAN) paresthesia. Dr. K also assured the patient that the 1 mm margin allowed for between the implant depth and the IAN canal should provide a “safety zone” to account for any discrepancies between the X-ray and the actual bony structure.

After the induction of local anesthesia, Dr. K began the series of sequential osteotomies for implant placement. During this process, Dr. K suddenly felt a decrease in resistance to the drilling, which he attributed to poor bone quality. He proceeded with the preparation and completed the implant placement.

He then reviewed the case with Dr. C, including the lack of resistance he thought he felt. Dr. C suggested a postsurgical X-ray, which indicated that the implant had invaded the IAN canal. This finding explained the lack of resistance.

The patient was informed of what had transpired, and the implant was immediately removed and bone graft material was placed at the osteotomy site. Dr. K explained that the IAN would likely be numb for a period of time. He also recommended to commence treatment of the nerve with low level laser therapy (LLLT) to stimulate healing and restore function (LLLT is not Food and Drug Administration [FDA]-approved for this application). The patient consented, and LLLT treatment was commenced that day.

Dr. K followed the patient closely over the next 18 months, providing approximately 30 LLLT treatments and documenting his subjective assessment of slight improvement after each treatment. However, Dr. K never conducted any nerve mapping or other objective measurement of nerve function.

Eventually, the patient became dissatisfied with her progress and sought a second opinion from an oral and maxillofacial surgeon (OMS). The surgeon indicated that the therapeutic window had passed and little could be done to improve her current condition. She also noted that X-rays showed bone fragments close to the IAN.

The patient sued both dentists charging that they had prepared for the original procedure improperly (by failing to take a cone-beam computed tomography [CBCT]), performed the procedure improperly (by using an implant too long), and failed to appropriately refer her to an OMS or neurologist in a timely manner, thereby preventing her benefiting from prompt remedial treatment.

Several potential defense experts reviewed the case for the doctors’ insurance carrier; however, none of them could support the care. Additionally, the expert reviews of this case questioned the appropriateness of the immediate bone grafting after the implant was removed. The case against both doctors was settled by a payment to the patient.

Risk Management Considerations

Theodore Passineau, JD, HRM, RPLU, CPHRM, FASHRM

This case provides an opportunity to discuss the dynamic nature of the practice of dentistry from two perspectives: the evolution of currently performed procedures and the introduction of new therapeutic modalities.

The limitations of radiographs have long been recognized. As CBCT has become more available and less expensive, its use as part of the implant placement process has become more widely accepted, especially when placement will be near the IAN or maxillary sinus. When the use of CBCT becomes the standard of care is difficult to say, but the dentist needs to consider it in all appropriate cases.

The use of any unapproved therapy also requires careful consideration. While the off-label use of medications or the use of not-yet-FDA-approved implants is (in some cases) within the standard of care in medicine, when it is done, the patient must be very thoroughly counseled and informed that the therapy is not approved by FDA. This advisement is accomplished through the informed consent process.

Whatever treatment is rendered, the dentist (however long he or she has been practicing) must be fully competent to perform the procedure and manage any reasonably anticipated complications. A savvy dentist knows and accepts her or his limitations. If the case starts to “go off the rail,” an early referral to someone with appropriate expertise is likely to inure to the patient’s benefit, and hopefully will minimize the referring dentist’s potential professional liability exposure. Along the way, all dentists participating in a patient’s care should take occasional “timeouts” to assess whether the case is progressing as it should.

Informed consent to treatment was not an issue in this case; however, it is important to understand what informed consent is and isn’t. Informed consent is when the patient is educated about the recognized risks, expected benefits, and reasonable alternatives to the proposed treatment so that he or she can make an informed decision about whether to proceed with treatment. In consenting, patients are assuming the risks that have been explained to them; however, they are never consenting to care below the standard of care.

Summary Suggestions
The following suggestions may be useful when providing higher risk or unconventional dental treatment:

  • Clinical competency is a must. If the dentist is not completely familiar with the condition, its treatment, and the possible complications, he or she should promptly refer the case to a provider with more specific expertise to address treatment needs or complications.
  • Clinical competency is not a static state. Dentists must devote sufficient time and attention to completing continuing dental education (CDE) and other information that will keep them current with the state of practice.
  • If an experimental or unapproved treatment is proposed, the dentist must clearly explain the experimental or unproven nature of the procedure to the patient as part of the informed consent process.

Conclusion
Because of ongoing research and development, the accuracy, efficiency, and efficacy of dentistry has never been at a higher level. However, it remains an inexact science. New potential or actual risks may emerge with every new product or technique. So, dentists should continually increase their knowledge, skill, and attention to detail in response to new developments.


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This document should not be construed as medical or legal advice. Because the facts applicable to your situation may vary, or the laws applicable in your jurisdiction may differ, please contact your attorney or other professional advisors if you have any questions related to your legal or medical obligations or rights, state or federal laws, contract interpretation, or other legal questions.