Bashar AKM, Akter K, Chaudhary GK, Rahman A Primary molar with chronic periapical abscess showing atypical presentation of simultaneous extraoral and intraoral sinus tract with multiple stomata. BMJ Case Rep. 2019; 12 https://doi.org/10.1136/bcr-2018-229039
Swales KL, Rudralingam M, Gandhi S Extraoral cutaneous sinus tracts of dental origin in the paediatric patient. A report of three cases and a review of the literature. Int. 2016; 26:391-400 https://doi.org/10.1111/ipd.12205
Azizlou E, Sobhani MA, Ghabraei S, Khoshkhounejad M, Ghorbanzadeh A, Tahan SS Extraoral sinus tracts of odontogenic origin: a case series. Front Dent. 2020; 17 https://doi.org/10.18502/fid.v17i29.4750
Sammut S, Malden N, Lopes V Facial cutaneous sinuses of dental origin – a diagnostic challenge. Br Dent J. 2013; 215:555-558 https://doi.org/10.1038/sj.bdj.2013.1141
Diller G-P, Lammers AE, Fischer A Immunodeficiency is prevalent in congenital heart disease and associated with increased risk of emergency admissions and death. Eur Heart J. 2023; 44:3250-3260 https://doi.org/10.1093/eurheartj/ehad029
Levine RS Childhood caries and hospital admissions in England: a reflection on preventive strategies. Br Dent J. 2021; 230:611-616 https://doi.org/10.1038/s41415-021-2945-8
Chronic extra-oral cutaneous sinus infection in a child: case report Laura CU Ota Sara Chapman Mina Vaidyanathan Bethan Thomas Martin Woods Marielle Kabban Dental Update 2025 52:3, 182-184.
An extra-oral sinus is often assumed to be of non-odontogenic pathology and is rarely seen in paediatric patients, so inappropriate management often results. This case report highlights factors surrounding the diagnosis and treatment of extra-oral cutaneous sinus tracts as a manifestation of intra-oral pathology. Because this condition is rare, it is often misdiagnosed, which can result in inappropriate referrals (e.g. to dermatology teams, overtreatment with surgery or treatment with antibiotics), leading to recurrence. These patients should be referred to a specialist in paediatric dentistry for management. The importance of rigorous clinical investigation, appropriate referral and interdisciplinary management in paediatric patients is illustrated. In this case, elimination of dental infection led to complete resolution.
CPD/Clinical Relevance: Dental practitioners should consider infection of odontogenic origin as a differential diagnosis when a child presents with an extra-oral draining cutaneous sinus tract.
Article
A cutaneous sinus tract of odontogenic origin in the head and neck is rare in paediatric patients.1 An extra-oral sinus can be assumed to be of non-odontogenic pathology. However, it can be a sequel of a chronic infection owing to caries, trauma or periodontal disease.2 The resulting cytokine production and chronic inflammatory cell infiltration can lead to an exudate that drains via a sinus tract lined by epithelium or granulation tissue.3 A chronic peri-apical abscess is the main cause of odontogenic extra-oral cutaneous sinus tracts.4 This chronic inflammatory disorder of peri-radicular tissues is a sequela of pulpal necrosis, which leads to bacterial invasion of the surrounding periodontal ligament and bone. The resulting host-driven immune response to pathogens and inflammatory processes leads to alveolar bone resorption. This process continues until the cortex of bone and periosteum are breached. Then, depending on factors such as gravity, the virulence of the micro-organisms and anatomy of fascial spaces and musculature, either an intra-oral or extra-oral cutaneous sinus tract forms.4 The path of least resistance, through which infection travels, tends to be through alveolar bone draining intra-orally. The majority (80–87%) of extra-oral sinus tracts result from chronic infection related to mandibular teeth.5 The position of the root apex of a tooth relative to muscular attachments can also impact the route of drainage. In the mandible, when the infection destroys the outer cortical plate, if the suppurative exudate tracks below the level of the mentalis, mylohyoid or buccinator muscle attachments, it will form an extra-oral sinus.
In theory, children should present with more extra-oral sinuses owing to their undeveloped alveolar processes, partially erupted teeth and immature roots with open apices.2 However, most available case reports of odontogenic cutaneous sinus tracts concern adults.6 Extra-oral sinus tracts may present as an erythematous nodule with crusting and/or purulent discharge, commonly on the chin, cheek, submandibular area or more rarely, nasal floor.5 The diagnostic challenge arises from the distant location of the underlying dental source of infection, especially as dental symptoms may present in only 50% of patients.6 In the literature, there are reports of misdiagnosis resulting in biopsies, a worsening of the chronic nature of the lesion and aesthetics being compromised by scarring.2 While the virulence of bacteria impacts the likelihood of sinus tract presentation, host resistance factors will also play a significant role. Those who are immunocompromised frequently present with more complications than healthy patients.2 Patients with congenital heart disease commonly have reduced immunocompetence and an increased risk of morbidity and mortality.7 Paediatric cardiac disease affects more than 15 million children orldwide.8
Figure 1. OPG confirming gross caries in the crown of the LL6 and showing peri-apical radiolucencies associated with both the mesial and distal roots of the LL6. Additionally, there were caries in the URE, ULD, ULE, LRD, LRE and LR6.Figure 2. The pre-operative appearance of the extra-oral cutaneous sinus tract with the crusting, erythema and raised nodular appearance.
Case report
An 8-year-old female patient presented to a children's dental emergency clinic with a 2-month history of a firm 2-cm swelling in the left submandibular region. The patient had previously seen her general dental practitioner who had attempted endodontic therapy on a lower molar tooth; however, a facial swelling subsequently appeared. Two courses of antibiotics had been prescribed by the general medical practitioner and general dental practitioner.
The patient's medical history revealed she had mild aortic root dilatation and regurgitation. She had also been treated for an infantile haemangioma on the central neck area with propranolol. There was a family history of hereditary haemorrhagic telangiectasia and she was under investigation for Marfan syndrome.
Figure 3. Ultrasound demonstrating a discharging sinus in the left submandibular triangle that overlayed an area that tracked from the lingual aspect of the mandible and therefore was most likely associated with the carious LL6. (a) Outer surface of the skin; (b) hypoechoic foci with internal debris, corresponding to sinus; (c) adjacent soft tissueFigure 4. Extracted lower left first molar with a peri-apical granuloma
Upon extra-oral examination, the submandibular swelling was firm yet mobile, tender on palpation with a surrounding erythematous outline and with blanching on application of pressure. Intra-orally, there was no swelling or tenderness of the buccal sulcus. There was a grossly carious lower left first molar (LL6), which on OPG had peri-apical radiolucencies associated with the mesial and distal roots. The contralateral lower right first molar also had occlusal caries and she had five carious primary teeth as well.
The patient was referred for an ultrasound scan, which revealed a fistula extending from the body surface to the mandible.
Management
The successful dental treatment of paediatric patients with congenital heart disease requires careful multidisciplinary management by the patient's dental and cardiology teams, as well as the preassessment team.
The patient was referred to the joint orthodontic and paediatric dentistry multidisciplinary clinic. Owing to the poor prognosis of the lower first permanent molars, and in line with the guidance by the Faculty of Dental Surgery at the Royal College of Surgeons of England, extractions under general anaesthetic were planned of the five carious primary dentition and all first permanent molars.9
The case was also discussed with the paediatric oral and maxillofacial surgeon, who advised against any soft tissue surgery at the time of tooth extraction and against the prescription of post-operative antibiotics. The child was reviewed by the paediatric oral and maxillofacial surgeon 2 months after surgery, when healing of intra-oral sockets and improvements in the extra-oral sinus were observed, with no obvious draining sinus, punctum or cervical lymphadenopathy.
The child was to be reviewed at 12 months to allow the left submandibular region to mature before any scar revision was considered.
Discussion
Misdiagnosis and mismanagement of extra-oral cutaneous sinus tracts of dental origin have been reported in the literature.
A reason for misdiagnosis is that the extra-oral subcutaneous sinus can mimic the appearance of infected sebaceous, epidermoid or thyroglossal cysts, a furuncle, a congenital fistula, a foreign body reaction, a granulomatous disorder, pyogenic granuloma, a salivary gland fistula, a deep mycotic infection or a basal or squamous cell carcinoma.1,2
This may lead to a child receiving unnecessary invasive investigations and overtreatment, including surgical excision, biopsy, radiotherapy and repeated unnecessary provision of topical and systemic antibiotics.2 This excessive treatment can evoke anxiety surrounding treatment in the child and impact the family with regards to fear of the lesion being sinister.
To minimize misdiagnosis, physicians, dermatologists and dentists should consider an odontogenic origin for a patient presenting with an extra-oral cutaneous sinus tract. Special investigation with sensibility testing and dental radiography should be performed.
The aetiology for the cutaneous extra-oral sinus tract in this patient was a grossly carious tooth with a necrotic pulp. Treatment planning for these teeth in children relies on a range of factors, such as medical and social history as well as clinical and radiographic findings, including the development of the dentition and orthodontic considerations.
In a previous case series of three paediatric patients presenting with externally draining cutaneous sinus tracts that were initially misdiagnosed, the correct diagnoses were made only following referral to a specialist paediatric dental clinic.2 Therefore, dental and medical colleagues should refer these patients to a specialist paediatric dental department for appropriate management.
Concomitantly, if the general dental practitioner is able to make a definitive diagnoses, ideally they should start initial management to eliminate or decontaminate the source of infection via extraction or extirpation, where co-operation and compliance allows.
If a dentist has enhanced skills, such as an accredited inhalation sedation qualification, this can be employed to provide an anxiolytic effect, improving co-operation.
Conclusion
Chronic peri-apical abscesses are the main cause of odontogenic extra-oral cutaneous sinus tracts, which are a result of pulpal necrosis.4 Pulpal necrosis is caused by caries, which is the most common cause of hospital admission among children aged 5–9 years.10 When abscesses are left neglected and chronic infection persists, the risk of the diagnostic dilemma of an extra-oral cutaneous sinus tract is heightened.
Efficient diagnosis is a prerequisite for the successful management of patients presenting with an extra-oral cutaneous sinus tract and it is essential clinicians consider an odontogenic aetiology in their differential diagnoses.
Misdiagnosis leads to mismanagement and a child may undergo multiple inappropriate surgical treatments. Investigations should involve sensibility testing and dental radiography. A prompt diagnosis should be followed by referral to the appropriate specialist paediatric dental team for management, with initial management (e.g. pulp extirpation/extraction) starting concurrently in primary care by the general dental practitioner.
