Fascial Spaces and Odontogenic Infections – Review Flashcards

Flashcards covering definitions, classifications, anatomy, clinical features, microbiology, pathways, management, and complications of fascial space infections in the head and neck.

What is a fascial space?

A potential space in the head and neck filled with loose connective tissue that can accumulate pus and allow predictable spread of infection.

Why don’t odontogenic infections spread randomly in the head and neck?

They follow predictable pathways through communicating fascial spaces filled with loose connective tissue.

Give two main functions of fascia in the head and neck.

(1) Separate structures that move over each other (e.g., muscles, glands) and (2) provide pathways for vessels and nerves.

List the primary maxillary fascial spaces.

Canine, buccal, infratemporal, and vestibular/palatal spaces.

List the primary mandibular fascial spaces.

Submental, sublingual, submandibular, buccal, and vestibular spaces.

Name at least four secondary fascial spaces of odontogenic importance.

Masseteric, pterygomandibular, superficial temporal, deep temporal, lateral pharyngeal, retropharyngeal, parotid, carotid sheath, prevertebral.

Which fascial spaces together make up the masticator space?

Masseteric (submasseteric), pterygomandibular, superficial temporal, and deep temporal spaces.

Boundaries of the canine space (superior and inferior)?

Superior – levator labii superioris alaque nasi and levator labii superioris; Inferior – caninus (levator anguli oris) muscle.

Typical source of infection for the canine space.

Maxillary canine or first premolar infections (may also involve mesiobuccal root of first molar).

Key clinical signs of canine space infection.

Swelling of cheek, lower eyelid, and upper lip; obliterated nasolabial fold; drooping mouth angle; lower-lid edema.

Main contents of the buccal space.

Buccal fat pad, Stenson’s (parotid) duct, and facial artery.

Classic external appearance of combined buccal and temporal space infection.

Dumb-bell-shaped swelling with sparing over the zygomatic arch.

What muscles form the medial boundary of the buccal space?

Buccinator muscle and buccopharyngeal fascia.

Source teeth most often causing buccal space infections.

Infected mandibular or maxillary premolars and molars.

Define a palatal space abscess and preferred incision orientation.

Subperiosteal abscess on the hard palate; incision parallel to greater palatine vessels.

Main contents of the infratemporal space.

Pterygoid plexus of veins, internal maxillary artery, mandibular nerve and branches.

Most common dental source for infratemporal space infection.

Infected maxillary third molar.

Serious vascular complication arising from infratemporal infection via the pterygoid plexus.

Cavernous sinus thrombosis.

Which three signs suggest infratemporal space infection?

Extra-oral swelling over sigmoid notch, intra-oral swelling in tuberosity region, and trismus.

Roof and floor of the submental space.

Roof – mylohyoid muscle; Floor – deep cervical fascia, platysma, superficial fascia, and skin.

Likely odontogenic source for submental space infection.

Infected mandibular incisors.

Two hallmark symptoms of submental space infection.

Glossy swollen chin and pain on swallowing.

Boundaries of the sublingual space (superior and inferior).

Superior – oral mucosa of floor of mouth; Inferior – mylohyoid muscle.

Why does sublingual space infection elevate the tongue?

Pus accumulation above the mylohyoid lifts the floor of mouth, pushing the tongue upward.

Name two major glands located in the sublingual space.

Sublingual gland and deep part of the submandibular gland.

Most frequent teeth causing submandibular space infection.

Mandibular second and third molars whose roots lie below the mylohyoid line.

Classic presentation of submandibular space infection.

Indurated swelling below mandibular angle bulging over the inferior border of the mandible.

What is the key clinical difference between sublingual and submandibular abscess?

Sublingual abscess elevates the tongue; submandibular abscess presents as extraoral swelling below the mandible.

Source and symptom triad of masseteric (submasseteric) space infection.

Source – mandibular third molar (pericoronitis); Symptoms – swelling over masseter, severe trismus, throbbing pain.

Which neurovascular bundle lies within the pterygomandibular space?

Inferior alveolar nerve, artery, and vein (plus lingual & auriculotemporal nerves).

Key intra-oral sign of pterygomandibular space infection.

Bulging of one half of soft palate and tonsillar pillar with uvula deviated to opposite side; no external swelling.

Temporal space is divided into which two compartments and by what structure?

Superficial and deep temporal spaces, separated by the temporalis muscle.

Primary sources of infection that reach the temporal spaces.

Spread from infratemporal or pterygomandibular spaces.

Describe the shape and apex/base of the lateral pharyngeal space.

Inverted cone/pyramid with base at the sphenoid bone and apex at the hyoid bone.

Structures contained in the posterior (vascular) compartment of the lateral pharyngeal space.

Carotid sheath – carotid artery, internal jugular vein, vagus nerve – plus cranial nerves IX–XII.

Serious vascular complication possible in lateral pharyngeal space infection.

Thrombosis of internal jugular vein or erosion of carotid artery.

Boundaries of the retropharyngeal space (anterior and posterior).

Anterior – posterior pharyngeal wall (buccopharyngeal fascia); Posterior – prevertebral fascia.

Why is the retropharyngeal space called a ‘dangerous’ pathway?

It can descend directly into the posterior mediastinum, leading to life-threatening mediastinitis.

List four cardinal clinical features of retropharyngeal abscess.

Neck stiffness, dyspnea, dysphagia, bulging of posterior pharyngeal wall.

Differentiate cellulitis from abscess on palpation.

Cellulitis feels doughy/indurated with diffuse borders; abscess is fluctuant and well circumscribed.

Common aerobic and anaerobic bacteria in odontogenic infections.

Aerobic – alpha-hemolytic Streptococcus species; Anaerobic – Prevotella, Bacteroides, Fusobacterium.

Define Ludwig’s angina.

Rapidly spreading bilateral infection of submandibular, sublingual, and submental spaces causing airway compromise.

Three goals of managing odontogenic infections.

Protect airway, surgically drain infection/remove cause, and institute appropriate antibiotic/medical therapy.

First-line empirical antibiotic for odontogenic infections; alternative for penicillin-allergic patients.

Parenteral penicillin; alternative – clindamycin.

Why can antibiotics never replace incision and drainage in significant abscesses?

Pus and necrotic debris impede antibiotic penetration; drainage removes pressure and restores blood flow/oxygenation.

State two indications for incision and drainage.

Presence of fluctuance/pus accumulation and deep fascial space infection inaccessible by simple extraction or endodontics.

Describe Hilton’s method of abscess drainage.

Stab incision through skin/mucosa; blunt dissection with sinus forceps parallel to vital structures; break loculi, irrigate, place drain.

Purpose of placing a drain after incision.

Keeps wound patent for continuous pus/fluid egress and allows postoperative irrigation.

List three factors that affect the spread of odontogenic infection.

Microbial virulence and load, host immune status, and medical intervention (e.g., antibiotics/surgery).

Two main routes of indirect spread of odontogenic infection.

Lymphatic spread to regional nodes and hematogenous spread to distant organs (e.g., cavernous sinus, endocardium).

Name four severe complications of uncontrolled odontogenic infection.

Ludwig’s angina, cavernous sinus thrombosis, mediastinitis, osteomyelitis (others: necrotizing fasciitis, sepsis).

What is the ‘danger triangle’ of the face?

Area from corners of mouth to bridge of nose where infections can spread via facial/ophthalmic veins to cavernous sinus.

Define cellulitis.

Diffuse, acute, spreading inflammatory process of soft tissue without pus formation, often aerobic bacteria predominance.

Define abscess.

Localized collection of pus within a pathological cavity, usually chronic, fluctuant, and anaerobe-rich.

When is combination antibiotic therapy indicated in odontogenic infections?

To broaden spectrum, enhance bactericidal effect, prevent resistance, or treat severe rapidly progressing infections.

Key clinical signs requiring urgent airway management in fascial space infections.

Difficulty breathing, drooling, stridor, rapidly enlarging floor-of-mouth swelling, or bilateral submandibular involvement.