Permanent Anterior Teeth PDF

Permanent Anterior Teeth Dental Anatomy I (DAN 111) Prof. Amel M. Ezzat Abd-El-Hamied The ideal way to describe a tooth It is easier to follow these steps: - Chronology (i.e. dates of events for each tooth as enamel organ appearance, beginning of calcification, crown completed, er...

Permanent Anterior Teeth Dental Anatomy I (DAN 111) Prof. Amel M. Ezzat Abd-El-Hamied The ideal way to describe a tooth It is easier to follow these steps: - Chronology (i.e. dates of events for each tooth as enamel organ appearance, beginning of calcification, crown completed, eruption and root completed). - Type ( anterior or posterior) and function (incising, holding or grinding …… etc.). - No. of lobes. - Relations (contact with which tooth mesial and distally). - No. of surfaces. - No. of root(s).  To describe each tooth aspect the student should follow the following: ►Geometric outline. Trapezoid Rhomboid Triangle ►Outline. Straight Convex Concave ►Surface anatomy. Elevations and depressions present on the surface. ►Root curvature. ►Pulp cavity. - No. of pulp horns, shape of pulp chamber and no. of root canal(s).  Maxillary Permanent Incisors ☻There are 4 maxillary incisors. 2 per each quadrant. 1 1 2 2 ☻2 central incisors contact each other at the midline. ☻2 lateral incisors distal to the central incisor.  Maxillary permanent central incisor  Maxillary Central Permanent Incisor ☻There are 2 central incisors in upper jaw. ☻The upper central incisor is the most broadest tooth of the anterior teeth. To describe the general characteristics of the maxillary permanent central incisor we have to follow the previous steps: Chronology Appearance of the dental organ 5m.i.u First evidence of calcification 3-4 months Enamel completed 4-5 years Eruption 7-8 years Root completed 10 years Type and function This tooth has the function of incising food as well as esthetic. No. of lobes It has four lobes (three mamelons and cingulum) Relation The two central incisors make contact mesially with each other and distally with the mesial surface of the lateral incisor. 2 1 1 2 No. of surfaces It has four surfaces and incisal aspect. Labial Lingual Mesial Distal Incisal No. of roots It has one root.  Surface Anatomy Labial aspect ☻Geometrical outline of the crown: Trapezoid -The short side cervically -The long side incisally ☻The outline: - Mesial outline is slightly convex. D M - Distal outline is more convex. - Incisal outline is straight and perpendicular to the long axis of the tooth. - The cervical line is convex root-wards.  - The mesio-incisal angle is sharp. - The disto-incisal angle is rounded. ☻Surface anatomy: -The surface is smoothly convex, it is flattened incisally. Two shallow D.D divide the labial surface into 3 portions of lobes -Cervical ridge located at cervical third. D.I M.I angle ☻The root: angle - It has a single root. - It is cone shape with blunt apex. - It has the same geometrical outline and outline as the labial surface. Lingual aspect - The mesial and distal sides of the crown and root converge lingually ( the lingual surface is narrower than the labial surface). M D - This convergence to accommodate with the horse shoe shape of the alveolar process. The facial surface is larger than the lingual surface. ☻Surface anatomy: The elevations: 1- The cingulum ( present at cervical 1/3. 2- Marginal ridges.(well developed MMR and DMR ) 3- Incisal ridge. The depressions: - The lingual fossa ( it lies between the previous elevations).  Mesial aspect ☻Geometrical outline of the crown: ☻Triangular in shape; the base cervically and the apex incisally. ☻The incisal ridge is on a line that bisects the centre of the root. ☻The outline: ☻The labial outline is convex at cervical 1/3 ( cervical ridge). -Then become flat to the incisal ridge. ☻The lingual outline is convex at cervical 1/3 (cingulum). - Then concave at the lingual fossa. - Then slightly convex for the incisal ridge. ☻The mesial cervical curvature is convex incisally. It is greater than any other tooth in the mouth. ☻Surface anatomy: ☻The mesial surface is convex with the maximum convexity at the incisal 1/3 ( the mesial contact area) ☻The root: ☻It is cone shape with blunt apex.  The distal aspect ☻Similar to the mesial aspect but differ in: -The cervical line curvature is less than mesial ( by 1 mm). -The contact area located at the junction of incisal and middle 1/3s.(the distal contact area)  Incisal aspect ☻Triangular in shape. The base is placed labially and the - apex lingually. M-D>lab-ling- ☻ The labial surface is broad and flat. The cervical portion of the crown is convex ( cervical ridge). ☻The lingual outline tapers lingually to the cingulum (lingual convergence). - The cingulum is centralized. ☻Pulp cavity ►Mesio-distal section - The pulp chamber is wide conforming the shape of the crown. - It presents three pulp horns corresponding to the three mamelons. - The root canal tapers towards the apex. ►Labio-lingual section - The pulp chamber - The root canal tapers gradually pointed incisally, then as it traverse the root ending in a follows the increase in constriction at the apex (the the crown dimension apical foramen). cervically.  Maxillary permanent lateral incisor Chronology Appearance of the dental organ 5 m.i.u First evidence of calcification 1 year Enamel completed 4-5 years Eruption 8-9 years Root completed 11 years Type and function This tooth has the function of incising food as well as esthetic. No. of lobes It has four lobes (three mamelons and cingulum) Relation The lateral incisor make contact mesially with the central incisor and distally with the mesial surface of the canine. 3 2 2 3 No. of surfaces It has four surfaces and incisal aspect. Labial Lingual Mesial Distal No. of roots It has one root. Incisal  Surface Anatomy Labial aspect ☻Geometrical outline of the crown: Trapezoid -The short side cervically -The long side incisally ☻The outline: - Mesial outline is slightly convex. -Distal outline is more convex. M D -Cervical outline is convex toward the root. -MCA is at junction of incisal and middle thirds. -DCA is in the center of middle 1/3. - Incisal outline is curved. (why?) -The mesio-incisal angle is rounded. -The disto-incisal angle is more rounded ☻Surface anatomy: -The surface is more convex than the central incisor. -Cervical ridge located at cervical third. D M ☻The root: - It has a single root narrower and longer than in 1. - It tapers evenly to apical 1/3 , then curve distally with a pointed apex. - It has the same geometrical outline and outline as the labial surface. Lingual aspect - The mesial and distal sides of the crown and root converge lingually ( the lingual surface is narrower than the labial surface). M D - This convergence to accommodate with the horse shoe shape of the alveolar process. ☻Surface anatomy: The elevations: 1- The cingulum ( present at cervical 1/3). 2- Marginal ridges: - Mesial marginal ridge. - Distal marginal ridge. 3- Incisal ridge. The depressions: - The lingual fossa ( it lies between the previous elevations). - Notice the lingual pit. ☻All elevations and depression are more developed than the upper central incisor.  Mesial aspect ☻Geometrical outline of the crown: ☻Triangular in shape; the base cervically and the apex incisally. ☻The incisal ridge is on a line that bisects the centre of the root. ☻The outline: ☻The labial outline is convex at cervical 1/3 ( cervical ridge). -Then become slightly convex to the incisal ridge. ☻The lingual outline is convex at cervical 1/3 (cingulum). - Then concave at the lingual fossa. - Then slightly convex for the incisal ridge. ☻The mesial cervical line is concave towards the root. ☻Surface anatomy: ☻The incisal portion is thicker than in 1 and on a line with the center of the root. MCA is at junction of incisal and middle 1/3s ☻The root: ☻It is cone shape with blunt apex. It has developmental depression.  The distal aspect ☻Similar to the mesial aspect but differ in: - The cervical line curvature is less than mesial ( by 1 mm). -The contact area located at the middle 1/3 (more cervially).  Incisal aspect ☻It may resemble the central incisor ☻The labio-lingual dimension is greater in comparison to the central incisor. The incisal outline is more rounded. ☻The cingulum is centered.  Malformations Of The Upper Permanent Lateral Incisor 3 1 Missing lateral Peg-shaped incisor. lateral incisor. ☻Pulp cavity ►Mesio-distal section - The pulp chamber is wide conforming the shape of the crown. - It has two pulp horns only. - The root canal tapers towards the apex. ►Labio-lingual section - The pulp chamber - The root canal tapers gradually pointed incisally, then as it traverse the root ending in a follows the increase in constriction at the apex (the the crown dimension apical foramen). cervically. THANK YOU