Ludwig's angina is a polymicrobial cellulitis of the submandibular, submental, and sublingual spaces — it arises almost exclusively from an infected lower second or third molar tooth. The infection spreads along fascial planes and does not spontaneously drain. The raised tongue and floor-of-mouth swelling can displace the tongue posteriorly, directly obstructing the oropharynx — progression is variable and can be rapid. It is one of the true dental emergencies that GPs must recognise. The clinical features are pathognomonic: bilateral submandibular swelling that is brawny (indurated), tender, and "woody" in texture (not fluctuant — it is cellulitis not abscess), elevation of the tongue, trismus, drooling, and a characteristic "bull neck" appearance. Any trismus combined with floor-of-mouth swelling in the context of recent dental pain = Ludwig's angina until proven otherwise = 999 — do not attempt extensive oral examination if airway compromise is suspected. Suspected SVC obstruction needs same-day hospital assessment (acute oncology / A&E) — corticosteroids, anticoagulation, stenting and oncological treatment depend on severity, thrombosis, malignancy and tissue diagnosis, and are directed by the hospital team; do not give a GP "bridge" dose of dexamethasone unless it is part of a local oncology/emergency protocol. GPs should be familiar with Pemberton's sign: raising both arms above the head causes worsening facial plethora and sometimes syncope due to further narrowing of the thoracic inlet by the raised arms — it supports thoracic inlet/SVC obstruction.

The parotid gland is one of the most anatomically specific structures in facial swelling — it lies anterior to and below the ear, and swelling of the parotid pushes the earlobe outward (a characteristic sign). Stensen's duct opens at the parotid papilla opposite the upper second molar tooth — purulent discharge from this opening confirms acute suppurative parotitis. The most important clinical distinction for a parotid mass is between inflammatory (warm, tender, associated with systemic upset, bilateral in viral parotitis) and neoplastic (firm, slow-growing, painless, unilateral). The "deep lobe" of the parotid projects medially through the stylomandibular tunnel — deep lobe parotid tumours can present as a pharyngeal mass (visible medially in the throat as a "dumbbell tumour") without obvious external swelling. Increasing swelling with meals (mealtime syndrome) is pathognomonic of salivary duct obstruction by a calculus (sialolithiasis) — the diagnostic mechanism is that eating triggers salivary flow, which cannot drain past the stone, causing acute distension of the duct and gland.

The distinction between allergic angio-oedema (IgE-mediated) and bradykinin-mediated angio-oedema (ACEi-induced or hereditary C1-inhibitor deficiency) is critically important because the treatments are completely different — and standard allergic treatments (antihistamines, corticosteroids) are ineffective for bradykinin-mediated angio-oedema. Allergic angio-oedema: rapid onset with allergen exposure, associated urticaria, responds to adrenaline + antihistamine + corticosteroid. ACEi-induced: can occur any time during ACEi treatment (even years in), predominantly affects lips and tongue (not urticaria), does NOT respond to antihistamines, resolves with ACEi cessation; specialist/hospital teams may use icatibant (bradykinin receptor antagonist) or C1-inhibitor concentrate. Hereditary angio-oedema (HAE — autosomal dominant C1-INH deficiency): no urticaria, triggers include stress/trauma/oestrogens/dental work, abdominal pain attacks (visceral angio-oedema), family history. C4 may be low during an attack but normal between attacks — interpretation requires specialist context, so complement testing should be arranged through an allergy/immunology pathway. Mumps notification: suspected mumps is a statutory notifiable disease — notify the local Health Protection Team (HPT) and arrange testing (e.g. saliva/buccal swab) following the current health-protection pathway. Check MMR vaccination status — the primary vaccine series is 2 doses. Offer MMR catch-up to unvaccinated people — this protects against future susceptibility but is not post-exposure treatment for the current episode.

Bimanual palpation of the floor of mouth is the essential examination for detecting submandibular salivary stones — one gloved finger is placed inside the mouth along the floor, and the other hand palpates from externally under the jaw. A stone in Wharton's duct is felt as a hard, non-tender mobile nodule along the duct. Ultrasound is widely available and an appropriate first-line imaging test when the diagnosis is uncertain or symptoms persist; CT is a specialist option. Stensen's duct (parotid) stones are harder to palpate but can be felt at the duct orifice. The OPG (orthopantomogram — panoramic dental X-ray) is the key dental investigation — it shows all teeth, periapical pathology, mandible, maxilla, and can identify salivary calculi. It is arranged and interpreted by dental practices or oral surgery departments — it is not a substitute for dental assessment and is not a routine GP investigation. In adults with unexplained unilateral salivary gland swelling, FNA (fine needle aspiration) cytology of the gland is the key investigation for distinguishing inflammatory from neoplastic causes — arranged by oral and maxillofacial surgery (OMFS) or radiology.

The head and neck suspected cancer pathway has a particularly important role in facial swelling — head and neck cancers often present with a painless facial or neck mass. In the UK, NICE NG12 (updated April 2026) recommends a suspected cancer pathway referral for a persistent unexplained lump in the neck (oral cancer criterion, any age; laryngeal criterion aged 45 and over, especially in people who smoke or drink alcohol); NICE does not set a universal age or duration threshold for unilateral facial swelling — persistent or progressive unexplained unilateral facial, parotid, submandibular or cervical swelling, or unexplained cranial nerve palsy, should go through an urgent local head-and-neck pathway based on clinical concern where NICE criteria are not met. Facial cancer (parotid malignancy, SCC of skin, mucosal SCC) often presents as a gradually growing painless facial mass — the painlessness misleads patients and GPs into watchful waiting rather than urgent referral. Key clinical features that raise malignancy concern in facial swelling: non-tender, progressive, firm or hard consistency, skin fixation or ulceration, cranial nerve deficit (facial nerve palsy in parotid cancer = malignant until proven otherwise — facial nerve runs through the parotid), supraclavicular adenopathy, and weight loss. Facial nerve palsy in the context of parotid swelling is a surgical emergency — it indicates malignant nerve invasion, which dramatically worsens prognosis. This must never be attributed to Bell's palsy without a clinical assessment specifically excluding parotid pathology.

The principle that antibiotics alone cannot treat a dental abscess is one of the most important — and most frequently violated — principles in GP antibiotic stewardship. A dental abscess is a closed space infection in an avascular, necrotic environment. Antibiotics penetrate avascular tissue poorly and cannot physically drain the pus — the abscess will recur as soon as the antibiotics are discontinued. The definitive treatment is drainage (via tooth extraction, root canal treatment, or incision and drainage) and/or removal of the infected tooth. The GP's role is to direct the patient to urgent dental care; antibiotics are a temporary bridge only where indicated (spreading infection, systemic involvement, significant trismus, no prompt drainage or high risk). Prescribing repeated courses of antibiotics for recurrent dental pain without dental referral is a major driver of antibiotic resistance and does not address the underlying problem. Every patient with a dental abscess must be given an urgent dental appointment — NHS 111 provides access to out-of-hours emergency dental services. For the RCGP SCA examination, being able to explain this distinction clearly to a patient who "just wants antibiotics" is a high-yield communication scenario. The icatibant mechanism is important — it is a synthetic decapeptide that competitively antagonises bradykinin B2 receptors, preventing the vasodilation and vascular permeability that bradykinin causes. It is licensed for acute hereditary angio-oedema attacks; any use, including for ACEi-induced angio-oedema, is a hospital/specialist decision according to the patient's established plan.

Heerfordt syndrome (uveoparotid fever) is a rare but clinically distinctive manifestation of sarcoidosis — the combination of bilateral parotid swelling, anterior uveitis, facial nerve palsy, and low-grade fever is virtually pathognomonic. It is important for GPs to recognise because it is frequently misdiagnosed: the parotid swelling is attributed to mumps (but it is bilateral, non-tender, and the patient is adult), the facial nerve palsy is attributed to Bell's palsy (but Bell's palsy is unilateral and not accompanied by parotid swelling), and the uveitis may be missed entirely. The combination of these four features should immediately trigger investigation for sarcoidosis: CXR (bilateral hilar lymphadenopathy), ACE level, serum calcium, and IGRA (to exclude tuberculosis as an alternative granulomatous diagnosis). Sjögren's syndrome is an underdiagnosed systemic autoimmune condition with frequent diagnostic delay. GPs should think of Sjögren's in any woman over 40 with persistent bilateral parotid swelling, dry eyes, and dry mouth — the combination is specific. The anti-Ro/anti-La antibody screen and referral to rheumatology should be arranged at first clinical suspicion. Sjögren's is associated with a significantly increased risk of B-cell lymphoma (particularly MALT lymphoma in the salivary glands) — making regular surveillance and referral for any new firm parotid mass in Sjögren's patients mandatory.

The frequency of sugar exposure (not total quantity) is the determinant of dental caries risk — Streptococcus mutans in dental plaque produces acid from sugar, which demineralises enamel. With very frequent sugar exposure (including sugary drinks, snacks, and fruit juices), the enamel has little time to remineralise (which requires salivary fluoride and a neutral pH). Limiting sugar to mealtimes (no sugary drinks between meals) reduces caries risk. This is why continuously sipping sugary drinks is more harmful than having a concentrated sugar dose at a meal. The GP's role in dental prevention — advising about sugar frequency, fluoride toothpaste, and registering with an NHS dentist — is explicitly part of the RCGP curriculum (Making Every Contact Count) and is frequently tested in SCA scenarios. Pilocarpine for Sjögren's xerostomia works by stimulating residual muscarinic M3 receptors in surviving secretory cells — it requires some residual gland function to work. Side effects are cholinergic: sweating, flushing, urinary frequency. It is contraindicated in asthma, narrow-angle glaucoma, and bradycardia. It must be initiated by a specialist (rheumatology or oral medicine) and then continued on GP repeat prescription.

Early reassessment of facial cellulitis and dental abscess with swelling matters — facial infections are uniquely dangerous because they are in close proximity to the orbit (orbital cellulitis) and the deep fascial planes of the neck and mediastinum (Ludwig's angina → descending necrotising mediastinitis). The progression from dental abscess to Ludwig's angina and from facial cellulitis to orbital cellulitis can be rapid with inadequate treatment. Written safety-netting instructions are essential for all patients with facial swelling managed at home — specifically: "If you develop difficulty opening your mouth, difficulty swallowing, voice changes, or your swelling rapidly increases, call 999 immediately." Head and neck cancer GP co-management is a growing and important part of the GP's role — treatment for head and neck SCC typically involves 6 weeks of concurrent chemoradiotherapy, which commonly causes severe mucositis, xerostomia, dysphagia, dermatitis, and profound fatigue. GPs manage: pain (opioids, local anaesthetic mouthwashes), nutrition (PEG tube feeding), mucositis (barrier preparations, analgesic gels), psychological distress (NHS Talking Therapies, Macmillan), and late effects (osteoradionecrosis of the mandible — avoid dental extractions without hyperbaric oxygen prophylaxis post-radiotherapy).