This document provides an overview of infections that can occur in the mandibular spaces of the head and neck region. It classifies mandibular spaces based on mode of involvement and clinical significance. It then describes in detail the anatomy, clinical features, and treatment of infections in the submental, submandibular, sublingual, masseteric, and pterygomandibular spaces. Secondary spaces that mandibular infections can spread to are also mentioned. The document aims to educate on the fascial spaces of the lower jaw and odontogenic infections that involve these spaces.

1. MANDIBULAR SPACE
INFECTIONS
Submitted by
Sooraj suresh
REG NO:180020610

2. CONTENTS
 INTRODUCTION
 CLASSIFICATION
 SUBMENTAL SPACES
 SUBMANDIBULAR SPACE
 SUBLINGUAL SPACE
 TEMPORAL SPACE
 PTERYGOMANDIBULAR SPACE
 SUBMASSETRIC SPACE
 CONCLUSION
 REFERENCE

3. INTRODUCTION
 The head and neck region has structures separated from each other through
specific natural connective tissue barriers called fascia. (Fascia means fibrous
connective tissue which binds together various structures of the body). These
fascial layers can be anatomically divided into superficial and deep. The
fascial spaces are potential spaces formed by the various fascial layer’s
division and unions at different levels.

4. • CLASSIFICATION OF SPACES
 Based on the Mode of Involvement
 Direct involvement: Primary spaces— (a) maxillary spaces (b) mandibular spaces.
 Indirect involvement: Secondary spaces.
 Spaces involved in Odontogenic Infections
 Primary maxillary spaces: Canine, buccal, and infratemporal spaces.
 Primary mandibular spaces: Submental, buccal, submandibular, and sublingual
spaces.
 Secondary fascial spaces: Masseteric, pterygomandibular, superficial and deep
temporal, lateral pharyngeal, retropharyngeal, and prevertebral spaces, parotid
space.
 Based on Clinical Significance
 Face—buccal, canine, masticatory, parotid
 Suprahyoid—sublingual, submandibular (submaxillary, submental),
pharyngomaxillary (lateral pharyngeal), peritonsillar
 Infrahyoid—anterovisceral (pretracheal)
 Spaces of total neck—retropharyngeal, space of carotid sheath.

5. • SPACES RELATED TO LOWER JAW
 SUBMENTAL SPACE
 SUBMANDIBULAR SPACE
 SUBLINGUAL SPACE

6. SUBMENTAL SPACE INFECTION
 INVOLVEMENT
 Infection from lower incisors, lower lip, chin, tip of the
tongue and anterior part of floor of the mouth can
spread to the submental lymph nodes and subsequently
cause infection of the submental space.
 BOUNDARIES
 Superior—Mylohyoid muscle
 Inferior—Skin and subcutaneous tissue, platysma and
deep cervical fascia
 Medial—Single midline space with no medial wall
 Lateral—Anterior belly of digastric (bilateral)
 Anterior—Mandible
 Posterior—Hyoid bone

7.  CONTENTS
 Submental lymph nodes, and anterior jugular veins. The lymph
nodes lie embedded in adipose tissue, and hence, submental
abscesses tend to remain well circumscribed
 CLINICAL FEATURES
 EXTRAORAL : Distinct, firm swelling in midline, beneath the chin.
Skin overlying the swelling is board like and taut. Fluctuation may
be present.
 INTRAORAL : The anterior teeth are either nonvital, fractured or
carious. The offending tooth may exhibit tenderness to percussion
and may show mobility. The patient may experience considerable
discomfort on swallowing.
 INCISION AND DRAINAGE
 It is performed by making a transverse incision in the skin below
the symphysis of the mandible. Blunt dissection is carried out by
inserting a Kelly’s forceps or sinus forceps through this incision,
upward and backward. A small piece of corrugated rubber drain is
inserted in the abscess cavity, and is secured to one of the margins
of the wound with a suture.

8. • SUBMANDIBULAR SPACE
 INVOLVEMENT
 It is involved most frequently by infections originating from
the mandibular molars. The pus perforates the lingual cortical
plate of mandible, inferior to the attachment of mylohyoid
muscle, and passes directly into the submandibular space.
 The infection from the submandibular salivary gland may pass
via lymphatics to the submandibular lymph nodes.
 It is also involved, as an extension of infection from submental
space; or from the submental lymph nodes via the lymphatics
 It is also involved from infection originating from middle third
of the tongue, posterior part of the floor of the mouth,
 Maxillary teeth,
 Cheek,
 Maxillary sinus and
 Palate.

9.  BOUNDARIES
 Lateral—Skin, superficial fascia, investing fascia,
platysma
 Medial—Mylohyoid, hyoglossus, superior constrictor,
styloglossus muscles
 Superior—Inferior and medial surface of the mandible
and attachment of mylohyoid muscle
 Inferior—Anterior and posterior belly of digastrics
muscle
 CONTENTS
• Submandibular salivary gland and lymph nodes
• Facial artery
• Lingual nerve
• Lymph nodes

10.  CLINICAL FEATURES
 Extraoral: (i) Firm swelling in submandibular region, below the inferior
border of mandible, (ii) generalized constitutional symptoms, (iii) some
degree of tenderness, (iv) redness of overlying skin.
 Intraoral: (i) Teeth are sensitive to percussion, (ii) teeth are mobile,
(iii) dysphagia, and (iv) moderate trismus.
 INCISION AND DRAINAGE
 An incision of about 1.5–2 cm length is made 2 cm below the lower
border of mandible, in the skin creases. Skin and subcutaneous tissues
are incised. A sinus forceps is inserted through the incision superiorly
and posteriorly on the lingual side of the mandible below the mylohyoid
to release pus from submandibular space. A corrugated rubber drain is
inserted in the abscess cavity and is secured with a suture and dressing
is applied.
 SPREAD
 There are no major anatomic barriers between the two submandibular
and submental spaces. Hence, infection can extend into the submental
space.

11.  Contralateral submandibular space.
 Infection can spread backwards to involve para-
pharyngeal spaces

12. • SUBLINGUAL SPACE
 INVOLVEMENT
 The teeth which frequently give rise to involvement
of sublingual space are the mandibular incisors,
canines, premolars and sometimes first molars. The
apices of these teeth are superior to the mylohyoid
muscle. The infection perforates lingual cortical
plate below the level of the mucosa of the floor of
the mouth and passes into the sublingual space.
 CONTENTS
 Deep part of submandibular gland
 sublingual gland and their draining ducts (Wharton’s
duct and ducts of Rivinus)
 Lingual nerve

13.  BOUNDARIES
 Superior—Mucosa of the floor of the mouth
 Inferior—Superior surface of mylohyoid muscle
 Medial—Midline raphae
 Lateral—Medial surface of mandible
 CLINICAL FEATURES
 Extraoral: There is little or no swelling. The lymph nodes
may be enlarged and tender. Pain and discomfort on
deglutition. Speech may be affected.
 Intraoral: Firm, painful swelling seen in the floor of the
mouth on the affected side. The floor of the mouth is
raised. The tongue may be pushed superiorly. This will
bring about airway obstruction. The ability to protrude
the tongue beyond the vermillion border of upper lip is
affected.

14.  INCISION AND DRAINAGE
 Intraorally: An incision is made close to the lingual
cortical plate, lateral to the sublingual plica, as the
important structure at this site is the sublingual nerve
which is deeply placed and less likely to be damaged
by this approach. The other important structures lie
medial to the plica and include the Wharton’s duct,
sublingual artery and veins and the lingual nerve. The
sinus forceps is then inserted and opened to evacuate
the pus.
 Extraorally: When both the submental and sublingual
spaces contain pus, they can be drained via a skin
incision placed in the submental region, pushing a
closed sinus forceps through the mylohyoid muscle.
Similarly, when the submandibular space is involved, a
sublingual space abscess can be approached and
drained through an incision in the skin overlying the
submandibular space, via the submandibular space

15. SECONDARY MANDIBULAR SPACES
 MASSETRIC SPACE
 PTERYGOMANDIBULAR SPACE
 TEMPORAL SPACE

16. • MASSETRIC SPACE
 BOUNDARIES
 Anterior—Buccal space, parotidomasseteric
fascia
 Posterior—Parotid gland and its fascia
 Superior—Zygomatic arch
 Inferior—Inferior border of mandible
 Superficial or medial—Ascending ramus
 Deep or lateral—Masseter muscle

17.  CONTENTS
 Masseteric nerve, superficial temporal artery, and transverse facial
artery.
 It contains muscles of mastication; masseter, lateral and medial
pterygoids, and insertion of temporalis muscle.
 INVOLVEMENT
 Infection usually originates from the lower third molars; either
resulting from (i) pericoronitis related to vertical and distoangular
3rd molars or (ii) a periapical abscess spreads subperiosteally in a
distal direction.
 CLINICAL FEATURE
 Extraorally, the swelling is seen mainly over the angle of the
mandible. It is restricted to the masseter muscle as the forward
spread is confined by the tendon of temporalis, which is inserted
into the anterior border of the ramus. The lower border of the
ramus controls inferior spread. Sometimes the posterior mandibular
sulcus may be obliterated.

18.  The infection is characterised by severe trismus and
throbbing pain. Chronic submasseteric space infection can
be punctuated by recurrent exacerbation, which can be
controlled through drainage and antibiotics but without a
complete resolution. The masseter muscle is more
responsible for blood supply of ramus of the mandible than
the body, which is mainly supplied by mandibular artery.
Because of this, ischaemia results in that part of the bone
denuded of periosteum by the abscess, which leads to
osteomyelitis with sequestrum formation.
 NEIGHBOURING SPACE
• Buccal space
• Pterygomandibular space
• Superficial temporal space
• Parotid space
• Infratemporal space

19.  INCISION AND DRAINAGE
 Intraoral approach: An incision is made vertically over the lower part
of anterior border of the ramus of the mandible, deep to the bone. A
sinus forceps are passed along the lateral surface of the ramus
downwards and backwards and the pus is drained. The drain is
inserted and secured with a suture. The abscess is usually situated
below the level of incision, and not at a point of dependent drainage,
and hence the drainage may be inefficient.
 Extraoral approach: When the mouth cannot be opened, an incision
is placed in the skin behind the angle of the mandible to open the
abscess by Hilton’s method. A rubber drain is inserted and secured in
position with a suture.

20. • PTERYGOMANDIBULAR SPACE
 CONTENTS
 Lingual nerve, mandibular nerve, inferior
alveolar or mandibular artery. Mylohyoid nerve
and vessels. Loose areolar connective tissue.
 INVOLVEMENT
 The situation most frequently responsible for
involvement of this space, is the pericoronitis
related to the mandibular 3rd molar.
 Infection can also be produced by a
contaminated needle used for an inferior
alveolar nerve block.
 Infection, at times, can originate from a
maxillary 3rd molar, following a posterior
superior alveolar nerve block injection.

21.  BOUNDARIES
 Anterior—Buccal space
 Posterior—Parotid gland with lateral pharyngeal space
 Superior—Lateral pterygoid muscle
 Inferior—Inferior border of mandible
 Superficial or medial—Lateral surface of medial pterygoid
muscle
 Deep or lateral—Medial surface of ascending ramus of
mandible
 NEIGHBOURING SPACE
• Buccal space
• Lateral pharyngeal space
• Submasseteric space
• Deep temporal space
• Parotid space
• Peritonsillar space

22.  CLINICAL FEATURES
 Extraorally, the swelling is not very obvious. Intraorally, there is visible
swelling of the soft palate on the same side, swelling of the anterior
tonsillar pillar and deviation of the uvula to the opposite side. The
patient has severe trismus and dysphagia. Therefore in cases of
pterygomandibular space infection, we have to carefully examine
intraorally using anaesthetic spray to arrive at a proper diagnosis.
 INCISION AND DRAINAGE
 Intraoral: A vertical incision, approximately 1.5 cm in length, is made
on the anterior and medial aspect of the ramus of mandible. A sinus
forceps in inserted in the abscess cavity, opened and closed and
withdrawn. The pus is evacuated, a rubber drain is introduced and is
secured in position with a suture.
 Extraoral: An incision is taken in the skin below the angle of the
mandible. A sinus forceps is inserted towards the medial side of the
ramus in an upward and backward direction. Pus is evacuated and the
drain is inserted from an intraoral approach and sutured in position.

23. • TEMPORAL SPACE
 INVOLVEMENT
 Involvement is secondary to the initial involvement of
pterygopalatine and infratemporal spaces.
 CONTENTS
 Superficial temporal vessels, auriculotemporal nerve and
temporal fat pad
 BOUNDARIES
 Laterally—Temporal fascia
 Medially—Temporal bone

24.  CLINICAL FEATURE
 Patient complains of severe pain and trismus. Swelling is more
obvious in the superficial temporal space infection and will be
restricted by the outline of the temporal fascia superiorly and
laterally and by the zygomatic arch inferiorly. In case of
associated buccal space infection, swelling has a characteristic
dumbbell shape due to absence of swelling over the zygomatic
arch. A deep temporal space infection produces less swelling and
there will also be pain and trismus.
 INCISION AND DRAINAGE
 Extraoral incision in temporal region, well above the hairline, 45°
to zygomatic arch. The hemostat is inserted above and below the
temporalis muscle.

25. CONCLUSION
 Infections of orofacial and neck region, particularly those of odontogenic
origin, have been one of the most common diseases in human beings. Despite
great advances in healthcare, these infections remain a major problem; quite
often faced by oral and maxillofacial surgeons. Early recognition of orofacial
infection and prompt, appropriate therapy are absolutely essential. A
thorough knowledge of anatomy of the face and neck is necessary to predict
pathways of spread of these infections and to drain these spaces adequately

26. REFERENCE
 NEELIMA MALIK 4TH EDITION
 SM BALAJI 3RD EDITION