Pulp Chamber and Pulp Canals PDF

PULP CHAMBER AND PULP CANALS BALABA | BAQUIAL | ESCABARTE | MAAT | MAMALANGKAS | PILVERA | REMITARES  INTRODUCTION TO PULP CAVITY The Pulp Cavity is the central space inside a tooth that holds the soft tissue known as pulp, which contain...

PULP CHAMBER AND PULP CANALS BALABA | BAQUIAL | ESCABARTE | MAAT | MAMALANGKAS | PILVERA | REMITARES  INTRODUCTION TO PULP CAVITY The Pulp Cavity is the central space inside a tooth that holds the soft tissue known as pulp, which contains nerves, blood vessels, and connective tissue. Pulp Chamber, located in the crown of the tooth. Root Canals, which extend through each root. STRUCTURE OF THE PULP CHAMBER Pulp chamber is a hollow space within the tooth that houses the dental pulp It is centrally located in the crown of the tooth, extending down into the roots. It is composed of dental pulp and collagen fibers Functions: IT SUPPLIES NUTRIENTS TO THE TOOTH Transmit sensory information (pain, temp) Responds to injury by forming secondary dentin SIZE OF THE PULP CAVITY The size of the pulp chamber depends on the age of the tooth and its history of trauma. The Pulp cavity is much larger in a young individual than in an adult and should be considered before extensive tooth reduction, specially in a young person. The size of the pulp cavity in a given tooth should be compared with that in the other teeth. SIZE OF THE PULP CAVITY  SIZE OF THE PULP CAVITY FORAMEN The neurovascular bundle, which supplies the internal contents of the pulp cavity, enters through the apical foramen or Foramina the space that leads to the main root canal is called supplementary or lateral canal and if the root canal breaks up into multiple tiny canals, its referred to Dental system  SIZE OF THE PULP CAVITY DEMARCATION OF PULP CAVITY AND CAVITY The cementoenamel junction (CEJ) is not quite at the level at which the root canal becomes the pulp chamber. Enamel covers the external surface of the dentin, which makes up part of the pulp chamber, Cementum covers the entire external dentinal surface of the root canal space. The pulp within the chamber appears to be more cellular than pulp found within the pulp of the canal  SIZE OF THE PULP CAVITY PULP HORNS The pulpal tissues that occupy these prolongations are called pulp horns The prominence of the cusp or lobes corresponds with the development of the pulp horns Cusp or labial lobes are prominent ( as in young individuals) one should expect to find equally prominent pulp horns underlying these structures. MAXILLARY CENTRAL INCISOR Labiolingual Section: The pulp chamber is very narrow in the incisal region. If a great amount of secondary or irritation- induced dentin has been produced, this portion of the pulp chamber may be partially or completely obliterated (Figure 13-8, A, 3). In the cervical region of the tooth, the pulp chamber increases to its largest labiolingual dimension. The apical foramen is usually located near the very tip of the root but may be located slightly to the labial (Figure 13-8, A, 3, 4, and 5) or lingual aspect of the root (Figure 13-8, A, 1 and 6).  MAXILLARY CENTRAL INCISOR MESIODISTAL SECTION: THE PULP CHAMBER IS WIDER IN THE MESIODISTAL DIMENSION THAN IN THE LABIOLINGUAL DIMENSION. IF PROMINENT MAMELONS (SEE FIGURE 1-10, B) ARE OR HAVE BEEN PRESENT, IT IS NOT UNUSUAL TO FIND DEFINITE PROLONGATIONS OR PULP HORNS IN THE INCISAL REGION OF THE TOOTH (FIGURE 13-8, B, 5 AND 6). THE POSITION OF THE APICAL FORAMEN IS USUALLY SLIGHTLY OFF CENTER FROM THE TIP OF THE ROOT, BUT SOME FORAMINA DEVIATE DRASTICALLY FROM THE APEX OF THE ROOT (FIGURE 13-8, B, 6).  MAXILLARY CENTRAL CERVICAL AND MIDROOT CROSS SECTION: INCISOR THE PULP CAVITY IS WIDEST AT ABOUT THE CERVICAL LEVEL, AND THE PULP CHAMBER IS GENERALLY CENTERED WITHIN THE DENTIN OF THE ROOT (FIGURE 13-8, C, 1 THROUGH 5). IN YOUNG INDIVIDUALS THE PULP CHAMBER IS ROUGHLY TRIANGULAR IN OUTLINE, WITH THE BASE OF THE TRIANGLE AT THE LABIAL ASPECT OF THE ROOT (FIGURE 13-8, C, 5). AS THE AMOUNT OF SECONDARY OR REACTIVE DENTIN INCREASES, THE PULP CHAMBER BECOMES MORE ROUND OR CRESCENT-SHAPED (FIGURE 13-8, C, 3, 4, AND 6). THE OUTLINE FORM OF THE ROOT AT THE CERVICAL LEVEL IS TYPICALLY TRIANGULAR WITH ROUNDED CORNERS (FIGURE 13-8, C, 5 AND 6), BUT SOME ARE MORE RECTANGULAR OR ANGULAR WITH ROUNDED CORNERS (FIGURE 13-8, C, 1 THROUGH 4) THE ROOT AND PULP CANAL TEND TO BE ROUNDER AT THE MIDROOT LEVEL (FIGURE 13-8, D, 1 THROUGH 6) THAN AT THE CERVICAL LEVEL.  MAXILLARY LATERAL INCISOR LABIOLINGUAL SECTION: THE PULP CHAMBER IS NARROW IN THE INCISAL REGION AND MAY BECOME VERY WIDE AT THE CERVICAL LEVEL OF THE TOOTH (FIGURE 13-9, A, 1, 2, 3, AND 5). THOSE TEETH LACKING THIS CERVICAL ENLARGEMENT OF THE PULP CHAMBER POSSESS A ROOT CANAL THAT TAPERS SLIGHTLY TO THE APICAL CONSTRICTION (FIGURE 13-9, A, 4 AND 6). MANY OF THE APICAL FORAMINA APPEAR TO BE LOCATED AT THE TIP OF THE ROOT IN THE LABIOLINGUAL ASPECT (FIGURE 13-9, A, 1, 4, AND 6), WHEREAS SOME EXIT ON THE LABIAL (FIGURE 13-9, A, 2, AND 3) OR LINGUAL ASPECT OF THE ROOT TIP (FIGURE 13-9, A, 5).  MAXILLARY MESIODISTAL SECTION: LATERAL INCISOR THE PULPAL PROJECTIONS OR PULP HORNS APPEAR TO BE BLUNTED WHEN VIEWED FROM THE LABIAL ASPECT OF THE TOOTH. THE PULP CHAMBER AND ROOT CANAL GRADUALLY TAPER TOWARD THE APEX, WHICH OFTEN DEMONSTRATES A SIGNIFICANT CURVE TOWARD THE DISTAL IN THE APICAL REGION (FIGURE 13-9, B, 1 THROUGH 4, AND 6) CROSS AND MIDROOT CROSS SECTION: THE CERVICAL CROSS SECTION SHOWS THE PULP CHAMBER TO BE CENTERED WITHIN THE ROOT. THE OUTLINE FORM OF THIS TOOTH MAY BE TRIANGULAR, OVAL, OR ROUND (FIGURE 13-9, C, 1 THROUGH 6). THE PULP CHAMBER GENERALLY FOLLOWS THE OUTLINE FORM OF THE ROOT, BUT SECONDARY DENTIN MAY NARROW THE CANAL SIGNI- FICANTLY (FIGURE 13-9, D, 4 AND 6).  MAXILLARY CANINE LABIOLINGUAL SECTION: THE SIZE OF THE PULP CHAMBER OF THIS TOOTH MAY ALSO BE THE LARGEST IN THE MOUTH. IF A PROMINENT CUSP IS PRESENT, A LONG NARROW PROJECTION FROM THE PULP CHAMBER (THE PULP HORN) WILL BE PRESENT. THE PULP CHAMBER AND INCISAL THIRD OR HALF OF THE ROOT CANAL MAY BE VERY WIDE. (FIGURE 13-10, A, 4, 5, 6, AND 8; D, 16, 17, AND 18) IN OTHER INSTANCES, A ROOT CANAL MAY TAPER EVENLY FROM THE PULP CHAMBER TO THE APEX OF THE ROOT. (FIGURE 13-10, A, 9; D, 10, 11, 13, AND 14 ) SOME CANINES HAVE SEVERE CURVES IN THE APICAL ASPECT OF THE ROOT. (FIGURE 13-10, A, 3 AND 7 )  MAXILLARY CANINE MESIODISTAL SECTION: A MESIAL OR DISTAL CURVE OF THE APICAL ROOT MAY BE PRESENT (FIGURE 13-10, B, 1, 4, 6, AND 8; E, 14, 17, AND 18). THE APICAL FORAMEN MAY APPEAR TO EXIT AT THE TIP OF THE ROOT (FIGURE 13-10, B, 1, 3 THROUGH 5, 7, AND 9; E, 10, 11, 13, 14, 17, AND 18) OR SLIGHTLY TO THE MESIAL OR DISTAL ASPECT OF THE ROOT (FIGURE 13-10, B, 2, 6, AND 8; E, 12, 15, AND 16 ). CERVICAL CROSS SECTION: THE SHAPE OF THE ROOT AND PULP CAVITY IS OVAL (FIGURE 13-10, C, 6, 7, AND 9), TRIANGULAR (FIGURE 13- 10, C, 8), OR ELLIPTICAL (FIGURE 13-10, C, 1 THROUGH 5). THE PULP CHAMBER AND CANAL ARE OFTEN CENTERED WITHIN THE CROWN AND ROOT (FIGURE 13-10, C, 1, 3, 4, AND 9).  MAXILLARY FIRST PREMOLAR BUCCOLINGUAL SECTION: THE MAXILLARY FIRST PREMOLAR MAY HAVE TWO WELL-DEVELOPED ROOTS, TWO ROOT PROJECTIONS THAT ARE NOT FULLY SEPARATED OR ONE BROAD ROOT. THE PULP HORN USUALLY EXTENDS FURTHER INCISALLY UNDER THE BUCCAL CUSP. TEETH HAVING TWO SEPARATE CANALS USUALLY DEMONSTRATE A RATHER SMALL PULP CHAMBER IN THE INCISAL-APICAL DIRECTION (FIGURE 13-11, A, 1, 2, AND 9; D, 11 AND 14). THE SHAPE OF THE PULP CHAMBERS TENDS TO BE SQUARE. OR RECTANGULAR. THE ROOT CANAL OFTEN APPEARS TO EXIT AT THE TIP OF THE ROOT SLIGHTLY TO THE LABIAL OR LINGUAL (FIGURE 13-11, A, 2), OR A COMBINATION OF THE TWO LOCATIONS.  MAXILLARY FIRST PREMOLAR MESIODISTAL SECTION: THE PULP HORNS APPEAR BLUNTED FROM THE MESIAL OR DISTAL ASPECT. THE PULP CAVITY TAPERS SLIGHTLY FROM THE OCCLUSAL ASPECT TO THE APICAL FORAMEN. THE APICAL FORAMEN APPEARS TO EXIT AT THE TIP OF THE ROOT MOST OF THE TIME (FIGURE 13-11, B, 1, 2, 3, AND 6 THROUGH 9; E, 10 AND 12 THROUGH 18), BUT SOME APPEAR TO EXIT ON THE MESIAL OR DISTAL ASPECTS OF THE ROOT (FIGURE 13-11, B, 4 AND 5; E, 11). CERVICAL CROSS SECTION: THE CROSS SECTION AT THE CERVICAL LEVEL SHOWS THE KIDNEY SHAPED OUTLINE. THE PULP CAVITY MAY DEMONSTRATE A CONSTRICTION ADJACENT TO THE DEVELOPMENTAL GROOVE OR IT MAY FOLLOW THE GENERAL OUTLINE OF THE ROOT SURFACE.  MAXILLARY FIRST PREMOLAR.CERVICAL CROSS SECTION: SOME ROOTS DEMONSTRATE TWO SEPARATE ROOT CANALS WHEREAS A CROSS SECTION OF A THREE- ROOTED MAXILLARY FIRST PREMOLAR WILL SHOW THREE SEPARATE CANALS.  MAXILLARY SECOND PREMOLAR Buccolingual section Most maxillary second premolars have only one root and canal. two roots are possible, although two canals within a single root may also be found. PULP HORNS: ( A,1 2, 6, 7, & D, 10, 11, 12, 14, 16, and 17) NONEXISTENT PULP HORNS: ( A, 3, 4, 5, and 9 ; D,13 , 15 and 18) PULP CAVITY: (A, 1 , 2, 4, 6, and 8, D, 11, 12, 13, and 18) TWO CANALS: ( A, 5; D, 15 and 17) APICAL THIRD ( D, 10 ,15 , and 16) BUCCAL AND LINGUAL; ( A, 2; D, 12 and 18) CONSTRICTIONS ( D, 10) TIP OF THE ROOT ( A , 1 , 2, 5, 6, and 8; D, 11 , 12 , and 14 through 18)  MAXILLARY SECOND PREMOLAR ROOT ASPECT:( A, 4; D, 13) on the lingual aspect of the root (A, 7 and 9) or on the both sides of the root tip ( A, 3; D, 10 and 15) MAXILLARY SECOND PREMOLAR MESIODISTAL SECTION The view of the pulp cavity in the mesiodistal section of the second maxillary premolar does not vary from that found in the maxillary first first premolar. APICAL FORAMEN: ( A , 2 , 6, and D, 10 and 13) or appear to exit at the root tip ( B , 1 , 3 , 4, 5, 7 and 8 ; E , 11, 12, and 14 through 18) MAXILLARY SECOND PREMOLAR CERVICAL CROSS SECTION. The Cervical cross section of the maxillary second premolar is usually oval ( C , 2 and 4 through 9) Some teeth having a kidney shaped cross section ( C 1 and 3) Middle of the canal space ( C , 1, 4 , 6 and 9) an entire separation ( C, 2) Elliptical pulp cavity ( C , 3 , 5 , 7, and 8)  MAXILLARY FIRST MOLAR BUCCOLINGUAL SECTION The pulp horns are usually prominent in this tooth. ( A , 1, and 4 through 8 D , 10 through 13 and 15 through 18) Palatal root usually has the largest canal ( A, 1 , 2 , 3, 5 and 6 ; D , 10 , 15 , 17 , 18) Mesiobuccal canal is often very small ( A, 2 , and , 6 d 10, 14, and 17) Some Mesiobuccal canals may be very wide within a very wide root ( A, 9 ; D 12 and 13)  MAXILLARY FIRST MOLAR MESIODISTAL SECTION The mesiodistal section of the maxillary first molar includes the distobuccal root, which is not visible on the previously mentioned buccolingual section. The mesiobuccal; ( B , 1, through 8 ; E , 12 , 14 and 15) some buccal canals are relatively straight ( E, 10 ,11 and 13) Mesiobuccal and Distobuccal pulp horn ; ( B , 1 and 3 through 9; E , 10 through 13 and 15 through 18) in some teeth the pulp horns are equal size ( B, 2, E, 14)  MAXILLARY FIRST MOLAR CERVICAL CROOS SECTION The cervical outline form of the maxillary first molar rhomboid with rounded corners ( C, 1 through 5) Mesiobuccal and palatal canal: ( C , 7 , 8 and 9 ) Connecting the mesiobuccal and the palatal canal ( C, 8)  MAXILLARY FIRST MOLAR MIDROOT CROSS SECTION The midroot sections were added to the mola descriptions because some molar posses more than one canal within the root. The palatal root is usually the largest root having round outline form. Mesiobuccal canal elongated ; (C, 6 and 9) Eliptical C, 7) or round ( C , 8 and 9) Dentin Abundant: ( C, 9 ) MAXILLARY 2ND & 3RD MOLAR MAXILLARY 2ND MOLAR INTRACORONAL ANATOMY identical to the maxillary first molar 3-4 cusps present The crown form, which dictates the pulp space anatomy, may be rhomboidal or a triangle with rounded edges. INTRARADICULAR ANATOMY has 3 roots but they converge more towards each other number of canals varies from 2-4, with 3 canals occurring more commonly. The shape of root canal at various levels ARE: Cervical: Triangular Apical third: Round  MAXILLARY 3RD MOLAR 1. Large variation is seen both in the intracoronal and intraradicular anatomy because of the shape, size, number of cusps and roots, and the spatial orientation of roots. 2. The tooth has 2-4 cusps; the intracoronal anatomy depends on the number of cusps. 3. 3 roots and 3 canals is a common occurrence 4. The root can exhibit curvature of different nature. 5. The intracoronal and intraradicular anatomy of maxillary third molar cannot be generalized.  MANDIBULAR CENTRAL INCISOR LABIOLINGUAL SECTION (FIGURE 13-16, A AND D) PULP CHAMBER SIZE: VERY LARGE. - (A, 1, 2, 4, 6, 8; D, 10, 11, 13, 17) INTERMEDIATE IN SIZE. - (A, 3, 5, 7, 9; D, 12, 14, 15) VERY SMALL. - (D, 16, 18) ROOT CANAL SHAPE: CANAL MAY GENTLY TAPER TOWARD THE APEX. - (A, 2, 3, 7; D, 10, 11, 14, 16, 18) CANAL MAY NARROW ABRUPTLY IN THE LAST 3–4 MM OF THE ROOT. (A, 1, 4, 5, 6, 8; D, 12, 13, 15, 17). APICAL FORAMEN: MAY EXIT AT THE TRUE APEX OF THE ROOT. - (A, 1, 4, 6, 7, 9; D, 11, 12, 15, 16, 18). MAY EXIT ON THE BUCCAL ASPECT (CLOSER TO THE OUTER SURFACE).- (A, 2, 3, 5, 8; D, 10, 13, 14, 17) MESIODISTAL SECTION (FIGURE 13-16, B AND E) MANDIBULAR CENTRAL INCISOR IRRITATION DENTIN: SOMETIMES SECONDARY OR TERTIARY DENTIN MAY FORM DUE TO IRRITATION, WHICH CAN COMPLICATE ROOT CANAL TREATMENTS (D, 16, 18; E, 13, 18). CANAL EXIT: THE CANAL MAY EXIT AT THE TRUE APEX (B, 2, 5, 8; E, 12, 14, 16, 17) OR SLIGHTLY OFF-CENTER (B, 1, 3, 4, 6, 7, 9; E, 10, 11, 13, 15, 18). CERVICAL CROSS SECTION (FIGURE 13-16, C) SHAPE OF THE ROOT: THE ROOT’S MESIODISTAL DIMENSION IS SMALL, BUT THE LABIOLINGUAL DIMENSION IS LARGE. VARIABILITY: THE SHAPE OF THE ROOT CAN VARY, BEING ROUND, OVAL, OR ELLIPTICAL.  MANDIBULAR LABIOLINGUAL SECTION (FIGURE 13-18, A LATERAL INCISOR AND D) PULP CHAMBER SIZE: VERY LARGE (A, 2, 4, 5, 8, 9; D, 10, 11, 16, 17, 18). INTERMEDIATE (A, 1, 3, 6, 7; D, 12). SMALL (D, 14, 15). CANAL TAPER: THE CANAL MAY TAPER GENTLY TO THE APEX (A, 1, 2, 4, 6, 7, 9; D, 12, 14–17) OR IT MAY NARROW ABRUPTLYIN THE LAST 3-4 MM OF THE CANAL (A, 3, 5, 8; D, 10–13). APICAL FORAMEN: THE EXIT CAN BE AT THE APEX OF THE ROOT (A, 1–6, 8, 9; D, 12–15, 17, 18) OR IT MAY EXIT ON THE BUCCAL OR LINGUAL SIDE OF THE ROOT (A, 7; D, 10, 11, 16).  MANDIBULAR MESIODISTAL SECTION (FIGURE 13-18, B AND E) LATERAL INCISOR CANAL TAPER: THE CANAL TAPERS GENTLY TOWARD THE APEX. CANAL EXIT: THE APICAL FORAMEN MAY EXIT AT THE APEX (A, 1, 2, 3, 6, 9; D, 12–15, 17, 18) OR MESIAL OR DISTAL TO IT (A, 5, 7, 8; D, 10, 11, 16). CERVICAL CROSS SECTION (FIGURE 13-18, C) ROOT SHAPE: THE SHAPE CAN VARY, BUT IS GENERALLY OVAL OR ELLIPTICAL. SOME SECTIONS MAY EVEN RESEMBLE MANDIBULAR CANINES. CANAL SHAPE: THE ROOT CANAL MIRRORS THE SHAPE OF THE ROOT, AND SOME ROOTS SHOW GROOVES ALONG THE SURFACE (C, 6).  MANDIBULAR CANINE Labiolingual Section The pulp chamber usually is very wide (Figure 13-19, A, 1, 3, 4, 5, and 7; D, 10, 12, 14, 15, 17, and 18) but may be average to small (Figure 13-19, A, 2, 6, and 9; D, 11, 13, and 16). The apical foramen often appears to exit at the tip of the apex (Figure 13-19, A, 3, 5, 7, and 9; D, 10, 12, 14 through 16), slightly buccally (Figure 13-19, A, 1, 2, 6, and 8; D, 11, 13, and 17), or lingually to the root tip (Figure 13-19, D, 18). MANDIBULAR CANINE Mesiodistal Section THE PULP CHAMBER AND CANAL SHOW A CONTINUOUS GENTLE TAPER TO THE APEX, WHERE THE APICAL FORAMEN APPEARS TO EXIT AT THE TIP OF THE ROOT (FIGURE 13-19, B, 1 THROUGH 4; E, 10, 11, 13, 15, AND 17) OR SLIGHTLY MESIALLY OR DISTALLY TO THE ROOT TIP (FIGURE 13-19, B, 5 THROUGH 7; E, 12, 14, AND 18). Cervical Cross Section THE OUTLINE FORM OF THE ROOT MAY BE OVAL (FIGURE 13-19, C, 1, 4, 7, AND 8), RECTANGULAR (FIGURE 13-19, C, 2, 5, 6, AND 9), OR TRIANGULAR (FIGURE 13-19, C, 3). THE SIZE AND SHAPE OF THE CANAL ARE ALSO VARIABLE. THE PULP CAVITY OUTLINE FORM CLOSELY RESEMBLES THE ROOT FORM. MANDIBULAR FIRST PREMOLAR Buccolingual Section The pulp chamber is usually very large. The pulp cavity may taper gently toward the apex (Figure 13-20, A, 2, 3, 5, and 6; D, 12 and 13) or abruptly as the root canal starts (Figure 13-20, A, 1, 4, and 7; D, 11, 17, and 18), or it may gently and abruptly constrict in the apical region (Figure 13-20, A, 2 and 8; D, 10, 14, 15, and 16). The apical foramen usually appears to exit at the apex (Figure 13-20, A, 2, 3, 5, 6, 7, and 9; D, 10 through 13, and 18) or slightly to the buccal (Figure 13-20, A, 8; D, 14, 15, and 16) or lingual aspect of the root tip (Figure 13- 20, A, 1 and 4; D, 17). MANDIBULAR FIRST PREMOLAR Mesiodistal Section The pulp chamber and root canal taper gently to the apex. The apical foramen may appear to exit at the tip of the root (Figure 13-20, B, 3, 5, 8, and 9; E, 11, 14, 17, and 18) or on the buccal or lingual aspect of the root (Figure 13-20, B, 1, 2, 4, 6, and 7; E, 10, 12, 13, 15, and 16). Cervical Cross Section The pulp cavity may be rounded (Figure 13-20, C, 5), elliptical (Figure 13-20, C, 1, 3, 4, 6, 8, and 9), or triangular (Figure 13-20, C, 7), depending on the external shape of the root. If two separate canals are present and the cross section is below the bifurcation level, two or three round canals would be seen rather than elliptical or ribbon-shaped canals.  MANDIBULAR ANATOMY: SECOND MOLAR - SIMILAR TO MANDIBULAR 1ST MOLAR. - STRAIGHTER ROOTS WITH LESS FURCATION BUCCOLINGUAL SECTION DEVIATION. PULP CHAMBER: - PROMINENT PULP HORNS - (A, 1, 3, 5, 6, 8, AND 9; D, 10, 13, 14, 15, 17, AND 18), - SMALL TO NONEXISTENT (A, 2, 4, AND 7; D, 11, 12, AND 16). - PULP CHAMBER OF THE MESIAL ROOT IS WELL- DEFINED - ( A: 1, 3, 5, 6, AND 8 D: 12, 13, 14, 16, 17, AND 18) PULP CHAMBER SHAPE (EXCLUDING PULP HORNS): SQUARE SHAPE: A (1, 3, AND 8), D (10, 12, 14, 16, 17, AND 18) RECTANGULAR SHAPE: A (5 AND 6), D (13)  MANDIBULAR APICAL FORAMEN: SECOND MOLAR USUALLY LOCATED AT ROOT TIP (A, 1, 3, AND 6; D, 12, 17, AND 18) OCCASIONALLY EXITS TO BUCCAL OR BUCCOLINGUAL SECTION LINGUAL SIDE OF APEX (A, 5 AND 8; D, 14 AND 16) DISTAL ROOT PULP CHAMBER NOT EASILY IDENTIFIABLE DUE TO LARGE PULP CANAL. TYPICALLY ONE CANAL; TWO SEPARATE OR PARTIALLY SEPARATE CANALS POSSIBLE ( D, 10) PULP HORNS: PRESENT BUT LESS PROMINENT THAN IN MESIAL ROOT (A, 2, 4, 7, AND 9; D, 11 AND 15) MORE PROMINENT IF TWO CANALS ARE PRESENT (D, 10)  MANDIBULAR BUCCOLINGUAL SECTION SECOND MOLAR CANAL TAPERING: TAPERS GENTLY TO APICAL CONSTRICTION (A, 2 AND 7; D, 10 AND 15) ABRUPT CONSTRICTION IN LAST 2-3 MM OF CANAL (A, 4 AND 9; D, 11) APICAL FORAMEN: TYPICALLY LOCATED AT ROOT TIP (A, 1, 4, 7, AND 9; D, 10, 11, AND 15) MESIODISTAL SECTION COMPARISON WITH MANDIBULAR FIRST MOLAR: SIMILAR MESIODISTAL SECTIONS. ROOTS IN THE MANDIBULAR FIRST MOLAR TEND TO BE STRAIGHTER AND CLOSER TOGETHER (LESS FURCATION DEVIATION).  MANDIBULAR MESIODISTAL SECTION SECOND MOLAR PULP HORNS: USUALLY PROMINENT (B: 1, 2, 3, 5, 7, 8, 9; E: 10, 11, 13, 15, 18). SOME ARE SMALL OR ABSENT (B: 4, 6; E: 12, 14, 16, 17). PULP CHAMBER: RECTANGULAR SHAPE (EXCLUDING PULP HORNS). SIZE VARIES: VERY LARGE IN SOME CASES (B: 1, 3, 4, 5, 7, 9; E: 13, 16). VERY SMALL IN OTHERS (B: 2, 8; E: 11, 14, 17, 18). MESIAL CANAL CURVATURE: CAN BE SEVERE (B: 3, 6, 8, 9; E: 11, 14, 16, 17) MODERATE (B: 2, 4, 7; E: 10, 13, 15, 18) STRAIGHT (B: 1, 5; E: 12)  MANDIBULAR MESIODISTAL SECTION SECOND MOLAR APICAL FORAMEN LOCATION ON MESIAL CANAL: TYPICALLY LOCATED AT THE TIP OF THE ROOT (B: 2, 4–7, 8; E: 11, 12, 13, 15, 17, 18). SLIGHTLY MESIAL (B: 3; E: 10, 13, 16) OR DISTAL (B: 9; E: 14) ON THE ROOT TIP. DISTAL CANAL: SLIGHTLY CURVED (B: 1–5, 7; E: 11, 14, 16) OR STRAIGHT (B: 4, 6, 8, 9; E: 10, 12, 13, 17, 18). DISTAL ROOT LENGTH: SHORTER THAN THE MESIAL ROOT (B: 1, 2, 4, 7). EQUAL TO THE MESIAL ROOT (B: 3, 5, 6; E: 10, 13, 14, 16, 17). LONGER THAN THE MESIAL ROOT (B: 8, 9; E: 11, 12, 15, 18). LARGER THAN THE MESIAL CANALS (B: 3, 4, 6– 9; E: 11, 13, 15, 16), BUT CAN BE EQUAL (B: 1, 2, 5; E: 12, 14, 18).  MANDIBULAR SECOND MOLAR MESIODISTAL SECTION APICAL FORAMEN LOCATION ON DISTAL CANAL: USUALLY LOCATED AT THE TIP OF THE ROOT (B: 1–7; E: 10–13, 16, 18). CAN EXIT MESIALLY (B: 9) OR DISTALLY (B: 8; E: 14, 15, 17) TO THE ROOT APEX. CROSS SECTIONS CERVICAL CROSS-SECTION IS TRIANGULAR OR NEARLY OVAL. MIDROOT CROSS-SECTION SHOWS A FIGURE-EIGHT OR KIDNEY SHAPE, MAKING IT HARDER TO DIFFERENTIATE THE TWO CANALS. MANDIBULAR THIRD MOLAR ANATOMY: - TWO ROOTS AND THREE CANALS ARE BUCCOLINGUAL SECTION COMMONLY PRESENT (B, 6 AND 7) - TWO CANALS OR TWO ROOTS ARE ALSO POSSIBLE (C, 8 AND 9). PULP CHAMBER: - PROMINENT PULP HORNS - (A, 1, 2, 4 THROUGH 9; D, 10, 11, 12, 14, 15, 17, AND 18) - SMALL TO NONEXISTENT (A, 3; D, 13 AND 16) MESIAL ROOTS - SQUARE PULP CHAMBER (EXCLUDING PULP HORNS) (A, 2 AND 9; D, 10, 11, 13, AND 14). - CONTAIN TWO CANALS (A, 2, 5, AND 9; D, 10, 11, AND 14), BUT A SINGLE MESIAL ROOT CAN BE PRESENT (D, 14) MANDIBULAR THIRD MOLAR MESIAL ROOT CANAL MAY BE: VERY CURVED (A, 5 AND 9; D, 10) BUCCOLINGUAL SECTION RELATIVELY STRAIGHT (A, 2; D, 11 AND 13) APICAL FORMEN LOCATED AT THE TIP OF THE ROOT (A, 1 AND 5; D, 10, 11, AND 13) BUT CAN ALSO BE BUCCALLY LOCATED (FIGURE 13-24, A, 9; D, 14). SEPARATE APICAL FORAMINA (FIGURE 13-24, A, 2 AND 5; D, 10, 11, AND 13); : EXITING THROUGH A COMMON FORAMEN (FIGURE 13-24, A, 9) DISTAL ROOT FEATURES A VERY LARGE PULP CHAMBER AND CANAL, DIFFICULT TO DELINEATE (A, 1, 3, 4, 6, 7, AND 8; D, 12, AND 15 THROUGH 18). MANDIBULAR THIRD MOLAR DISTAL ROOT PULP CANALS MAY TAPER GENTLY TO THE ROOT TIP (A, 4, 6, BUCCOLINGUAL SECTION AND 7; D, 16 AND 18). DEMONSTRATE AN ABRUPT CONSTRICTION IN THE LAST FEW MILLIMETERS (A, 1; D, 12, 15, AND 17). PULP CHAMBER GENERALLY SQUARE OR RECTANGULAR (EXCLUDING PULP HORNS). SMALL PULP CHAMBERS TEND TO SHOW A CONSTRICTION AT THE JUNCTION OF THE PULP CHAMBER AND CANAL (A, 3 AND 8). APICAL FORAMEN IN DISTAL ROOT TIP OF THE ROOT (A, 3, 6, 7, AND 8; D, 16 AND 17) BUCCALLY OR LINGUALLY LOCATED (A, 1 AND 4; D, 15 AND 18). MANDIBULAR MESIODISTAL SECTION THIRD MOLAR PULP HORNS: MAY BE PROMINENT (B, 1 AND 5; E, 10, 11, 12, 14, AND 15). SMALL (A, 4, 6, AND 7; D, 17) NEARLY ABSENT (B, 2, 3, 8, AND 9; E, 13, 16, AND 18) PULP CHAMBER: SQUARE OR RECTANGULAR WHEN VIEWED FROM THE BUCCAL ASPECT (B, 1–4, 7, AND 9; E, 10, 12, 13, 15, 17, AND 18). MAY BE SOMEWHAT SQUARE (B, 5; E, 14) MESIAL ROOT CURVATURE: SLIGHT CURVATURE (E,13, SINGLE-ROOTED) MODERATE CURVATURE (B, 1, 2, 5, 8, AND 9; E, 11, 15, AND 17) SEVERE CURVATURE (B, 3, 4, 6, AND 7; E, 10, 12, 14, 16, AND 18). MANDIBULAR CANAL WITHIN THE MESIAL ROOT: THIRD MOLAR LARGE (B, 2 AND 4; E, 10). VERY SMALL (B, 1, 3, 5, 8, AND 9; E, 11, 12, AND 14 THROUGH 18). APICAL FORAMEN: APPEAR AT THE APEX OF THE ROOT (B, 1, 2, 3, 5, 6, 8, AND 9; E, 11, 12, 14, 17, 18). MESIALLY LOCATED (B, 7). DISTALLY LOCATED (B, 4; E, 10 AND 15). LENGTH OF THE MESIAL ROOTS: EQUAL TO THE LENGTH OF THE DISTAL ROOT (B, 2, 3, AND 8; E, 10 AND 11). SHORTER THAN THE DISTAL ROOT (FIGURE 13- 24, B, 5 AND 9; E, 18). LONGER THAN THE DISTAL ROOT (FIGURE 13- 24, B, 1, 4, 6, AND 7; E, 12, 14, 15, AND 17). MANDIBULAR DISTAL CANAL: LARGER THAN THE MESIAL CANAL (B, 2–5, AND 9; E, 14 THIRD MOLAR AND 18). EQUAL IN SIZE (B, 1, 6, 7, AND 8; E, 10, 11, 12, 15, AND 17). GENTLY TAPERS TO THE APICAL CONSTRICTION (B, 1–8; E, 10–18). LOCATION OF THE APICAL FORAMEN: APPEAR AT THE APEX OF THE ROOT (B, 1–5, 7, AND 9; E, 10, 11, 12, 15, 17, AND 18). MESIAL (B, 8). DISTAL (B, 6; E, 14). ROOT AND CANAL CONFIGURATION: SOME TEETH SHOW ONLY ONE ROOT WITH ONE OR TWO CANALS. IF ONE CANAL IS PRESENT (E, 13), THE CANAL WILL BE VERY LARGE. IF THE THIRD MOLAR IS MULTIROOTED, THE CANALS WILL BE MUCH SMALLER (E, 16). MANDIBULAR CERVICAL CROSS SECTION THIRD MOLAR RECTANGULAR SHAPE (C, 1–4) TRIANGULAR SHAPE (C, 5) MIDROOT CROSS SECTION MESIAL ROOT (WHEN PRESENT): SHAPE: OVAL TO FIGURE EIGHT (C, 6 AND 7) DISTAL ROOT SHAPE: OVAL (C, 6) KIDNEY-SHAPED (C, 7) IF ROOTS ARE: FUSED (C, 8) ONLY ONE ROOT IS PRESENT (C, 9): CANALS ARE USUALLY LARGER. CANALS IN ROOTS THAT ARE: KIDNEY-SHAPED OR IN THE FORM OF A FIGURE EIGHT ARE MORE ELLIPSOIDAL. RADIOGRAPHIC : PULP CHAMBER AND CANALS - RADIOGRAPHS (X-RAYS) OR DIGITAL RADIOGRAPHY ARE USED TO DIAGNOSE AND TREAT PULPAL DISEASE. - RADIOGRAPHS CREATE A TWO- DIMENSIONAL (2D) IMAGE, COMPRESSING THESE 3D STRUCTURES INTO A FLAT VIEW. - THE HARD PARTS OF THE TOOTH APPEAR SOLID, WHILE THE PULP AND CANALS SHOW UP AS DARK, EMPTY SPACES. RADIOGRAPHIC : PULP CHAMBER AND CANALS RADIOGRAPHIC : PULP CHAMBER AND CANALS VISUALIZATION: - BUCCOLINGUAL VIEW: CAPTURING THE PULP CHAMBER AS A RADIOLUCENT SPACE WITHIN THE HARD RADIOPAQUE STRUCTURES OF ENAMEL AND DENTIN. - MESIODISTAL VIEW: FOCUSING MORE ON THE ROOT AND ITS CANAL SYSTEM  CLICNICAL APPLICATIONS ONE OF THE PRIMARY FUNCTIONS OF THE DENTIST IS TO PREVENT, INTERCEPT, AND TREAT DISEASES OR DISORDERS AFFECTING THE DENTITION. IT IS ALSO ESSENTIAL THAT THE CLINICIAN BE AWARE OF THE LOCATION AND SIZE OF THE PULP CAVITIES DURING OPERATIVE PROCEDURES TO PREVENT UNNECESSARY INFILTRATION ON THE PULP. ENDODONTIC PROCEDURES ALSO REQUIRE A THOROUGH KNOWEDGE OF THE PULP CAVITY. PERFORATION DURING ACCESS PREPARATION, FAILURE TO LOCATE ALL THE CANALS, OR PERFORATION OF THE ROOT SURFACE MAY RESULT IN THE ULTIMATE LOSS OF THE TOOTH. THEREFORE THE CLINICIAN PERFORMING ENDODONTICS MUST KNOW THE SIZE AND LOCATION OF THE PULP CHAMBER AND THE EXPECTED NUMBER OF ROOTS AND CANALS.  THANKS EVERYONE FOR LISTENING! INSIGHTS : WHEELER’S BOOK