Injury under the influence: A case report

Case presentation

A young adult patient called a practice dental emergency number during the second UK coronavirus lockdown complaining of ‘toothache’ like symptoms, as well as a swollen and painful upper jaw. The patient was triaged on the phone and prescribed a 5-day course of amoxicillin. No improvement was felt the following day, and they presented in person to their dental practice. The patient was a medically fit and well university student who disclosed occasional binge-drinking and was an irregular dental attender with no recent history of dental treatment.

Extra-oral examination revealed diffuse swelling over the right maxilla, which was mildly tender to palpation. Intra-oral examination revealed a minimally restored dentition. The BPE was 101/101. The soft tissues appeared healthy; however, tenderness to palpation was detected in the buccal sulcus adjacent to the upper right second molar. This tooth was also tender to percussion, but unrestored. There were no other signs of endodontic or periodontal disease associated with the upper right premolar/molar teeth. All the upper right premolar/molar teeth responded normally to sensibility testing.

A peri-apical (PA) radiograph was taken by an endodontic specialist (Figure 1). The PA revealed moderate caries in the UR5 (distal) and UR6 (mesial), the peri-radicular and peri-apical tissues appeared to be healthy. As the radiographic examination was inconclusive, a dental panoramic tomograph (DPT) was taken (Figure 2); this showed impacted lower wisdom teeth, and a minimally restored dentition in need of some care. The right maxillary sinus appeared to have a thickened lining.

Justified by the significant swelling and discomfort, and lack of a firm provisional diagnosis, the patient was referred for a small field of view (4 × 4 cm) CBCT scan. Initial viewing of the data failed to show abnormalities in association with the teeth; on further inspection, a ‘foamy’ radiolucency – presumed to be air ‘bubbles’ was identified in the buccal tissues (Figure 3). This led to the observation of a fracture in the lateral sinus wall, with associated thickening of the sinus lining (Figure 3).

A radiographic report from a dentomaxillofacial radiologist subsequently confirmed the findings as a ‘comminuted depressed fracture of anterior right maxillary sinus wall which is not fully imaged’. Thickening of the lining of the sinus lining over the affected area was reported with the remainder of the right maxillary sinus base well pneumatized. The air bubbles in the buccal tissues were identified as ‘traumatic emphysema within the right cheek tissues, primarily in the area buccal to the UL7 and UR8’. These findings were consistent with trauma; entirely unforeseen, given the patient's lack of trauma history.

The patient was informed that the most likely cause of this fracture was a traumatic injury. They seemed astonished by this diagnosis, having denied any knowledge of trauma to the area. The possibility of trauma taking place while inebriated was raised, and only then, with reassurance and futher questioning, did the patient admit to having taken ketamine 1 week prior. It therefore seemed likely that the patient injured themself while under the influence of ketamine.

An urgent maxillofacial surgical opinion was suggested with further imaging of the maxilla and the zygomatic complex with a larger field of view CBCT. However, the patient failed to follow this recommendation, and did not return.

Discussion

Following a clinical examination, intra-oral radiography remains the leading diagnostic modality. However, it suffers anatomical noise because of superimposition of overlying structures, and can be challenging, for example, where the roots of maxillary teeth are long, and the palatal vault is shallow.¹ Panoramic radiography can be helpful, particularly when the structure to be visualized lies within the focal trough of the apparatus. CBCT imaging can assist in complex diagnoses and can be a useful diagnostic aid where other imaging modalities have failed, as in this case. CBCT is becoming increasingly accessible to the general dentist.² In Europe and the UK, those prescribing or reporting the examination must be suitably trained, ideally following the the European Academy of DentoMaxilloFacial Radiology guidelines.³ A key aspect of the reporting process is scrutiny of the entire volume of data,⁴ keeping alert for the presence of unexpected or incidental findings that may extend beyond the area of immediate interest.

First introduced to clinical practice in the 1960s,⁵ ketamine is widely used as an adjunct to local anaesthesia in medicine because it induces general and dissociative anaesthesia (amnesia without complete unconsciousness),⁶ as well as providing analgesia. More recently, multiple high-quality trials have been carried out assessing ketamine for its rapid-onset antidepressant effects, especially in patients with treatment-resistant depression.⁷ When administered by a medical professional, ketamine dosage is carefully monitored and titrated according to the patient's weight, height and age. Ketamine-induced dissociative anaesthesia is achieved in doses ranging from 1 to 2 mg/kg as an intravenous bolus, or 4–11 mg/kg intra-muscularly. Ketamine-induced analgesia is achieved at doses of 0.15–0.25 mg/kg if administered intravenously,⁸ or 0.5–1 mg/kg if intra-muscular.⁹ However, when taken recreationally, the true amount taken may be unknown, and its use is frequently accompanied by alcohol or other substances.¹⁰ Although overdose of ketamine is uncommon, in extreme cases it can lead to respiratory depression and myocardial infarction.¹¹ Ketamine can also cause ataxia, which, when combined with analgesia and sedation, could explain the trauma discussed in this case report. Additionally, the analgesic effects might add to the lack of recall of incident, as the patient have might not felt anything.

Ketamine appeared as a veterinary anaesthetic in 1963¹² and was approved for human use in 1970. Having been used to treat soldiers in the Vietnam war, ketamine abuse escalated, and it rose to popularity as a recreational drug. In 2019, it was found that 3.1% of 16–24-year-olds take the drug recreationally.¹³ A Scottish study found that on average, recreational ketamine users will take around 1/8^th of a gram (125 mg), intranasally, with the resultant effects lasting around an hour.¹⁴ However, with users often already intoxicated, or unaware of the purity of the ketamine being taken, the true amount absorbed is generally unknown. The standard medicinal ketamine dose is around 1–2 mg/kg,¹⁵ meaning the typical recreational dose is above what is recommended in a controlled setting for an average person. Even 3 days after ingestion of ketamine, recreational users could show persisting impaired memory.¹⁶ Additional data are also emerging showing how over the course of the COVID-19 pandemic, feelings of exclusion and isolation may have led to an increase in substance abuse.¹⁷ Substance abuse has been linked to maxillofacial trauma; however, ketamine abuse was not encountered.^18,19 McAllister et al²⁰ found that although illegal drug use was frequently denied in patients presenting with maxillofacial injuries, toxicology testing showed that nearly half (47%) of the patients studied had in fact used illicit drugs.

Conclusion

This case report illustrates the importance of a detailed social history, ideally taken in a face-to-face consultation with an empathetic and reassuring clinician, and highlights a limitation of triage and ‘treatment’ by telephone consultation. The importance of training in the use of CBCT and the reporting of the entire volume of data from a CBCT examination is another important message.