Endodontic Microbiology, Diagnosis, Radiology

• Welcome to laboratory endodontics at UNINASSAU, 5th period-2025.1
• The lectures are taught by Dr. Ruth Ricardo, a dental surgeon from UFPE and an endodontics specialist from CPGO.
• Lecture 2 covers endodontic microbiology, endodontic diagnosis, and radiology in endodontics.

Routes of Infection

• The main portals of entry for infections of the dental pulp are through dentinal tubules, direct pulpal exposure, periodontal disease, and anachoresis.

Periodontal Disease

• Degenerative and inflammatory changes of varying degrees can occur in the pulp of teeth with related periodontal disease
• Pulpal necrosis due to periodontal disease only occurs if the periodontal pocket reaches the apical foramen.

Anachoresis

• Anachoresis is the process where microorganisms are transported via blood or lymph, leave the vessel, invade tissues, and cause an infection.

Types of Endodontic Infections

• Endodontic infections are localized as either intra-radicular or extra-radicular
• Intra-radicular infections are located inside the root canal system.
• Extra-radicular infections exist outside the root canal system.
• Microorganisms involved in endodontic infections can be categorized by when they colonize the root canal:
• Primary intra-radicular infections are caused by microorganisms involved in the initial invasion of the dental pulp, leading to inflammation and subsequent necrosis.
• Secondary intra-radicular infections are caused by microorganisms not present in the primary infection but introduced into the root canal during or after professional intervention.
• Persistent intra-radicular infections are caused by microorganisms from a primary or secondary infection that resist intracanal antimicrobial procedures and survive nutrient deprivation in the prepared canal.

Primary Intra-radicular Infection

• Involves microorganisms in the pulpal invasion, which results in inflammation and later necrosis.
• Involves microorganisms taking advantage of the favorable environmental conditions of the canal after pulpal necrosis.
• Involves facultative and strict anaerobic bacteria.

Secondary Intra-radicular Infection

• Pertains to MO that were not already present in the primary infection; rather, were introduced into the root canal system during some point following a professional intervention.
• Occurs during treatment, in between consultations, or even after root canal obturation.

Persistent Intra-radicular Infection

• A MO from either the primary or secondary infection has become resistant to the intra canal procedures and can withstand periods of nutrient deprivation.

Extra-radicular Infections

• Can be either dependent or independent from the primary.
• Is most times related to having an intra-radicular infection
• An independent extra-radicular infection is actinomycosis and is treated with surgery

Extra-radicular Infection Dependent on Intra-radicular Infection

• MO coming from the root canal invades and then proliferates in the surrounding tissues.
• Biofilms can adhere to the outer most surface of the root.
• Symptoms include an apical abscess. Treatment and well managed with endodontic treatment.
• Asymptomatic includes apical periodontitis with no symptoms. Managed well with non-surgical endodontic retreatment

Symptomatic Infections

• The occurrence and intensity of symptoms depends on several factors:
• The number of bacterial cells
• The virulence of the bacterial strains
• The number of species and how they interact creating or resulting in a pathogenic effect
• Host resistance

Microbial Colonization Patterns

• Involve 1° facultative bacteria
• Involve 2° strict anaerobic bacteria
• Involve planktonic cells that are suspended in fluid during treatment, can be easily managed
• The can be biofilms propagating through or along dentinal tubules, canals, and isthmuses. These are hard to eliminate and manage and needs therapeutic intervention

Microbiota in Endodontically Treated Teeth

• The microbiota typically includes bacterial species.
• E. faecalis
• C. albicans
• Anaerobic species

Irritating Agents

• Irritation of the pulpal or periapical tissues can result in inflammation.
• The extent of the inflammation is proportional to the damage intensity and severity of the tissues
  • Living irritants inclue: Microbes and viruses.
  • Non-Living irritants include: Thermal, Chemical and Mechanical.

Pulpal and Periapical Pathologies

• Pulpal pathologies include reversible pulpitis, irreversible symptomatic pulpitis, hyperplastic pulpitis, and pulpal necrosis.
• Periapical pathologies include acute apical periodontitis (symptomatic), chronic apical periodontitis (asymptomatic), acute and chronic apical abscesses, and condensing osteitis.

Reversible Pulpitis

• Is a mild inflammation that when causes are removed, inflammation will then be reversed making the pulp to regain its normal state
• Symptoms include: being asymptomatic and light pain
• Treatment includes an exposed dentin restauration with irritation removal.

Irreversible Symptomatic Pulpitis

• It is a severed inflammatory process that no longer is effective, due to the cause no longer happening
• Symptoms include continues, and sometimes moderate to intense pain. The pain can be anywhere and hard to locate
• Patients react extremely when thermal treatments occur. Percussion can happen or not happen depending on the pain

Hyperplastic Pulpitis (Pulp Polyp)

• Is irreversible pulpitis commonly seen in young patients
• Symptoms and signs: Generally asymptomatic, overgrowth, lesion inside the caries
• Treatment: Root canals or removing and cutting the pulpal areas

Pulpal Necrosis

• Classified as either liquefaction necrosis or ischemic necrosis.
• Liquefaction is from irreversible pulpitis, ischemic is from trauma.
• The symptoms: Can be asymptomatic but at times discomfort can arise with pain or periapex tenderness
• Tests show the application of cold or hot stimuli do not have any response
• Treated with non-surgical endodontic treatment

Periapical Pathologies

• Periapical changes can occur after pulpal necrosis. Reactions are complex, involving inflammatory mediators and specific immune reactions.
• Bone reabsorption creates irritation with the bone and preventing infection
• Severity depends on the extent of the response which can vary from inflammation to complete tissue destruction

Symptomatic Apical Periodontitis

• Etiology: Is pulpitis extension that has already been damaged. Also due to excessive amounts of solution and premature or early contacts with the tooth.
• Symptoms include spontanous discomfort which has been determined at as moderate to sever.
• Pain during the mastication process

Asymptomatic Apical Periodontitis

• Mostly occurs when a pulp is dead or has undergone pulpitis
• Signs and Symtoms: Clinically there is no existing symptom besides the destruction of the periapical tissues.

Acute Dentoalveolar Abscess

• Created from a liquefactive or diffused pulpal damage. It also represents an exaggerated immune response.
• Symptoms and signs include fever, white blood cell count and overall weakness
• This can be found and seen quickly with a growth appearance as well as constant pain.

Tests for Acute Dentoalveolar Abcess

• The pain is very hard to tolerate. Non responsive tissue
• Not much can be seen depending on radiograph

Treatment for Acute Dentoalveolar Abscess

• Draining is possible with root canal treatment

Chronic Dentoalveolar Abscess

• Lesions created from the root pulp for an extended time and is described by lesions in the surfaces.
• Asymptomatic

Symptoms and Signs for Chronic Dentoalveolar Abscess

• An opening that leads to other areas of the area.

Tests for Chronic Dentoalveolar Abscess

• Tenderness will be at a low state. Cortical sides may swell.

Treatment for Chronic Dentoalveolar Abscesss

• Managing the pulp with endodontics.

Condensing Osteitis

• A form of periodontitis that lacks any symptoms. With a constant increase in trabecular area in response to irritation. Most commonly found at the apexes and most commonly are related to the pulp or teeth.
• Based on the cause, the condensing can be completely asymptomatic or have pain

Tests done for Condensing Osteitis

• Pulp tissue will only react to certain stimuli
• Depending on area, teeth may be sensitive to touch

Treatments for Condensing Osteitis

• Root canals

Repair Processes

• This diminishes inflammation that causes proliferation
• Osso forms to replace areas that have been reabsorbed

Differential Diagnosis

• Normal structures include bone medullary spaces near tooth apices, submandibular fossa, maxillary sinus, apical papilla of developing teeth, mental foramen, and lingual depressions in the jaw.
• Associated teeth test positively for pulp vitality and show no clinical signs or symptoms.
• Radiolucent lesions can be moved relatively with an X-ray.

Benign Non-Endodontic Pathologies

• Initial stages include cemental dysplasia, ostein, simple marrow cyst, giant cell granulomas, hyperthyroidism and ameloblastomas.
• Radiographically the is not damaged.
• Diagnosis comes for a histological view of bone structure.

Non-endodontic Malignant Pathologies

• Metastatic lesions commonly includes lymphomas and sarcomas Different from this is pulp vitality and extensive destruction of the tissues.
• Pulp vitality is important because it can cause the tissue to respond at a slower rate, thus having a negative effect.

Diagnosis in Endodontics

• Diagnosis is recognizing through all the signs and symptoms.
• Basic steps through the diagnostic process:
• Medical history
• Chief complaint
• Clinical examination
• Radiographic examination
• Diagnosis
• Treatment plan

Chief Complaint

• This refers to the pain that patient is undergoing currently:
• Provoked or spontaneous?
• Continuous or pulsing?
• Short or long amounts of pain?
• Localized pain

Clinical Exam

• This involves teeth and tissues
• This also involves mirrors and explorers

Tests include

• Cold
• Electric Testing