MORPHOLOGY OF PULP IN PRIMARY & PERMANENT TEETH

DEFINITIONS

• PULP :- Defined as a special organ with a unique environment of the unyielding dentin surrounding a resistant, resilient soft tissue of mesenchymal origin reinforced with a ground substance.

• MOROHOLOGY OF PULP basically deals with configuration or structure of dental pulp.

MORPHOLOGY OF PULP IN PRIMARY TEETH

• MAXILLARY FIRST PRIMARY MOLAR:-

• Pulp cavity consist of a chamber & three pulpal canals corrosponding to 3 roots.

• Variations from this basic design may be present as anastomoses & branchings.

• The pulp chamber consists of three or four pulpal horns following the surface contour of the tooth.

• Mesio-buccal horn is the largest of pulpal horns occupying a prominent portion of pulp chamber.Apex of this horn lies slightly mesial to body of pulp chamber.

• Mesiolingual pulpal horn is second in size,quite angular & sharp.

• Distobuccal horn is smallest , sharp & occupies distobuccal angle.

• Occlusal view of the pulp chamber resembles somewhat a triangle with rounded corners.

• MANDIBULAR FIRST PRIMARY MOLAR:-

• The pulp cavity contains a chamber & 3 canals.

• Mesiobuccal & mesiolingual canals are confluent & leave the chamber in the form of a ribbon.The two canals soon separate to form a buccal & lingual canal which gradually taper to apical foramen.

• The distal pulp canal projects in ribbon fashion from floor of chamber in distal aspect.

• The pulp chamber has 4 pulpal horns.• Mesiobuccal horn,the largest of pulpal horns is

rounded & connects with mesiolingual pulp horn in a high ridge, making mesial area vulnerable to mechanical exposure.

• Distobuccal pulp horn is second in area but lacks the height of mesial horns.

• Mesiolingual horn is third in size & second in height, while distolingual pulpal horn is smallest.

• Occlusal view of pulp chamber is rhomboidal.

MAXILLARY SECOND PRIMARY MOLAR

• The pulp cavity consist of a pulp chamber & 3 pulp canals corresponding to three roots.

• These canals leave floor of chamber at the mesiobuccal & distobuccal corners & from lingual area.

• Pulp chamber has 4 pulpal horns, a fifth hor projecting from linguaal aspect of mesiolingual horn may be present.

• The mesiobuccal pulp horn is largest, pointed & extends occlusally above other cusps.

• Mesiolingual pulp horn is second in size, when combined with fifth horn it presents a bulky appearance.

• Distobuccal pulp horn is third in size,joining mesiolingual pulp horn as slight elevation.

• Distolingual pulp horn is shortest & extends only slightly above occlusal level.

MANDIBULAR SECOND PRIMARY MOLAR

• Pulp cavity is made up of a chamber & usually 3 pulp canals.

• The two mesial pulp canals are confluent as they leave floor of pulp chamber through a common orifice.

• This common canal soon divides into a larger mesiobuccal and smaller mesiolingual canal.

• Distal canal is constricted in the centre.

• All the three canals taper as they approach apical foramen conforming to shape of roots.

• Pulp chamber has 5 pulpal horns corresponding to 5 cusps.

• Mesiobuccal & mesiolingual pulp horns are largest, connected by a higher ridge of pulpal tissue.

• Distobuccal horn is smaller than mesial horns but somewhat larger than distolingual & distal horn.

• The distal horn is shortest & smallest occupying a position distal to distobuccal horn.

MAXILLARY PRIMARY CANINE

• There is a little demarcation between pulp chamber and the canal.

• The canal tapers as it approaches the apex.

• Pulp chamber follows the external contour of teeth.

• Central pulpal horn is projecting incisally farther than the reminder of pulp chamber.

MANDIBULAR PRIMARY CANINE

• Thers is no differentiation between chamber & canal.

• The canal follows the surface form of root in general & ends in a marked constriction at apical end.

• The pulp chamber follows external contour of the tooth being as wide mesiodistally as labiolingually.

MAXILLARY PRIMRY INCISORS

• Pulp cavity conforms to general outside surface of tooth.

• Pulp chamber has 3 slight projections on is incisal border.

• Single pulp canal continues from chamber with no distinct demarcation between them.

• Pulp canal tapers evenly untill it ends at apical foramen.

• In lateral incisor, there is slight demarcation between pulp chamber & canal , especially on labial & lingual aspect.

MANDIBULAR PRIMARY INCISORS

• Pulp chamber is widest mesiodistally at roof of chamber.

• Labiolingually, chamber is widest at cingulum or cervical line.

• The pulp canal is oval & tapers as it approaches the apex.

• There is definite demarcation between pulp chamber & canal in central incisor, which is not present in latral incisor.

MORPHOLOGY OF PULP IN PERMANENT TEETH

• MAXILLARY FIRST MOLAR• The pulp chamber of maxillary 1st molar is

largest in dental arch.• It consists of 4 pulp horns –

mesiobuccal,distobuccal,mesiopalatal & distopalatal.

• The arrangement of 4 pulp horns give the pulpal roof a rhomboidal shape in cross section.

• The orifice of root canals are located in three angles of floor.

• Palatal orifice is largest, round or oval in shape.

• Mesiobuccal orifice is under mesiobuccal cusp

• Distobuccal orifice is located slightly distal & palatal to mesiobuccal orifice.

• It has 3 root canals situated mesiobuccally,distobuccally & paltaly.

• Mesiobuccal canal is divided to form a second canal in 22%of cases.

• Distobuccal canal is narrow,tapering & cone shaped.

• The palatal canal is ovoid & tapers towards apex.

MANDIBULAR FIRST MOLAR• Roof of pulp chamber has 4 pulp horns.• 3 distinct orifice are present in pulpal floor

namely mesiobuccal,mesiolingual, & distal.

• Mesiobuccal orifice is under mesiobuccal cusp.

• Mesiolingual orifice is located in depression forme by mesial & lingual walls.

• Distal orifice is oval in shape.• Mesial root has 2 canals while distal root

has 1 canal.• In cross section,all three canals are ovoid

in cervical & middle third and round in apical third.

MAXILLARY SECOND MOLAR

• Pulp chamber has 4 pulp horns.• Chamber is narrower mesiodistally

than of maxillary 1st molar• Roof of pulp chamber is more

rhomboidal than maxillary 1st molar.• Orifices of 3 root canals are located

in 3 angles of floor.• If buccal root fuse to form 1 buccal

root ,tooth may have only 2 canals,1 buccal & 1 palatal.

MANDIBULAR SECOND MOLAR

• Pulp chamber is smaller than that ofmandibular 1st molar & root canal orifices are smaller & close together.

• 3 root canals are usually present , there may be only 2 canals present in some cases.

• In cross section, all the 3 canals are small and ovoid in cervical & middle third & rounded in apical third.

MAXILLARY THIRD MOLAR

• Pulp chamber is usually similar to that of maxillary 2nd mloarwith 3 canal orifices.

• Sometimes, it may also have an odd shaped chamber with 4 or 5 root canal orifices or a conical chamber with only 1 root canal.

• Anomalous configurations such as “c-shaped” pulp chamber with a “c-shaped” root canal may be found.

MANDIBULAR THIRD MOLAR

• Pulp chamber anatomically resembles the pulp chamber of mandibular 1st & 2nd molars.

• Sometimes, a “c-shaped ” root canal may also be found.

MAXILLARY FIRST PREMOLAR

• Pulp chamber is narrower mesiodistally.• 2 pulp horns are present under each cusp.• Buccal pulp horn is more prominent in young

teeth.• Floor of chamber is convex with 2 canal

orifices.• In cross section view pulp chamber is wide &

ovoid.• 2 root canals are present , whether there are

1 or 2 roots.• Palatal canal is generally larger than buccal

canal.

MANDIBULAR FIRST PREMOLAR • Pup chamber is narrower

mesiodistally while wider buccolingually.

• Buccal pulp horn is prominent.• Chamber is ovoid when seen in

cross-section.• Usually 1 canal is present which is

cone shaped & simple in outline.

MAXILLARY SECOND PREMOLAR

• Pulp chamber is wider in comparison to maxillary 1st premolar.

• 2 pulp horns are present – one buccal & one palatal.

• Floor of pulp is deeper when compared to maxillary 1st premolar.

• Usually one canal is present , when 2 canals occur they are distinct & separated along entire outline of root.

MANDIBULAR SECOND PREMLAR

• Here , lingual horn is more prominent when compared to mandibular first premolar.

• Usually one canal exit in apical foramen but in some roots , a single canal may bifurcate exiting in 2 foramina.

MAXILLARY CENTRAL INCISOR

• Pulp chamber is located in the centre of crown.

• It usually follows contours of crown & has 3 pulp horns corresponding to mamelons in a young teeth.

• Division between root canal & pulp chamber is indistinct.

• Maxillary central incisor has 1 root with 1 root canal.

• Root canal is large, conical & simple in outline & centrally rotated.

• Root canal follows direction of curved roots.

MANDIBULAR CENTRAL INCISORS

• Pulp chamber is small & flat mesiodistally.

• 3 distinct pulp horns are present in recently erupted tooth which calcify & disappear because of constant masticatory stimulus.

• Usually 1 root with 1 canal is present.• Canal is broad in cervical & middle third

of root & tapers gradually towards the apex.

• Canal appears ribbon shaped in middle third when visualize in cross –section.

MAXILARY LATERAL INCISOR• Pulp chamber is similar but

smaller than that of maxillary central incisor.

• It has 2 pulphorns corresponding to mamelons.

• Broadest part is situated incisally.

• Root canal is conical , finer than central incisor.

• In cross section canal is ovoid labiopalatally.

MANDIBULAR LATERAL INCISOR

• Pulp chamber is larger.• One root with one canal is

normally present.• Double root canal may be

present at apex.• 2 distinct pulp horns are

present.

MAXILLARY CANINE• It has largest pulp chamber of any

single rooted teeth.• Chamber is triangular in shape with

apex towards single cusp & a broad base in cervical third of crown.

• Only one pulp horn is present corresponding to one cusp.

• Single root canal is larger when compared to incisors.

• Canal is wider labiopalatally & on reaching middle third it tapers gradually to an apical constriction.

MANDIBULAR CANINE• Pulp chamber is narrower than

of maxillary canine.• Only one pulp horn is present.• No distinct demarcation is

present between pulp chamber & root canal.

• It has usually 1 canal exiting in 1 apical foramen.