root canal access Flashcards
variability of root canal system
1) lateral, accessory, secondary
2) bi or trifurcation
3( fusions
4) transversal anastomoses
5) apical delta
6) isthmus
7) fins
root canal classifications
1) weines or vetucci
lateral incisor
1) small pulp chamber
2) one canal almost 100%
3) 53% has a curvature
maxillary centrals
1) two pulp horns
2) lingual shoulder
3) one canal almost 100%
4) multiple canals is unusual
maxillary canine
1) in the middle third, root canal presents a buccopalatal enlargement
1) almost 100% one canal
3) foramen is near apex or laterally deported when apical curvature is present
max first premolar
1) flattened MD direction with pulp horns on B and P sides
2) one canal 26%
3) two canal 69%
4) 3 canals 5%
max second premolar
1) one canal 75%
2) two canal 24%
3) three canal 1%
4) flattened MD pulp chamber
palatal root
1) most massice and longest one
2) buccal apical curvature
3) in general, one canal
disto buccal root
1) straight, usually only one canal
mesiobuccal root
1) second canal up to 95%
2) ty
maxillary second molar
1) less wide, roots are closer
2) MB 2 prevalence 60%
3) root fusion can occur in buccal roots, with 3 and 2 canals are present
4) rare, the fusion may concern three roots
5) the fusion can be incomplete, leading to a c shaped canal
mesiobuccal root, how to locate it (2 roots)
1) modify the access cavity, a rhombiodal form
2) 1-2 mm from the palatal orifice, sometimes it is medially under the marginally ridge
3) the negotiation of MB2 is difficult
mandibular incisors
1) one flat canal in MD direction 60%
2) 45% 2 canals
3) type II most of the time
mand canine
1) one canal with ovoid shape
2) rare 2 canals 3-6%
acess cavity
1) oval for incisors to canine
mand incisors 2 canals, how to find it
1) radiograph
mandibular first premolar
1) one canal 74-76%
2) 2 canals 25%
mand second premolar
1) 98% one canal
2) two canals 2.5%
3) three canals 0.4%
mand first molar
1) 2 roots, one meisal and dstal
2) large in BL direction and thin in MD direction
mesial root
1) 2 canals 93.3%
2) canals join 40%
distal root
1) one canal 71%
2) two canals in 28%
3) canals join 85%
radix
1) extra root
2) if lingual, radix entomolaris 3-4%
3) if buccal, paramolaris 0.5%
mandibular second molar
1) single canal is 1.7%
2) most likely 2 roots, mesial and distal
3( 2 canals in mesial 92%
4) 1 canal is distal 85%
law of cenrality
1) floor of pulp chamber is always in the center of the toot hat the level of the CEJ
law of concentricity
1) walls of pulp cmaber are concentric to external surface of the toot hat the CEJ
law of CEJ
1) distance from extensal surface of the clinical crown to the wall of the pulp chamber is the same throughout
law of symmetry
1) orifices of the canal are equidistant from a line drawn in the MD direction through the pulp chamber
2) orifices line on a line perpendicular to the line drawn in MD direction t
laws of color change
1) pulp chamber is darker compared to dentin walls
lae of orifice location
1) alwaYs at the jnction between walls and floor
access cavity guide
1) remove all careis
2) unroof pulp chamber
3) remove pulp
4) preserve pulp floor
5) achieve straight or direct line access to apical 1/3 or to inital curvature
refer to bitwing
1) evaluate size of pulp chamaber
1) identify pulp stones
unroofing
1) carbide or diamond burs
2) catch the lip of the chamber roof and brush bur coronally
3) safety tip burs
