2. GENERAL CHARACTERISTICS OF PRIMARY ANTERIOR TEETH Smaller in size than the analogous secondary teeth Whiter in color Crowns and roots of primary teeth have a marked constriction at the cervix Labial cervical ridges more prominent than in permanent teeth No mamelons on the incisal edges upon eruption Roots are longer and narrower MD
3. MANDIBULAR TEMPORARY CENTRAL INCISOR LABIAL Flat surface with no developmental grooves Mesial and distal sides of the crown are tapered evenly from the contact areas towards the cervix Compared to permanent mandibular CI: MD measurement is smaller Lali measurement same
4. MANDIBULAR TEMPORARY CENTRAL INCISOR LABIAL Crown is wide in proportion to its length Resembles the permanent maxillary lateral incisor Root is long and tapers evenly to the apex Root is pointed and almost twice the length of the crown
5. MANDIBULAR TEMPORARY CENTRAL INCISOR LINGUAL Middle and incisal thirds may have a flattened surface level with the marginal ridges or may have a lingual fossa Has prominent cingulum slight lingual fossa and faint marginal ridges Crown and root converge lingually
6. MANDIBULAR TEMPORARY CENTRAL INCISOR LINGUAL Tooth is narrower lingually Crown and root converge lingually Tooth is narrower lingually
7. MANDIBULAR TEMPORARY CENTRAL INCISOR MESIAL Cervial line more curved than in distal aspect Incsal ridge centered on the root axis line Convexity of the cervical contours labially and lingually at the cervical third is pronounced Shows a prominent labial cervical ridge
8. MANDIBULAR TEMPORARY CENTRAL INCISOR MESIAL Crowns are wide Lali due to large cingulum Lali measurement is only about a millimiter less than that of the primary maxillary central incisor Root is nearly flat and evenly tapered Root apex more blunt compared to labial and lingual aspects
9. MANDIBULAR TEMPORARY CENTRAL INCISOR DISTAL Cervical line of the crown is less curved Developmental depression frequently evident on the distal side of root
10. MANDIBULAR TEMPORARY CENTRAL INCISOR INCISAL Incisal ridge is straight and bisects the crown Lali Labial surface presents a flat surface slightly convex Lingual surface presents a flat surface slightly concave
11. MANDIBULAR TEMPORARY CENTRAL INCISOR INCISAL Has essentially equal MD and Lali dimensions with temporary mandibular lateral incisor Crown tapers towards the cingulum on the lingual side
14. Temporary Mandibular Canines Labial Aspect Crowns are longer inciso-cervically than wide mesiodistally. Sharp cusp tips like an arrow. Roots are more tapered and pointed. Roots shorter than temporary maxillary canines. Cervical third of proximal crown margins do not converge cervically.
15. Temporary Mandibular Canines Labial Aspect No grooves on labial surface. No style on incisal margins. M & D heights of contour are much nearer the cervix. Labial surface is convex in all directions. Three lobes Central lobe Mesial lobe Distal lobe
16. Temporary Mandibular Canines Lingual Aspect Cingulum reduced in size and less prominent. Cingulum occupies less than the cervical third of the height of crown. Lingual ridges barely discernible. Faint marginal ridges. Single concavity or fossa. Cingulum narrow in mesiodistal direction.
17. Mesial and distal view Cervical ridges are prominent cusp tip is most often located slightly lingual to the root axis line. The cervical third of a primary canine is much thicker than incisor. Cervical lines curve incisally more on the mesial side than on the distal side The roots are bulky in the cervical and middle thirds, tapering mostly in the apical third where the apex is bent labially
18. Temporary Mandibular Canines Mesial Labial Border slightly concave The border is divergent from the long axis of tooth and extends from the mesio-incisal angle to the cervical border Above the cervical border,the curvature increases as it rounds into the cervial constriction Lingual Border convex and then moderately concave before it enters into the convex cingulum.
20. Temporary Mandibular Canines Mesial Surface Cervical Border is evenly concave toward the root Mesial surface of the crown is convex in the incisal 2/3 Can be flatten or even become concave toward the center of the surface above the cervical line
21. Temporary Mandibular Canines Distal surface Cervical border Evenly concave toward the root Of the crown More extensive than the mesial surface Evenly convex
22. Temporary Mandibular Canines Distal surface Labial border Moderately concave And becomes convex above the cervical constriction Lingual border Firstly convex at the short distance Then concave and convex again Influenced by the cingulum
23. Temporary Mandibular Canines Incisal Crown outline: diamond- shaped nearly symmetrical, except for the mesial position of the cusp tips more bulky in the distal half Crown is 0.4 mm wider MD than Lali Cingulum centered or just distal to the center Actual tooth Cast
Notes de l'éditeur
2. Whereas in permanent mandibular canines, mesial cusp slope is shorter that distal cusp slope.