Endodontics DB 305C Module 1 Year 3. Wan Noorina WA
¡ Explain the scope of endodontic treatment ¡ Explain why root canal treament needs to be carried out
¡ Describe the stages of root canal treatment ¡ Describe the standards of treatment ¡ List the factors that determine the success of treatment
¡ Characterize aetiological factors causing pulpal inflammation
¡ Explain the mechanism of spread of inflammation in the pulp and periradicular tissues and its consequences
¡ Explain why the pulp has difficulty in recovering from severe injury
¡ Classify the pulpal and periradicular lesions ¡ Describe the step involve in healing(resolution) of
periradicular lesions following successful root canal treatment
¡ Identify in general, non-‐endodontic lesions that may simulate endodontic periradicular lesions
¡ The study of form, function and health of:-‐
¡ Injuries to and diseases of dental pulp and periradicular region
¡ The prevention ¡ The treatment management
¡ The clinical management that consists of procedures that are design to maintain the health of all or part of dental pulp
¡ When pulp is diseased or injured, treatment aimed at preserving the normal periradicular tissues
¡ When infection pursues, treatment is aimed at restoring the periradicular tissues to health
¡ This is done with root canal treatment, + surgical endodontics
Healthy pulp
Inflamed
Pulpectomy Root canal treatment (Preserving The Normal Periradicular Tissues)
Maintain health
Infected
Pulp capping Pulpotomy
Root canal treatment Root canal re-‐treatment Apical surgery (Restoring The Periradicular Tissues To Health)
WHY?
¡ Living organisms § Micro-‐organisms ▪ Bacteria ▪ Viruses ▪ ? Others
¡ Non-‐living irritants § Mechanical § Thermal § Chemical
¡ Kakehashi et al. The effects of surgical exposures of dental pulps in germ-‐free and conventional laboratory rats. Oral Surg Oral Med Oral Pathol 20:340; 1965
¡ Moller et al. Influence on periapical tissues of indigenous oral bacteria and necrotic pulp tissue in monkeys. Scant J Dent Res 89:475, 1981
¡ Microorganisms § Toxins § By products
¡ Pulp is infiltrated at the base of the carious tubules by
§ Chronic inflammatory cells § Macrophages, lymphocytes § Plasma cells
¡ Once pulp is exposed, pulp is infiltrated by PMN to form liquefaction area at the site of exposure
¡ Bacteria colonize and
persist at the site
¡ Pulp tissue will § Remain inflamed for a long
time or § Undergo necrosis slowly or
rapidly ¡ Depending on
§ Bacteria virulence § Ability to release
inflammatory fluids § Host § The amount of circulation § Lymph drainage
¡ By this time pulp harbors bacteria and by-‐products.
¡ Pulp can only defend temporarily to impede the spread of infection and tissue destruction
¡ More irritantàmore damage and will spread throughout pulp
¡ Subsequently bac, toxins & by-‐products will diffuse periapicallyàapical inflammatory lesions
¡ Where is the bacteria?
§ Cavity prep (physical) § Cavity prep without water (physical with thermal) § Physical pressure on the prepared tooth (physical) § Deep periodontal curettage (physical) § Occlusal trauma (physical) § Orthodontic movement (physical) § Dentine expose § Dental materials ▪ Restorative materials ▪ Cements
IEJ 42, 422-‐444, 2009
Chemical irritants? Leakage?
¡ Mixed pulpal response to Dycal after 3 months. CP (restorative material along with Dycal) C: Distinct but incomplete hard tissue bridge (BR), revealing gaps on either side of BR with infiltrate of chronic inflammatory cells
¡ Who can survive after an injury? ¡ Type of injury
¡ The condition of the pulp ¡ Tissue involve
§ Pulp tissue
¡ Initial response § Hard tissue formation § Examples? § How?
¡ Moderate to severe response § Inflammatory process § Non specific inflammatory mediators and specific immune reactions
¡ Direct irritation § Hyper-‐occlusion § Occlusal trauma § Endodontic procedural accidents
§ Overinstrumentation § Overextention of GP ▪ Physical ▪ Chemical
¡ Bacteria?
31 Jan 2005 16 Apr 2005
25 June 2005
¡ Healing § Regeneration § Repair
¡ How can you tell? ¡ The aim of RCT is to
remove the irritant within the canal
¡ Healing by repair will take place once the irritant is removed and ‘inflammation’ process for healing will take its course
¡ Immune system will take
its course
¡ Osteoclastic resorption stops resorbing bone.
¡ In healing process,
osteoblast cells will start depositing new bone and deposit new matrix.
REGENERATION OR REPAIR?
¡ Normal pulp, Healthy pulp ¡ Reversible pulpitis
§ Symptoms § Treatment
¡ Irreversible pulpitis § Symptoms? Asymptomatic? § Signs-‐ PA? § Treatment § Hyperplastic pulpitis ▪ Chronically inflamed young pulp
¡ Pulp calcification ¡ Internal resorption
§ Lectures in Year 4
¡ Pulpal necrosis § Symptoms § Test & treatment § Not responsive § PA radiographs= normal
¡ Normal Periapical tissues ¡ Apical periodontitis
§ Acute ▪ Moderate to severe pain ▪ Tender to palpation ▪ Excruciatingly painful to
percussion ▪ May or may not respond to EPT ▪ PA-‐ Slight widening of lamina
dura § Chronic apical periodontitis ▪ May not be in severe pain ▪ Tender to palpation ▪ Tender to percussion ▪ Not responsive to EPT ▪ PA-‐ apical radiolucency
¡ Apical abscess § Acute apical abscess § Rapid onset, painful § No swelling if confined to
bone, otherwise swelling is positive as collection of pus seeps through path of least resistance: soft tissue
§ Tender to palpation and percussion
§ PA-‐ no lesion, + ve widening, and obvious
§ Chronic abscess ▪ Presented with sinus tract ▪ + PA radiolucency
ACUTE APICAL PERIODONTITIS
46
¡ CHRONIC APICAL PERIODONTITIS
¡ Acute apical abscess
¡ Chronic Apical Abscess
¡ Very similar to odontogenic lesions
¡ Must be vigilant ¡ Use tests to guide
§ Clinical findings § Sensibility testing § PA radiographs
¡ Usually response to EPTs
¡ Normal structures ¡ Non odontogenic diseases § Early stage of monostotic fibro dysplasia
§ Ossifying fibroma § Dentigerous cysts § Central giant cell granuloma
Ameloblastoma
Periapical cemento-‐osseous dysplasia
¡ Harty’s, Endodontics in Clinical Practice, BS Chong 2010
¡ Endodontics Principles and Practice T and Walton
Questions?