Anatomical Landmarks of the Crown PDF

5- Anatomical Landmarks of the Crown Crown elevations Lobes Tubercle mamelon Cusp Cingulum Contact area Crown depressions Ridges Facial Labial Buccal Cervical Lingual Fossa Occlusal Marginal Incisal Triangular Lingual Transverse Marginal Oblique Other terms Hight of contour Dr. SAID ABDE...

5- Anatomical Landmarks of the Crown Crown elevations Lobes Tubercle mamelon Cusp Cingulum Contact area Crown depressions Ridges Facial Labial Buccal Cervical Lingual Fossa Occlusal Marginal Incisal Triangular Lingual Transverse Marginal Oblique Other terms Hight of contour Dr. SAID ABDELGHANY /01061999121 Sulcus Developmental groove Supplemental groove Pits Fissure 1-crown elevations 1- Lobe : - It is the primary growth center during the crown development - Teeth are developed from four or more lobes. - Cusps & mamelons & cingulum represent lobes after eruption. Incisors and canines four lobes 3 labial 1 lingual mamelon Cingulum Premolars four lobes except the lower 2nd premolar may be developed from 5 lobes. Each molar cusp developed from one Lobe Example: the mandibular first molar (lower 6 ) has five cusps & is developed from 5 lobes. 2- Mamelon - They are three small round projections present in the incisal third of newly erupted incisors - After normal use, eventually the mamelons wear down into a flat edge - present in permanent incisors only not in the canine. - Deciduous hasn’t mamelons or cingulum. 3- cingulum It is enlargement on the cervical third of the lingual surface of the crown of anterior teeth ( 4th lobe ) . 4- Tubercle: - It is a small elevation produced by an extra formation of enamel. - It is commonly seen on the palatal surface of maxillary incisors adjacent to the cingulum and also in upper 6 ( tubercle of Carabelli ) + upper E. 5- Cusps - They are conical or pyramidal elevations. - Presents on the occlusal surface of the posterior teeth (premolars and molars) And on the incisal portion of the canine. - Each cup is named according to its location on the tooth. Cusp Enamel ‫جزء اساسي من السنه ليها‬ Dentine ‫و‬ Tubercle ‫ فوق تكوين السنه‬Enamel ‫جزء زايد من تكوين‬ .‫يعني مش من اصل السنه‬ ‫فقط‬Enamel 6- Ridge : It is a linear elevation on the different surfaces of the crown named according to its location According to location Facial surface 1labial ridge - Runs cervico-incisally on the labial surface of anterior teeth - It is most prominent in the maxillary teeth. 2- buccal ridge - Runs cervicoocclusally on the buccal surface of posterior teeth - It is most prominent in premolars. 3- Cervical Ridge Runs mesio-distally on cervical third of the facial surface of all teeth Lingual surface 1- incisal ridge - it turns into incisl edge with time 2- lingual ridge - In canine dividing lingual fossa into 2 fossae 3- Marginal Ridge - It is a linear round elevation which terminates on the mesial and distal borders of the lingual surface on anterior teeth. Cusp ridge Each cusp has four ridges . The buccal cusp of lower first premolar has 4 ridges: 1-The mesial ridge 2- The distal ridge 3- The buccal ridge 4- The triangular ridge Occlusal surface 1- Marginal Ridge - On posterior teeth it is located on the mesial and distal borders of the occlusal surface. 2-Triangular ridge - It is located on each cusp of posterior teeth. Each triangular ridge extends from a cusp tip toward the middle of the occlusal surface bucco lingually. 3-Transverse ridge - It is the union of two triangular ridges which cross the occlusal surface of most of the posterior teeth transversely (buccolingually). 4- Oblique ridge - It is union of two triangular ridges which crosses the occlusal surface of maxillary molars obliquely. Triangular ridge According to its shape Transverse ridge Dr. SAID ABDELGHANY / 01061999121 Oblique ridge