Ternopil State Medical University named by I Gorbachevskyj

Ternopil State Medical University named by I. Gorbachevskyj Topic. Historical stages of Therapeutic Dentistry, its chapters. The value of scientific research of Ukrainian scientists. Dental instruments. Histological and clinical anatomy of the teeth. Dental charting. Signs of teeth. Department of Therapeutic Dentistry Lecturer: Levkiv Mariana 1

Little about Dentistry, is the branch of medicine that is involved in the evaluation, diagnosis, prevention, and surgical or non-surgical treatment of diseases, disorders and conditions of the oral cavity, maxillofacial area and the adjacent associated structures and their impact on the human body. 2

• Dentistry has a long and fascinating history. From the earliest times, human beings have been plagued by dental disease. • Many of the remarkable techniques used in modern dentistry can be traced to the very earliest of times in every culture. 3

• • • • • Therapeutic Dentistry- is a part of dentistry that studies the reasons and mechanisms of teeth diseases, periodontium tissues diseases and oral mucosa diseases, theirs diagnosis, treatment methods and prevention. Therapeutic Dentistry includes such chapters: - Propaedeutic course; - Preventive dentistry and Endodontology; - Periodontology; - Oral Pathology- (deals with oral mucosa diseases). Propaedeutic course - deals with the history of dentistry, study the anatomical and physiological features of the oral cavity, dental instruments and dental office equipment, ergonomics issues, ethics and deontology, structure of Ukraine dental service. 4

Preventive dentistry & Endodontics • A branch of dentistry that deals with the prevention, diagnosis and treatment of the diseases affecting dental pulp, root and periapical tissues. • Restoring a tooth portion affected by dental caries, root canal treatment of the tooth whose dental pulp is infected etc. are some of the commonly performed treatment procedures in Endodontics. 5

Periodontics • Periodontology or Periodontics is the specialty of dentistry that studies supporting structures of teeth, diseases, and conditions that affect them. . 6

Oral Pathology Oral pathology is the specialty of dentistry and pathology which deals with the nature, identification, and management of diseases affecting the oral and maxillofacial regions. 7

BASIC INSTRUMENTS • There a few basic instruments that are universal to almost every procedure in dentistry. 8

Hand instruments Working end(s) of instruments • Are the functional parts of the instrument • Can have a variety of functions including: cutting, packing, carving, placing and condensing • Are adapted to the function of the particular instrument • May be bevelled (i. e. the working end is cut at an angle) • An instrument can be single-ended (one working end) or double-ended (two working ends) Shank of an instrument • The part between the working end and the handle • Can be straight or angled • The function of the instrument determines the angle and flexibility of the shank Handle of an instrument • Is the part of the instrument that the operator grasps • Design is related to the function of the instrument 9

Set of examination instruments Mouth mirror Functions • • To provide indirect vision • • To reflect light • • For retraction and protection of oral tissues • • For magnification (the number of the mirror represents size of mirror head) 10

Sickle/contra-angled probe Functions • • Detection of: • � defective pits and fissures; • � calculus; • � deficient margins of restorations, crowns and bridges; • � caries; • • Examination (pointed tip allows good tactile sensitivity) Varieties • • Can be single-ended or double-ended • • Many different styles available • • Working ends may vary (straight, curved) 11

Periodontal probe Function and features • Measure the depth of periodontal pockets • Tip is calibrated in millimetres • Blunt end reduces the possibility of tissue trauma Varieties • Single-ended or double-ended • Can be straight, curved or at right angles • Plastic types available 12

College tweezers Functions • • Placing small objects in the mouth and retrieving small objects from the mouth • • Locking type ‘lock’ to prevent dropping materials Varieties • • Locking and non-locking types • • Working ends can be straight, curved, serrated or smooth 13

INSTRUMENTS USED IN BASIC RESTORATIVE PROCEDURES Spoon excavators Functions and feature • • A spoon-shaped working end for ‘spooning’ out dentinal caries from the cavity preparation • • Edges of working end are sharp • Any remaining caries will be removed with the conventional handpiece and a round bur 14

Mixing spatulas Function and feature • • Used to mix dental materials • • Anodised aluminium spatula will not stick to any composite materials or discolour materials 15

Flat plastic instrument. Also called: plastic instrument Functions • • To deliver materials to the cavity preparation • • To remove excess materials Varieties • • Various sizes and shapes available • • Can be single-ended or double-ended 16

Round-ended plastic Functions and feature • • Used to create anatomical shapes in composite material during restorations • • The ball-ended plastic instrument can also be used to pack and condense composite materials 17

Rotary instruments HANDPIECES AND BURS • Dental handpieces and rotary attachments help to make dental treatment more comfortable for the patient and reduce the amount of time needed to complete procedures. 18

Air turbine handpiece Also called: fast handpiece, high speed handpiece, air rotor handpiece Type • Contra-angled Functions, precaution and features • • Removal of tooth tissue during restorations and preparation of teeth for fixed prosthetic appliances • • Polishing of restorations • • High speeds create heat and friction – handpiece must be run with water to cool the tooth to prevent pulpal damage • • High speed saves treatment time and reduces vibration 19

Driven by • Turbine – may need to be lubricated – check manufacturer’s instructions • Compressed air rotates the turbine, which then rotates the bur Speed Check manufacturer’s specifications (can run up to 500000 rpm) Grip Accepts friction grip attachments Attachment Dental unit Varieties • Different types of chucks available (e. g. those which need bur changing tool) • With or without light • Smaller heads for difficult access 20

Straight handpiece Functions • • Used in surgical procedures to remove bone (cannot use air turbine as the water is not sterile) • • Used extra-orally at chairside or in the dental laboratory (e. g. for denture adjustments) Speed • can run up to 40 000 rpm Grip • Accepts long shank attachments Attachment • Electric motor that fits into the base of the handpiece 21

Slow Speed Handpieces Type • Contra-angled Functions • • Removal of caries • • Polishing • • Procedures that require torque • • Refine cavity preparations and adjust occlusion Driven by • Gears Speed • The speed of the handpiece ranges from 0 to 40 000 rpm Attachment • Electric motor that fits into the base of the handpiece 22

Burs Head • This is the working end • Function depends on the size and shape of the head • Many different sizes and shapes, each used for a different function (cutting, polishing and finishing) Neck • The part that connects the head to the shank – usually narrows towards the head Shank • The part that fits into the handpiece • Shapes and lengths vary, depending on function • Can sometimes be marked to identify bur type (stripes or coloured bands) 23

Some points to remember about rotary attachments and burs • Most often called burs, but also available are wheels, discs, rubber points, rubber cups and stones • Each has a particular function (cutting, polishing, finishing or caries removal) • Are made from various materials (tungsten carbide, diamond and steel) • Can have flutes (the cutting edges) • The end of the shank determines which handpiece the attachment will fit into: q � Long straight shank – straight handpiece q � Latch grip – conventional type/slow speed handpiece q � Friction grip shank – air turbine handpiece/high speed handpiece q � Other various attachments such as snap or screw-type attachments 24

Shape and function • Shape determines function; the examples that follow relate to tungsten carbide burs: • • Rose head/round – cutting and removing caries • • Pear – to shape the cavity preparation • • Fissure – to shape and prepare the cavity preparation 25

Grip and corresponding handpiece Refers to the way the bur’s shank is ‘gripped’ into the handpiece • Composition • • Refers to the head of the bur and what it is made from • • Generally: • � Most latch grip burs are made of steel • � Most fiction grip burs are made of tungsten carbide or diamond • � Most long shank burs are made from steel if they are meant for surgical procedures and stainless steel if they are meant for laboratory purposes 26

Anatomical and histological features of teeth 1. In adult humans there are 32 permanent teeth. 2. These are preceded during childhood by 20 deciduous teeth. 3. The tooth lies in a bony socket, the alveolus, that is covered an oral mucosa called the gingiva (gums) Copyright © 2004 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED. 27

Tooth structure 28

Enamel • Physical characteristics of enamel • Enamel is highly mineralised and is the hardest tissue in the body. Enamel covers the anatomical crown of the tooth and varies in thickness; it is semi-translucent and its colour can vary from bluish white to hues of yellow. • Chemical composition of enamel • Enamel consists of 96– 97% inorganic material (by weight), the main inorganic component being hydroxyapatite, 1% organic material (by weight), the main organic component being protein and 2– 3% water (by weight). 29

• Structure of enamel • Enamel is made up of millions of enamel prisms or rods, which run from the amelo-dentinal junction to the enamel surface. Each prism is made up of a large number of enamel crystallites. 30

Dentine • Physical characteristics of dentine • Dentine is mineralised tissue forming the bulk of the tooth. It underlies the enamel in the crown area and is covered by the cementum in the root area. Dentine is pale yellow in colour and is harder than bone and cementum but not as hard as enamel. • Chemical composition of dentine • Dentine consists of 70% inorganic material (by weight) of which the main inorganic component is hydroxyapatite (Ca 10(PO 4)6(OH)2). Organic material constitutes 20% (by weight). The main organic component is collagen fibres embedded in amorphous ground substance. The remaining 10% (by weight) is water. 31

• • Structure of dentine Dentine consists of many dentinal tubules that run parallel to each other, following a double curved course, and extend from the pulp to the amelodentinal junction. Each dentinal tubule contains an odontoblast process surrounded by intercellular ground substance composed of fine collagenous fibrils. The odontoblast cells are a layer of closely arranged cells on the pulpal surface of the dentine with their nuclei situated at the basal (pulpal) end of each cell. 32

Cementum • • Physical characteristics of cementum Cementum is a pale yellow, calcified tissue covering the root dentine. It is softer than dentine and can easily be worn away, resulting in exposure of the dentine. Its thickness varies according to location; it is thickest towards the apical third of the root and thinnest cervically. Chemical composition of cementum Cementum is 65% by weight inorganic (mainly hydroxy-apatite), 23% organic (mainly collagen) and 12% water. 33

Dental pulp • Pulp is a soft vascular connective tissue occupying the centre of the tooth. The shape of the pulp approximately follows the shape of the outer surface of the tooth. The pulp is made up of a pulp chamber in the crown and root canals extending the length of the root. The shape and number of root canals can vary considerably. At the apex of each root is a foramen or foramina through which blood vessels, nerves and lymphatics pass. Small projections of the pulp are found under each cusp; these are known as pulp horns or cornua. 34

Dental pulp • The dental pulp is surrounded by dentine and is contained in a rigid compartment. • Functions of pulp • The dental pulp has the following functions: • ■ At late bell stage the cells at the periphery of the pulp differentiate into odontoblasts forming dentine. • ■ It provides nutrients to the odontoblasts. (trophic function ) • ■ It acts as a sensory organ especially when dentine is exposed. The pulp rapidly responds to stimuli such as caries and attrition by laying down reparative or reactionary dentine. (reparative function) • ■ It mobilises defence cells when bacteria enter it. (protective function) • ■ Cells proliferating in the pulpal tissue create pressure; this is thought to play a part in tooth eruption. 35

Periodontal ligament • • The periodontal ligament is a specialised fibrous connective tissue that surrounds the root area of the tooth. It consists mainly of collagenous fibres. It has the following functions: ■ It provides a support mechanism for the tooth; it cushions teeth against excessive occlusal forces, preventing damage to the blood vessels and nerves at the root apex. ■ It maintains the functional position of a tooth by keeping the teeth in contact and prevents the tooth from drifting or tilting. ■ The periodontal fibres undergo continuous change. Its cells form, maintain and repair the alveolar bone and cementum. ■ Sensors in the periodontal ligament provide proprioceptive input, detecting pressures on the tooth. ■ The periodontal ligament has a rich supply of blood, which provides nutrients to the cementoblasts. 36

• The periodontal ligament is made up of two groups of fibres: the gingival fibre groups and the principal fibre groups. The gingival fibre groups of the periodontal ligament include: • ■ Dentino-gingival fibres (free gingival fibres) are attached to the cementum and fan out into the gingival tissue. • ■ Trans-septal fibres run horizontally from the cervical area of one tooth to the adjacent tooth. • ■ Alveolo-gingival fibres arise from the alveolar crest and run coronally into the attached and free gingiva. • ■ Circumferential fibres (circular) encircle the neck of the tooth. 37

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The principal fibre groups of the periodontal ligament are: • ■ Oblique fibres which run obliquely from alveolar bone to tooth. • ■ Apical fibres which radiate from the apex of the tooth to the adjacent alveolar bone. • ■ Horizontal fibres which run horizontally from the cementum to the adjacent alveolar bone. • ■ Inter-radicular fibres which are found between the roots of multi-rooted teeth and run from the root to the adjacent alveolar bone. 39

TEETH STRUCTURE Primary teeth 40

TEETH STRUCTURE Permanent teeth 41

TOOTH FUNCTION Types Function 1. Incisor is a tooth that has one root; function: to cut and cut off food. 2. Canines are the teeth that have one root and has the function to rip the food. 3. Premolar teeth that had two/one roots; used to grind and chew food. 4. Molar tooth is a tooth that has two/three roots; have a function for crushing and chewing food.

Morphological differences between primary and permanent teeth • • • There are numerous differences between the primary and permanent dentition, many of which give rise to considerations in relation to operative treatment. Essentially, primary teeth have: ■ A shorter crown. ■ A lighter colour. ■ Narrower occlusal surfaces. ■ Thinner enamel and dentine. ■ Relatively larger pulps. ■ Curved roots (to accommodate the developing permanent successor). Copyright © 2004 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED. 43

Numbering Systems • Universal/National System – Developed in 1968 – Most commonly used in the United States • Fédération Dentaire Internationale System – Canada and European countries use this – Easily adapted by computer and is widely used in most countries • Palmer System 44

Universal numbering system A system is used in the United States, called the universal system. This is a two-digit system but the teeth are numbered from 1 through to 32 in a clockwise direction starting with the upper right third molar: Right 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Upper Lower 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 Left 45

ISO/FDI numbering system The mouth is divided into four quadrants and each quadrant is given a number, starting with the upper right quadrant and working in a clockwise direction. For example, the upper left quadrant is 2. The teeth are then allocated a number starting from the midline, so all central incisors are 1 and all third molars are 8. Therefore the lower right second premolar is 45. Right 18 17 16 15 14 13 12 11 21 22 23 24 25 26 27 28 Upper Lower 48 47 46 45 44 43 42 41 31 32 33 34 35 36 37 38 Left 46

Palmer Notation System In this system, the dentition is divided into quadrants and the teeth in each quadrant are numbered 1 to 8 starting at the midline. Each quadrant is separated by a vertical line for right and left and by a horizontal line for upper and lower. Thus |6 is the upper left first molar in the permanent dentition. Right 8 7 6 5 4 3 2 1 | 1 2 3 4 5 6 7 8 Upper Lower 8 7 6 5 4 3 2 1 | 1 2 3 4 5 6 7 8 Left 47

Universal/National Numbering and Lettering System 8 9 Maxillary right Maxillary left E F Maxillary right 1 32 Mandibular right Third molars 25 24 16 A 17 T Mandibular left Maxillary left J Second molars Mandibular right P O Primary teeth K Mandibular left Permanent teeth 48

Fédération Dentaire Internationale System for Numbering 1 Maxillary right quadrant “ 1” 1 Maxillary left quadrant “ 2” 1 1 Maxillary right quadrant “ 5” 8 Third molars 8 8 5 Maxillary left quadrant “ 6” 5 Second molars Mandibular right quadrant “ 8” Mandibular right quadrant “ 4” 1 1 Mandibular left quadrant “ 3” 1 1 5 Mandibular left quadrant “ 7” Primary teeth Permanent teeth 49

Palmer System for Numbering 1 1 Maxillary right quadrant Maxillary left quadrant Maxillary right quadrant A A Maxillary left quadrant 8 8 E E Mandibular right quadrant Mandibular left quadrant 1 Mandibular right quadrant A A Mandibular left quadrant Primary teeth 1 Permanent teeth 50