Diagnostic Assessment — Pericoronitis
Example 1 of 1 · fictitious patient (Veteran DH)
Diagnostic Assessment
Pericoronitis
No Statement of Principles applies to this condition (non-SOP claim).
ADF History
Veteran DH, date of birth 19 July 1995, Australian Army, Rifleman (infantry soldier), enlisted 04 February 2013, discharged at his own request 30 September 2021. Operational service: Iraq (partner force training mission), 10 November 2017 to 15 June 2018 (warlike).
Occupational History
As an infantry soldier the veteran conducted field exercises lasting one to three weeks, with limited water for washing and oral hygiene, long periods of sleep deprivation on piquet and patrol duties, and reliance on high-sugar ration packs and caffeine. Smoking was common among junior soldiers in the field and on deployment, where cigarettes were cheap and used to manage boredom, fatigue and stress.
On deployment to a partner force training base in Iraq, soldiers were exposed to rocket and indirect fire attacks, dust storms, extreme temperature, shift-based force protection duties and recurrent respiratory infections in shared accommodation. Dental care in theatre was limited to periodic visits by a dental officer, with definitive oral surgery available only at a distant role 2 or role 3 facility.
History
Veteran DH, an infantry soldier in the Australian Army whose partially erupted lower right third molar had been listed for removal before deployment but not removed, developed acute pericoronitis of the lower right third molar on 24 February 2018 on warlike service in Iraq, after a rocket attack, weeks of sleep deprivation, tonsillitis, a course of prednisolone, heavy smoking and a week without oral hygiene on a field activity. The condition worsened to a pericoronal abscess with spreading submandibular infection on 18 March 2018, requiring evacuation, incision and drainage and extraction of both right third molars.
Timeline
- 04 Feb 2013 — The veteran enlisted in the Australian Army aged 17 years and 6 months. The entry dental examination recorded good oral hygiene, no caries and unerupted third molars, with no symptoms. He was a non-smoker. "dentally fit, third molars unerupted"
- 14 Aug 2017 — At his pre-deployment dental examination the dental officer recorded a partially erupted, mesioangularly impacted lower right third molar covered posteriorly by a gum flap (operculum), with food trapping, and a supra-erupted upper right third molar biting onto the flap. Removal of both teeth before deployment was recommended. The surgery could not be scheduled before he deployed and he was deployed with a waiver. He had smoked about 15 cigarettes a day since 2014. "partially erupted 48, recommend extraction"
- 05 Feb 2018 — On warlike service in Iraq, the base came under rocket attack while the veteran was on force protection duty. A rocket impacted about 60 metres from his position and he sheltered in a bunker for four hours. He described ongoing fear of further attacks and was sleeping three to four hours a night between force protection shifts through February. "rocket attack, shaken, poor sleep"
- 12 Feb 2018 — He was seen at the role 1 facility with fever, sore throat and exudative tonsillitis, and with a dust-related exacerbation of asthma. Phenoxymethylpenicillin was prescribed, and prednisolone 50 mg daily was given for five days, to 16 February 2018. From 16 to 23 February 2018 he accompanied the partner force on a field activity with severe water restrictions, during which his toiletries were lost and he could not brush his teeth for seven days. "tonsillitis, prednisolone 50 mg"
- 25 Feb 2018 — He presented to the role 1 facility with pain behind the lower right back teeth since 24 February 2018, swelling of the gum flap over the lower right third molar, pain on swallowing, bad taste and restricted mouth opening. The medical officer recorded acute pericoronitis of the lower right third molar, with a swollen, ulcerated operculum indented by the upper third molar, pus on pressure, trismus with mouth opening of 25 mm, tender right submandibular lymph nodes and a temperature of 38.1 degrees. The operculum was irrigated and chlorhexidine rinses, amoxicillin and metronidazole were prescribed. No dental officer was available on the base and the next scheduled dental visit was in late March. "acute pericoronitis 48, trismus 25 mm"
- 18 Mar 2018 — After an initial improvement, the pain, swelling and trismus returned and increased while he continued force protection duties. He re-presented with swelling of the right lower face and submandibular region, mouth opening of 12 mm, difficulty swallowing and a temperature of 38.9 degrees. A pericoronal abscess with spreading submandibular infection was diagnosed, and he was aeromedically evacuated to a role 3 facility. "pericoronal abscess, trismus 12 mm"
- 20 Mar 2018 — CT of the neck on 19 March 2018 confirmed a collection extending from the lower right third molar region into the right submandibular and pterygomandibular spaces. An oral and maxillofacial surgeon performed incision and drainage and extraction of the lower right and upper right third molars under general anaesthesia. He received intravenous antibiotics for four days and returned to duty after three weeks. "I and D, extraction 48 and 18"
- 05 Apr 2018 — At post-operative review at the role 3 facility the surgeon recorded healing extraction sockets and resolution of the submandibular infection, but persisting numbness of the right lower lip and chin from irritation of the inferior alveolar nerve, and right jaw joint clicking and pain after the prolonged trismus. He was returned to duty in Iraq with jaw exercises and review on return to Australia. "right lip numbness, TMJ clicking"
Symptoms
At onset the veteran had pain and swelling of the gum flap over the lower right third molar, pain radiating to the ear, pain on swallowing, a foul taste, halitosis, restricted mouth opening and fever, with tender lymph nodes under the right jaw. At the worsening he had right facial and submandibular swelling, severe trismus, difficulty swallowing and high fever.
He now reports occasional aching and numbness along the right lower lip and chin, attributed to the surgery, intermittent clicking and discomfort of the right jaw joint since the severe trismus, and anxiety about dental treatment.
Imaging
- 14 Aug 2017 — Orthopantomogram: "Partially erupted, mesioangularly impacted lower right third molar with a distal pericoronal radiolucency. Supra-erupted upper right third molar. Other third molars unerupted and asymptomatic."
- 19 Mar 2018 — CT neck with contrast: "Rim-enhancing collection around the crown of the lower right third molar extending into the right submandibular and pterygomandibular spaces, with surrounding cellulitis. Airway patent."
Onset Date
The most likely date of onset of this condition is 24 Feb 2018.
At that date the veteran was on warlike service at a partner force training base in Iraq, the day after returning from a seven-day field activity during which he could not brush his teeth, three weeks after a rocket attack on the base and eight days after completing a course of prednisolone. He was smoking about 20 cigarettes a day and sleeping three to four hours a night.
This date is appropriate because his role 1 visit on 12 February 2018 for tonsillitis recorded a normal oral examination apart from the known partially erupted tooth, with no gum swelling, and at his first presentation on 25 February 2018 he dated the pain and swelling to 24 February 2018.
For the 2-week infection factor, the 2 weeks before onset run from 10 Feb 2018 to 24 Feb 2018; the tonsillitis of 12 February 2018 falls within it. For the 1-month factors, the 1 month before onset runs from 24 Jan 2018 to 24 Feb 2018; the rocket attack of 05 February 2018 and the prednisolone of 12 to 16 February 2018 fall within it. For the 7-day factors, the 7 days before onset run from 17 Feb 2018 to 24 Feb 2018, during which he had no oral hygiene and slept less than five hours a night. For the smoking factor, the 6 months before onset run from 24 Aug 2017 to 24 Feb 2018, throughout which he smoked at least 15 cigarettes a day. The partially erupted lower right third molar and the opposing supra-erupted upper third molar were present at onset, and he was aged 22.
For the worsening factors, the period after onset runs from 24 Feb 2018 to the documented worsening on 18 Mar 2018, during which the opposing tooth continued to traumatise the flap, he continued to smoke and the recommended extraction could not be obtained.
1. What is the formal diagnosis of the condition claimed above?
The formal diagnosis is Pericoronitis (ICD-10-AM K05.2, acute periodontitis including acute pericoronitis) of the lower right third molar. No Statement of Principles has been determined for this condition.
Pericoronitis is inflammation and infection of the soft tissue (operculum) surrounding the crown of a partially erupted tooth, most often a lower third molar. Food and bacteria trapped beneath the flap cause a mixed anaerobic infection, producing pain, swelling, trismus, a foul taste and fever. Trauma to the flap from the opposing tooth, poor oral hygiene, smoking, stress, fatigue, recent respiratory infection and reduced immune function are recognised precipitants. Untreated it can progress to a pericoronal abscess and spread into the fascial spaces of the neck, and recurrence is prevented by removal of the tooth.
The condition began on 24 February 2018 on warlike service in Iraq and worsened to a pericoronal abscess with spreading submandibular infection on 18 March 2018, treated by incision and drainage and extraction on 20 March 2018.
2. For each diagnosis identified, please also provide the following dates:
When did the veteran first experience symptoms attributable to this condition?
24 February 2018.
When did the veteran first present to a health / medical provider for this condition?
25 February 2018.
When was the condition confirmed / formally diagnosed?
25 February 2018.
When did the veteran first present to you (or your practice) for this condition?
09 September 2025.
3. How was this diagnosis confirmed? i.e. what were the key symptoms and signs, investigation results, specialist opinions?
The diagnosis was made clinically by the role 1 medical officer on 25 February 2018, who recorded a swollen, ulcerated operculum over the partially erupted lower right third molar, indented by the opposing upper third molar, with pus on pressure, trismus, regional lymphadenopathy and fever. The pre-deployment orthopantomogram of 14 August 2017 confirmed the partially erupted, mesioangularly impacted tooth with a pericoronal space.
The worsening was confirmed clinically on 18 March 2018 and by CT on 19 March 2018, which showed a collection extending into the submandibular and pterygomandibular spaces. An oral and maxillofacial surgeon confirmed the diagnosis at surgery on 20 March 2018.
4. What do you consider to be the cause(s) of the condition in this veteran? Give consideration to constitutional and common risk factors, pre-existing injuries or diseases, and occupational or lifestyle risks, as well as direct causative mechanisms.
No Statement of Principles has been determined for pericoronitis, so the claim is decided on the sound medical-scientific evidence of what causes the condition, without the limits of a Statement of Principles. The recognised causes below are drawn from the dental and medical literature, including studies of pericoronitis in military personnel during training and operations, and each is addressed as it applies to the veteran.
Legislation: the clinical onset of this condition was on 24 February 2018, after 1 July 2004, during continuous full-time service. This is a Military Rehabilitation and Compensation Act 2004 (MRCA) claim. The reasonable hypothesis standard applies to the veteran's warlike service in Iraq, where the condition began and worsened, and the balance of probabilities standard applies to peacetime service, including the pre-deployment period when extraction was recommended but not performed. Each cause must be related to the person's service. Under the beneficial approach required by the legislation, the absence of documentation does not mean that an event or exposure did not occur: lack of evidence is not evidence of lack.
Recognised causes on the medical-scientific evidence (no Statement of Principles)
Causative factors
Cause 1: having a partially erupted or impacted tooth with an overlying operculum in the affected region at the time of the clinical onset of pericoronitis; — MET
- The pre-deployment dental examination and orthopantomogram of 14 August 2017 recorded a partially erupted, mesioangularly impacted lower right third molar with a posterior operculum and food trapping, and the dental officer recommended removal before deployment. The surgery could not be scheduled before the veteran deployed, and the tooth was still present with its operculum at onset on 24 February 2018 on warlike service.
Cause 2: having trauma to the operculum from an opposing tooth at the time of the clinical onset of pericoronitis; — MET
- The supra-erupted upper right third molar bit directly onto the operculum of the lower right third molar, recorded on 14 August 2017 and again on 25 February 2018, when the medical officer noted the flap indented and ulcerated by the upper tooth. This repeated trauma was present at onset.
Cause 3: being unable to maintain oral hygiene for at least the 7 days before the clinical onset of pericoronitis; — MET
- From 16 to 23 February 2018 the veteran accompanied the partner force on a field activity in Iraq with severe water restrictions, his toiletries were lost, and he could not brush his teeth or rinse for seven days. This covered the 7 days before onset on 24 February 2018, and plaque and food debris accumulated under the operculum.
Cause 4: having an upper respiratory tract infection or tonsillitis within the 2 weeks before the clinical onset of pericoronitis; — MET
- On 12 February 2018, 12 days before onset, the role 1 facility diagnosed exudative tonsillitis with fever, contracted in shared accommodation on warlike service. This falls within the 2 weeks before onset, from 10 to 24 February 2018. Recent respiratory infection is a recognised precipitant of pericoronitis.
Cause 5: experiencing severe psychological stress within the 1 month before the clinical onset of pericoronitis; — MET
- On 05 February 2018, 19 days before onset, a rocket impacted about 60 metres from the veteran's force protection position and he sheltered in a bunker for four hours. He described ongoing fear of further attacks through February. This severe stress on warlike service fell within the 1 month before onset, and stress reduces local immune defences and is associated with pericoronitis in military populations.
Cause 6: being sleep deprived, with less than 5 hours of sleep per night, for at least the 7 days before the clinical onset of pericoronitis; — MET
- Through February 2018 the veteran slept three to four hours a night between force protection shifts and during the partner force field activity, recorded at his role 1 visits. This covered the 7 days before onset, from 17 to 24 February 2018, and was imposed by his duties on warlike service.
Cause 7: smoking at least 10 cigarettes per day for at least the 6 months before the clinical onset of pericoronitis; — MET
- The veteran began smoking during field training in 2014 and smoked about 15 cigarettes a day, recorded on 14 August 2017, increasing to about 20 a day on deployment. This covered the 6 months before onset, from 24 August 2017 to 24 February 2018. Smoking impairs gingival blood flow and immune response and is a recognised risk factor for pericoronitis.
Cause 8: taking a systemic corticosteroid or another drug that impairs immune function within the 1 month before the clinical onset of pericoronitis; — MET
- The veteran took prednisolone 50 mg daily from 12 to 16 February 2018 for a dust-related exacerbation of asthma on warlike service, within the 1 month before onset. High-dose corticosteroids suppress local immune responses to the anaerobic bacteria beneath the operculum.
Cause 9: being aged from 16 to 30 years at the time of the clinical onset of pericoronitis; — MET
- The veteran was born on 19 July 1995 and was 22 years old at onset on 24 February 2018. Pericoronitis is most common between 16 and 30 years, the period of lower third molar eruption, and young soldiers are over-represented in dental emergencies on deployment.
Worsening factors
Worsening 1: having continued trauma to the operculum from an opposing tooth after the clinical onset and before the clinical worsening of pericoronitis; — MET
- The supra-erupted upper right third molar was not removed or adjusted after onset because no dental officer was available, and it continued to traumatise the swollen operculum with every bite from 24 February to 18 March 2018, as recorded at both presentations.
Worsening 2: having delayed removal of the causative tooth after the clinical onset of pericoronitis, before the clinical worsening of pericoronitis; — MET
- Removal of the lower right third molar was recommended on 14 August 2017 and again indicated at onset on 25 February 2018, but no dental officer or oral surgeon was available on the base, and the next scheduled dental visit was in late March 2018. The tooth was not removed until 20 March 2018, after the infection had spread on 18 March 2018.
Worsening 3: smoking at least 10 cigarettes per day, or being unable to maintain oral hygiene, after the clinical onset and before the clinical worsening of pericoronitis; — MET
- The veteran continued to smoke about 20 cigarettes a day between onset and the worsening on 18 March 2018, and continuing water restrictions and dust storms limited his ability to carry out the prescribed chlorhexidine rinses and warm saline irrigation while he remained on force protection duties.
Worsening 4: inability to obtain appropriate clinical management for pericoronitis. — MET
- On warlike service the veteran had no access to a dental officer or oral surgeon after onset, and the definitive treatment, removal of the offending teeth, was unavailable until he was evacuated after the infection had spread to the submandibular and pterygomandibular spaces. Under Brew v Repatriation Commission (1999) this is an inability to obtain appropriate clinical management.
The % contribution of the causes is 100% and significant.
Sequelae
The spreading infection and its surgical treatment have left intermittent numbness of the right lower lip and chin from irritation of the inferior alveolar nerve, and right temporomandibular joint discomfort and clicking that began with the severe trismus. These are sequelae of the pericoronitis and its treatment.
Unintended Consequence
Met. The prednisolone 50 mg daily prescribed at the role 1 facility from 12 to 16 February 2018 for a dust-related asthma exacerbation suppressed local immune defences shortly before onset, and the extraction of 20 March 2018 caused the inferior alveolar nerve symptoms. These are unintended consequences of treatment provided by the Commonwealth during his service (the MRCA provisions on treatment-related conditions).
Inability to Attain Appropriate Medical Management
MET. Removal of the partially erupted lower right third molar was recommended before deployment on 14 August 2017 but could not be scheduled, and the veteran was deployed with a waiver. After onset on warlike service there was no dental officer or oral surgeon on the base, the next dental visit was a month away, and he remained on force protection duties with antibiotics and rinses only. The infection spread to the fascial spaces of the neck by 18 March 2018 and required aeromedical evacuation, incision and drainage and extraction. Applying the objective and subjective tests in Brew v Repatriation Commission (Full Federal Court, 10 September 1999, Merkel J), the unavailability of definitive dental treatment before and during deployment amounts to an inability to obtain appropriate clinical management, and this contributed to the worsening.
5. Please provide a Health Summary and a medication / prescribing history.
See attached report.
References
- 04 Feb 2013, Entry dental examination, Army dental officer
- 14 Aug 2017, Pre-deployment dental examination and orthopantomogram, Dental officer
- 05 Feb 2018, Incident report, rocket attack, partner force training base, Iraq
- 12 Feb 2018, Role 1 treatment record, Medical officer, Iraq
- 25 Feb 2018, Role 1 treatment record, Medical officer, Iraq
- 18 Mar 2018, Role 1 treatment record and aeromedical evacuation request, Medical officer, Iraq
- 19 Mar 2018, CT neck with contrast, Radiologist, Role 3 facility
- 20 Mar 2018, Operation report, Oral and maxillofacial surgeon
