Dental Anatomy and Occlusion Maxillary arch and Mandibular arch Arch trait – characteristic that can tell you if tooth is maxillary or mandibular. Only maxillary molars have an oblique ridge Mid line divides mouth into 4 quadrants. Max right (1), Max left (2), Man left (3), man right (4) Primary teeth are replaced by permanent teeth. Set trait – a charc. Which differentiates between primary and its analogue permananet teeth. Diphyodont, producing two sets of teeth (human) Polyphyodont, producing many sets (shark) Homodont – only one type of tooth (alligator) Heterodont – different classes and types of teeth (human, dog) serving diff functions. Teeth are ivided into 4 classes. Incisor, canine, premolar, molar. Class trait – trait to charc. Tooth into its class Incisor have incisal edge for cutting. Canine posses single cusp for piercing and tearing Molar is for grinding. Medial part of max incisor is longer than the distal side. Canine (cuspid) has longest root, in corner of mouth, since tearing, it is embedded in bone for stability, last tooth to fall out due to neglect. Premolars are distal to the canine. Occupy 4th and 5th positions. Sometimes premolars don’t develop. First premolar has double root, second has single root. Distal to the premolars are the molars. 1st 2nd and 3rd. first is the 6 year molar, 2nd is the 12 year molar, 3rd is wisdom tooth comes in between age 17-21. first premolar has large occlusal surface. The dental formula. For the human formula. Maxillary/mandibular For human species: I 2/2 C 1/1 PM 2/2 M 3/3 = 16*2 = 32 Type trait – differences between arch components of each class which render them easily identifiable. Canine has no type trait because it is the only of its type. Man central incisor is a little small and straighter than man lateral incisor. Anterior – incisor & canine. Posterior – premolars and molars Primary dentition is aka deciduous (lose their leaves) dentition and baby teeth. Do exfoliation. Permanent teeth that replace primary teeth are also called succedaneous teeth. No premolar primary teeth. All primary teeth come in by age 2. I 2/2 C 1/1 PM 0/0 M 2/2 The permanent molars are non-succedanous.

Permanent dentition period, period when only permanent teeth are present and which begins at approx 12 years and cont for rest of life. 6 months is when eruption of deciduous mandibular central incisor. (first tooth) Succadaneous teeth won’t erupt to replace until at least half of the root has formed. Standard order. Set, Arch, Quadrant, Type, Class. Example: Permanent Mandibular Right 1st Molar Numbering systems: Universal, FDI Notation, Palmer System (used by orthodontists). WE USE UNIVERSAL SYSTEM Universal: teeth are numbered 1-32. Starting with maxillary right 3rd molar, ending with mandibular right 3rd molar. Primary teeth are lettered A-T. FDI Notation uses quadrant numbers. Permanent quad 1-4 then the tooth, starting medial moving distal tooth is 1-8. Primary uses quad 5-8. Palmer is lines to indicate quadrant and tooth number. Primary teeth uses lines and letters instead of numbers. See notes sheet in folder for details (my notes on paper). A tooth consists of a crown and a root. CEJ (cementum enamel junction) (cervical line) is line that separates crown and root. Crown is functional for chewing covered in enamel. Root, anchors, embedded in bone and soft tissue. Socket it sits in is alveolus. Bone it is in is called Alveolar process. Under alveolar process of mandible is the body. Ramus is bone that connects jaw to skull. What you see in patient’s mouth is clinical crown. Clinical root (cant see) is embedded in bone. In lab you can see the anatomical crown and anatomical root. Cementum covers root, enamel covers crown. CEJ is wavier on anterior teeth. Cementum attaches root to alveolar. Periodontal ligaments attached to alveolar bone are embedded into the cementum. Under enamel is the dentin, under dentin is the pulp horns, pulp chamber and pulp canals. Gingival line is where crown meets the gum. Clinical crown is longer than anatomical crown when receded gums. Clinical crown is whatever you see in the mouth. ((Loops: Get magnification of 2.5 or 2.6, flip up design (preferably).)) Lecture 2:

Mesial vs. distal Facial…buchal.. and other Linguil – the inner arch (form inside the mouth) or palatel for maxillary. Proximal surface – any surface that touches another tooth (ex. Distal proximal is far from midline) Incisol = edge of incisor Occlusal surfaces – surfaces that come together when mouth closes. Gingivol – by gums 3 hard tissues (3 tissues of tooth) and 1 soft: Enamel- very hard… it is mineralized, working surface of tooth, protective outer area. Dentin – less hard, but still harder than bone, bulk of tooth Sementim – 50% calcified (hard, but less hard than dentin), covers root, anchors tooth Pupl- soft tissue that produces the dentin during whole life of tooth. Enamel Covers anatomical crown of tooth Hardest tissue in body, most densely mineralized… but can ware with acids, composed of rods… see slide… very brittle, needs dentin underneath to provide cushioning… cant have uned enamel… or will chip away. Acid (soda) will destroy dentin. Operative techniques use acid to etch enamel, makes it like Velcro so can add to it. Cementoenamel junction, CL (cervical line) Dentoenamel junction… Dentin Softer than enamel, gives tooth the form and elastic strength, forms throughout life, 70% inorganic, 30 organic (softer) composed of tube like structures called dentinal tubules. Primary – originally laid down (it’s near DEJ), secondary – laid down in life, tertiary – a response to a problem that is formed. Periodontal ligament –fibers that hold tooth in place.. tooth isn’t fused strait to bone.. or shouldn’t be. Cementum, more like bone (less hard than other 2), covers anatomical root. Absorbs blood? Formed continually in life. Cellular vs. acellular, The pulp – composed of odontoblast…slide, in pulp chamber.. become root canal. Root- bifurcated, trifurcated (2 3 roots) Root trunk – before root splits into terminal roots (which tell you if it bifurcated). ROOT: Apical – top. Middle and Cervial (bottom)/ occlusal on other teeth CROWN: top to bottom – cervical, middle, incisal Looking at mesial surface: lingual middle and labial - some changes.. buchal… check diagram in atlas.

Line angle- where 2 surfaces of a tooth meet. Ex- distal facial line angle. 8 line angles on a posterior – draw crown in cube. Line angle diagram in wheeler text – looks like a tooth coming out of a box. Point angle – intersection of 3 surfaces, 4 of them Cusps: projections on the crown of a tooth, major divisions of a tooth. 5 on molar. 1 on a canince, 0 on incisor. 2 or 3 on premolar. Cingulum – large rounded area…… get difinision Ridge – liniear elevation on tooth (hot dog shape in wax) Triangular ridge- prominent elevation from tip of cusp to centrlal area of occlusial surface Transverse ridge- 2 triangular ridges. A special type is the oblique ridge – crosses the tooth obliquely. Every cusp has 4 ridges, FDML Mamelons – small rounded projections of enamel on the incisal edge of newly erupted teeth. Sulcus – v shaped space between cusps (not a real grove). Depressions: Fossas: 1. cetral – occlusal center of posterior tooth – triangular depression. 2. triangular – found on occlusioal surface of posterior tooth, within confines or marginal ridges. 3. lingual – spoon shape to the back on an incisor. Within 4 ridges. Grooves – linear depression 1. developmental groove – 2. supplemental groove 3. central Pit- intersection of 2 or more groves Fissure – problem – where enamel doesn’t fuse together (lack of coelesence).. its like a big strait crack in tooth.. we seal it. Lobes area- where one tooth touches its neighbor – on the crest of curvature Height of contour – what sticks out in relation to how the tooth is standing in mouth.. different for everyone. Embrasure – spaces between teeth, occlusal, lingual, and cervical (which is beneath teeth -there is usually gingiva there.. but with recession, there can be a space showing). Crest of curvature- where surface curves Height of contour – part of tooth that comes out the most. Non succadaneus- molar

Succidaneus teeth – permanent except molar. Cusp ridge- each cusp has 4 ridges Triangular ridge – any ridge towards the center of the tooth. Incisor General information: 2 per quadrant Central incisor adjacent to midline First succedaneous teeth to erupt Functions: mastication, phonetics (th, f, and v sounds), esthetics ( the profile of lips) Maxillary central incisors – viewed labially of lingually- widest of the incisor class (arch trait) Maxillary central is larger than the ma…. Developmental Data Initiation calcification – 3-4 months Completion of enamel – 4-5 years Eruption – 7-8 years Completion of root – 10 years Charactersits Roots: 1 # lobes: 4 Pulp horns: 3 No cusps… only incisol edge Orientation in arch – mesial mesial.. Faciolingual angulation – 28’ (lateral is 26.. and angles keep getting smaller) Shape: Wedge shape from the proximal (comes to a point) See slide show………… Incisal ridge turns into incisal edge due to wear. PUT WAX LECTURE HERE Missed 25 min of notes… get from seth Crest of curvatures: • anterior tooth – correct contour is needed… so food glides… over contour and under is bad. Maxillary anteriors - .5 from lingual line.. learn curvature chart.. .and exceptions! Amount of CEJ curvature – medial of central incisor is greatest curvature.

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Greater on mesial slide… see slides.

Occlusal tabe: 50% of overall buccolingual width of the tooth… more… Marginal ridge height Continuity of central grooves Self cleansing qualities of teeth 1. smoothness of the enamel 2. overall shape of the teeth Ridges in the cervical area of teeth – Perikymata, and the depressions are imbricate (check spelling). Remnants of mammelons – looks like little chips in the tooth (incisors only?) Missed lecture. Canine EYE teeth Important to appearance 3rd from midline Calcification begins- 4 months Enamel completed (still inside) – 7 yrs Eruption – 13 years Root completed – 13 yrs Longest teeth in their arches. Wider LL than MD. Tearing, piercing, aesthetics 1 root, 1 pulp honr, 1 cusp, from 4 lobes. Corner stone of mouth Facial: pentagonal Proximal: triangular Don’t have to know numbers… but know which tooth is wider or longer where… and compared to others.. Distal is higher than medial (this is the bridge between anterior and posterior teeth. Posterior s are higher.. in the middle). Labial ridge = well developed middle lobe… very strong to tear… Imbrication lines – small circular lines…

From lingual: similar to labial, bulky/smooth cingulum, prominent marginal ridges, lingual ridge  ML and DL fossae. From mesial: triangular shape with point facing down, convex in all directions, LL is wider than central and lateral. Distal: shorter, cej less curved than mesial, is more circular (b/c connector tooth), Apical foramen – opening in apex (root) of tooth Mandibular canine: Similar functions, some difs. Less prominent lingual features, Mesial to CEJ is almost a strait line Learn for QUIZ!!!!!!!!!!! IJ JM JM II II IM MM MM MI MD Lingual is smoother, less pronounced ridge Mesial: in Incisal 3rd, narrowed LL than max canine, cingulum less prominent, Variation – bifurcation into 2 roots! Facial lingual (not seen in maxillary) will be on test!!!