Introduction to

ODONTOGENIC INFECTIONS OF THE HEAD AND NECK

Dr V.RAMKUMARCONSULTANT DENTAL&FACIOMAXILLARY SURGEONREG NO:4118 .TAMILNADU-INDAI(ASIA)

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

PRINCIPLES RELEVANT TO

SPREAD OF INFECTION • Spread of infection within the dental structures:

Dental caries

Pulp

Periapical tissue

Beyond periapical region

(Least resistance)

(inflammatory changes in the pulp)

(multiplication of microorganisms)

SPREAD OF INFECTIONS FROM BONES

• PathwayPeriapical region

Alveolar bone

Central marrow space

Cortical plate

Perialveolar soft tissue

Muscle plane

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

STATE OF THE ORAL MICROORGANISM

1. Change in the oral environmentResults in the multiplication of microorganisms in large numbers, which may resist the virulence factors.

2. VirulenceRefers to the quality of microbes that is harmful to the host.

3. MediatorsRelease toxins like hyaluronidase which may aid in the spread of infection.

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

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

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

DIAGNOSIS OF ODONTOGENIC INFECTION

• Clinically there are three stages in the progression of odontogenic infection.

1. Periapical osteitis2. Cellulitis3. 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.

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.

COMMON MUSCLES INFLUENCING THE SPREAD OF INFECTIONS

• Buccinator• Mylohyoid

• Muscles of mastication

POTENTIAL SPACES INVOLVED IN ODONTOGENIC HEAD AND NECK

INFECTIONS

• Primary Maxillary Spaces– Canine – Buccal – Infratemporal

• Primary Mandibular Spaces– Submental– Buccal– Submandibular– Sublingual

Contd.,

• Secondary Fascial Spaces– Massetric– Pterygomandibular– Superficial and deep temporal– Lateral pharyngeal– Retropharyngeal– Prevertebral

THANK YOU

To be continued in next classEach space infection in detail

Ludwig’s Angina

Principles of management & Treatment of Odontogenic Space Infections