1. By Dr. Mahdi Faour

2. Contents
Infection in general
Types of infection
Etiology of orofacial infections
Predisposing factors for acute oral infections
Microbiology
Routes of spread of infection
Anatomical factors influencing the direction of spread

3. Infection
Definition: Infection is the pathological
state resulting from the invasion of the
body by pathogenic microorganisms.
The reaction of the tissues to the presence
of these microorganisms and the toxins
generated by them is INFLAMMATION.

4. Types of Infection
 Bacterial Infection: not only one particular specie,
but due to a mixture of species which make up the
oral flora.
 Fungal Infection: Actinomycosis
 Viral Infection: Not recognized because they are
complicated early by secondary bacterial infection.
 Parasitic infection: Very rare( ex. Lyshmoniasis)

5. Etiology of Infection
The majority of oral, facial, and neck infections are
odontogenic in origin.
Although they may be caused by infections from
 Antrum (maxillary sinus)
 Major salivary glands
 Specific Infections of jaws (osteoradionecrosis,
osteomyelitis)

6. Odontogenic Causes of Infections
1. Decay (caries) reaching the dental pulp= pulpitis, this in turn
spreads to supporting bone resulting in periapical abscess which
in turn may spread subperiosteally.
2. Periapical abscess may occur in seemingly intact but devitalized
teeth (trauma, cracks or decay under fillings).
3. Periodontal diseases
4. Erupting teeth (especially partially impacted lower third molars)
can result in inflammation and infection of the gum flap
preventing eruption (operculum) with swelling pus etc. around
the crown (pericoronitis).
5. Retained roots supragingival or subgingival.

7. Predisposing factors for acute
oral Infections
I. Endocrine disturbances
II. Nutritional deficiency (decreases resistance)
III. Chemical compounds used in dentistry (arsenic)
IV. Blood disorders (leukemia, anemia)
V. General diseases (syphilis, TB)
VI. Immunological diseases (AIDS)
VII. Trauma
 Fractures of jaw
 Pressure type of anesthesia
 Improper use of surgical burs without cooling

9. Microbiology
Odontogenic infections are multimicrobial:
 Gram (+) cocci, aerobic and anaerobic:
 Streptococci and their anaerobic counterpart,
peptostreptococci
 Staphylococci, and their anaerobic counterpart,
peptococci
 Gram (+) rods:
 Lactobacillus, diphtheroids, Actinomyces
 Gram (-) rods:
 Fusobacterium, Bacteroids, Eikenella, Psuedomonas
(occasional)

10. Aerobic 25%
 Gram-positive cocci 85%
 Streptococcus spp. (90%)
 Streptococcus (group D) spp. (2%)
 Staphylococcus spp. (6%)
 Eikenella spp. (2%)
 Gram-negative cocci (Neisseria spp.) 2%
 Gram-positive rods (Corynebacterium spp.) 3%
 Gram-negative rods (Haemophilus spp.) 6%
 Miscellaneous and undifferentiated 4%

11. Anaerobic 75%
 Gram-positive cocci 30%
 Streptococcus spp. 33%
 Peptostreptococcus spp. 65%
 Staphylococcus spp. 65%
 Gram-negative cocci (Veillonella spp.) 4%
 Gram-positive rods 14%
 Eubacteriumspp.
 Lactobacillus spp.
 Actinomyces spp.
 Clostridia spp.
 Gram-negative rods 50%
 Bacteroides spp. 75%
 Fusobacterium spp. 25%
 Miscellaneous 6%

12. Rate of spread of infection
Rate depends on:
 Virulence of the invading microbes
 Dosage or number of these microbes
 Host resistance
Severity of infection=
(Virulence x Dose)/Resistance

13. Clinically odontogenic infections can be
distinguished in three periods:
 Period of periapical of dento-alveolar abscess
(in which the initial lesion develops)
 Period of extension to the adjacent bone and
facial spaces
 Period of serious complications (embolism,
septicemia, pyemia)

14. Routes of spread of infection
 By direct continuity through the tissues
Alveolar bone
Soft tissue
Fascial space
Caries
Pulpitis
Apical
infection

15.  By the lymphatics, to the regional lymph nodes and
eventually to the blood stream. If infection becomes
established in lymph nodes, then secondary abscess
may develop.

16.  By the bloodstream. Local thrombophlebitis may rarely propagate along
the veins, entering the cranial cavity via emissary veins to produce cavernous
sinus thrombophlebitis. Septicemia, pyaemia, and bacteraemia can be
caused by bloodstream spread. (N.B. Facial veins are valveless)
Hematogenous spread of infection from jaw to cavernous sinus may occur
anteriorly via inferior or superior ophthalmic vein or posteriorly via emissary
veins from pterygoid plexus.

17. Anatomical factors influencing the
direction of spread within tissue
1.The site of the source of infection (maxilla or mandible
and even the particular segment of the jaw).
2.The point at which pus escapes from the bone and
discharges into the soft tissues (linguopalatally or
labiobuccally).
3.The natural barriers to the spread of pus in the tissues,
such as by layers of fascia or muscle or the jaw bones
themselves.

18. Facial Spaces
 Fascial spaces are fascia-lined areas that can be eroded
or distended by purulent exudate.
 These areas are potential spaces that do not exist in
healthy people but become filled during infections.

19.  As infection erodes through bone, it can express itself in a variety of places,
depending on thickness of overlying bone and relationship of muscle
attachments to site of perforation. This illustration notes six possible locations:
1-vestibular abscess, 2-buccal space, 3-palatal abscess, 4-sublingual space,
5-submandibular space, and 6-maxillary sinus.

21. Principles of Treatment of
orofacial Infections

22. Principles of Treatment of
orofacial Infections
1.Remove the cause.
2.Establish drainage.
3.Institute antibiotic therapy.
4.Supportive care, including proper rest and
nutrition.

23. Basic Principles of Local Treatment
Surgical treatment of abscess and phlegmon is based on
the pus drainage, and therefore in all cases the
following steps should be followed.
IncisionIncision
1. Incision
Opening the abcess
2. Opening the abscess

24. 3.Taking of smear to
determine the bacteria
4.Drainage of abscess
Drainage of abscessDrainage of abscess

27. Abscess of Orofacial Spaces

29. Canine Fossa(infra-orbital)
Borders:
 Superior: inferior margin of the orbit
 Inferior: alveolar process of maxilla
 Mesial: margin of periform aperture
 Lateral: zygomatic-maxillary suture

30. Canine Fossa Infection
Odontogenic origin: maxillary canines and premolars
Nonodontogenic:
 Skin infections
 Trauma
 Hematoma
Infection can be superficial (due to dermatologic
infections) or can be deep (between muscles and
bone-odontogenic infection), and the infections
quickly spreads from superficial to deep and vice
versa.

31. Clinical Presentation (canine Fossa)
 Edema, localized in the infraorbital region, which
spreads towards the lower eyelid and side of the nose
as far as the corner of the mouth.
 There is also obliteration of the nasolabial fold, and
somewhat of the mucolabial fold.
 The edema at the infraorbital region is painful and
there is fluctuation during palpation, and later on the
skin becomes taut and shiny due to suppuration, while
its color is reddish(fig)

32. Glassy oedematous swelling of eye region of
canine fossa abscess
Extraoral swelling at the
infraorbital region and nasolabial
fold with red shiny skin

33.  Canine space infection
in patient's right side
resulted from infected
canine tooth. The
swelling of nasolabial
and infraorbital areas is
demonstrated.

34. Treatment of Canine Fossa Abscess
1.The incision for drainage is performed intraorally at
the mucobuccal fold (parallel to the alveolar bone), in
the canine region.

35. 2. A hemostat is then inserted, which is placed at the
depth of the purulent accumulation until it comes into
contact with bone, while the index finger of the
nondominant hand palpates the infraorbital margin.

36. 3. Finally, a rubber drain is placed, which is stabilized
with a suture on the mucosa.

37. Buccal Space
Borders:
 Superior: inferior margin of zygomatic arch
 Inferior: Inferior margin of mandible
 Anterior: Corner of the mouth
 Posterior: anterior margin of Masseter muscle
 Interior: Buccinator muscle
Layers:
 Skin
 Superficial fascia
 Buccinator muscle
 Buccal Pad of fats
 Submucous layer
 Mucous membrane

38. Buccal Space Infection
Odontogenic: (most frequently)maxillary and
mandibular posterior teeth.
Nonodontogenic: adenophlegmon of facial lymph
nodes.
Secondary spread of infection:
 Superiorly: pterygopalatine space
 Inferiorly: pterygomandibular space

39. Buccal space lies between
buccinator muscle and
overlying skin and
superficial fascia. This
potential space may
become involved via
maxillary or mandibular
molars

40. Clinical Presentation of Buccal Abscess
 Swelling of the cheek, which extends from the zygomatic
arch as far as the inferior border of the mandible, and
from the anterior border of the ramus to the corner of the
mouth.
 The skin appears taut and red, with or without fluctuation
of the abscess.
 There can be intraoral bulging.

41. This buccal space infection
was result of maxillary molar.
Typical swelling of the cheek
is demonstrated, which does
not extend beyond inferior
border of mandible.

42. Buccal-space
infection with
periorbital
extension
developing from
a nonvital
maxillary molar
tooth

43. Obvious swelling of the right cheek.
Side view. Fluctuant mass extending
toward the buccal side of the gum end
to the gingival-buccal reflection
---Gingiva with swelling and erythema.

44. Treatment of Buccal Space Abscess
Access to the buccal space is usually intraoral for three main
reasons:
1. Because the abscess fluctuates intraorally in the majority of cases.
2. To avoid injuring the facial nerve.
3. For esthetic reasons.
The intraoral incision is made at the posterior region of the
mouth, in an anteroposterior direction and very carefully in
order to avoid injury of the parotid duct. A hemostat is then used
to explore the space thoroughly.
An extraoral incision is made when intraoral access would not
ensure adequate drainage, or when the pus is deep inside the
space. The incision is made approximately 2 cm below and
parallel to the inferior border of the mandible.

45. VIDEO
of Intraoral Incision of buccal
Abscess

46. Submental Space
Borders:
 Lateral: anterior bellies of the right and left Digastric muscles
 Anterior: internal border of corpus of mandible
 Posterior: Hyoid bone
 Roof: Mylohoid muscle
 Lower margin: Skin and Platysma muscle

47. Submental Space Infection
Odontogenic: from frontal teeth of the mandible
Nonodontogenic: adenophlegmon or trauma
Secondary spread: from submandibular or
sublingual spaces

48. Clinical Presentation of submental Abscess
 Edema in submental region which can spread to
submandibular space.
 Palpation is painful and fluctuation is present
 Hyperemia of skin
 Functional disturbances in protrusion of the jaw
 Dysphagia or discomfort while swallowing can be
present.

49. Clinical photograph showing
severe extraoral swelling at the
submental region

50. Submental
Abscess

51. Submental space infection appears as discrete swelling in central
area of sub-mandibular region.

52. Submental space abscess,
secondary to dental disease

53. Treatment of submental Abscess
1. Local anesthesia is performed around the abscess
Peripheral infiltration anesthesia of healthy
tissues surrounding inflammation
Mature submental abscess ready for
incision and drainage.

54. 2. An incision on the skin is made beneath the chin, in
a horizontal direction and parallel to the anterior
border of the chin.
Diagrammatic illustration (a) and clinical photograph (b) showing the incision for
drainage of the abscess.

55.  The pus is then drained in the same way as in the other
cases .
Insertion of a hemostat and exploration
of the abscessed area
Withdrawal of the hemostat from the
cavity with open beaks, facilitating the
evacuation of pus

56.  Rubber drain placed at the drainage site of the
abscess

57. Submandibular Space
Borders:
 Superior: Mylohoid muscle
 Inferior: Skin
 External: inferior border of the body of mandible
 Anterior: Anterior belly of Digastric muscle
 Posterior: Posterior belly of Digastric muscle
Consists of:
 Submandibular salivary glands
 Submandibular lymph nodes
 Facial artery
 Anterior facial vein

58. Submandibular Space Infection
Odontogenic: mandibular molars and premolars
Nonodontogenic:
 Adenophlegmon of submandibular lymph nodes
 Purulent process of submandibular salivary glands
Secondary spread: submental (most frequently) or
sublingual.

59. Clinical Presentation
 The infection presents as moderate swelling at the
submandibular area, which spreads, creating greater
edema that is indurated and redness of the overlying
skin.
 Angle of the mandible is obliterated
 Pain during palpation
 Moderate trismus due to involvement of the medial
pterygoid muscle

60. Clinical photograph showing severe
swelling at the left posterior area of
the mandible

61. This submandibular
space infection
produced large,
indurated swelling of
submandibular
space.

62. Abscesses of the submandibular neck space are common
in children. The treatment is incision and drainage.
Cultures are obtained and the appropriate antibiotic is
administered.

63. Treatment of Submandibular Abscess
1.The incision for drainage is performed on the skin,
approximately 1 cm beneath and parallel to the inferior
border of the mandible. During the incision, the course of
the facial artery and vein (the incision should be made
posterior to these) and the respective branch of the facial
nerve should be taken into consideration.

64. 2. A hemostat is inserted into the cavity of the abscess to explore the
space and an attempt is made to communicate with the infected spaces .

65. 3.After drainage, a rubber drain is placed.
Stabilization of a rubber
drain at the site of incision
Postoperative clinical 
photograph 10 days later

66. The submandibular abscess was incised and drained. It
contained thick, greenish pus. A drain was left in the
wound.

67. Submandibular abscess in an adult with diabetes
mellitus.

68. VIDEOof Incision
of Submandibular Abscess

69. Sublingual Space
Borders:
 Superior: mucous membrane of floor of mouth
 Inferior: Mylohoid muscle
 Posterior: muscles of the tongue and hyoid bone
 Lateral and anterior: inner surface of body of mandible
 Medially: Lingual septum

70. Sublingual Space
Consists of:
 Submandibular duct(Wharton’s duct)
 Sublingual gland
 Sublingual and lingual nerve
 Terminal branches of lingual artery
 Part of submandibular gland
Can be divided into:
 Proper sublingual space
 Mandibular-lingual sulcus
(right & left)

71. Sublingual Space Infection
Odontogenic: mandibular anterior teeth,
premolars, and 1st molars whose apices are found above
the attachment of the Mylohoid muscle.
Nonodontogenic: Sublingual glands infection
Secondary spread from:
 Submandibular
 Submental by ascending way through
fibers of Mylohoid muscle
 Lateral pharyngeal

73. Clinical Presentation
 Firm, painful swelling of mucosa of floor of the
mouth, resulting in elevation of the tongue towards
the palate and backwards
 Pain and difficulty swallowing (Dysphagia)
 Movement of the tongue is painful
 Mandibular-lingual sulcus is obliterated and mucosa
presents a bluish tinge
 Moderate or no external swelling
 The patient speaks with difficulty, because of the
edema, and movements of the tongue are painful.

74. B- This isolated sublingual space infection
produced unilateral swelling of floor of
mouth.
A-Sublingual space
between oral mucosa and
Mylohoid muscle.

75. Swelling of the mucosa of the
mouth floor and characteristic
elevation of the tongue towards
the opposite side
Abscess in the sublingual space 
due to infection of Wharton's duct
infection

76. Extension of
sublingual abscess to
the submandibular
space.

77. Treatment of Sublingual Abscess
1.The incision for drainage is performed intraorally,
laterally, and along Wharton’s duct and the lingual
nerve

78. 2.In order to locate the pus, a hemostat is used to
explore the space inferiorly, in an anteroposterior
direction and beneath the gland.

79. 3.After drainage is complete, a rubber drain is placed.

80. Pterygomandibular Space
Borders:
 External : anterior margin of ramus of mandible
 Internal: external surface of lateral pterygoid muscle
 Superior: medial pterygoid muscle
 Posterior: partially by parotid gland and styloglossus muscle
 Anterior: Buccinator muscle
Consists of:
 mandibular neurovascular bundle
 Lingual nerve
 part of the buccal fat pad

81. Pterygomandibular Space Infection
Odontogenic:
 3rd molar pericoronitis
 Apical infection of molars
Nonodontogenic:
 Hematoma
 Septic mandibular Nerve block----
 Fracture of the jaw
Secondary Spread:
 infratemporal
 Submandibular
 lateral pharyngeal spaces.

82. Clinical Presentation of
Pterygomandibular Abscess
 Severe trismus and slight extraoral edema beneath the
angle of the mandible are observed
 Tenderness and pain on deep palpation over medial
aspect of ramus
 Intraorally:
 edema of the soft palate of the affected side is present
 displacement of the uvula and lateral pharyngeal wall
 There is difficulty in swallowing.

83. Treatment of Pterygomandibular
Abscess
1.The incision for drainage is
performed on the mucosa
of the oral cavity and, more
specifically, along the
mesial temporal crest. The
incision must be 1.5 cm
long and 3–4 mm deep.

84. 2.A curved hemostat is then inserted, which proceeds
posteriorly and laterally until it comes into contact
with the medial surface of the ramus.
3.The abscess is drained, permitting the evacuation of
pus along the shaft of the instrument.

85. To Be Continued……

87. Cellulitis: initial stage of infection
 Diffuse, reddened, soft or hard
swelling that is tender to
palpation.
 Inflammatory response not yet
forming a true abscess.
 Microorganisms have just
begun to overcome host
defenses and spread beyond
tissue planes.

88. True abscess formation
 As inflammatory response
matures, may develop a
focal accumulation of pus.
 May have spontaneous
drainage intraorally or
extraorally.