odontogenic infections Flashcards
Factors contributing to immunity of host against intra oral infections
- Humoral: circulating immunoglobulins, promote phagocytosis by macrophages. Inflammatory mediators
- Cellular: phagocytes, lymphocytes
- Local: abundant vascular supply, mechanical cleansing by salivary flow, igA, high epithelial turnover
Progression of odontogenic infection
- inoculation
- cellulitis – 5 cardinal signs of inflammation . diffuse redness and soft at early stage, hard after 24 h
- abscess
- resolution
When is aggressive/prompt treatment of odontogenic infection required
- 24 hour painful swelling ie rapid
- pain on swallowing
- severe trismus (0-5mm opening)
- pediatric patient
- dyspsnea
pain durning swallowing indicates that odontogenic infection has
gone backwards to involve epiglottis and pharyngeal mucosa
Severe trismus indicates that odontogenic infection has
involved the muscles of mastication (masticator space), which can progress to involve the lateral pharyngeal space –> retropharyngeal space –> danger space –> go down to mediastinum and cause mediastinitis
Factors affecting path of spread of odontogenic infection
Thinness of bone
Location of apex
Insertion of muscle
If apex of lower molar is above insertion of mylohyoid, infection spreads to
sublingual space
If apex of lower molar is below insertion of mylohyoid, infection spreads to
submandibular space
Odontogenic infection of central incisor can spread to
Canine space –> infraorbital space –> angular vein –> cavernous sinus thrombosis
Orbital space has two compartments. Preseptal is superficial. Once it goes past orbital septum, must treat aggressively as highway to cavernous sinus
What is ludwig’s angina
odontogenic infection spreads backwards to involve submandibular space –> r/l submental –> contralateral submandibular space –> r/l sublingual space ie bilateral involvement of submand and sublingual space
Tongue is pushed upwards and backwards which obstructs breathing and causes asphyxiation. Hence accessory muscles of inspiration are engaged
When FOM palpated, hard, cannot be depressed
Palatal abscess likely to originate from which teeth
Palatal root of upper molar
Upper lateral incisor
What happens when there is odontogenic infection buccal space involvement
Reduced mouth opening of 15-25mm due to guarding. Mouth opening improve when LA given (not true trismus)
Masseteric space infection typically originate from
lower molars
What kind of radiograph do you take to investigate odontogenic infection
CT scan
Treatment for odontogenic infection
- Identify cause
- Determine severity eg trismus time of onset, vital signs (>38.5º and elevated heart rate, fever, malaise indicate systemic involvement), is tissue fluctuant/indurated, distortion of tissue architecture eg soft palate deviation indicate involvement of lateral pterygoid space
Complications of odontogenic infections
- Meningitis
- Encephalitis
- Base of skull
- Spread to cavernous sinus after spreading past orbital septum
- Air way embarrassment
- Septic thrombosis
Principles in treatment of odontogenic infection
- Setting of treatment (do you refer to OMS)
- Protect airway
- Remove cause
- Establish drainage
- Antibiotic therapy
- Suppportive care
When to refer to OMS for treatment of odontogenic infection
Moderate infection with some buccal space involvement and patient not immunocompromised –> either GP/OMS
Moderate infection with immunocompromised eg diabetes patient –> OMS
Severe eg difficulty breathing, >38.5ºC, severe trismus –> OMS
How to protect air way in patient with odontogenic infection as GP
Ambubag, posture of patient
LA infiltration may not be effective in patient with odontogenic infection due to increased acidity of environment. What should you do?
Give block
Sodium bicarbonate buffer
How to give LA to patient suffering from trismus
Mouth prop with conventional IDN block
Closed mouth akinosi technique
In patient with odontogenic infection, trismus is most often caused by
Guarding
Spasm of masticatory muscles
How long does it take for Ab to show effect
48 hours
Drain options for incision and drainage
Rubber dam, fingers of glove, penrose drain
Suture drain to surrounding mucosa to anchor it
Instructions for giving antibiotics for patient with odontogenic infection
Effecs only after 48 hours
Give for at least one week
Choose bacteriocidal antibiotic
Adequate tissue concentration achieved in 24-48h
Empirical antibiotics likely enough for simple cases
Drug of choice for odontogenic infection
Penicillin (first line)
Clindamycin (first line after penicillin)
Erythromycin (bacteriostatic, second line after penicillin)
principles of odontogenic infection management
Secure airway, early and aggressive drainage of all anatomic spaces affected by cellulitis or abscess
natural history of infection
First stage is inoculation, where bacteria begins to spread beyond local confines. Patient may experience mild to moderate pain. Edema begins to occur, wth interstitial fluidbuikd up from neighbouring infection/inflammation
Second stage is cellulitis ie spread of bacteria into a space along with interstitial fluid formation. Inflammation (5 cardinal signs) is underway, and begins to overwhelm the host defense. Patient experiences more severe and generalised pain.
Third stage is abscess formation. Maturation of inflammatory response is achieved and there is focal accumulation of purulent discharge. Severe focal pain
Lastly, resolution
pain on swallowing indicates involvement of
epiglottis and pharyngeal mucosa
source of buccal space swelling
upper molars, premolars
lower premolars
where can buccal space abscess spread to
infratemporal space
infraorbital space
pterygomandibular space
clinical signs of ludwigs angina
fluctuant swelling may be present, firm induration of skin at the submental and submandibular region extraorally, elevation of FOM and tongue
patient can present with airway distress (use of accessory muscles for inspiration), trismus, dysphagia, dysphonia
