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Facial infections - an overview |
PRACTICAL TIPS
Good oral examination requires:
- Bright light leaving both hands free - torch is unsatisfactory and fixed lights need too much adjustment. A head lamp such as a Petzel ($60-80) or preferably a simple halogen head lamp with transformer (about $400) is invaluable and may be used for multiple other uses and is also portable.
- Two tongue depressors or preferably two dental mirrors - these can be used to examine inaccessible spots, retract the cheeks and depress the tongue. The metalic handle is ideal for percussing teeth for tenderness.
- A square of gauze to dry oral secretions and check patency of salivary ducts. Also allows good grip on the tongue to inspect posterior 2/3 and the lateral
- border.
- A dental syringe with 27G long needles together with 2% Xylocaine with1: 80000 adrenaline - good for oral LA prior to aspiration, drainage etc. (very useful for other suture jobs - but remember high adrenaline concentration.)
Introduction
Facial infections are a relatively common presentation to both general medical and dental practice. Most originate in superficial structures (skin, subcutanous tissue etc.) and are often easily diagnosed and treated.
Infections originating in deeper structures can be severe, rapidly progressive and may cause prolonged morbidity, long term complications as well as potentially endanger life. Efficient treatment requires accurate diagnosis, early aggressive medical treatment and in most cases urgent decisive surgical management.
Severe buccal space infection
Complex and severe cases may require multidisciplinary approach including the GP, dental surgeon, radiologist, oral and maxillo-facial surgeon, ENT surgeon, a skilled anaesthetist as well as occasionally the infectious diseases specialist and possibly the intensivist. Ophthalmology and rarely neurosurgery may also be needed.
Submandibular space infection with external drains in situ
Ludwig's angina - bilateral submandibular/sublingual space infection
Good nursing, speech pathology as well as a dietician can speed up the recovery phase.
Presentation
The patient presents with a swollen face and occasionally swollen neck. Toothache or facial pain may or may not be a feature. There is often general malaise and possibly rigors with fever. Patients may complain of trismus (inability to open the mouth fully), pain or difficulty in swallowing, drooling, sore throat and a hoarse voice.
History
One should document the usual historical features of the current complaint with additional attention to:
- Increased pain and swelling on exposure to food (salivary gland obstruction?).
- Recent dental treatment, especially root canal treatment and extractions.
- Any trauma to the face or teeth (either bony fractures or devitalized teeth).
- Recent oral surgery (surgical removal of wisdom teeth, cysts etc.).
- Past facial fractures fixation (infected plates, wires, etc?).
- Past salivary gland surgery.
- History of head and neck cancer with possible radiotherapy to the region (possible osteoradionecrosis of the jaw bones?).
- Upper respiratory tract viral infections, nasal discharge, etc.
Examination
Specific attention should be paid to the location of swelling, size, flactuance, any possible pointing and coexistent lymph node enlargement.
Good oral examination should include:
- presence of halitosis,
- evidence of intraoral pus draining and where, any tongue elevation, any sublingual or submandibular swelling,
- swelling in the mandibular or maxillary sulci,
- palatal swelling especially of the soft palate or uvula,
- general dental state, patency of salivary outlets (parotid, submandibular and sublingual),
- nature of saliva produced (clear, thick, pus?).
Suspect teeth should be tapped with a metallic object to elicit any tenderness to percussion.
Swelling should be palpated bimanually if possible with a finger of one hand intraorally and and the second hand extraorally (pushing towards the oral site). The neck should be evaluated for swelling, lymphadenopathy and possible tracheal deviation.
Aetiology of major facial infections
Most originate in the jaws, teeth, surrounding periodontal soft tissues as well as the paranasal sinuses and the major salivary glands.
Teeth can contribute by:
(1) Decay (caries) reaching the dental pulp=pulpitis, this in turn spreads to supporting bone resulting in (2) periapical abscess which in turn may spread subperiosteally.
(2) Periapical abscess may occur in seemingly intact but devitalised teeth (trauma, cracks or decay under fillings).
(3) Periapical and periodontal abscess may form as a result of chronic gingivitis and supporting bone and soft tissue loss (periodontal disease) - note again the tooth may be entirely intact clinically and radiographically.
(4) Erupting teeth (especially partially impacted lower third molars) can result in inflammation and infection of the gum flap preventing eruption (operculum) with swelling pus etc. around the crown (pericoronitis).
(5) Retained roots supragingival or subgingival.
The jaws:
(1) Can develop cysts or tumours that can range from odontogenic (=dental origin) to either primary or secondary malignancy. Most are derived from the dental apparatus and although benign can nevertheless continuously grow and become secondarily infected on breaching the surrounding bone.
(2) Osteomyelitis although rare can be the result of chronic infection as mentioned before.
(3) Osteoradionecrosis occurs readily in irradiated jaws subjected to further trauma (such as extractions).
(4) Rarer are tuberculosis, Actinomycosis and syphilitic osteomyelitis.
(5) Most jaw fractures in the tooth bearing segments are by definition compound to the oral cavity and can easily be infected by the oral microbes.
(6) Extraction sites again are comparable to compound fractures and it is surprising that infection is so relatively rare.
Major salivary glands:
(1) May be the subject of either viral or bacterial infections often superimposed on obstruction of ducts (stone, stricture, etc).
(2) Tumours rarely also become secondarily infected.
Paranasal sinuses
(1) May be primarily infected, obstruct and result in facial swelling.
(2) May become infected secondary to infected teeth protruding into the maxillary sinus (upper premolar and molar teeth often do).
(3) Tumours or cysts may become infected.
(4) Fractures such as the orbital floor are by definition compound to the “outside” and may result in orbital cellulitis.
Microbiology
Facial infections tend to be polymicrobial with a predominance of anaerobic organisms. In severe cases Gram-ve organism tend to be involved as well.
Investigations
In many cases careful history and examination will make diagnosis clear, however certain investigation will still be necessary.
Plain X rays:
(1) The OPG (orthopantomogram) is invaluable in displaying the teeth, whole of mandible, tooth bearing segment of the maxilla as well as parts of the maxillary sinuses. Use for any suspected fractures of the mandible, periapical abscesses and bony cysts and tumours. Will show impacted third molars ('wisdom teeth').
(2) Occipito-mental 15 and 30 degrees (“Water’s view”) will show both maxillary sinuses (effusion?), orbital floor and most fractures of the maxilla.
(3) Mandibular occlusal views and lateral oblique views may demonstrate stones in the submandibular gland.
(4) 'Puffed cheek' view may demonstrate stones in the parotid duct.
Sialography:
Can be used for suspected gland obstruction however CT sialogram is the gold standard.
Ultrasound:
Useful in confirming collections as well as a guide to aspiration. Will also show stones in salivary ducts and glands.
CT scan:
With axial and coronal views will demonstrate exact extent of the swelling, potential airway compromise and is invaluable to both the surgeon and anaesthetist. However patients unwell enough to potentially obstruct their airway should be taken straight to theatre rather than risk an emergency in the radiology dept.
Microbiology of any pus or discharge.
The usual blood tests.
Spread of infections
Bony infection tends to perforate the cortical plates along path of least resistance. Subsequent subperiosteal spread tends to be directed by muscle and facial attachments. Thus infections of mandibular molar teeth for example tend to spread to the submandibular space.
A number of potential tissue spaces exist, the most important being: buccal space, sublingual space, submandibular space, parapharyngeal space and retropharyngeal space. Spread can occur throughout these with airway compression once the parapharyngeal and retropharyngeal spaces are filled.
Orbital floor can be perforated by pus from the sinus resulting in subperiosteal abscess or even orbital abscess. Preseptal cellulitis may result from buccal space infections and may progress to orbital cellulitis.
Lymphatic spread to the deep cervical lymphatics occurs commonly.
Occasionally haematogenous spread may result in bacteraemia, distant septic foci and cavernous sinus thrombosis.
Treatment
Antibiotics alone will not cure most deep facial infections.
Most infections have a distinct cause and only surgical treatment (removal of the cause and drainage of accumulated pus) will prevent worsening and recurrence.
In early cases the surgical treatment may be as simple as root canal treatment of the tooth suspected or alternatively simple tooth extraction by the patient’s dentist followed by oral antibiotics.
More advanced cases need urgent admission for intravenous antibiotics followed by urgent surgery to remove the cause as well as achieve incision and drainage of tissue spaces involved.
These cases may need expert fiberoptic endotracheal intubation with prolonged (few days) intubation and occasionally emergency surgical airway access such as cricothyrotomy or tracheostomy may be needed.
These cases will need ICU postoperatively until the safety of airway is assured.
Surgically most cases can be approached transorally. Removal of the cause (tooth, stone, etc) is followed by incision and drainage and drain insertion. One should avoid the temptation to cut through facial skin for reasons of facial nerve preservation as well as to avoid the ugly puckered scar that invariably results.
Submandibular and sublingual spaces full of pus need to be drained trancutanously via neck incisions with drains insertion. The patient should be on triple IV antibiotics covering aerobic Strep species as well as anaerobes as well as Gram-ve organisms. Eg: Amoxycillin 1g tds-qid+Metronidazole 500mg tds+Gentamicin 5mg/kg/day in single dose.
Early diagnosis, prompt antibiotic treatment (Amoxy-cillin and Flagyl), together with early removal of the cause should prevent most complications and result in early recovery.
Arthur Bilski is an oral and maxillo-facial surgeon with rooms in St Vincent’s Hospital, Lismore, NSW, Australia.
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