ENDO-PRELIMS PDF - Endodontics Past Paper

DR. Sheikha Ismael ENDODONTICS Main Structures of the Chamber: Roof - location: CEJ or cervical 3rd of the crown - color: yellowish - dentin map: absent - texture: r...

DR. Sheikha Ismael ENDODONTICS Main Structures of the Chamber: Roof - location: CEJ or cervical 3rd of the crown - color: yellowish - dentin map: absent - texture: rough / irregular - signs that u are near the roof: → pinkish - if vital tooth → white yellow / white / pale yellow - non vital (due to thin layer of dentin) Walls Floor - The chamber is getting bigger as furcal area lowers down towards the apical area = hard to do the procedure - it will show large pulp chamber, short root canals due to exceedingly short roots Orifce Root Canal Configuration Type 1 → 1 1 - one canal extends from the pulp chamber to the apex Type 2 → 2 1 - two separate canals leave the pulp chamber and join short of the apex to form one canal Type 3 → 1 2 1 - one canal leaves pulp chamber and divide into two in the roots that merge to exit in one canal Type 4 → 2 2 - one canal leaves the pulp chamber and divides short of the apex into two separate distinct canals with separate apical foramen Type 5 → 1 2 - one canal leaves the pulp chamber & divides short of the apex into two separate distinct canals with separate apical foramen Type 6 → 2 1 2 - two canal leaves the pulp chamber and merge in the body of the root and redivide short of the apex to exit as two distinct canals Type 7 → 1 2 1 2  DR. Sheikha Ismael ENDODONTICS · - one canal leaves the pulp chamber & divides then One rejoin in the body of the root and finally redivides canal / one foramen- 48% into two · Two canals / one foramina- 27% distinct canals short of apex · Two canals / two foramina- 24% Type 8 → 3 3 - three canals down to the apex · Three canals- 1% Individual Teeth First Molar - Average length Central incisor - Average length: → Maxillary: 20.8 mm → Maxillary: 18 - 22.5 mm → mand: 21 mm → mand: 20.7 mm - Morphology: Usually 3 rooted with 3-4 canals. - Morphology: Type I - Palatal canal often curves to buccal in apical third. - Canal is slightly triangular at the cervical area, - Second MB canal usually located between the gradually becoming round in the apical area, - primary Root may have a slight distal and lingual - MB canal and the palatal curvature. - root (1,8 mm) and may exit 2 mm from the root end. - Access: triangular lingual access just above Primary MB canal is the straighter canal. cingulum. - Access: Trapezoidal to facilitate locating MB2. - Lingual shoulder may prevent direct access; watch for calcific metamorphosis post trauma. Second Molar - Average length Lateral Incisor → Maxillary: 20 mm - Average length → mand: 19.8 mm → Maxillary: 22mm - Morphology: usually 3 rooted with 3 canals but can → mand: 20.7 mm exhibit a 4th canal. Three orifices may be - Morphology: Type 1 configured in a straight line. - Canal is ovoid in the cervical area and round in the - Access: quadrilateral to locate 4th canal. apical area - Root apex commonly has a distal dilaceration. - Access: triangular to ovoid. CONCLUSION: - Beware of dilacerations; watch for dens in dente. - The keyword in understanding root canal Canine morphology is variation. - Once we know the Variations, we can fully grasp - Average length and appreciate the internal anatomy of the root → Maxillary: 26.5 mm canal as an important tool in Endodontic Diagnosis, → mand: 25.6 Treatment and Prognosis. mm - Morphology: Type I - Canal is ovoid in shape. ACCESS CAVITY PREPARATION - Root can curve in any direction in the apical third, but is usually to buccal Cavity prepared on the crown of the tooth for the endodontic - Apical foramen frequently not located at anatomic instruments and materials to gain direct path to the apex, apex. for - Access: ovoid above cingulum biomechanical preparation and obturation - Beware of buccal apical dilaceration o Initial prep o Caries is removed bc of pre-tx First Premolar o We open up the tooth to be accessible until the - Average length apex → Maxillary: 20.6 mm Specific Objectives → mand: 21.6 mm 1. To know the principles and objectives of access cavity - Morphology: Cars EJ, Skidmore AE. Configuration preparation and deviation of root canals of maxillary first 2. To know the proper procedure of performing access premolars. Oral Surg 1973;36:880-6, preparation 3. To know the proper outline form of access preparation for · One canal - 9% individual teeth as dictated by the internal anatomy · One root-37% · Two canals - 85% Objectives of Access Cavity Preparation: · Two roots - 57% 1. To create a smooth, straight – line path to the canal · Three canals - 6% system up to the apex · Three roots – 6% 2. To remove caries and debris from the chamber - Access: oval preparation with greater extension to 3. To allow for complete irrigation and ease of shaping buccal and lingual 4. To establish maximum visibility to gain access up to the - Beware of mesial concavity and post-treatment end of the canal (apical foramen) fractures Second Premolar - Average length Ideal Access Results in: → Maxillary: 21.5 mm → mand:22.3 mm 1. Straight entry into the canal orifices, with the line angles - Access: ovoid forming a funnel that drops smoothly into the canal or - Morphology- Vertucci FJ, Seelig A, Gillis R. Root canals canal morphology of the human maxillary second 2. Quality endodontic result premolar. Oral Surg 1974;38:456-64. DR. Sheikha Ismael ENDODONTICS Note: “Variation of root canal anatomy is more of a rule rather than an exception” Key objective: CLEANING, SHAPING, OBTURATION Ways of Gaining Access into the Canal The best area to gain access to the apical foramen is through the labial or incisal edge But why do we put our access to the lingual? → ESTHETICS Main cause of persistent infection is due to: Inadequate access Inadequate cleaning and shaping of the canal Endodontic Block If access is small: - calibrated instrument used to measure files 1. You cannot locate all of the canals - a measuring device features half millimeter depth 2. Incomplete cleaning because apical end can be guides to ensure accurate measurements inaccessible - this makes it easier to measure the length → faulty canal access = infection - used to measure the files, paper points, gutta 3. Perforations: man-made canals percha, and spreaders 4. Ledges – step being created - the vertical slot located on the side part is used if the 5. Strip side of danger zone length of the file is more than 27.5 mm 6. Zipping of the apical end - good brand = good quality = does not wart when 7. Opening up of the apical end sterilized 8. Formation of an elbow Endodontic Spoon excavator - used for removal of dental caries inside the pulp chamber - can also be used to remove pulp from pulp Steps of Access Cavity Preparation chambers, specially in the molars during access preparation 1. Study the preoperative radiograph - this is longer compared to normal spoon excavator 2. Remove all caries, weak restorations and do crown build – up after locating the canal Plastic FIlling Instrument / Woodson 3. Draw outline form on the lingual or occlusal surface of the - used for placement of temporary filling material tooth → cavit / fermin - usually used as temporary filling 4. Rubber dam isolation material 5. Use #4 round bur for initial access through the enamel → cement spatula - used to get a little amount of cavit then dentin / fermin 6. When the bur “drops in”, unroof the pulp chamber - used also during rubber dam isolation (pang ayos nung sa clamp) Others: ○ Mouth Mirror ○ Endodontic Pliers - Tweezers ○ Periodontal Probe - used to measure depth of sulcus; to assess if tooth has periodontal problem ○ Instrument Trays Instruments for Taking Radiographs FIlm Positioners - paralleling device to prevent and lessen distortion (used as a guide) - minimal distortion = normally -0.5 if there is distortion, 0 if none FIlm Holders - used for impacted 3rd molars Instruments and Materials for Rubber Dam Application Rubber Dam Sheets - medium - size is 6x6 - preferably green or blue - 5x5 for pedia px Template  DR. Sheikha Ismael ENDODONTICS Rubber Dam Puncher - used to create or hold on rubber dam sheet Electronic Devices: - can be substituted by surgical scissors ○ Electronic Apex Locator Rubber Dam Frame (plastic) - accurate way of knowing the WL - Advantage of plastic is that you don't have to remove - No xray needed it during taking of radiographs - Fake ones can deteriorate once sterilized - Used to hold rubber dam sheet Instruments for Canal Preparation Rubber Dam Clamps - parts: 1. bow - always on the distal Intracanal Instruments: files 2. holes 1. Materials 3. neck - hug the neck of the tooth; located on ○ Stainless Steel the cervical third for stability - stiff ( if u precurved the file, it remains 4. wing - placed on the contact points precurved; rigid) Rubber Dam Forceps - less carbon 2%; replaced by chromium 12- - used to place the clamp on the tooth 24 % ○ Nickel Titanium (NiTi) - flexible Instruments for Access Preparation - goes back to original form when curved ○ H - File (Hedstrom) → ENDO ACCESS BURS, LONG SHANK BURS, LN BUR - easier to break Round bur #1 is for - cross section = round Excavabur (Dentsply) / lower incisors ○ K - File (Kerr) ROund Round burs are for - more flexible, more efficient (#1,2,4) / going into the - cross section = one point is triangular , one Carbide chamber point is rectangular making it more flexible Diamonds 2. Engine Vs. Hand Driven Long tapering bur ○ Engine that creates a funnel - reduced control shape for easier access ○ Hand Driven Endo Z bur Non-cutting tip - permit proper shaping of canals; maintain (Dentsply) prevents penetration maximum control, final preparation is finished of floor and canal with filling walls - ISO standardized files ○ Parts Safe ended tip Land diamond bur Flutes - where debris settles; working area To remove pulp that is always 16mm DIamendo chamber roof ○ Comes in 4 lengths (Dentsply) without damaging floor 21 mm 25 mm 28 mm Thin, Long Used to diverge 31 mm pointed non chamber to directly ○ Numbered end cutting see orifices 06,08,10 (by 2s) fissure bur 15-60 (by 5) 60 - 140 (by 10) note: up to size 30 is available in the market Gates Glidden Drills ○ Color Coded - used to enlarge orifice but it is not recommended 6 (pink), 8 (gray), 10 (purple) ○ Exhibit 2% taper From the tip of the file, there is a 0.20mm increase in taper per mm away from Do. The tip being the narrowest portion Instruments for WL Determination Note: Standardization is for: QUALITY CONTROL, CONVENIENCE, UNIFORMITY, CORRELATION OF Endo Block - For measuring INSTRUMENTS AND MATERIALS, IMPROVED Instrument Stops COMMUNICATION - used to find the working length - reference point: - anterior = incisal edges - posterior = cusp tips and marginal ridges - rubber stopper - should be flat and at rest - directional stoppers - guide if the roots are bend or curve  DR. Sheikha Ismael ENDODONTICS Non - Standardized files ○ Barbed Broach Use to remove the pulp Can only be used in large canals If used in small er canals, it results in instrument separation (nababali) Disadvantage: extensions (tinik) ○ Canal Probes used for narrow or small canals size 10 and 12 is recommended Instruments and Materials Used in Obturation Lentulo Spiral - Used to spread the cement / sealer inside the canal - Additional arma only - Gutta percha - coat it with sealer then lagay na sa canal; no need to use lentulo spiral Spreader - pointed end - comes in sizes: 25, 30, 35 - looks like and endodontic explorer but is longer with a pointed tip not recommended ; only hand spreader is reco bc u can control it