Oral infections - bacteria and spread Flashcards
What are the classical signs of acute inflammation?
Swelling Redness Pain or tenderness Heat Loss of function May also be systemic signs such as pyrexia, malaise, regional lymphadenopathy
What is an abscess?
A pus filled pathological cavity
Forms as part of the inflammatory response to acute infection
Acute exacerbations of chronic inflammation can also occur, followed by periods of quiescence
How to treat an abscess?
Drain it
How to differentiate abscesses and cellulitis?
Fluctuance to gentle palpation
2 fingers either side of swelling, press in the middle, if filled with fluid = it will bounce to other fingers = fluctuance
If no fluctuance = feels hard or does not bounce = cellulitis is present = does NOT need drainage
Radiographs to diagnose abscesses?
Diagnosis of an acute dentoalveolar abscess = usually by clinical means
Radiographs do not typically show any change in the periapical tissues
May be bcos it takes 10 days for sufficient bone loss to occur to be detectable on an intra-oral film
What is the earliest radiological sign of abscesses?
Widening of the periodontal ligament space, followed by loss of a normal lamina dura of the socket
Where does pus present from an apical abscess?
Pus from an acute dentoalveolar abscess takes the track of least resistance through the bone and to the nearest epithelial surface
Usually on the buccal aspect of the mx/md alveolus where the bone is thinnest
(but can be palatally/lingually)
Treatment principles of acute infection - general measures?
General measures:
- Admission to hospital if systemically unwell (malaise, pyrexia, tachycardia, hypotension) = need IV antibiotics, surgical drainage — NSAIDs for pain relief
- Analgesia
- Control of infection - typically amoxicillin and metronidazole are used in combo (changes made depending on microbiological results)
Treatment principles of acute infection - local measures?
Local measures:
- Removal of the cause but can be easier to drain and prevent spread in the acute phase (e.g. extraction of non-vital or hopeless prog tooth, foreign bodies, salivary calculi)
- Drainage - surgical incision
- Prevention of spread e.g. antibiotics
- Restoration of function when things settle
What indicates pus formation?
Reddening, fluctuance and a point of maximum tenderness
How to drain an abscess?
Adequate anaesthesia - 2% lignocaine with adrenaline injected into the overlying mucosa, not into the abscess cavity
Horizontal incision parallel to the occlusal surface of the teeth 1-2cm in length (remember local anatomy - nerves)
Use a no 11 blade held backwards with an upwards sweep
Open abscess cavity with artery forceps to get more drainage
Hot salt M/W to encourage pus to drain
When may drainage through an incision not be suitable?
When pus has to pass through several tissues planes to escape e.g. deep neck abscesses, you can insert a drain into the abscess cavity with is exteriorized into the mouth or onto the skin surface
How to prevent spread of infection?
Drainage, use of antimicrobials and rest (difficult in orofacial region, but trismus can help it)
Why review the pt post tx of abscess?
Review pt after the acute phase to ensure things have settled and function has been restored
Sometimes trismus can persist `and need for tx e.g. therabite
Typical bacteria causing abscesses?
Black pigmented anaerobes Fusoacterium Anaerobic cocci Streptococcus Non-pigmented anaerobes Eubacterium Spirochaetes
Periodontal abscess symptoms?
Pain
Swelling - small localised to diffuse
Lymphadenopathy and fever
Facial or neck cellulitis rare
What can cause a periodontal abscess?
Tooth usually vital
- Pre-existing periodontal pockets that become occluded (foreign body)
- Trauma to periodontium
- 2ndry infection of lateral periodontal cyst
Periodontal abscess - radiological features and microbial aetiology?
Radiolucency on lateral aspect of root
Microbial aetiology - same as chronic perio and candida
When can multiple perio abscesses occur?
Multiple perio abscesses seen in poorly controlled diabetes
Tx of periodontal abscesses?
Drain and debride
Streptococcal gingivostomatitis?
Rare in non-compromised hosts
- Most frequently follows tonsillitis
Severe inflammation of gingivae with pain
What causes Streptococcal gingivostomatitis? Complications of this?
Caused by Strep pyogenes
Complications:
- Fasciitis, tissue destruction, rheumatic heart disease, nephritis
Streptococcal gingivostomatitis treatment?
Penicillin
Acute ulcerative gingivitis risk factors?
Poor OH, smoking, stress
Acute ulcerative gingivitis signs/symptoms?
Microbial aetiology?
Ulceration and destruction of interdental papilla
- Invasion of tissue
Halitosis, bad taste, malaise, lymphadenopathy
Causes:
- Treponema vincentii
- Fusobacterium species
- Prevotella intermedia
Cancrum oris - what causes it?
Ususally preceded by ANUG and recent debilitating illness - Infection Viral (measles) Bac infec (tuberculosis, scarlet fever) Parasitic infec (malaria) - Immune suppressive drugs/disease - Malnutrition
Cancrum oris - what bacteria causes it?
F.necrophorum P.intermedia T.vincentii T.denticola T.forsythia Alpha streptococci
Tuberculosis?
Increasing incidence in UK particularly among immigrants
Rare in oral cavity
- Usually 2ndry to pulmonary TB
- Cough or cervical lymphadenopathy
Tuberculosis presentation and what can it cause?
Oral ulceration on tongue
Can result in delayed healing after tooth extraction or cause 2ndry osteomyelitis
Tuberculosis investigations?
Biopsy - Ziehl Neelson stain
Culture on LJ but takes 4-6 weeks
Serology, PCR (main way) reactive T cells
Tuberculosis histology?
Epitheliod granulomas = necrotic tissue
Giant cells and caseation (cheese like consistency)
Syphilis - primary lesion signs?
Primary lesion
- Chancre on lip or tongue
- Ulcer, local oedema, painless
- Smear shows spirochaetes
- Lymphadenopathy
Secondary syphilis - when does it occur?
6 weeks after healing
Secondary syphilis signs?
Snail track ulcers = long, spread out ulcers
Lymphadenopathy
Skin rash
Tertiary syphilis signs?
Rare
Gumma (= tissue nodule with a necrotic centre) on palate, tongue or tonsil
- Firm, necrotic centre surrounded by inflamed tissue
- Leukoplakia on dorsum of tongue and increased incidence of oral cancer
Congenital syphilis - dental signs?
Hutchinson’s incisors = dents in incisors
Mulberry molars = multiple crowns to molars
Gonorrhoea oral signs and symptoms?
Pharynx and any part of oral mucosa can be affected Pain and lymphadenopathy Variable appearance - Ulceration - Oedema - Pseudomembranes
How to diagnose gonorrhoea? What causes it?
Smear or culture to diagnose Neisseria gonorrhoea
Actinomycosis
Lumps at angle of mandible
What causes actinomycosis? How does this bacterium present?
Actinomyces israeli
Gram positive branched organism
Locules of pus surrounded by fibrous septa
Tx for actinomycosis?
Surgical drainage and debridement
Antibiotics 6-8 weeks
Acute bacterial sialadenitis?
Ascending infection - mainly parotid
Usually failure of secretion
- Sjogren’s syndrome, gland pathology, sialolithiasis, drugs
Unilateral, firm, red swelling, extreme pain, trismus, milking duct releases pus
Microbial causes of Acute bacterial sialadenitis?
Oral streptococci
Oral anaerobes
Staphylococcus aureus
Treatment for acute bacterial sialadenitis?
Amoxicillin, flucloxacillin
Exploration - sialography after resolution, possibly surgical exploration
Angular cheilitis causes?
Haematologyical deficiency - Fe, vitamin B2, 3, 6, 12
Candida sp, staph aureus (strep pyogenes)
Tx for angular cheilitis?
Miconazole, nystatin, flusidic acid depending on the cause
What determines the spread of dentoalveolar infections?
The site of origin and the surrounding tissue planes that are limited by fascial layers and muscle insertions
Position of the apices of the originating tooth relative to muscles and fascia will influence the clinical presentation
How do fascial planes and tissue spaces impact the spread of infection?
Neck is surrounded by multiple layers of fascia of which the deep cervical fascia is the most important
Fascial layers split around structures to form tissue paces
Fascial planes and tissue spaces determine the spread of infection
What are the 3 separate parts to the deep cervical fascia?
The investing layer = most external
- attaches to L and B maxilla, M of M, parotid gland, SCM and trapezius
Visceral layer
- Forms fibrous barrier outside of throat
- Outside pharynx constrictor muscles
Prevertebral fascia
- Wraps around muscles external to the spine
What impacts the spread of infection in the mandible?
Depends on the relation of the tooth to the insertion of 2 muscles - buccinator and mylohyoid
Buccinator attaches to lateral (buccal) cortex of mandible, adjacent to molars
Mylohyoid attaches to mylohyoid ridge, on the medial (lingual) cortex
Abscesses that track laterally, above buccinator point in the mouth
Below buccinator point onto the facial skin
Abscesses the track medially above mylohyoid point in the sublingual space (floor of mouth)
Below mylohyoid point into the submandibular space
Where can infections from the lower 7 and 8 track to?
Track posteriorly into either the masticator space or the parapharyngeal/retropharyngeal spaces
A sub-masseteric abscess causes profound trismus and the pt will not be able to open mouth
Spread into parapharyngeal and/or retropharyngeal spaces is dangerous due to possible airway compromise and tracking of pus into the check via the retropharngeal space
How can infection spread in the maxilla?
Most maxillary dental abscesses track buccally as bone is thinnest here, to point in the mouth
BUT abscesses arising from upper laterals and palatal roots of 1st molars can paint palatally
Relationship between tooth apices and the levator anguli oris and buccinator muscles determines whether the abscess points in oral cavity or the skin of the cheek
Apex of the upper canine tooth can be situated above the origin of the levator anguli oris = infec can present at the medial canthus of the eye, deep to levator labii superioris
Deep neck space infection?
Rare
Most are dental in origin
Typically from mandibular 7 and 8 as their apices are often below the mylohyoid muscle
Deep neck space infection signs/infection?
Fever Pain Sore throat Difficult or painful swallowing (dysphagia) Trismus
How to manage deep neck space infections?
Same as intraoral but defo:
- Airway management
- Intravenous antibiotic
- Surgical drainage
Complications of orofacial infection?
Cavernous sinus thrombosis
- Surrounds pituitary gland
- Blood from orbits, skull vault and cerebral hemispheres
- Infec from upper anterior tooth can rarely drain into cavernous sinus = venous thrombosis
Cavernous sinus thrombosis signs/symptoms?
Opthalmoplega (no eye movements)
Ptosis (drooping upper lid)
Proptosis (bulging eye)
Chemosis (red eye)
When are antibiotics indicated?
When systemic symptoms present
- Fever, malaise, nausea
Spreading infecs
Chronic infec despite drainage e.g. actinomycosis
If immuno or medically compromised
Conditions difficult to resolve without or that speed up recovery - osteomyelitis, ANUG, sialadenitis
How to use antimicrobials?
Aimed at organism present
Dose achieve 4-8 times the minimum inhibitory conc in blood
Must be present long enough to penetrate the site - but not too long
Selection of antimicrobial agent?
Broad spec agents
- Associated with rise in C.difficile disease = care when Rx to elderly and GI disease (including proton pump inhibitors and reflux disease)
Empirical use
- Main drugs are amoxicillin, pen V, metronidazole and erythromycin
- Clindamycin, co-amoxiclav, clarithromycin no advantage
When to not prescribe antimicrobials?
Do not prescribe for
- Pulpitis
- Prevention of dry socket (unless pt immunocompromised in difficult extraction)
Why may antibiotics fail?
Agent does not reach site
- Inadequate drainage
- Poor blood supply
- Presence of foreign body
- Inadequate duration
Impaired defences
- Immunocompromised (bacteriostatic agent used)
Inappropriate agent - resistance
- Inherit resistance or acquired (mutation, plasmids)
Poor pt compliance
