Endodontic Treatment Rationale & Clinical Skills

Treatment Rationale

• Residency in endodontics includes literature reviews and clinical skill development
• Clinical skill development includes completing 300 cases
• Endodontic programs train residents, where 10 residents from 3 classes received the same training from two board-certified endodontists
• Continuing education (CE) attendance and practice are essential

Clinical Treatment

• Restorability of a tooth is determined by the dentist and faculty, not the endodontist
• Root canal treatment (RCT) can be performed on any tooth when deemed necessary
• Posts are used to retain the core structure of a tooth

Level of Experience

• An average of six completed cases per student has been consistent since 1975

Instruction Philosophy: "Classic" Endodontic Training

• Classic endodontic training involves stainless steel hand files, such as K-files and Hedstrom files
• K-files are used with a quarter-turn-and-pull motion, not like a corkscrew
• Hedstrom files are used with a pull motion
• Cold lateral compaction obturation and NaOCl irrigation are components of classic training

Instruction Philosophy: "Modern" Endodontic Training

• Modern training uses nickel-titanium (NiTi) rotary instrumentation, which has a risk of breakage
• Warm vertical compaction is utilized
• Adjuncts include EDTA, activation of irrigants with sonic devices to break up debris, and CBCT imaging

Transition to the Clinic

• The clinic refines the art and science of dentistry
• Interviewing patients elicits useful information to aid diagnosis

Transition to Patient Care

• Transitioning from preclinical/lab work to patient care is significant
• Key factors include the patient's medical status, diagnosis, prognosis, informed consent, variations in tooth anatomy and choice of appropriate anesthesia and technique

Patient Management

• Patient management includes bathroom breaks, bite blocks, and dental dams that expose the nose
• Procedures may require multiple visits, often two to three times

Treatment Verification Steps

• A thorough process includes reviewing medical history, radiographs, and testing, as well as establishing a diagnosis, prognosis, and informed consent
• Further steps: administering anesthesia, isolation, access, canal identification, electronic apex locator (EAL) use, glide path evaluation, orifice opening and recapitulation with a 10K file to remove dentinal shavings
• Create an estimated working length radiograph, crown-down NiTi rotary shaping, master cone radiograph, obturation evaluation, interim restoration, and final radiograph

Rationale to Refer

• General dentists complete 80% of RCTs
• The term "easy endo" is a misnomer
• Key factors are difficulty being optimistic, patient management, and long-term prognosis

Clinical Protocol

• Medical history review helps avoid treating strangers
• Chief complaints should be directly quoted, for example "My front tooth hurts"
• Pain should be rated on a 0-10 VAS (visual analog scale)
• Patients should point to the area of concern

Radiographs

• Radiographs should be taken on the same day if there's any change to the tooth since the last visit or within one month of initial assessment at LMU CDM
• Take straight on shot and shift periapical with 2 mm past apex, bitewing (BW) with alveolar crest visible

Additional Sensitivity Testing

• Includes transillumination and electric pulp testing (EPT)

Water Bath

• Used for thermal testing with cold (from refrigerator) or hot (microwave) water
• The temperature must be verified with a thermometer

Clinical Protocol: Clinical Photographs

• Clinical photographs should be taken
• Soft tissue findings may include a parulis, which is a bump from a chronic abscess, or swelling that can be intraoral or extraoral

Clinical Protocol: Tooth

• Assess the presence of cracks and the quantity of remaining tooth structure

Pulpal Diagnosis

• Includes normal pulp, reversible pulpitis, symptomatic/asymptomatic irreversible pulpitis, pulp necrosis, previously initiated therapy or treatment, or normal periapical tissue
• Includes also symptomatic/asymptomatic apical periodontitis, chronic/acute apical abscess, and condensing osteitis

Layman’s Prognosis

• Prognosis can be categorized as excellent, good, fair, poor, or hopeless, and described as favorable or unfavorable

General Prognosis

• A vital tooth has a 90-95% chance of healing
• A non-vital tooth with a lesion has an 80-85% chance of healing

Retreatment Prognosis

• Retreatment without a lesion has a 70-90% chance of healing
• Retreatment with a lesion has a 70-75% chance of healing

Apicoectomy Prognosis

• Apicoectomy with retreatment has a 90% chance of healing
• Apicoectomy without retreatment has a 50% chance of healing

Layman's terms: Root Canal

• Root canal in patient-friendly terms involves cleaning the inside of the tooth and putting a filling material inside the tooth that looks like rubber

Layman's terms: PARL

• PeriApical Radiolucency (PARL) means a dark area in the bone
• A PARL is usually nothing bad, but a defect in the bone or breakdown usually caused by the infection
• A PARL can be a granuloma, or wet scab, or could be a cyst
• A PARL can heal with RCT, biopsy is usually not necessary
• Takes 6 months to a year to observe improvement on a radiograph, rarely other type of pathology

Case Presentation Summary

• Case presentation includes a summary of medical history, sensitivity test results, diagnosis, proposed treatment, and anticipated challenges

Nitrous Oxide

• Using non-technical language like "clean the inside" can be less scary
• Nitrous oxide can help reduce blood pressure
• Nitrous oxide can aid to anesthesia

Clinical Treatment

• Preparation and organization reduce stress levels
• Chaos increases a patient's stress and reduces their confidence

Anesthesia: Topical Anesthetics

• Potential allergens, dye, and sweeteners present concerns
• Benzocaine is a topical anesthetic concern
• Methemoglobinemia is a rare but potentially severe consequence of topical anesthetics and is a medical emergency

Anesthesia: Lollicaine

• Lollicaine, which is benzocaine, is generally well-tolerated and non-toxic.
• OTC oral drug products with benzocaine should not be used in infants and children younger than 2 years
• These oral drug products with benzocaine should be used with caution on adults and children 2 years and older

Anesthesia: Initial Anesthetic

• 2% Lidocaine with 1:100,000 epinephrine is a safe choice for initial anesthesia
• Readministration for pulpal anesthesia is common in this setting

Anesthesia: Secondary Anesthetics

• 4% Articaine (Septocaine) is used for buccal infiltration under supervision due to the risk of paresthesia
• 3% Mepivacaine (Carbocaine) has no epinephrine and is Class C for pregnancy
• 0.5% Bupivacaine (Marcaine) with 1:200k epinephrine is used for very symptomatic patients

Anesthesia: Cold Test

• Cold testing should confirm profound anesthesia before proceeding

Anesthesia: Pregnancy

• The FDA drug classification system is based on risks to pregnant women and their fetuses
• Lidocaine is considered safe in Category B
• Mepivacaine and Bupivacaine are Category C and used with caution
• During the first trimester and lactation, local anesthesia WITHOUT a vasoconstrictor is preferred

Anesthesia: Vasoconstrictors

• Potential reactions in the fetus and neonate are not due to the vasoconstrictor but to the preservative, so that preservative is to be avoided with vasoconstrictors for pregnant women
• Prilocaine is contraindicated due to the risk of the fetus developing methemoglobinemia

Pulpal Anesthesia

• Pulpal anesthesia onset takes 10-30 minutes normally
• Inflamed teeth may only have a 25-40% success on the MN posterior with an IANB

Adjunct Local Anesthetic Techniques

• Intraligamentary injections use 2% Lidocaine and 3% Mepivacaine
• No Articaine or Bupivacaine is used in intraligamentary injections

Intraosseous Injection

• Intraosseous injections have a 70-90% chance to achieve profound anesthesia
• Heat generation can cause necrosis of soft and hard tissue, or cause alveolus separation
• A separated alveolus needs to have the port carefully removed

Pulpal Anesthesia Duration for Lido 2%

• About 60 minutes, non-inflamed

Pulpal Anesthesia Duration for Marcaine

• Bupivacaine 0.5% can last up to 6 hours

Pulpal Anesthesia Duration for Carbocaine

• Mepivacaine 3% lasts 20-40 minutes

Pulpal Anesthesia Duration for Septocaine

• Articaine lasts about 60 minutes, non-inflamed

Isolation

• Isolation typically involves a single tooth
• Once a tooth is accessed, the rubber dam remains until access is sealed
• Only the frame is removed for radiographs

Access

• Do NOT blow air once access has started, to avoid air embolism
• Use 557, 245 bur for efficient removal of decay, restoration, and necessary tooth structure
• Switch to a low-speed round bur to refine access
• Caries removal leads to sound tooth structure and often locates chamber/canals

Access: Amalgam Removal

• Amalgam removal proceeds to sound tooth structure
• Avoid forcing amalgam into entering canals
• Interim restoration to seal against NaOCl leakage and saliva may be necessary before the canal is entered

Endo Z bur

• The Endo Z bur is used after the chamber is located
• It does not have a cutting top so is safe to use

Radiographs

• Radiographs should be frequently taken to evaluate and assess treatment progress
• Stop if you are unsure about anything

Cleaning and Shaping

• The endodontist's secret is that there is no magic file system
• Irrigation includes NaOCI, saline, chlorhexidine gluconate, and EDTA

Irrigation

• Done with constant motion
• Use slow flow rate and move the irrigant up, down, up, down
• Avoid engaging the tip in the canal
• Risks include extrusion out the apex and fracture of the irrigation tip

Length Determination

• Accessed teeth, used EAL and radiograph to establish working length, cemented file with GI, extracted teeth to evaluate accuracy
• The trend is to be longer than assessed; it is better to be short than long

Two-Step Protocol

• Place CaOH in the canal with a file but not metal tip to avoid extrusion beyond the apex
• Medicate the chamber/canal between appointments for 7-10 days
• Use sterile foam or Teflon tape as a spacer in the chamber

Obturation

• Coat gutta-percha with sealer and insert into canal, but do not pump
• The goal is to avoid extrusion of sealer beyond the apex
• Gutta-percha 1mm from the radiographic apex is realistic

Obturation: Gutta Percha Points

• Gutta-percha points are inconsistent from their stated size, so use a gutta-percha gauge
• Carrier-based obturation is not recommended
• Gutta-percha is often stripped off the plastic carrier, which leads to deficient obturation and creates a challenge for retreatment

Interim Restoration

• Glass Ionomer seals well
• IRM (intermediate restorative material) needs a mechanical lock
• Duotemp is similar to GI, but light cure
• Cavit seals well, but for short term use only
• Composite is uncommon

Advanced Endodontic Techniques

• In endodontic residency includes retreatment, second molar endo, post removal, separated file management, apicoectomy, microscope use, perforation repair, intraosseous injections and activation of irrigants
• Use sonic/ultrasonic devices in conjunction with a rationale notebook

Practice Philosophy

• Experience in the clinic will help you develop you own practice philosophy
• The clinical experience will be supported by evidence based rationale

Clinical Competency

• All steps need to be completed without assistance as a standard following graduation
• After passing endodontic competency, all steps are still verified by supervising staff

Cracked Tooth

• Use a tooth slooth for diagnosis and treatment
• Cracked teeth are typically not visible on radiographs and CBCT
• CBCT is used to evaluate for osseous defect
• May take multiple visits/exams to locate