Dental Anatomy1 OBD 111 Introduction-2 PDF 2025

 faculty of dentistry Oral biology department Dental Anatomy1 OBD 111 Introduction-2 DR/ Eman Salem Lecturer of oral biology department PUA Line angles...

 faculty of dentistry Oral biology department Dental Anatomy1 OBD 111 Introduction-2 DR/ Eman Salem Lecturer of oral biology department PUA Line angles mesial Formed by junction of (two) surface lingual Mesio-buccal Distal line angel Mesio-libial line angel Point angle formed by the junction of (three) surface distal labial mesial incisal Mesio-libio-incisal Mesio-lingo-incisal Point angel Point angel Division in thirds of the tooth crown and root viewed from labial aspect, in horizontal and vertical directions. from proximal, in a vertical direction. Divisions Into Thirds Anatomical Landmarks Of The Crown Elevated Landmarks: Depressed Landmarks: 1- Dental lobe 1- Developmental grooves A- mamelon 2- Supplemental grooves B-cingulum 3- Fissures C- cusp 4- Sulcus 2- Tubercle 5- Fossa 3- Ridges 6- Pit Elevations 1-Lobes A lobe is one of the primary sections of formation in the development of the crown. * The cingulum, cusps and mamelons are representatives of lobes. Mamelon It is any one of the three rounded protuberances found on the incisal ridge of a newly erupted incisor tooth. Cingulum It is the lingual lobe of an anterior tooth it makes up the bulk of cervical third. Cusp It is a divisional primary elevation on the occlusal third of posterior teeth, and incisal third of canines. Tubercle It is a smaller elevation on some portion of the crown produced by excessive localized deposition of enamel. Ridges: A ridge is a linear elevation of the surface of the tooth, and is named according to its shape or location.. Marginal ridge Oblique ridge Cervical ridge  1- Marginal ridge linear elevation which forms the mesial and distal margins of the occlusal surfaces of posterior teeth and the lingual surfaces of the anterior teeth. 2- Triangular ridge linear elevation which extends from the tip of the cusp toward the central portion of the occlusal surface of a posterior tooth. It is named for the cusp to which it belongs. 3- Transverse ridge: made up of the union of two triangular ridges transversely. 4- Oblique ridge: made up of the union of two triangular ridges obliquely. 5- Cusp ridge: It is a linear elevation which extends in a mesial and distal directions from the cusp tip 6- Cervical ridge: Linear elevation on the cervical third of the buccal surface of premolars and molars 7- Labial ridge: It is a linear elevation made by the middle lobe of the labial surface of canines. 8- Buccal ridge: It is a linear elevation made by the middle lobe of the buccal surface of premolars. 9- Lingual ridge: It is a linear elevation on the lingual surface of canines extending from the cingulum to the cusp tip. 10- Incisal ridge: It is a linear elevation made by the incisal portion of a newly erupted anterior tooth.  Depressed Landmarks 1-Developmental Groove It is a deep 2-Supplemental groove It is a shallow linear depression in the occlusal surface linear depression on the occlusal surface and may extend buccally, lingually or which does not demarcate the line of lobe mesially indicating the line of fusion of fusion, but represents a Branch from the primary lobes. developmental groove. Supplemental groove 3-Sulcus It is a long tent shaped space or valley on the occlusal surface running between the cusps and its inclined surfaces meeting centrally 4-Fissure It is a deep cleft or defect on the occlusal or buccal surfaces resulting from linear imperfect fusion of enamel found in the place of developmental grooves.  5-Fossa It is a small depression or concavity on the lingual surface of anterior teeth and occlusal surfaces of posterior teeth. Central fossa, : A relatively broad, deep angular valley in the central portion of the occlusal surface of a mandibular molar. Lingual fossa: a broad, shallow Triangular fossa: A shallow pyramid shaped depression on the lingual surface of depression on the occlusal surface of the an incisor or canine. posterior' teeth.  Notation systems These are the systems designed to identify the type of each tooth and its location in each quadrant of the dental arches. Some of these systems are more commonly used in certain countries than the others. I - Palmer notation system II - The two digit system or FDI system FDI system (Federation Dentaire Internationale) III- The Universal Notation System I - Palmer notation system This system is based on denominating the teeth in each quadrant of the dental arches. The deciduous teeth are given the letters A through E beginning with the 1st incisor and ending with the last molar for each quadrant. The permanent teeth are given the numbers 1 through 8, again beginning with the 1st incisor and ending with the last molar for each quadrant. II - The two digit system or FDI system FDI system (Federation Dentaire International) The first digit of this system is based on the numbering of the four quadrants of the dental arches in a clockwise direction starting with the right maxillary quadrant and ending with the right mandibular quadrant. The numbering of the quadrants is a) 1 through 4 for the permanent dentition. b) 5 through 8 for the deciduous dentition. 41 → right mandibular permanent incisor 81 → right mandibular deciduous incisor III- The Universal Notation System # the median line of the cross is not used as a starting point and the first letter (A) or the first number (1) are not given to the first incisor. Instead, the letter (A) is given to the right maxillary second deciduous molar and the first number (1) is given to the right maxillary permanent third molar. 11= left maxillary permanent canine 32=right mandibular permanent third molar A =right maxillary deciduous second molar K =left mandibular deciduous second molar