DEPARTMENT OF PEDODONTICS & PREVENTIVE DENTISTRY
•Primary teeth are also known as:• Decidues teeth• baby teeth• Milk Teeth• Temporary teeth
• These are 20 total in number 10 in each jaw – maxillary Central incisor – maxillary Lateral incisor – Maxillary Canine – Mandibular Central incisor – Mandibular lateral Incisor – Mandibular Canine – maxillary first Molar – Maxillary Second Molar – Mandibular first Molar - Mandibular Second Molar
Maxilary central incisor• LABIAL ASPECT1. mesiodistal diameter of crown is greater then cervico incisal2. labial surface is smooth3. No development lines seen4. Root length is greater than crown length5. Root is conical with even tapered side
Lingual aspect :-3. Well developed marginal ridges and highly developed cingulam soon4. Cingulam extend up toward incisal ridge to divide lingual surface in mesial, distal fossa5. Root tapers lingually and present a ridge or its full length6. Cross section of root is triangular
mesial and distal aspect: -3. Mesial and distal aspect of primary maxillary central incisor are similar4. The curvature of crevical line which represent cemento enamel junction or distinct curving towards incisal edge5. Curvature distally is less than mesially6. Crown appears thick at middle third
incisal surface• the incisal edge is relatively small• Labial surface appears broad• lingual surface taper towards cingulam• mesial / destal surface are relatively broad• mesial/ Distal surface taper towards incisal
Maxillary lateral incisorSame as maxillary central incisor expect:• crown is samller in all direction• Cervico incisal length of lateral crown is greater than mesio distal• Disto incisal angles are more rounded• Root is much longer in proportion to its crown than central ratio.
Maxillary Canine• Labial aspect :-• The crown is more constricted at cervix in relation to its mesio distal width• Mesio distal srufaces are more covex• incisal edge form long well developed sharp cusp.• Cusp is longer and sharper than permanent teeth• Mesial slope of cusp is longer than distal slope• Root is long, slender, tapering and more than twice in crown length
• Lingual aspect: -• Cingulam, Mesial and distal marginal ridge ound• Lingual ridge divide lingual surface in shallow mesio lingual and distolingual fossa• root tapers lingually• Mesial aspect: -• Outline form is similar to central and lateral incisor• The measurement labio lingually at cervical third is greater
• Distal aspect: -• Distal aspect is similar to medial aspect except that curvature of cervical line towards cusp ridge less than mesial.• Incisal aspect: -• Crown is diamond shaped from this aspect• The tip of the cusp is distal to center of crown• mesial cusp slope is longer than distal cusp slope
Mandibular central incisor• Labial aspect : -• Flat face with no developmental groove• mesial and distal sides of crown are tapered evenly from contact area• Crown is wide in proportion to its length in comparison with that of its permanent successor• the root of primary central incisor is long, evenly tapered dawn to apex
• Lingual aspect : -• Marginal ridges and cingulam may be located easily• Lingual surfae of crown at middle third and incisal third may have a flattened surface or may present with slight concavity• Lingual portion of crown and root converge so that it is more narrow towards the lingual
• mesial aspect: -• Convexity of cerviacal contours at cervical third is prononced• labio lingual measurement of teeth is only a millimeter less tan primary maxillary central incisor• Mesial surface of root is nearly flat and evenly tapered.• Distal aspect: -• Outline of teeth from distal aspect is reverse from mesial aspect• Cervical line of crown is less curved towards incisal ridge than on mesial surface• Developmental deprersion is present on root.
• Incisal aspect: -• Incisal ridge is straight and bisect the crown labio lingually• A definite taper is evident towards the cingulam on lingual side• Labial surface term this view presents a flat surface slightly convex, whereas the lingual surface present a flattened surface slightly concave.
Mandibular lateral incisor• Somewaht larger in all measurement than central incisor• Cingulam is little more genreous than that of central incisor• lingual surface of crown is more concave• Incisal ridge slope downwared distally, this design lowers the distal contact area apically so that proper contact can be made with mesial surface of primary mandibular canine
MANDIBULAR CANINE• Crown is 0.5 mm and root is 2 mm shorter than maxillary canine• mesiodistal measurement of mandibular canine is less when compared to its mesio distal measurement at contact area than maxillary canine• The cervical ridge labially and lingually are not quite as pronounced as those in maxiallary canine
maxillary first Molar• Buccal aspect : -• Widest measurement of crown of maxillary first molar is at contact area mesIally and distally• Crwon converge towards cervix• The occlusal line is slightly scalloped but with no definite Cusp form• Buccal surface is smooth with little evidence of developmental grooves• Smaller than maxillary second molar• Roots are slender and long,
• Lingual aspect: -• the crown converge considerably in a lingual direction making the lingual portion calibrate less mesiodistally than buccal protion• Mesiolingual cusp is most prominent, longest and sharpest cusp.• Distolingual cusp is poorly defined• all three roots are seen• Lingual root is larger than other
• Mesial aspect: -• Dimension of cervical third is greater than demension of occlusal third• A pronounced concavity is evident on buccal outline of cervical third• Cervical line measlally showns some curvature in direction of occlusal surface• A pronounced convexity is evident on the buccal outline of cervical third• Mesiobuccal and lingual roots are visibal only when looking at the mesial side• Lingual root from this aspect look long and slender and extend lingually to a marked degree
• Distal aspect :-• Crown is narrower distally than mesially• tapers markdly towars distal end• Disto buccal cusp is long and sharp• Disto ingual cusp is poorly developed• Cervical line may curve occlusally• All three roots are seen• Point of bifurcation of disto buccal root and lingual root is near CEJ
• Occlusal aspect: -• The Calibration of distance between mesiobuccal line angle and disto buccal ling angle is greater than mesio lingual and distolingual• the occlusal surface has a central fossa, mesial triangular fossa just inside mesial marginal ridge.• Buccal developmental groove divides mesiobuccal and disto buccal cusp occlusaly• Oblique ridge is found connecting the mesio lingual and disto buccal cusp• Distal marginal ridge is then and Poorly difined.
Maxillary second Molar• Buccal aspect: -• Resemble permanent maxillary first molar but is smaller• two well defined buccal cusp and buccal groove is seen• Crown is longer than the first moler• Crown is narrow at cervix• Roots appears slender from this aspect• the point of bifurcation between the buccal root is close to cervical line of crown
• Lingual aspect: -• Crown shows theree cusps : – Mesio lingual – Disto Lingual – Supple mental• Supplemental cusp is also known as tubercle of carabelli• A well defined developmental groove seprates the mesio lingual cusp from disto lingual cusp• All the three roots are visible, lingual root is largest and thickset.
• Mesial aspects: -• Crown appears short because of its width buccolingually in comparision with its length• Mesio lingual cusp with its supplementay 5th cusp appears large in comparison with mesio buccal cusp• Mesio buccal root from this aspect is broad and flat• Lingual root has somewhat same curvature as the lingual root of maxillary first molar.
• Distal aspect: -• Distal calibration of crown is less than mesial• Disto buccal and disto lingual cusps are about same in length• the cervical line is approximately straight• All three roots are seen.• Disto buccal root is shorter and narrower than others• The point of bifurcation between distobuccal root and lingual root is more apical in location than any of other point of bifurcation.
• Occlusal aspect: -• Rhomboidal in shape• well developed cusp and a supplemental cusp is found• Buccal surface is flat• The occlusal surface consist of7. Central Fossa8. Mesial triangular fossa9. Central groove10.Oblique ridge11.Distal developmental Groove12.Distal triangular fossa13.Lingual developmental groove14.Distal marginal ridge15.Mesial Marginal Ridge16.Central pit17.Mesial marginal ridge18.Central pit
Mandibular First Molar• Buccal aspect: -• Mesial outline of crown is straight constricting the crown at cervix• Distal portion of crown is shorter than the mesial portion• Two buccal cusps are distinct• No developmental groove• mesial cusp is larger than distal• Roots are long and slender• They spread greatly at apical third beyond the outline of crown
• Lingual aspect: -• Crown, root converge lingually to marked degree• Disto lingual cusp is rounded• Mesio lingual cusp is long and sharp• Mesial marginal ridge is well developed• Cervical line is straight
• Mesial aspect: -• The most noticeable thing from mesial aspect is extreme curvature buccaly at cervical third• Both the mesio buccal and mesio lingual cusps are seen with a well developed marginal ridge• Cervical line slants upwards bucco-lingually• Root end is flat and square• Development depression is present• Buccal and lingual outline of root drop straight down to crown
• Distal aspect: -• Cervical line doesnt drop buccally• Length of crown buccally and lingually more uniform.• Distobuccal and distolingual cusps are not as sharp as mesial• Distal marginal ridge is not well defined• Distal root is rounded and shorter
• Occlusal aspect: -• Rhomboidal in shape• Mesiolingual cusp may be seen as largest and well developed• Buccal and central developmental grooves are found• Other Landmarks are:• Central developmental groove• Lingual developmental groove• Distal marginal ridge• Distal triangular fossa
Mandibular second molar• Buccal aspect: -• narrow mesio distal calibration at the cervical portion of crown when compared with celebration mesiodistally on crown at contact level• Mesio buccal and disto buccal developmental grooves divide the surface in there cusp (tow buccal and a distal)• Roots are slender and long• Have characteristics flare mesially• Point of bifurcation is found immediately below cej.
• Lingual aspect: -• Two lingual cusps of almost equal dimension are seen• A short lingual groove is present• Cervical line is straight• Mesial portion of crown seems to be little higher• A portion of each of there buccal cusp may be seen.
• Mesial aspect: -• Crest of contours buccally is more prominent• Marginal ridge is high• Lingual cusp is longer and higher• the mesial root is broad and flat with a blunt apex
• Distal aspect: -• Crown is not as wide as mesially• Disto lingual cusp is well developed• Cervical line is regular• Distal root is almost as mesial and flattened on distal surface• Distal root taper more at apical
• Occlusal aspect: -• Three buccal and two lingual cusps are equally matched• Well defined triangular ridge found.• Other landmarks are central groove , lingual groove, Mesial and distal groove.
REFERENCES• .• .wheeler s dental anatomy, physio logy and occlusion: ash, nelson• . text book of dental anatomy: satish chandra• . text book of pedodontics : damle• text book of pedodontics : s . tondon