All-on-4 Implant Procedure Leads to Malpractice Claim Against OMS

Marc Leffler, DDS, Esq.
September 22, 2026

Reading time: 7 minutes

Illustration of four dental implants and implant components on a dark blue background.

This real-life OMS case study illustrates how patient anatomy, clinical judgment, and external pressures can turn a complex treatment plan into a malpractice claim. Learn why it’s critical to trust your professional judgment, recommend only viable treatment options, and prioritize patient safety when weighing surgical risks and alternatives.

Key concepts

  • All-on-4 procedure leads to serious complication
  • Trusting your clinical judgment
  • Risk management lessons for implant dentistry

Background facts

R was a 61-year-old generally healthy man who had worn maxillary full dentures for years, but was becoming increasingly dissatisfied with them, both functionally and esthetically. His lower arch posed no problems for him: other than a 3-unit fixed bridge on the right and a 4-unit bridge on the left, he had natural teeth in place. In the past, he was a nearly pack-a-day smoker, but he had since overcome that habit. He presented to a multispecialty dental office he had seen advertised locally, seeking to improve the condition of his maxilla.

He initially saw a prosthodontist, who evaluated the mouth and concluded that an implant-supported prosthesis would work well for R. Per office policy, the on-site oral surgeon would handle the implant aspect of treatment, with the patient then returning to the prosthodontist for the restoration. That same day, the OMS, Dr. G, met with R, ordered a CBCT study, reviewed it, and discussed the available options. Because of the paucity of maxillary bone — especially posteriorly — and “low-lying” maxillary sinus cavities, a traditional implant arrangement would not be possible. So, 2 options were available: (1) perform bilateral sinus lifts with bone grafting, allow for an adequate healing period, place 3 implants (potentially) on each side, and then restore the maxilla prosthetically after osseointegration; or (2) do an all-on-4 procedure using the pterygoid bones bilaterally for both posterior implants, place a provisional prosthetic appliance that same day, and later convert to a permanent prosthesis after integration.

The office management encouraged the most time-efficient case completions possible. With that in mind, Dr. G and the prosthodontist discussed the available options, with Dr. G expressing some concern about the radiographically appearing rather thin pterygoids, particularly on the right side. However, the prosthodontist did not want to wait for the entire sinus lift process to play out, and encouraged the OMS to do the all-on-4 approach, despite her stated concerns. Dr. G (reluctantly) agreed, and so did R, after they had a full discussion about the most common risks, benefits, and options, with R signing a consent form.

On the day of treatment, R took the oral sedative prescribed for him by Dr. G, just before leaving home. Dr. G injected local anesthetic solution buccally and palatally across the entire upper jaw. Because she is left-handed, Dr. G began with her preferred side, the left, because access was easier. Referring to the CBCT images, she uneventfully placed 2 implants on the left side, 1 at the approximate site where tooth #11 had been, and 1 angled into the pterygoid: both were clinically stable. She then turned to the right side to place 2 implants before the prosthodontist placed the ready provisional. The implant near the prior site of the upper right canine was smoothly placed. In performing the right pterygoid osteotomy, Dr. G’s concern came to fruition, as the bur, which had initially been met with typical bony resistance, suddenly fell into a void, which she presumed to be the pterygopalatine fossa. When she backed out the handpiece, bright red, pulsating blood heavily flowed into the mouth, clouding the entire field.

Her initial approach was to pack the site with gauze strips, which did slow the flow, but the gauze quickly filled with blood and continued to do so despite repeated packing. Dr. G believed that she had pierced into (a branch of) the right maxillary artery. With her being unable to gain hemostatic control, and being in an outpatient setting with an awake patient, she attempted to gain access to the source of the bleed by entering the maxillary sinus through a Caldwell-Luc approach, and then cutting a window through the posterior sinus wall to enter the fossa. But doing so only provided a second outlet of significant bleeding, leading her to conclude that ligating the artery required in-hospital care by a head and neck surgeon. R was transported by ambulance to a nearby medical center, with Dr. G accompanying him to try to maintain site pressure as they travelled. R was emergently taken to the OR, where he was induced and intubated, and where an ENT surgeon unsuccessfully attempted access to the torn vessel endoscopically, ultimately ligating the vessel some 2 hours later by way of a preauricular approach infratemporally. R remained in hospital for a week, and missed work for more than a month, left with a scar and always feeling limitations to his usual exercise routine.

Legal action

R’s newly retained attorney obtained all of the relevant dental and medical records, and sent them on to an academic-based OMS for review. That expert passed on his conclusions to the attorney who hired him: that Dr. G succumbed to external pressures and performed a procedure that she knew was concerning and risky, given the specific anatomy presented, and that the preferred set of procedures for this patient would have begun with the sinus lift and graft approach. The attorney also contacted the treating ENT, who was willing to provide his opinion that the bleed and the resultant surgery and after-effects were due to an ill-conceived surgical treatment plan by Dr. G.

Dr. G contacted her malpractice carrier when she provided records to R’s attorney, and again when she was served with papers that initiated the lawsuit against her. She had personally been deeply upset by the events, now some months ago, and she told her assigned attorney that she was eager to put this behind her, partly for the personal impact but also because she realized that she had not exercised her best judgment.

Settlement moves began quickly, with an agreement reached before discovery even started. In addition to money, which covered medical costs, physical and emotional distress, and lost income, R made a somewhat unusual request: that Dr. G write an apology and explanation to him, which he felt that he needed to close the chapter. Despite her attorney advising Dr. G against doing so, explaining the potential impacts upon a Board complaint (which never happened) or hospital credentialing, she did as R had asked, because she, too, needed the closure.

Takeaways

Pressures are placed upon oral surgeons, and in fact many other types of practitioners as well, rather frequently, and they come from sources as diverse as patients, dental or medical colleagues, and practice supervisors and owners. The reasons for the responses to those pressures are equally diverse, from the need to maintain employment, to conflict aversion, to ego. In the end, though, all that really matters on the legal side of practice are adherence to standards of care and principles of ethics. Perhaps, a safe approach for practitioners to take is that if something simply does not feel right, stay away from it. While that might not always be practical, it can at least be an internal starting point, if not ultimately the end point.

It is the general rule, rather than the exception, that there are most often multiple options/alternatives to overcome dental and surgical problems. Principles of informed consent dictate the requirement to advise patients of, among other things, available alternatives. But that does not mean every alternative, only the viable ones. And if an alternative is not viable for any reason, whether because of patient anatomy, underlying patient medical conditions and social habits, or provider limitations (based upon ability or experience), that alternative falls out of the realm of informed consent. Here, the anatomy of R’s right pterygoid and, perhaps (reading between the lines) her own limitations, Dr. G seemingly knew that an all-on-4 plan was not viable for R. Fighting her better judgment was a clear factor in the events and injuries.

All procedures carry risk. It is part and parcel of healthcare delivery, particularly when surgery is involved. Practitioners appropriately take specific risks into account when weighing the potential coming to fruition of those risks against the benefits of doing the procedure. There is no one-size-fits-all formula to use to come to a decision, but instead a subjective process that is individual to every surgeon, considering a host of factors. Many risks come to pass (in the form of injury) in the absence of any negligence, with that concept being a foundation for much of malpractice defense, but when injuries occur because of negligence, that often becomes the very basis for plaintiffs’ cases against doctors.

Decisions about settlement versus trial are extremely case-specific, with the insurer, counsel, and all litigants playing significant roles. Practitioners who have “pure consent” policies are permitted, per policy language, to withhold consent to a settlement, in favor of going to trial. But in cases where practitioners do provide their consent to settle, that does not mean that the malpractice carrier must then settle the case, but simply that it may agree to a settlement. Think of it as a permission slip, but not a requirement slip.

Summary of takeaways

  • External pressures should never outweigh clinical judgment when determining the most appropriate treatment plan.
  • Not every treatment option is suitable for every patient — anatomy, provider experience, and overall risk must be carefully evaluated before proceeding.
  • When complications occur, treatment decisions that fall outside the standard of care can increase liability exposure and lead to malpractice claims.

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In this real-life case study, dentists will see how a billing dispute and incomplete informed consent process escalated into a malpractice lawsuit. Learn why clear communication about treatment risks, accurate coding practices, and thoughtful handling of patient concerns are essential to reducing liability and protecting patient trust.

Key concepts

  • Dentist sued after a billing dispute and nerve injury
  • How informed consent gaps can increase malpractice risk
  • Why accurate coding and patient communication matter

Background facts

For Dr. A, extracting teeth was an everyday part of practice, as was virtually the entire scope of dentistry. In addition to postdoctoral training, she had been performing these procedures for years in a region of the state with no oral surgeons within a 2–3-hour drive. She was a participating provider in several dental insurance plans that were popular among her patients.

One such patient, P, was an 18-year-old high school senior who presented for an annual recall visit, with a new complaint of periodic pain associated with the lower right third molar. Despite P being of majority, his mother accompanied him into the treatment room to see Dr. A. Following a clinical examination, a panoramic film was taken and viewed by Dr. A. Tooth #32 was erupted, had incomplete apex formation, but was still in close radiographic proximity to the inferior alveolar canal. Dr. A assessed the pain to be a function of difficulty in cleansing the area, with inflamed gingivae as a result. She suggested, while pointing to the panoramic, extraction, which she said, "shouldn't be too hard,” although it carried a "slight risk of a nerve injury which could leave P's lower lip and chin numb, and rarely be permanent." This conversation was documented with specificity in the chart. P had heard about impacted wisdom teeth from a few friends, so he asked whether his tooth was impacted. Dr. A replied, "No, it is not.” P wanted to think about it, so he left the office with a sample of an oral rinse and instructions as to how to improve his oral hygiene. A month later, the symptoms persisted, so P's mother called the office to schedule an extraction appointment.

Before having local anesthetic injected, P was handed a paper entitled "consent form,” which he and his mother "briefly read.” The document contained a list of potential risks, including a general statement about possible "loss of sensation.” P signed the document prior to the extraction going forward. Dr. A worked on the tooth for well over an hour, much longer than she had anticipated, cutting out pieces of tooth and trimming away bone using round and fissure burs. P could taste blood, particularly at one point, which caused Dr. A to pack gauze in his mouth. The following day, P awoke to find the right half of his lower lip and chin numb, which he did not find surprising, given the warning beforehand, but so was the right half of his tongue, which was a surprise. At post-op visits, Dr. A assured and re-assured P and his mother that feeling would return to normal — it never did.

Separately, P received a bill for Dr. A's services from her billing office, seeking a co-pay for "#32 7240.” The amount was significant, despite Dr. A's advertised plan participation, so P's mother questioned the office manager as to what all of this meant. The response was that, according to the insurance plan's rules, Dr. A was permitted to charge that amount for fully impacted wisdom teeth, as this was. P's mother replied that Dr. A had specifically advised her and her son that the tooth was not impacted, no less fully so. The office manager spoke with Dr. A, but the answer came back that, because Dr. A had to work so long to remove the tooth, she was not willing to make any adjustments.

P's mother contacted the insurance carrier to explain the situation. The carrier requested a pre-treatment radiograph from Dr. A, based upon which the in-house reviewers concluded that the tooth was not appropriately coded as 7240, but rather should have been 7210 (surgical extraction of erupted tooth). Under the plan provisions, Dr. A was therefore not permitted to charge any co-pay but instead accept the plan payment in full. When the insurer notified Dr. A of that, with a copy sent to P's mother (whose employer provided the coverage), Dr. A was steadfast that she was entitled to the amount billed and would send P to collection if she was not paid. P's mother did pay the claimed balance, but the carrier dropped Dr. A from the panel due to what it referenced as "upcoding resulting in excessive billing.”

Legal action

P had slowly been adapting to the lip, chin, and tongue numbness, but his mother remained upset about the principle of billing her son and threatening a collection action, so she contacted an attorney. The attorney was not very familiar with dentistry in any legal regard, so he reached out to his own dentist, with a copy of Dr. A's records that he had been provided, to help him interpret what was going on. The dentist agreed with the insurance company's position that the extraction had been inappropriately upcoded, but perhaps more importantly that it was clear from the records that, while P had been warned of the possibility of an inferior alveolar nerve injury and its effects, he had not been told anything about tongue numbness, which came from an injury to an entirely different nerve branch and which should have been avoided if proper technique had been employed.

The attorney initiated a lawsuit against Dr. A, asserting lack of informed consent relating to the lingual nerve injury, dental malpractice regarding the causing of the lingual nerve injury, and breach of contract leading to the improperly billed (and collected) co-pay amount. The defense attorneys assigned to Dr. A by her malpractice carrier reviewed the case with their client and advised her that they would seek expert opinion as to the substance of the informed consent and malpractice claims, but that she would not be covered for the breach of contract claim, per a clearly stated policy exclusion.

The expert retained by Dr. A's counsel was provisionally willing to present a defense as to the malpractice claim regarding her having negligently caused the tongue numbness, but that position would need to be re-evaluated following her deposition testimony. However, there was no evidence in the record to demonstrate that she had provided any warning of a potential lingual nerve injury and its impacts. The defense expert did not see a pathway to successfully defend the claim of lack of informed consent. A second expert reviewer reached the same conclusion.

Dr. A's attorneys had a candid discussion with her. Even if the malpractice claim could likely be effectively defended, the lack of informed consent claim could not. So, P would be entitled to a monetary award regardless of which, or both, of the claims went P's way in the eyes of a jury. Dr. A agreed to have her attorneys seek to settle the claim, to be paid by the malpractice carrier, which they did. As part of the settlement agreement, Dr. A would personally return to P the amount his mother paid her for the co-pay. 

Takeaways

While it is impossible to know whether P would have sought an attorney at some point to file an action on his behalf based upon the substantive dental issues, it is quite clear that the issue which drove the initial attorney involvement was the billed, and eventually paid, co-pay amount. There is then perhaps a bit of irony that the money that Dr. A was unwilling to waive directly led to a settled malpractice claim, but that insisted-upon co-pay not only started the legal action steps but was also ultimately paid by Dr. A out-of-pocket. Dr. A made the decision to demand a disputed amount of money, and that decision likely cost her far more — particularly with her being dropped from a panel — than had she acquiesced in the first place. It is not our role here to advise dentists as to whether they should fervently go after unpaid, disputed fees. Instead, we demonstrate a situation where doing so ended up causing more harm than benefit. Food for thought.

Experience teaches that lay jurors might not always understand scientific, dental facts, sometimes making their determinations counter to what experts and attorneys anticipate. On the other hand, issues relating to overbilling or upcoding are relatively straightforward for plaintiffs' attorneys to explain to jurors, and simple for them to understand. At times, jurors might put all else aside and render a verdict for a plaintiff if they do not see the defendant-dentist as having been honest. Such is a version of jury nullification, with the jury members substituting what they deem critical in place of what the law says is critical. Taking subjectivity of that type out of the hands of juries increases a defendant's chances for success.

This case study exemplifies how the trigger for a patient seeking legal counsel might have nothing at all to do with the quality of dentistry. Yes, dentistry is complex, and there is an ever-present unpredictability factor, so ideal results do not happen with every procedure, with every patient. What need not be complex are matters over which dentists and their staff members have full control — such matters can virtually always be taken out of the equation as to what starts the legal ball rolling.

Finally, we briefly address the coding of procedures for billing purposes. The ADA and perhaps other associations provide numerical codes for dental procedures, which state the procedure performed and which often serve as the basis for which payment is sought and made. With few exceptions — such as 7241 for full impactions with unusual surgical complications, or time under sedation/general anesthesia, as examples — procedure codes do not take into account the length of time required to complete or the difficulty in doing so. To upcode to a procedure not actually performed, for a higher fee, is to invite a host of problems, including the initiation of a malpractice lawsuit or Dental Board complaint.

Summary of takeaways

  • A signed consent form alone is not enough — patients should be informed of all risks associated with a procedure, and those discussions should be thoroughly documented.
  • Billing disputes and inaccurate procedure coding can damage patient trust and may become the catalyst for malpractice claims.
  • Upcoding procedures can result in payer disputes, loss of network participation, regulatory concerns, and increased legal exposure.
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In this real-life case study, oral and maxillofacial surgeons will learn how coding decisions and informed consent gaps can create significant liability risks. Discover why accurate billing, clear patient communication, and thorough consent discussions are essential risk management tools.

Key concepts

  • OMS sued following an upcoding dispute and nerve injury
  • How billing and coding decisions affect malpractice risk
  • The importance of documenting consent discussions beyond a signed form

Background facts

For Dr. C, an oral and maxillofacial surgeon, extracting teeth was an everyday part of practice. As the only oral surgeon within a 2–3-hour drive, she was a participating provider in a number of dental insurance programs which were more popular within her patient and referral bases.

One such patient, T, was an 18-year-old high school senior who self-presented based upon a network list, with a new complaint of periodic pain associated with the lower right third molar. Despite T being of majority, his mother accompanied him into the treatment room to see Dr. C. Following a clinical examination, a panoramic film was taken and viewed by Dr. C. Tooth #32 was erupted, had incomplete apex formation, but was still in close radiographic proximity to the inferior alveolar canal. Dr. C assessed the pain to be a function of difficulty in cleansing the area, with inflamed gingivae as a result. She suggested, while pointing to the panoramic, extraction, which she said, "shouldn't be too hard,” although it carried a "slight risk of a nerve injury which could leave T's lower lip and chin numb, and rarely be permanent." This conversation was documented with specificity in the chart. T had heard about impacted wisdom teeth from a few friends, so he asked whether his tooth was impacted. Dr. C replied, "No, it is not.” T wanted to think about it, so he left the office with a sample of an oral rinse and instructions as to how to improve his oral hygiene, particularly in that area of the mouth. A month later, the symptoms persisted, so T's mother called the office to schedule an extraction appointment.

Before having local anesthetic injected, T was handed a paper entitled "consent form,” which he and his mother "briefly read.” The document contained a list of potential risks, including a general statement about possible "loss of sensation.” T signed the document prior to the extraction going forward. Dr. C worked on the tooth for nearly an hour, much longer than she had anticipated, cutting out pieces of tooth and trimming away bone using round and fissure burs. T could taste blood, particularly at one point which caused Dr. C to pack gauze in his mouth. The following day, T awoke to find the right half of his lower lip and chin numb, which he did not find surprising, given the warning beforehand, but so was the right half of his tongue, which was a surprise. At post-op visits, Dr. C assured and re-assured T and his mother that feeling would return to normal — it never did.

Separately, T received a bill for Dr. C's services from her billing office, seeking a co-pay for "#32 7240.” The amount was significant, despite Dr. C's advertised plan participation, so T's mother questioned the office manager as to what all of this meant. The response was that, according to the insurance plan's rules, Dr. C was permitted to charge that amount for fully impacted wisdom teeth, as this was. T's mother replied that Dr. C had specifically advised her and her son that the tooth was not impacted, no less fully so. The office manager spoke with Dr. C, but the answer came back that, because Dr. C had to work so long to remove the tooth, she was not willing to make any adjustments.

T's mother contacted the insurance carrier to explain the situation. The carrier requested a pre-treatment radiograph from Dr. C, based upon which the in-house reviewers concluded that the tooth was not appropriately coded as 7240, but rather should have been 7210 (surgical extraction of erupted tooth). Under the plan provisions, Dr. C was therefore not permitted to charge any co-pay but instead accept the plan payment in full. When the insurer notified Dr. C of that, with a copy sent to T's mother (whose employer provided the coverage), Dr. C was steadfast that she was entitled to the amount billed and would send T to collection if she was not paid. T's mother did pay the claimed balance, but the carrier dropped Dr. C from the panel due to what it referenced as "upcoding resulting in excessive billing.”

Legal action

T had slowly been adapting to the lip, chin and tongue numbness, but his mother remained upset about the principle of billing her son and threatening a collection action, so she contacted an attorney. The attorney was not very familiar with oral surgery in any legal regard, so he reached out to his own dentist, with a copy of Dr. C's records that he had been provided, to help him interpret what was going on. This state did not require specialty-specific experts. The dentist agreed with the insurance company's position that the extraction had been inappropriately upcoded, but perhaps more importantly that it was clear from the records that, while T had been warned of the possibility of an inferior alveolar nerve injury and its effects, he had not been told anything about tongue numbness, which came from an injury to an entirely different nerve branch and which should have been avoided if proper technique had been employed. (As a side note, the general phrase in the consent form, "loss of sensation,” did not provide any expert reviewer with the specificity that is helpful in a defense.)

The attorney initiated a lawsuit against Dr. C, asserting lack of informed consent relating to the lingual nerve injury, dental malpractice regarding the causing of the lingual nerve injury, and breach of contract leading to the improperly billed (and collected) co-pay amount. The defense attorneys assigned to Dr. C by her malpractice carrier reviewed the case with their client and advised her that they would seek expert opinion as to the substance of the informed consent and malpractice claims, but that she would not be covered for the breach of contract claim, per a clearly stated policy exclusion.

The expert retained by Dr. C's counsel was provisionally willing to present a defense as to the malpractice claim regarding her having negligently caused the tongue numbness — but that position would need to be re-evaluated following her deposition testimony. However, there was no evidence in the record to demonstrate that she had provided any warning of a potential lingual nerve injury and its impacts. The defense expert did not see a pathway to successfully defend the claim of lack of informed consent. A second expert reviewer reached the same conclusion.

Dr. C's attorneys had a candid discussion with her. Even if the malpractice claim could likely be effectively defended, the lack of informed consent claim could not. So, T would be entitled to a monetary award regardless of which, or both, of the claims went T's way in the eyes of a jury. Dr. C agreed to have her attorneys seek to settle the claim, to be paid by the malpractice carrier, which they did. As part of the settlement agreement, Dr. C would personally return to T the amount his mother paid her for the co-pay. 

Takeaways

While it is impossible to know whether T would have sought an attorney at some point to file an action on his behalf based upon the substantive oral surgery issues, it is quite clear that the issue which drove the initial attorney involvement was the billed, and eventually paid, co-pay amount. There is then perhaps a bit of irony that the money that Dr. C was unwilling to waive directly led to a settled malpractice claim, but that insisted-upon co-pay not only started the legal action steps but was also ultimately paid by Dr. C out-of-pocket. Dr. C made the decision to demand a disputed amount of money, and that decision likely cost her far more — particularly with her being dropped from a panel - than had she acquiesced in the first place. It is not our role here to advise oral surgeons as to whether they should fervently go after unpaid, disputed fees. Instead, we demonstrate a situation where doing so ended up causing more harm than benefit. Food for thought.

Experience teaches that lay jurors might not always understand scientific, dental/surgical facts, sometimes making their determinations counter to what experts and attorneys anticipate. On the other hand, issues relating to overbilling or upcoding are relatively straightforward for plaintiffs' attorneys to explain to jurors, and simple for them to understand. At times, jurors might put all else aside and render a verdict for a plaintiff if they do not see the defendant-dentist as having been honest. Such is a version of jury nullification, with the jury members substituting what they deem critical, in place of what the law says is critical. Taking subjectivity of that type out of the hands of juries increases a defendant's chances for success.

This case study exemplifies how the trigger for a patient seeking legal counsel might have nothing at all to do with the quality of surgery performed. Yes, oral surgery is complex, and there is an ever-present unpredictability factor, so ideal results do not happen with every procedure, with every patient. What need not be complex are matters over which surgeons and their staff members have full control; such matters can virtually always be taken out of the equation as to what starts the legal ball rolling.

Finally, we briefly address the coding of procedures for billing purposes. The ADA and perhaps other associations provide numerical codes for dental procedures, which state the procedure performed and which often serve as the basis for which payment is sought and made. With few exceptions — such as 7241 for full impactions with unusual surgical complications, or time under sedation/general anesthesia, as examples — procedure codes do not take into account the length of time required to complete or the difficulty in doing so. To upcode to a procedure not actually performed, for a higher fee, is to invite a host of problems, including the initiation of a malpractice lawsuit or Dental Board complaint.

Summary of takeaways

  • A billing dispute can quickly escalate into legal action, even when the original concern is not directly related to clinical care.
  • Accurate coding matters because upcoding or disputed fees can damage patient trust and increase liability risk.
  • Clear, specific informed consent documentation helps support a stronger defense if complications occur.

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In this real-life case study, oral and maxillofacial surgeons will learn why informed consent is a critical part of surgical risk management—not just a formality. Understand how consent gaps, documentation limitations, and differing standards of care can affect malpractice claims, especially for newer practitioners or those working outside their own offices.

Key concepts

  • Why informed consent is more than a formality
  • How consent gaps can lead to malpractice claims
  • The importance of documenting surgical risk discussions

Background facts

Dr. G was an oral and maxillofacial surgery resident, in the third of six years of training. She spent most of her current time on off-service rotations, so she was able to moonlight outside of the hospital, which was a practice permissible in her program. To properly protect herself, Dr. G obtained malpractice insurance, which allowed for part-time non-resident work; inasmuch as she was not yet an oral surgeon, her premium was set as would be done for a general dentist performing oral surgery.

On a typical day in the busy, urban dental office, Dr. G generally treated between 10 and 15 patients, performing the extraction of impacted and non-impacted teeth, with an occasional root resection, apicoectomy, or biopsy. R, a 22-year-old man, presented with an episodically symptomatic, deeply impacted lower left third molar; he was directed to see Dr. G for evaluation and potential treatment. On the panoramic film that Dr. G reviewed, tooth #17 was fully imbedded in bone, with a mesioangular inclination so as to create a clinically-evident periodontal defect on the distal aspect of the adjacent second molar. Dr. G suggested to R that the wisdom tooth be extracted, with a bone graft placed into the socket. Because of the radiographic relationships that were visible and noted, clear warning was given about the realistic potential for left inferior alveolar nerve injury, and those effects, but little else was provided in terms of risks, even according to Dr. G's chart entry. The office had no written consent forms.

Under local anesthesia, Dr. G sectioned the tooth, taking note as she proceeded of the angulation of the crown toward the lingual. Exercising appropriate care to surgically stay away from the lingual plate and gingiva, the tooth was removed in sections, seemingly uneventfully; but as the crown portion was elevated out, what appeared to be an intact lingual nerve became visible immediately above the height of bone. The site was carefully debrided and irrigated, with a small amount of bone graft material placed just behind tooth #18. Because of Dr. G's hospital schedule, she knew that she would not be able to return to the office for 2 weeks, so she placed a chromic gut suture and advised R to return if he had any problems. Dr. G wrote a detailed chart entry, chronicling every surgical step and including her findings regarding the lingual nerve.

R never returned, and nobody from the office, including Dr. G, attempted to contact him: because of the large patient volume, post-treatment calls were not very feasible, given the few administrative staff members.

Legal action

No word was heard from or about R until the office received a letter, some 10 months after treatment, from an attorney representing R. The letter requested complete copies of R's records; the office complied but did not inform Dr. G of the request or compliance. Approximately 3 months later, a process server appeared at the hospital's oral surgery clinic and handed Dr. G a copy of the papers initiating a lawsuit against her. The Complaint alleged professional negligence — dental malpractice — for improper surgery that resulted in left-sided tongue numbness and taste loss, as well as lack of informed consent. After gathering her thoughts, she contacted her malpractice insurance carrier, forwarded what she was given, asked the office to forward to her carrier a copy of R's office records, and was ultimately contacted by the attorneys hired to represent her.

In the first lawyer-client meeting, the litigation process was discussed with Dr. G. In turn, Dr. G described her surgical technique, as had been documented, which sounded "textbook" to her attorney, who was well-experienced in defending dental malpractice cases. The attorney expressed concern about there being no written consent form, compounded by the limited statement of risks in the chart entry, which ignored injury to the lingual nerve and, by extension, the chorda tympani. At the conclusion of the meeting, the attorney discussed his next immediate steps, which included obtaining a very preliminary expert review from a general dentist who performed many extractions. (The State in which the lawsuit was filed required that all experts be of the same area of practice as the defendant; because Dr. G was still in training, she was a general dentist.)

Pending depositions and other discovery, the potential expert supporting Dr. G was of the opinion that her description of the surgery lacked any defects, with the resulting injury being a function of the anatomic relationships at play, namely the tilt toward and proximity of the crown to the lingual nerve complex. As to the issue of lack of informed consent, the expert's opinion was that, in the world of general dentists, although not oral surgeons, written consent forms for surgical procedures were the exception rather than the rule, and risk discussions by general dentists, although not by oral surgeons, were usually quite limited, with Dr. G's documented risk statement falling well within that general-dentist-based parameter. 

Discovery proceeded with no surprises and no changes in defense expert opinion. All involved prepared for trial, with disclosures of anticipated expert testimony shared. On the first day of trial, but before seating the jury, R's (plaintiff's) counsel made a motion in limine — a pretrial request to exclude certain testimony or other evidence — to bar Dr. G's expert from setting forth standards of care, regarding surgical technique, informed consent, or otherwise, that were different as between general dentists and oral surgeons. If successful, Dr. G's expert would not be able to argue that Dr. G, as a general dentist (in reality), should not be held to meet the informed consent standard of care of oral surgeons regarding written consent forms and the extent of surgical risks discussed with R.

The trial judge ruled that Dr. G's expert would not be able to draw the distinction planned between oral surgeons and other dentists. In short, the court said that it is the procedure, not the practitioner, that carries the standard of care. Allowing for such differences would prejudice patients such that those having surgery performed by dentists who are not oral surgeons would essentially be signing on to a lesser level of care, which would not be proper. Dr. G remained confident that she had performed the surgery appropriately in all respects, but she understood the implications of the court's decision as it related to her obtaining of informed consent from R, namely that her process did not meet the standard for the procedure. She agreed to try to reach a settlement, and that was accomplished before the first words were spoken at trial.

Takeaways

The ruling by the judge in this isolated case is one that is quite commonly, although not necessarily universally, adopted by courts. As stated here, the basis for that is the protection of patient safety, a frequent theme of many court decisions on any number of issues. The lesson, though, is clear: any practitioner who undertakes any procedure should understand that their actions in doing so will be held to the standards of experienced practitioners with focused training. Oral surgeons might well read this concept and reason that it does not affect them, given their superior training; but the application to oral surgeons is most relevant to newer practitioners who, despite their strong academic backgrounds, simply do not have very much in-practice experience. That comes with time and repetition, with a learning curve to get there. 

As we have discussed in other case studies, the impact of lack of informed consent is often underestimated, but it ought not be that way. Here, Dr. G committed no malpractice surgically, at least as the description describes, but the informed consent process fell short, with that alone leading to a result for the plaintiff. The informed consent process is far more than just a throwaway to check off a box, but rather an integral part of surgery, with ramifications of deficiencies having the same ultimate litigation effect as negligently carried out surgery. 

While this case study does not directly address the propriety of a panoramic radiograph as compared with a 3-D imaging study such as a CBCT, it is the proverbial elephant in the room. It would be hard to disagree with the concept that 3-D imaging is preferred so as to help in identifying anatomic relationships and potential hazards. But whether use of a CBCT constitutes standard of care will ultimately boil down to dueling opinions of experts for the plaintiff and the defendant, both subject to cross-examination. Standards of care are not published, but if they were, it would be unlikely to see such a publication make its way into trial evidence, for the reason based upon the age-old attorney mantra that a lawyer cannot cross-examine a piece of paper. As of this point in time, opposing experts strongly sit on both sides of the issue regarding the type of imaging appropriate for a given situation, and that is where the world of litigation will remain, at least for the near future. Oral surgeons would do well to determine for themselves what their judgment of choice is, and have a solid line of reasoning to support it.

Moonlighting residents and newer oral surgeons who travel between offices, often not their own, face a number of challenges to go along with the benefits. Weighing them has surgical-legal implications that might not become apparent until years after the fact.

Summary of takeaways

  • Practitioners are held to the standard of care for the procedure performed, regardless of their training level or practice designation.
  • Informed consent is a critical part of surgical care, and deficiencies in the process can carry significant malpractice risk.
  • Oral surgeons, residents, and traveling practitioners should carefully evaluate imaging decisions, documentation practices, and office processes before performing procedures.

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In this real-life case study, dentists will see how a billing dispute and incomplete informed consent process escalated into a malpractice lawsuit. Learn why clear communication about treatment risks, accurate coding practices, and thoughtful handling of patient concerns are essential to reducing liability and protecting patient trust.

Key concepts

  • Dentist sued after a billing dispute and nerve injury
  • How informed consent gaps can increase malpractice risk
  • Why accurate coding and patient communication matter

Background facts

For Dr. A, extracting teeth was an everyday part of practice, as was virtually the entire scope of dentistry. In addition to postdoctoral training, she had been performing these procedures for years in a region of the state with no oral surgeons within a 2–3-hour drive. She was a participating provider in several dental insurance plans that were popular among her patients.

One such patient, P, was an 18-year-old high school senior who presented for an annual recall visit, with a new complaint of periodic pain associated with the lower right third molar. Despite P being of majority, his mother accompanied him into the treatment room to see Dr. A. Following a clinical examination, a panoramic film was taken and viewed by Dr. A. Tooth #32 was erupted, had incomplete apex formation, but was still in close radiographic proximity to the inferior alveolar canal. Dr. A assessed the pain to be a function of difficulty in cleansing the area, with inflamed gingivae as a result. She suggested, while pointing to the panoramic, extraction, which she said, "shouldn't be too hard,” although it carried a "slight risk of a nerve injury which could leave P's lower lip and chin numb, and rarely be permanent." This conversation was documented with specificity in the chart. P had heard about impacted wisdom teeth from a few friends, so he asked whether his tooth was impacted. Dr. A replied, "No, it is not.” P wanted to think about it, so he left the office with a sample of an oral rinse and instructions as to how to improve his oral hygiene. A month later, the symptoms persisted, so P's mother called the office to schedule an extraction appointment.

Before having local anesthetic injected, P was handed a paper entitled "consent form,” which he and his mother "briefly read.” The document contained a list of potential risks, including a general statement about possible "loss of sensation.” P signed the document prior to the extraction going forward. Dr. A worked on the tooth for well over an hour, much longer than she had anticipated, cutting out pieces of tooth and trimming away bone using round and fissure burs. P could taste blood, particularly at one point, which caused Dr. A to pack gauze in his mouth. The following day, P awoke to find the right half of his lower lip and chin numb, which he did not find surprising, given the warning beforehand, but so was the right half of his tongue, which was a surprise. At post-op visits, Dr. A assured and re-assured P and his mother that feeling would return to normal — it never did.

Separately, P received a bill for Dr. A's services from her billing office, seeking a co-pay for "#32 7240.” The amount was significant, despite Dr. A's advertised plan participation, so P's mother questioned the office manager as to what all of this meant. The response was that, according to the insurance plan's rules, Dr. A was permitted to charge that amount for fully impacted wisdom teeth, as this was. P's mother replied that Dr. A had specifically advised her and her son that the tooth was not impacted, no less fully so. The office manager spoke with Dr. A, but the answer came back that, because Dr. A had to work so long to remove the tooth, she was not willing to make any adjustments.

P's mother contacted the insurance carrier to explain the situation. The carrier requested a pre-treatment radiograph from Dr. A, based upon which the in-house reviewers concluded that the tooth was not appropriately coded as 7240, but rather should have been 7210 (surgical extraction of erupted tooth). Under the plan provisions, Dr. A was therefore not permitted to charge any co-pay but instead accept the plan payment in full. When the insurer notified Dr. A of that, with a copy sent to P's mother (whose employer provided the coverage), Dr. A was steadfast that she was entitled to the amount billed and would send P to collection if she was not paid. P's mother did pay the claimed balance, but the carrier dropped Dr. A from the panel due to what it referenced as "upcoding resulting in excessive billing.”

Legal action

P had slowly been adapting to the lip, chin, and tongue numbness, but his mother remained upset about the principle of billing her son and threatening a collection action, so she contacted an attorney. The attorney was not very familiar with dentistry in any legal regard, so he reached out to his own dentist, with a copy of Dr. A's records that he had been provided, to help him interpret what was going on. The dentist agreed with the insurance company's position that the extraction had been inappropriately upcoded, but perhaps more importantly that it was clear from the records that, while P had been warned of the possibility of an inferior alveolar nerve injury and its effects, he had not been told anything about tongue numbness, which came from an injury to an entirely different nerve branch and which should have been avoided if proper technique had been employed.

The attorney initiated a lawsuit against Dr. A, asserting lack of informed consent relating to the lingual nerve injury, dental malpractice regarding the causing of the lingual nerve injury, and breach of contract leading to the improperly billed (and collected) co-pay amount. The defense attorneys assigned to Dr. A by her malpractice carrier reviewed the case with their client and advised her that they would seek expert opinion as to the substance of the informed consent and malpractice claims, but that she would not be covered for the breach of contract claim, per a clearly stated policy exclusion.

The expert retained by Dr. A's counsel was provisionally willing to present a defense as to the malpractice claim regarding her having negligently caused the tongue numbness, but that position would need to be re-evaluated following her deposition testimony. However, there was no evidence in the record to demonstrate that she had provided any warning of a potential lingual nerve injury and its impacts. The defense expert did not see a pathway to successfully defend the claim of lack of informed consent. A second expert reviewer reached the same conclusion.

Dr. A's attorneys had a candid discussion with her. Even if the malpractice claim could likely be effectively defended, the lack of informed consent claim could not. So, P would be entitled to a monetary award regardless of which, or both, of the claims went P's way in the eyes of a jury. Dr. A agreed to have her attorneys seek to settle the claim, to be paid by the malpractice carrier, which they did. As part of the settlement agreement, Dr. A would personally return to P the amount his mother paid her for the co-pay. 

Takeaways

While it is impossible to know whether P would have sought an attorney at some point to file an action on his behalf based upon the substantive dental issues, it is quite clear that the issue which drove the initial attorney involvement was the billed, and eventually paid, co-pay amount. There is then perhaps a bit of irony that the money that Dr. A was unwilling to waive directly led to a settled malpractice claim, but that insisted-upon co-pay not only started the legal action steps but was also ultimately paid by Dr. A out-of-pocket. Dr. A made the decision to demand a disputed amount of money, and that decision likely cost her far more — particularly with her being dropped from a panel — than had she acquiesced in the first place. It is not our role here to advise dentists as to whether they should fervently go after unpaid, disputed fees. Instead, we demonstrate a situation where doing so ended up causing more harm than benefit. Food for thought.

Experience teaches that lay jurors might not always understand scientific, dental facts, sometimes making their determinations counter to what experts and attorneys anticipate. On the other hand, issues relating to overbilling or upcoding are relatively straightforward for plaintiffs' attorneys to explain to jurors, and simple for them to understand. At times, jurors might put all else aside and render a verdict for a plaintiff if they do not see the defendant-dentist as having been honest. Such is a version of jury nullification, with the jury members substituting what they deem critical in place of what the law says is critical. Taking subjectivity of that type out of the hands of juries increases a defendant's chances for success.

This case study exemplifies how the trigger for a patient seeking legal counsel might have nothing at all to do with the quality of dentistry. Yes, dentistry is complex, and there is an ever-present unpredictability factor, so ideal results do not happen with every procedure, with every patient. What need not be complex are matters over which dentists and their staff members have full control — such matters can virtually always be taken out of the equation as to what starts the legal ball rolling.

Finally, we briefly address the coding of procedures for billing purposes. The ADA and perhaps other associations provide numerical codes for dental procedures, which state the procedure performed and which often serve as the basis for which payment is sought and made. With few exceptions — such as 7241 for full impactions with unusual surgical complications, or time under sedation/general anesthesia, as examples — procedure codes do not take into account the length of time required to complete or the difficulty in doing so. To upcode to a procedure not actually performed, for a higher fee, is to invite a host of problems, including the initiation of a malpractice lawsuit or Dental Board complaint.

Summary of takeaways

  • A signed consent form alone is not enough — patients should be informed of all risks associated with a procedure, and those discussions should be thoroughly documented.
  • Billing disputes and inaccurate procedure coding can damage patient trust and may become the catalyst for malpractice claims.
  • Upcoding procedures can result in payer disputes, loss of network participation, regulatory concerns, and increased legal exposure.
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Additional Risk Tips content

See how a billing dispute, upcoding concerns, and informed consent gaps led to a dental malpractice lawsuit and costly legal consequences.

Learn how upcoding disputes and informed consent gaps can lead to OMS malpractice claims, patient distrust, and legal action.

Oral and maxillofacial surgeons can learn how informed consent gaps, documentation issues, and procedure-based standards of care may contribute to OMS malpractice claims.

This document does not constitute legal or medical advice and should not be construed as rules or establishing a standard of care. 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.

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