Dental Anatomy, Physiology and Occlusion PDF 2024-2025

Dental Anatomy, Physiology and Occlusion Prof. Elham Fathy Department of Oral Biology Faculty of Dentistry Suez Canal University 2024 - 2025 Human dentition course - Introduction and nomenclature - Tooth anatomy and surfaces -...

Dental Anatomy, Physiology and Occlusion Prof. Elham Fathy Department of Oral Biology Faculty of Dentistry Suez Canal University 2024 - 2025 Human dentition course - Introduction and nomenclature - Tooth anatomy and surfaces - Function of teeth - Tooth surfaces and division into thirds - Anatomical land marks of the crown - Life cycle of teeth - Surface anatomy of the permanent teeth; Maxillary central and lateral incisors Mandibular central and lateral incisor Maxillary and mandibular canine Maxillary premolars Mandibular premolars Maxillary molars Mandibular molars - Deciduous dentition - Teeth at different ages - Mandible at different age - Significance of crown outline - Physiologic tooth form protecting the periodontium, Arrangement of teeth and occlusion  Introduction and nomenclature Introduction. Types & forms of teeth. Types of dentitions. Numbering & coding systems of teeth. Macro- & micro-anatomy of teeth. Functions of teeth. Surfaces of teeth. Division of tooth surfaces into thirds. Line & point angles.  Introduction What is Anatomy? It is the branch of biology concerned with the study of the structure of organisms and their parts. What is Dental Anatomy? It is a field of anatomy that studies human tooth form & structure ( morphology). The development, classification of teeth and their function as they contact one another in dental occlusion. What is dental arch? It is that part of the oral cavity where teeth are arranged. Dental arches  To simplify the study of teeth positions, a cross is drawn: The horizontal line separates upper from lower dental arches. The vertical line---midline or central line. Equally divides the face & arches into Rt & Lt segments. Each of these segments is called quadrant.  Types & forms of teeth Anterior teeth 1. Incisors 2. Canines (Cuspids) -4 in each dental arch. -2 in each dental arch. -2 in each quadrant. -1 in each quadrant. -Central incisor: 1st tooth to ml. -3rd tooth to ml. -Lateral incisor: 2nd tooth to ml. -For food cutting & tearing. -For cutting & incising of food.  Posterior teeth 3.Premolars 4. Molars (Bicuspids) -6 in each dental arch. -4 in each dental arch. -3 in each quadrant. -2 in each quadrants. -1st molar: 6th tooth. -1st premolar: 4th tooth. -2nd molar: 7th tooth. -2nd premolar: 5th tooth. -3rd molar: 8th tooth. -for tearing & grinding of -wide surface & multiple food. cusps. -for food grinding.  Types of dentitions: 1. Deciduous 2. Mixed 3.Permanent dentition. dentition. dentition. 6m-6y 6y-12y 12y-whole life  Types of dentitions: 1. Deciduous dentition. 6m-6y 20 in oral cavity. Primary temporary milk teeth. 10 in each dental arch. Predecessors. 5 in each quadrant. Their eruption: Their “dental formula” expresses their number in only one side of the mouth: Starts at 6m for lower central incisor. I 2/2 incisors 2 upper & 2 lower. Ends at 2y for upper second molar. C 1/1 canines 1 upper & 1 lower. M 2/2 molars 2 upper & 2 lower. Dental Formula of deciduous teeth Dental formula is a shorthand system which indicates the dentition of only one side of the mouth, ( both upper and lower quadrants). The dental formula for human deciduous dentition is as following :  2 1 2  I ---- C ---- M ----  2 1 2 I - Incisor, C - Canine, M - Molar 2 Incisors (Central & Lateral) 1 Canine 2 Molars 1st molar & 2nd molar  Transitional phase. Both deciduous & permanent are present. 2. Mixed Begins at 6y dentition. eruption of 1st perm. 6y-12y Molar. Ends when all deciduous teeth shed & replaced with permanent teeth around 12y. 3. Permanent dentition. (12y-whole life) 32 teeth in oral cavity. 16 in each dental arch. 8 in each quadrant. Called: successors bec. They replace their deciduous predecessors except permanent molars they have no deciduous predecessors. “Dental formula”: I 2/2. C 1/1. P 2/2. M 3/3.  Dental Formula of permanent teeth The dental formula for human permanent dentition is as following : 2 1 2 3 I ---- C ---- P ----- M ---- 2 1 2 3 I - Incisors, C - Canine, P - Premolars, M - Molars 2 Incisors (Central & Lateral) 1 Canine 2 Premolars (1st & 2nd premolar) 3 Molars (1st, 2nd & 3rd molar)  Succidaneous Teeth:  Non succidaneous Teeth:  Those permanent tooth, which  Those permanent tooth, replace a deciduous tooth. which do not replace a  Example : deciduous tooth and  Permanent teeth like come directly in place.  Example :  Incisors, Canines and Premolars.  Permanent molars SuccidaneousTeeth NonsuccidaneousTeeth SuccidaneousTeeth NonsuccidaneousTeeth The Dentition SUMMERY Humans have two dentitions 1-The primary dentition: (deciduous ) 20 teeth. 10 maxillary and 10 mandibular. 5 teeth are present in each quadrant. 2 incisors, 1 canine and 2 molars. The dental formula is: 2 1 2 I --- C ---- M ---- = 10 2 1 2 2-The permanent dentition: (secondary, adult or succedaneous ) 32 teeth, 16 maxillary and 16 mandibular, 8 teeth in each quadrant are present, 2 incisors, 1 canine, 2 premolars and 3 molars. The dental formula is : 2 1 2 3 I ---- C ---- PM --- M ---- = 16 2 1 2 3 The permanent molars are not preceeded with deciduous teeth so they may be termed as non-succedaneous teeth. 1- Deciduous or primary dentition period starts from 6 months till 6 years ( until the eruption of the first permanent tooth). 2- Mixed dentition period: from 6 years to 12 years where the deciduous teeth are replaced by permanent teeth. 3- Permanent dentition: By 12 years, Permanent teeth are only present in mouth.  Deciduous Mixed Primary dentition Mixed dentition 6m-6y Permanent 6 y -12 y Shedding: It is the physiological loss of the deciduous teeth and their subsequent replacement by permanent teeth. Permanent dentition 12 y and up  X – Ray Showing 1- Primary dentition 2- Mixed dentition 6m-6y 6 y - 12 y 3- Permanent dentition 12 y and up  Numbering & coding systems of teeth To identify specific tooth mention: Dentition arch quadrant teeth. Deciduous upper right e.g: incisor. Permanent lower left canine. Much easier to use these systems: (1) Palmer notation system: Deciduous Permanent set. set. 1) Palmer Notation System: It represents the four quadrants of the dentition as if you are facing the patient. Upper right Upper left Lower right Lower left ☻The permanent teeth are numbered from 1-8 on each side from the midline. Upper right Upper left 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 Lower right Lower left 8 8 7 7 6 54 3 2 1 1 3 45 6 8 2 7 8 6 5 4 3 4 567 2 1 1 2 3 The deciduous teeth are lettered from A-E on each side from the midline. Upper right Upper left E D C B A A B C D E E D C B A A B C D E Lower right Lower left D C B A E E D C B A Palmer Notation System 12 43 2- The Federation Dentaire international (FDI) (Two digit system) The teeth are designed by using binomial systems: a. The first number of the code is located at the left side and indicates the quadrant. In the permanent dentition. U.R. 1 2 U.L. L.R. 4 3 L.L. In the deciduous dentition. U.R 5 6 U.L. L.R. 8 7 L.L. b- The second number is located at the right side and indicates the number of the tooth in the quadrant according to Palmer’s. ☻The two numbers should be pronounced separately. a. Permanent teeth 18 17 16 15 14 13 12 11 21 22 23 24 25 26 27 28 48 47 46 45 44 43 42 41 31 32 33 34 35 36 37 38 b. Deciduous teeth 55 54 53 52 51 61 62 63 64 65 85 84 83 82 81 71 72 73 74 75 Deciduous dentition Permanent dentition  Numbering and coding systems of the teeth 3)The universal numbering system:. The number is always preceded by the sign # to designate that the system is used for universal system. Permanent teeth (1 – 32) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 Deciduous teeth (1 – 20) 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 ☻When we use numbers for deciduous teeth we have to put (d) beside the number e.g. # 5d OR Deciduous teeth (A - T) A B C D E F G H I J T S R Q P O N M L K 3) The universal numbering system  1D 2D 3D 4D 5D 6D 7D 8D 9D 10D 20D 19D 18D 17D 16D 15D 14D 13D 12D 11D  Functions of teeth 1- Mastication cutting the foods into small pieces, thus make easy to swallow. 2- Appearance & Aesthetics Nice smile Bad smile Contributes a lot in facial beauty 3- Speech Speech : Helps in speech, pronunciation of particular words (you can feel when an edentulous patient talks). THINK DENTAL !! THINK RELATED ANATOMY !!! THANK YOU !!