Tooth Morphology PDF

Tooth Morphology RAYNAND M. DIMAANO, DMD OLFU, COLLEGE OF DENTISTRY  THE CROWN AND ROOT Apex of Root ★ CROWN○ Portion of the tooth covered with enamel ★ Root ROOT ○ Portion of the tooth covered with cementum...

Tooth Morphology RAYNAND M. DIMAANO, DMD OLFU, COLLEGE OF DENTISTRY  THE CROWN AND ROOT Apex of Root ★ CROWN○ Portion of the tooth covered with enamel ★ Root ROOT ○ Portion of the tooth covered with cementum Cervical Line ○ Can be mono-rooted, bi-rooted (2), multi-rooted (3 roots) Crown Incisal Edge 2  THE CROWN AND ROOT ★ ○ Portion of the tooth CROWN covered with enamel ★ ROOT ○ Portion of the tooth covered with cementum ○ Can be mono-rooted, bi-rooted (2), multi-rooted (3 roots) 3 FOUR MAJOR TISSUES OF A TOOTH *Enamel, Dentin, and Cementum are HARD TISSUE S *Pulp is a SOFT TISSUE 4  ENAMEL Is the white, protective external surface layer of the anatomic crown It is highly calcified or mineralized Hardest substance in the body It develops from enamel the organ (ectoderm) A product of specialized epithelial cells ameloblasts called 5  DENTIN Is the hard yellowish tissue underlying the enamel and cementum Makes up the major bulk of the inner portion of each tooth crown and root Develops from the embryonic dental papilla (mesoderm) The cells that form dentin are called odontoblast Mineral content: ★ 70% calcium hydroxyapatite ★ 18% organic matter (collagen fibers) ★ 12% water 6  DENTINOENAMEL JUNCTION CEMENTODENTINAL JUNCTION DEJ- is the inner surface of the enamel cap where enamel joins dentin CDJ- is the inner surface of cementum where cementum joins dentin 7  CEMENTUM Is the dull yellow external layer of the tooth root Is very thin, especially next to the cervical line It develops from the dental sac (mesoderm) Is produced by cells called cementoblasts Mineral content: ★ 65% calcium hydroxyapatite (mineralized and calcified) fibers) ★ 35% organic matter (collagen ★ 12% water 8  CEMENTOENAMEL JUNCTION Separates the enamel of the crown from the cementum of the anatomic root This junction is also known as the cervical line, denoting that it surrounds the neck or cervix of the tooth 9  PULP Is the soft tissue in the cavity or space in the center of the crown and root called the pulp cavity It develops from the dental papilla (mesoderm) 10  PULP Pulp Chamber - cavity which contains the coronal pulp Coronal Pulp - located in the crown area Root Canal - contains radicular the pulp Radicular Pulp - pulp in root area the 11 DENTAL PULP 12  FUNCTIONS OF THE DENTAL PULP Formative : secondary dentin Sensory : Nerve endingsrelay the sense of pain Nutritive : Defensive or protective reparative dentin 13  APEX Anatomic area at the tip / end of the root 14  APICAL FORAMEN The opening at the apex of the root of a tooth, through which the nerve and blood vessels that supply the dental pulp pass 15  CLINICAL AND ANATOMICAL CROWN AND ROOT The anatomic crown is that part of the tooth normally covered by an enamel layer, and the anatomic root is the part of a tooth covered by cementum The clinical crown refers specifically to the amount of tooth visible in the oral cavity, and the clinical root amount of referstooth to thethat isnot visible since it is covered with gingiva 16 CLINICAL AND ANATOMICAL CROWN 17 CLINICAL AND ANATOMICAL CROWN AND ROOT 18  PERIODONTIUM Is defined as the supporting tissues of the teeth in the mouth, including surrounding alveolarbone, the gingiva,the periodontal ligament, and cementum the outer, layertoothofroots the ALVEOLAR BONE- the portion of the upper or (maxillary) lower (mandibular) bones that surrounds the roots of the teeth 19  GINGIVA Is the part of the soft tissue in the covers the mouth alveolarthat bone of the jaws 20 FREE GINGIVA/ MARGINAL GINGIVA AND GINGIVAL SULCUS A collar of thin gingiva that surrounds each tooth and, in health, adapts to the tooth but provides access into the potential space between the free gingiva and the tooth which is called gingival asulcus (crevice) 21  ATTACHED GINGIVA Firmly bound to the underlying alveolar bone The portion of the gingiva extending from the gingival margin to the alveolar mucosa 22  INTERDENTAL/ INTERPROXIMAL PAPILLA Part of the collar of free gingiva that extends between the teeth. 23  PERIODONTAL LIGAMENT Is a very thin ligament composed of many tissue fibers that attach the outer layer of the tooth root to the thin layer of dense alveolar bone surrounding each tooth 24 DIVISIONS INTO THIRDS 25 DIVISIONS INTO LINE ANGLES ANTERIOR Order of naming: Mesial Distal Facial- labial/buccal Lingual Occlusal/ incisal Change the “al” ending of the first surface to “o” 2 6 DIVISIONS INTO LINE ANGLES POSTERIOR 27 DIVISIONS INTO POINT ANGLES 28 DIVISIONS INTO POINT ANGLES 29 MORPHOLOGY OF AN ANATOMIC CROWN 30  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) CUSP A pyramidal elevation,or peak, located on the occlusal surfaces of molars and premolars, and on the incisal edges of canines 31 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) CUSP A pyramidal elevation,or peak, located on the occlusal surfaces of molars and premolars, and on the incisal edges of canines 32 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) TUBERCLE A small elevation on some portion of thecrown produced by an extra formation of enamel 33 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) CUSP RIDGES Each cusp has four cusp ridges (linear prominences of enamel) converging toward the cusp tip. These four ridges form the shape of a four-sided, somewhat rounded pyramid 34 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) MESIAL AND DISTAL CUSP RIDGES Cusp slopes or cusp arms Inclined surfaces or slopes that converge toward the cusp tip to form an angle 35 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) MARGINAL RIDGES (ANTERIOR) Located on the mesial and distal border of the lingual surface and converge toward the cingulum 36 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) MARGINAL RIDGES (POSTERIOR) Located on the mesial and distal borders of the occlusal surface 37 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) TRIANGULAR RIDGE Are located on each major cusp of posterior teeth. Each triangular ridge extends from a cusp tip toward the depression (sulcus) in the middle of the occlusal surface faciolingually 38 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) TRANSVERSE AND OBLIQUE RIDGE When a triangular ridge from a facial cusp joins with a triangular ridge from an adjacent lingual cusp, the two ridges together form a longer ridge= Transverse Ridge Oblique ridge is found only onmaxillary molars It crosses the occlusal surface obliquely and is made up of one ridge on the mesiolingual cusp joining with the triangular ridge of the distobuccal cusp 39 Dr. PDLigon 1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) TRANSVERSE AND OBLIQUE RIDGE 40 Dr. PDLigon. BUCCAL CUSP RIDGE AND LABIAL RIDGE Buccal cusp ridge is a subtle ridge running cervicoocclusally in the middle third of the buccal surface of premolars The labial ridge runs cervicoincisally and can be very prominent on maxillary canines 41 Dr. PDLigon  CROWN OUTLINE AND OCCLUSAL TABLE Crown outline is the outline of the entire tooth crown from the occlusal view Occlusal table is the outline of the smaller occlusal surface that is bounded by adjoining mesial and distal cusp ridges and marginal ridges that surround it 42 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) CINGULUM Is the enlargement or bulge on the cervical third of the lingual surface of the crown on anterior teeth 43 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) CERVICAL RIDGE On the facial surface of permanent molars (and all primary teeth), the subtle ridge running mesiodistally in the cervical one third of the facial surface of a crown It is most pronounced on the outline of the mesiobuccal cusp of mandibular second molars 44 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) MAMELONS Are three small tubercles or scallops, each formed from one of the three facial developmental lobes on the incisal newly edges erupted of incisors 45 Dr. PDLigon  1. ELEVATIONS (ROUNDED) AND RIDGES (LINEAR) PERIKYMATA Are the numerous, minute horizontal ridges on the enamel of newly erupted permanent teeth 46 Dr. PDLigon 2. DEPRESSION AND GROOVES SULCUS A broad V-shaped depression or valley running mesiodistally on the occlusal surfaces of posterior teeth Grooves and their sulci are important escape-ways for morsels when the teeth of the lower jaw move from side tofood side and protrude forward against the upper teeth during chewing 47 Dr. PDLigon 2. DEPRESSION AND GROOVES DEVELOPMENTAL GROOVES Are the major, sharply defined narrow, linear depressions formed during tooth development and usually separating the lobes or major portions of a tooth 48 Dr. PDLigon 2. DEPRESSION AND GROOVES FISSURE Is a very narrow cleft or crevice at the depth of any groove, caused by the incomplete fusion of enamel during tooth development 49 Dr. PDLigon 2. DEPRESSION AND GROOVES FOSSA A small hollow or depression found between the marginal ridges on the lingual surfaces of anterior teeth particularly maxillary incisors and at specific locations on the occlusal surfaces of posterior teeth 50 Dr. PDLigon 2. DEPRESSION AND GROOVES TRIANGULAR FOSSA Found on molars and premolars on the occlusal surfaces mesial or distal to marginal ridges 51 Dr. PDLigon 2. DEPRESSION AND GROOVES PITS Often occur at the depth of a fossa where two or more grooves join 52 Dr. PDLigon EXTERNAL MORPHOLOGY OF THE ANATOMIC ROOT 53 Dr. PDLigon  ANATOMIC ROOT The part of a tooth that is covered with cementum Is the tip or peak at the end of the APEX root, often with visible openings called apical foramina APICAL Where the nerves and FORAMINA blood vessels enter into the tooth pulp Or neck of the tooth is the slightly CERVIX constricted region of union of the crown and the root 54 Dr. PDLigon  Or trunk base is the part of the root of a ROOT TRUNK multi-rooted molar or two-rooted premolar next to the cementoenamel junction that has not yet split Is the place on multi-rooted teeth where the root FURCATION trunk divides into separate roots Bifurcation on two-rooted teeth Trifurcation on three-rooted teeth FURCAL REGION Or interradicular space is the region or space between two or more roots, apical to the place where the roots divide from the root trunk 55 Dr. PDLigon CERVICAL LINE (CEJ) CURVATURE 56 Dr. PDLigon  CERVICAL LINE (CEJ) CURVATURE When viewed from the mesial or distal aspect, the cervical line of a tooth curves (is convex) toward the incisal or occlusal surface In general, the amount of curvature is greater on the mesial surface than on the distal surface of the same tooth 57 Dr. PDLigon CERVICAL LINE (CEJ) CURVATURE 58 Dr. PDLigon RELATIVE SIZE 59 Dr. PDLigon  TOOTH DEVELOPMENT FROM LOBES Tooth crowns develop from lobes or primary growth centers As a general rule, the facial portion of incisors, canines and premolars forms from three lobes, and the cingulum area or lingual cusp(s) each form from one lobe 60 Dr. PDLigon TOOTH DEVELOPMENT FROM LOBES 61 Dr. PDLigon TOOTH DEVELOPMENT FROM LOBES 62 Dr. PDLigon THANK YOU! 63 Dr. PDLigon