1. Introduction to
ODONTOGENIC INFECTIONS OF
THE HEAD AND NECK
Dr V.RAMKUMAR
CONSULTANT
DENTAL&FACIOMAXILLARY SURGEON
REG NO:4118 .TAMILNADU-INDAI(ASIA)
2. INTRODUCTION
• “Intact dentition, periodontal structures and oral mucous
membrane constitutes the first line of resistance within
the oral cavity against the invasion of microorganisms.
Once microorganisms begins to DOMINATE over the
host response INFECTION sets in.”
• They are classified in to:
– Acute: Rapid onset
– Chronic: Prolonged duration
3. PRINCIPLES RELEVANT TO
SPREAD OF INFECTION
• Spread of infection within the dental structures:
Dental caries
Pulp
Periapical tissue
(Least resistance)
(inflammatory changes in the
pulp)
(multiplication of
microorganisms)
Beyond periapical region
4. SPREAD OF INFECTIONS FROM BONES
• Pathway
Periapical region
Alveolar bone
Central marrow space
Cortical plate
Perialveolar soft tissue
Muscle plane
5. GENERAL FACTORS INFLUENCING
THE SPREAD OF INFECTION
1. State of the oral microorganism
2. Host and its environment
3. Disturbance to the delicate balance between the oral
micro flora and a host resistance
4. Anatomical consideration
6. STATE OF THE ORAL MICROORGANISM
1. Change in the oral environment
Results in the multiplication of microorganisms in large
numbers, which may resist the virulence factors.
2. Virulence
Refers to the quality of microbes that is harmful to the
host.
3. Mediators
Release toxins like hyaluronidase which may aid in the
spread of infection.
7. HOST AND ITS ENVIRONMENT
• Resistance varies between:
– Individuals
– Time in some individuals
– Age
– Sex
– Debilitating conditions (diabetes, malnutrition, chronic
nephritis, hepatitis, AIDS and immunity status of the
hosts) are directly related to onset and spread of
infection
8. DISTURBANCES BETWEEN ORAL
MICROFLORA AND HOST RESISTANCE
• The resistance factors of the host can be
considered under:
– Local defense: Integrity of the primary line of defense
like intact teeth, periodontal structures and oral
mucosa in the salivary environment with efficient
drainage system. Any alteration leads to penetration
of microbes across the primary barrier.
– Humoral and cellular defense
9. LOCAL FACTORS GOVERNING THE
SPREAD OF INFECTION
1. Alveolar bone – Represents the first locally limiting
barrier to the further spread of a periapical infection
2. Periosteum – The next limiting barrier, which can delay
the further spread of infection
3. Anatomic arrangement of the adjacent muscles and
fascia – Which determines the next possible site of
localization.
ps: All these represent only relative barriers and that ultimately
the capacity of the host’s defensive mechanism still governs
the final extent of spread
10. DIAGNOSIS OF ODONTOGENIC
INFECTION
• Clinically there are three stages in the progression of
odontogenic infection.
1. Periapical osteitis
2. Cellulitis
3. Abscess
ps: Each tooth has a specific anatomic site(s) of primary
localization. From the location of the swelling it is possible to
predict the tooth or teeth involved in the infectious process.
Thus a knowledge of the various anatomic spaces is
essential.
11. ANATOMICAL CONSIDERATIONS
• Tissues of the head and neck are invested in fascial
planes separated by loose connective tissues
• Fascial planes tend to localize the infection within their
limits
• These planes communicate with each other
• Pus traces along the path of least resistance and
penetrates the various fascial planes, blood vessels and
lymphatics.
15. THANK YOU
To be continued in next class
Each space infection in detail
Ludwig’s Angina
Principles of management & Treatment of
Odontogenic Space Infections
