Lecture 7 (Canines) PDF

‫بسم الله الرحمن‬ ‫الرحيم‬  Canines Also called : cuspid: (because they have 1 cusp) Each cusp has 2 cusp slopes (or cusp ridges) : Mesial and distal  - There are two maxillary and two mandibular -canines. They are called corner stone of the mouth. - It has longest root for g...

‫بسم الله الرحمن‬ ‫الرحيم‬  Canines Also called : cuspid: (because they have 1 cusp) Each cusp has 2 cusp slopes (or cusp ridges) : Mesial and distal  - There are two maxillary and two mandibular -canines. They are called corner stone of the mouth. - It has longest root for good anchorage in the bone. - The middle labial lobe is well developed forming cusp and labial ridge. - The bone ridge over the labial surface of the root is called canine eminence (insure facial expression). Upper (maxillary) canine Chronology Appearance of the dental organ 6 m.i.u First evidence of calcification 4-5 months. Enamel completed 6-7 years Eruption 11-12 years Root completed 14- 15 years Type and function This tooth has the function of holding and tearing food as well as esthetic. No. of lobes Relation The upper canine make contact mesially with the distal surface of the lateral incisors and distally with the mesial surface of the 1st premolar. 4 3 2 2 3 4  No. of surfaces It has four surfaces and incisal aspect. Labial Lingual Mesial Dista l No. of roots It has one root. Incisal  Labial aspect ☻Geometrical outline of the crown: Trapezoid -The short side cervically. -The long side incisally. or pentagonal. ☻The outline: - Mesial outline starting from cervical line convex till the junction of middle and incisal thirds ( contact area). Then become concave till outline - The distal cusp tip. is concave till the middle third (the contact area) then convex to the cusp tip. - The cervical line is convex root-  - The distal slope is longer than the mesial slope. ☻Surface anatomy: -The surface is convex both mesiodistally and inciso- cervically. Elevations - Cervical ridge. - Labial ridge. - Cusp. Depressions - Two developmental ☻The grooves. root: - It is long, slender, conical in shape with distal curvature of the apical 3rd.  Lingual aspect - It has the same geometrical outline and outline as the labial surface. - The mesial and distal sides of the crown and root converge ☻Surface lingually. The elevations: anatomy: - The cingulum. - The marginal ridges (mesial and distal). - The lingual ridge. - Mesio and disto-incisal ridges. The depressions - Two lingual fossae. Enumerate the names of the following elevations and depressions? Lingual ridge Cingulu Distal m. Mesial marginal marginal ridge D.L.F M.L.F ridge. D.I.Ridge M.I.Ridge  Mesial aspect ☻Geometrical outline of the crown: ☻Triangular in shape; the base cervically and the apex incisally. ☻The cusp tip may be on a line that bisects the centre of the root or slightly labial ☻The to it. outline: ☻The labial outline is convex with the greatest convexity at cervical 1/3 ☻The lingual ( cervical outline is convex ridge). at cervical 1/3 (cingulum). - Then straight at the middle 3rd and convex at incisal 3rd. ☻The mesial cervical line is concave. ☻Surface anatomy: ☻The mesial surface is convex with the maximum convexity at the junction of the incisal and middle 1/3s ( the contact area). ☻The root: - The root is broad and taper to blunt apex. - It has a mesial developmental depression.  The distal ☻Similar toaspect the mesial aspect but differ in. - The cervical line curvature is less than mesial ( by 1 mm). -The contact area is broader and located at the middle 1/3 (more cervially). - The developmental depression of the root is more developed.  Incisal aspect Labial - The labio-lingual diameter is greater than the mesio-distal diameter. - The cusp tip is slightly M D labial and mesial to the center of the crown. - The distal slope is longer than the mesial slope. Lingua l - All elevations and depressions can be seen from this aspect. Enumerate the names of the following elevations and depressions? Cervical Cusp tip. ridgr. Labial ridge. M. slope. D. slope. Lingual ridge. M.M.R D.M.R Lingual Cingulum. fossae.  ☻Pulp cavity ►Mesio-distal section - Has narrow pulp chamber. - The root canal is long and tapering down to the apical foramen. ►Labio-lingual section - The pulp chamber is pointed incisally. - The root canal start cervically wide till about the middle then ►cervical cross narrows to the apical foramen. section Lower (mandibular) canines Chronology Appearance of the dental organ 6 m.i.u First evidence of calcification 4-5 months. Enamel completed 6-7 years Eruption 9- 10 years Root completed 12- 13 years Type and function This tooth has the function of holding and tearing food as well as esthetic. No. of lobes Relation The lower canine make contact mesially with the distal surface of the lateral incisors and distally with the mesial surface of the 1st premolar. 4 3 2 2 3 4  -Similarto upper canine in the wedge shape but with longer crown ,shorter root & less mesiodistal dimentions. Labial aspect Geometrical outline of the crown: Trapezoid. -The short side -The long side cervically. ☻The outline: incisally. - Mesial outline Is straight with the mesial outline of the root. The mesial contact area is at the incisal 3rd near -the mesioincisal The angle. distal outline is convex till the contact area which is more cervical than the mesial contact area.  - The distal slope is longer than the mesial slope. ☻Surface anatomy: -The surface is convex both mesiodistally and inciso- cervically. Elevations - Cervical ridge. - Labial ridge. - Cusp. Depressions - Two developmental ☻The grooves. root: - It is shorter than upper 3, slender, conical in shape with distal curvature at the apical 3rd & more  Lingual aspect - It has the same geometrical outline and outline as the labial surface. - The mesial and distal sides of the crown and root converge lingually. ☻Surface anatomy: -Flatter, smoother & regular The elevations: (poorly -developed) The cingulum. - The marginal ridges (mesial and distal). - The lingual ridge. - Mesio and disto-incisal ridges. The depressions - one lingual fossa. Enumerate the names of the following elevations Mesio-incisal and depressions? R. Disto-incisal Lingual R. ridge Lingual Distal fossa Mesial marginal marginal ridge ridge Cingulum  Mesial aspect ☻Geometrical outline of the crown: ☻Triangular in shape; the base cervically and the apex incisally. ☻The cusp tip may be on a line that bisects the centre of the root or slightly lingual to it. ☻The ☻The labial outline is less curved outline: with the greatest convexity at cervical 1/3 ( cervical ridge). ☻The lingual outline is also less curved. The cingulum is less pronouced & the incisal portion is thinner labiolingually. - Then concave at the middle 3rd and convex at incisal 3rd.  ☻The mesial cervical line is concave. ☻Surface anatomy: ☻The mesial surface is convex with the maximum convexity at the incisal third ( the contact area). ☻The root: - The root is broad and taper to blunt apex. -It is common to find bifid root (bifurcated) into labial & lingual. Bifid root rarely occurs - Itlower in has acentral more pronounced incisor. mesial developmental depression than the maxillary  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 is broader more cervially located. - The developmental depression of the root is more developed.  Incisal aspect Labial - The labio-lingual dimension is greater than the mesio-distal dimension. - The cusp tip is slightly lingual and mesial to the center of the crown. M D - The distal slope is longer than the mesial slope. -The mesial cusp ridge inclines Lingua lingually. l - The cingulum is slightly distally -shifted. All elevations and depressions can be seen from thi aspect. Enumerate the names of the following elevations and depressions? Cervical ridge. Cusp tip. Labial ridge. D. slope. M. slope. D.M.R M.M.R Cingulum. Lingual Lingual fossa. ridge.  Pulp cavity Mesiodistal section Labiolingual section Transvers e section Identify the tooth and the aspect then tell THE differences. Answer A is upper A B is lower canine canine. Lingual aspect 1- The width in relation to the 2- The elevations and length. the depression. 3- The cusp. 4-The cusp slopes. 5- contact areas. B 6- The root.