This document provides an overview of dentin, including its physical, chemical, and structural properties. It discusses the types of dentin such as primary, secondary, and tertiary dentin. It describes the development of dentin through odontoblast differentiation and matrix formation followed by mineralization. Key structures of dentin like dentinal tubules, peritubular dentin, and predentin are defined. Theories of pain transmission through dentin and age-related functional changes in dentin are also summarized.
Dentine is the tissue that makes up the bulk of the tooth beneath enamel. It has both inorganic and organic components. The inorganic portion is made up of hydroxyapatite crystals that are smaller and more carbonate-rich than enamel. Collagen fibrils make up the organic matrix. Dentine also contains non-collagenous proteins and lipids that play roles in mineralization. Dentinal tubules radiate outward from the pulp cavity and contain odontoblastic processes, nerves, and dentinal fluid. With age and in response to stimuli, peritubular dentine deposits form, narrowing the tubules. Secondary and tertiary dentines are laid down over time. Regional variations in
The document discusses the formation and types of dentin. It begins by explaining that dentinogenesis is initiated by odontoblasts and forms the bulk of each tooth crown and root. There are several types of dentin that form at different stages: mantle dentin forms first along the enamel layer, primary dentin makes up most of the tooth, and secondary and tertiary dentins are deposited throughout life. Tertiary dentin specifically forms in response to stimuli like decay. Dentin contains tubules that house odontoblast processes and provide sensitivity; it is made up of both organic and inorganic components including collagen and hydroxyapatite.
Here are some suggested du'as before and after studying, and during exams:
Before studying:
اللهم أعني على ذكرك وشكرك وحسن عبادتك
O Allah, help me remember You, be grateful to You and worship You in the best way.
اللهم بارك لي في علمي وزدني من فضلك وانفعني بما علمت
O Allah, bless me in my knowledge, increase me in Your bounty and benefit me with what I
This document provides an overview of dentin, including:
- Its history, development, physical and chemical properties, structure, types, and innervation
- Dentinogenesis is the process by which dentin is formed through the secretion and mineralization of an organic matrix by odontoblasts.
- Dentin's main components are hydroxyapatite crystals, collagen fibers, non-collagenous proteins, and water. Its tubular structure and composition provide mechanical strength and sensitivity.
- Different types of dentin include primary, secondary, and tertiary dentin, which vary in their location, thickness, mineralization, and quality.
This document provides an overview of dentin, including:
- A brief history of discoveries related to dentin structure.
- Dentinogenesis, the process of dentin formation carried out by odontoblasts. Primary dentin formation beneath the enamel and root dentin formation are described.
- The physical properties, chemical composition, and structural components of dentin including dentinal tubules, predentin, peritubular and intertubular dentin.
- Features such as von Ebner's lines, lines of Schreger, and contour lines of Owen which represent incremental growth patterns in dentin.
Dentinogenesis is the formation of dentin by odontoblast cells that differentiate from dental papilla cells. Odontoblasts first form an uncalcified predentin matrix that then undergoes mineralization. There are two types of primary dentin formed - mantle dentin near the enamel and circumpulpal dentin forming the bulk of the tooth. Dentin has a microscopic structure consisting of dentinal tubules containing odontoblast processes, surrounded by highly mineralized peritubular dentin and less mineralized intertubular dentin.
The document provides an overview of dentin, including its composition, structure, types, properties and historical discoveries. Some key points summarized:
1. Dentin makes up the bulk of teeth and is composed of 65-70% organic material including collagen, and 20-25% inorganic material including calcium phosphate. It contains dentinal tubules that branch throughout.
2. There are three types of dentin - primary, secondary, and tertiary. Primary dentin forms most of the tooth, secondary develops after root formation, and tertiary is produced in response to damage or irritation.
3. Dentin has physical properties including a thickness of 3-10mm, hardness of 68KHN, and permeability
Enamel is the hardest tissue in the body and is composed primarily of hydroxyapatite crystals. It is formed through the process of amelogenesis by ameloblasts, which transition between secretory and maturation stages as they lay down the enamel matrix and facilitate mineralization. The unique structure of enamel, including enamel rods and interrod enamel, provides hardness but requires the underlying dentin to compensate for enamel's brittleness. The complex life cycle of ameloblasts and specialized enamel proteins are required for this intricate mineralization process and formation of enamel's highly mineralized structure.
Dentine is the tissue that makes up the bulk of the tooth beneath enamel. It has both inorganic and organic components. The inorganic portion is made up of hydroxyapatite crystals that are smaller and more carbonate-rich than enamel. Collagen fibrils make up the organic matrix. Dentine also contains non-collagenous proteins and lipids that play roles in mineralization. Dentinal tubules radiate outward from the pulp cavity and contain odontoblastic processes, nerves, and dentinal fluid. With age and in response to stimuli, peritubular dentine deposits form, narrowing the tubules. Secondary and tertiary dentines are laid down over time. Regional variations in
The document discusses the formation and types of dentin. It begins by explaining that dentinogenesis is initiated by odontoblasts and forms the bulk of each tooth crown and root. There are several types of dentin that form at different stages: mantle dentin forms first along the enamel layer, primary dentin makes up most of the tooth, and secondary and tertiary dentins are deposited throughout life. Tertiary dentin specifically forms in response to stimuli like decay. Dentin contains tubules that house odontoblast processes and provide sensitivity; it is made up of both organic and inorganic components including collagen and hydroxyapatite.
Here are some suggested du'as before and after studying, and during exams:
Before studying:
اللهم أعني على ذكرك وشكرك وحسن عبادتك
O Allah, help me remember You, be grateful to You and worship You in the best way.
اللهم بارك لي في علمي وزدني من فضلك وانفعني بما علمت
O Allah, bless me in my knowledge, increase me in Your bounty and benefit me with what I
This document provides an overview of dentin, including:
- Its history, development, physical and chemical properties, structure, types, and innervation
- Dentinogenesis is the process by which dentin is formed through the secretion and mineralization of an organic matrix by odontoblasts.
- Dentin's main components are hydroxyapatite crystals, collagen fibers, non-collagenous proteins, and water. Its tubular structure and composition provide mechanical strength and sensitivity.
- Different types of dentin include primary, secondary, and tertiary dentin, which vary in their location, thickness, mineralization, and quality.
This document provides an overview of dentin, including:
- A brief history of discoveries related to dentin structure.
- Dentinogenesis, the process of dentin formation carried out by odontoblasts. Primary dentin formation beneath the enamel and root dentin formation are described.
- The physical properties, chemical composition, and structural components of dentin including dentinal tubules, predentin, peritubular and intertubular dentin.
- Features such as von Ebner's lines, lines of Schreger, and contour lines of Owen which represent incremental growth patterns in dentin.
Dentinogenesis is the formation of dentin by odontoblast cells that differentiate from dental papilla cells. Odontoblasts first form an uncalcified predentin matrix that then undergoes mineralization. There are two types of primary dentin formed - mantle dentin near the enamel and circumpulpal dentin forming the bulk of the tooth. Dentin has a microscopic structure consisting of dentinal tubules containing odontoblast processes, surrounded by highly mineralized peritubular dentin and less mineralized intertubular dentin.
The document provides an overview of dentin, including its composition, structure, types, properties and historical discoveries. Some key points summarized:
1. Dentin makes up the bulk of teeth and is composed of 65-70% organic material including collagen, and 20-25% inorganic material including calcium phosphate. It contains dentinal tubules that branch throughout.
2. There are three types of dentin - primary, secondary, and tertiary. Primary dentin forms most of the tooth, secondary develops after root formation, and tertiary is produced in response to damage or irritation.
3. Dentin has physical properties including a thickness of 3-10mm, hardness of 68KHN, and permeability
Enamel is the hardest tissue in the body and is composed primarily of hydroxyapatite crystals. It is formed through the process of amelogenesis by ameloblasts, which transition between secretory and maturation stages as they lay down the enamel matrix and facilitate mineralization. The unique structure of enamel, including enamel rods and interrod enamel, provides hardness but requires the underlying dentin to compensate for enamel's brittleness. The complex life cycle of ameloblasts and specialized enamel proteins are required for this intricate mineralization process and formation of enamel's highly mineralized structure.
The document summarizes the stages of odontogenesis, or tooth development, from the dental lamina stage through root formation. It describes how during embryonic development, the dental lamina thickens to form tooth buds, which develop through bud, cap, and bell stages. During these stages, the enamel organ and dental papilla form. Odontoblasts then deposit dentin while ameloblasts deposit enamel. After crown formation, the root develops through the formation of the epithelial root sheath. Cementum is later deposited on the root surface by cementoblasts.
An odontoblast is a biological cell of neural crest origin whose main function is formation of dentin.
This slide gives a detailed explanation of the same.
Dentin is a hard yellowish substance that forms the bulk of teeth. It is composed of 70% hydroxyapatite crystals and 30% organic materials like collagen. Dentin is formed by odontoblasts cells differentiated from dental papilla cells. It determines the shape of teeth and contains microscopic tubules that house the processes of odontoblast cells. Dentin is harder than bone but softer than enamel. It has different layers with varying properties located at different regions of the tooth.
This document provides an overview of dentin, including:
- Its composition, formation process, and physical properties.
- The roles of odontoblasts and other components in dentinogenesis.
- The different types and structures of dentin, such as peritubular and intertubular dentin.
- Features like dentinal tubules, Von Ebner's lines, and the dentinoenamel junction.
- Its clinical significance, including use of the cementodentinal junction as a reference point in root canals.
- Potential developmental irregularities below the enamel-dentin junction that could predispose to caries.
The presentation discusses about tooth enamel in detail including its formation, characteristics, structure and histological features along with its clinical considerations. It is well supported with diagrams for better understanding of the text.
Suggestions and feedback will be well appreciated.
The document discusses the properties and development of dentin. It begins by introducing dentin and its role in tooth structure. Then it covers the physical and chemical properties of dentin, including its composition, hardness, thickness and density. The stages of dentin development and mineralization are described. Histologically, the key features of dentin are dentinal tubules, peritubular dentin, intertubular dentin and predentin. Structural lines like the dentinoenamel junction and Tome's granular layer are also outlined. Finally, the document notes different types of dentin like mantle dentin.
The document summarizes the development and growth of teeth from early formation in the embryo through the bell stage. It describes how the primary epithelial band forms and divides into the dental lamina and vestibular lamina. The dental lamina then goes through the bud, cap, and bell stages as it develops into the tooth germ and interacts with the underlying dental papilla and dental sac tissues to form the tooth structures. Key cellular and molecular signals that control tooth positioning and patterning are also discussed.
The dental pulp is the soft connective tissue inside teeth that gives them life. It develops from the dental papilla and occupies the central portion of teeth. The pulp contains blood vessels, nerves, fibroblasts, and odontoblasts - cells that produce dentin. With age, the pulp decreases in size and vascularity. It serves formative, protective, sensory, nutritive, and inductive functions. Precautions must be taken during cavity cutting to avoid damaging the pulp. Pulpitis is inflammation of the pulp, and root canal treatment removes inflamed or infected pulp tissue from teeth.
Dentin is the mineralized hard tissue that forms the bulk of the tooth beneath enamel and cementum. It is sensitive and continues to form throughout life at the expense of the pulp. Dentinogenesis begins when the dental papilla differentiates into odontoblasts. There are three stages of odontoblast development: differentiation, secretory formation of predentin and dentin, and a resting stage. Dentin is composed of hydroxyapatite crystals embedded in a collagen matrix. It has tubules that house odontoblast processes and dentinal fluid. The structure and composition of dentin provides strength and protection for the pulp.
Development Of Dentition & Occlusionjinishnath
The document discusses the development of dentition and occlusion from pre-natal development through post-natal development in humans. It covers:
- Pre-natal development of teeth including formation of the dental lamina and enamel organs.
- Stages of tooth development including bud, cap, and bell stages.
- Formation of the root and root sheath.
- Theories of tooth eruption.
- Post-natal development from birth through completion of primary dentition and the transitional periods involving eruption of permanent teeth.
The dental pulp is loose connective tissue located in the center of the tooth that contains blood vessels, nerves, and cells like odontoblasts. It has formative, nutritive, protective, and defensive functions. Over time, the pulp undergoes changes like decreased size and vascularity, increased calcification in the form of pulp stones or diffuse deposits, and reduced vitality.
Cementum is the mineralized tissue covering dental roots. It begins at the cementoenamel junction and continues to the root apex. Cementum provides attachment for collagen fibers (Sharpey's fibers) that bind the tooth to surrounding structures. Cementum develops in two stages: the prefunctional stage involving matrix formation and mineralization, and the functional stage where cementum deposition continues throughout life in response to tooth movement and wear. Cementum comes in various forms classified by development, cellularity, and fiber origin and includes acellular, cellular, intrinsic and extrinsic fiber cementum.
The document discusses the structure and composition of dental hard tissues, focusing on enamel. It describes enamel as the outermost rigid tissue that covers the tooth crown. Enamel is composed primarily of hydroxyapatite crystals arranged in rods that run from the dentin-enamel junction toward the outer surface. The rods are arranged to provide strength and withstand forces during chewing. Enamel hardness allows it to function in mastication but renders it brittle, requiring the underlying dentin as support.
The document summarizes the process of dentinogenesis or dentin formation. It involves differentiation of odontoblasts from dental papilla cells, secretion of an organic matrix, and mineralization of the matrix. Odontoblasts secrete collagen fibers and matrix vesicles that initiate mineralization. Dentin is formed in mantle dentin near enamel and circumpulpal dentin further inside via continuous mineralization. Root dentin formation begins after crown completion, guided by Hertwig's epithelial root sheath.
Tooth eruption involves three phases: pre-eruptive, eruptive, and post-eruptive. In the pre-eruptive phase, tooth germs develop and move within the jaw as it grows. The eruptive phase begins with root formation and ends when teeth reach the occlusal plane. Teeth emerge through the gums via bone resorption. In the post-eruptive phase, teeth continue moving axially and mesially to accommodate jaw growth and wear. Several theories attempt to explain eruption mechanisms, including root formation, bone remodeling, dental follicle activity, and periodontal ligament traction.
Dentin is the hard, bony tissue found in teeth beneath the enamel. It contains dentinal tubules that house odontoblastic processes and nerve fibers. Dentin is classified as primary, secondary, or tertiary depending on the time of its development. Primary dentin forms before and during eruption, secondary forms after root formation is complete, and tertiary dentin is produced in reaction to stimuli like attrition or caries. Tertiary dentin can be reactionary or reparative.
The document discusses the structure and development of the dental pulp. It begins by describing the pulp as a soft tissue composed of mesenchymal cells and specialized odontoblasts. The close relationship between odontoblasts and dentin results in the pulp-dentin complex. The primary role of the pulp is to produce dentin, but it also functions as a sensory organ. The document then proceeds to discuss pulp embryology and development, pulp anatomy and histology, innervation and sensitivity, aging changes, and other related topics.
Dentin is the mineralized tissue that forms most of the tooth. It is softer than enamel but harder than bone and cementum. Dentin consists of mineralized collagen and closely packed dentinal tubules that contain odontoblastic processes. Dentin is formed by odontoblasts, which deposit an organic matrix that then mineralizes. There are different types of dentin formed at various stages, including primary, secondary, and tertiary dentin formed in response to stimuli. The properties and microstructure of dentin can provide information in forensic dentistry applications.
This document provides information on dentin, including its composition, formation, and types. Some key points:
- Dentin makes up the bulk of the tooth and is composed of 65% inorganic material (mainly hydroxyapatite) and 35% organic material (collagen and proteoglycans).
- Odontoblasts are cells responsible for dentin formation. Their processes extend into dentinal tubules that permeate the dentin.
- Dentin formation begins with predentin, which mineralizes to become circumpulpal dentin. Mantle dentin forms the outer layer near the enamel.
- Dentinal tubules contain peritubular dentin and connect the
The document summarizes the stages of odontogenesis, or tooth development, from the dental lamina stage through root formation. It describes how during embryonic development, the dental lamina thickens to form tooth buds, which develop through bud, cap, and bell stages. During these stages, the enamel organ and dental papilla form. Odontoblasts then deposit dentin while ameloblasts deposit enamel. After crown formation, the root develops through the formation of the epithelial root sheath. Cementum is later deposited on the root surface by cementoblasts.
An odontoblast is a biological cell of neural crest origin whose main function is formation of dentin.
This slide gives a detailed explanation of the same.
Dentin is a hard yellowish substance that forms the bulk of teeth. It is composed of 70% hydroxyapatite crystals and 30% organic materials like collagen. Dentin is formed by odontoblasts cells differentiated from dental papilla cells. It determines the shape of teeth and contains microscopic tubules that house the processes of odontoblast cells. Dentin is harder than bone but softer than enamel. It has different layers with varying properties located at different regions of the tooth.
This document provides an overview of dentin, including:
- Its composition, formation process, and physical properties.
- The roles of odontoblasts and other components in dentinogenesis.
- The different types and structures of dentin, such as peritubular and intertubular dentin.
- Features like dentinal tubules, Von Ebner's lines, and the dentinoenamel junction.
- Its clinical significance, including use of the cementodentinal junction as a reference point in root canals.
- Potential developmental irregularities below the enamel-dentin junction that could predispose to caries.
The presentation discusses about tooth enamel in detail including its formation, characteristics, structure and histological features along with its clinical considerations. It is well supported with diagrams for better understanding of the text.
Suggestions and feedback will be well appreciated.
The document discusses the properties and development of dentin. It begins by introducing dentin and its role in tooth structure. Then it covers the physical and chemical properties of dentin, including its composition, hardness, thickness and density. The stages of dentin development and mineralization are described. Histologically, the key features of dentin are dentinal tubules, peritubular dentin, intertubular dentin and predentin. Structural lines like the dentinoenamel junction and Tome's granular layer are also outlined. Finally, the document notes different types of dentin like mantle dentin.
The document summarizes the development and growth of teeth from early formation in the embryo through the bell stage. It describes how the primary epithelial band forms and divides into the dental lamina and vestibular lamina. The dental lamina then goes through the bud, cap, and bell stages as it develops into the tooth germ and interacts with the underlying dental papilla and dental sac tissues to form the tooth structures. Key cellular and molecular signals that control tooth positioning and patterning are also discussed.
The dental pulp is the soft connective tissue inside teeth that gives them life. It develops from the dental papilla and occupies the central portion of teeth. The pulp contains blood vessels, nerves, fibroblasts, and odontoblasts - cells that produce dentin. With age, the pulp decreases in size and vascularity. It serves formative, protective, sensory, nutritive, and inductive functions. Precautions must be taken during cavity cutting to avoid damaging the pulp. Pulpitis is inflammation of the pulp, and root canal treatment removes inflamed or infected pulp tissue from teeth.
Dentin is the mineralized hard tissue that forms the bulk of the tooth beneath enamel and cementum. It is sensitive and continues to form throughout life at the expense of the pulp. Dentinogenesis begins when the dental papilla differentiates into odontoblasts. There are three stages of odontoblast development: differentiation, secretory formation of predentin and dentin, and a resting stage. Dentin is composed of hydroxyapatite crystals embedded in a collagen matrix. It has tubules that house odontoblast processes and dentinal fluid. The structure and composition of dentin provides strength and protection for the pulp.
Development Of Dentition & Occlusionjinishnath
The document discusses the development of dentition and occlusion from pre-natal development through post-natal development in humans. It covers:
- Pre-natal development of teeth including formation of the dental lamina and enamel organs.
- Stages of tooth development including bud, cap, and bell stages.
- Formation of the root and root sheath.
- Theories of tooth eruption.
- Post-natal development from birth through completion of primary dentition and the transitional periods involving eruption of permanent teeth.
The dental pulp is loose connective tissue located in the center of the tooth that contains blood vessels, nerves, and cells like odontoblasts. It has formative, nutritive, protective, and defensive functions. Over time, the pulp undergoes changes like decreased size and vascularity, increased calcification in the form of pulp stones or diffuse deposits, and reduced vitality.
Cementum is the mineralized tissue covering dental roots. It begins at the cementoenamel junction and continues to the root apex. Cementum provides attachment for collagen fibers (Sharpey's fibers) that bind the tooth to surrounding structures. Cementum develops in two stages: the prefunctional stage involving matrix formation and mineralization, and the functional stage where cementum deposition continues throughout life in response to tooth movement and wear. Cementum comes in various forms classified by development, cellularity, and fiber origin and includes acellular, cellular, intrinsic and extrinsic fiber cementum.
The document discusses the structure and composition of dental hard tissues, focusing on enamel. It describes enamel as the outermost rigid tissue that covers the tooth crown. Enamel is composed primarily of hydroxyapatite crystals arranged in rods that run from the dentin-enamel junction toward the outer surface. The rods are arranged to provide strength and withstand forces during chewing. Enamel hardness allows it to function in mastication but renders it brittle, requiring the underlying dentin as support.
The document summarizes the process of dentinogenesis or dentin formation. It involves differentiation of odontoblasts from dental papilla cells, secretion of an organic matrix, and mineralization of the matrix. Odontoblasts secrete collagen fibers and matrix vesicles that initiate mineralization. Dentin is formed in mantle dentin near enamel and circumpulpal dentin further inside via continuous mineralization. Root dentin formation begins after crown completion, guided by Hertwig's epithelial root sheath.
Tooth eruption involves three phases: pre-eruptive, eruptive, and post-eruptive. In the pre-eruptive phase, tooth germs develop and move within the jaw as it grows. The eruptive phase begins with root formation and ends when teeth reach the occlusal plane. Teeth emerge through the gums via bone resorption. In the post-eruptive phase, teeth continue moving axially and mesially to accommodate jaw growth and wear. Several theories attempt to explain eruption mechanisms, including root formation, bone remodeling, dental follicle activity, and periodontal ligament traction.
Dentin is the hard, bony tissue found in teeth beneath the enamel. It contains dentinal tubules that house odontoblastic processes and nerve fibers. Dentin is classified as primary, secondary, or tertiary depending on the time of its development. Primary dentin forms before and during eruption, secondary forms after root formation is complete, and tertiary dentin is produced in reaction to stimuli like attrition or caries. Tertiary dentin can be reactionary or reparative.
The document discusses the structure and development of the dental pulp. It begins by describing the pulp as a soft tissue composed of mesenchymal cells and specialized odontoblasts. The close relationship between odontoblasts and dentin results in the pulp-dentin complex. The primary role of the pulp is to produce dentin, but it also functions as a sensory organ. The document then proceeds to discuss pulp embryology and development, pulp anatomy and histology, innervation and sensitivity, aging changes, and other related topics.
Dentin is the mineralized tissue that forms most of the tooth. It is softer than enamel but harder than bone and cementum. Dentin consists of mineralized collagen and closely packed dentinal tubules that contain odontoblastic processes. Dentin is formed by odontoblasts, which deposit an organic matrix that then mineralizes. There are different types of dentin formed at various stages, including primary, secondary, and tertiary dentin formed in response to stimuli. The properties and microstructure of dentin can provide information in forensic dentistry applications.
This document provides information on dentin, including its composition, formation, and types. Some key points:
- Dentin makes up the bulk of the tooth and is composed of 65% inorganic material (mainly hydroxyapatite) and 35% organic material (collagen and proteoglycans).
- Odontoblasts are cells responsible for dentin formation. Their processes extend into dentinal tubules that permeate the dentin.
- Dentin formation begins with predentin, which mineralizes to become circumpulpal dentin. Mantle dentin forms the outer layer near the enamel.
- Dentinal tubules contain peritubular dentin and connect the
The document provides an overview of the pulp-dentin complex, including dentin and pulp. It discusses the physical and chemical properties of dentin, its structure including dentinal tubules and types of dentin. Dentinogenesis and age-related changes are also covered. The morphology, development, zones and cell types in pulp are summarized. The document establishes that dentin and pulp are embryologically, histologically and functionally the same tissue and should be considered as a complex.
The document summarizes key aspects of dentin:
- Dentin is a bonelike tissue that makes up the bulk of teeth beneath enamel. It contains dentinal tubules that branch throughout its thickness.
- Dentin's physical properties include a light yellow color that darkens with age and a hardness between enamel and bone. Chemically, it is composed mostly of hydroxyapatite and collagen.
- Histologically, dentin contains dentinal tubules, peritubular dentin surrounding the tubules, intertubular dentin between tubules, and incremental lines that indicate its growth. The tubule density is highest near the pulp.
Garima Singh presented on the topic of dentin. Key points included:
- Dentin is the tissue found underneath enamel and makes up the bulk of teeth. It contains dentinal tubules that contain odontoblast processes and connect the pulp chamber.
- Dentin is made up of 70% inorganic material (mainly hydroxyapatite), 20% organic material (mainly type I collagen), and 10% water. It undergoes dentinogenesis through collagen matrix formation and mineralization.
- There are different types of dentin, including primary, secondary, and tertiary dentin which are formed at different stages. Characteristics like tubule orientation and mineralization differ between primary and permanent dentin
Dentin is the hard, bony tissue found underneath the enamel of teeth. It is formed by odontoblast cells in a process called dentinogenesis, which occurs in two phases - organic matrix formation and mineralization. There are different types of dentin based on the time of formation (primary, secondary, tertiary) and relation to dentinal tubules (peritubular, intertubular, intratubular). Dentin contains dentinal tubules that contain odontoblast processes and nerves, and transmit sensations. Theories of dentin sensitivity include the direct nerve stimulation theory, transduction theory, and hydrodynamic theory which suggests that fluid pressure changes in dentinal tubules stimulate nerves to cause
middle layer of tooth the dentin which has yellowish in colorRenu710209
dentin is the resilient structure of tooth which gives yellowish color and protect the underlying dentalpulp and innervated structures from external stimuli
BDS first year Dentin presentation by SDM dRanAndSan
- Dentin forms the bulk of the tooth and determines its shape and size. It is a living tissue composed of hydroxyapatite crystals embedded in an organic matrix.
- Dentin varies in thickness from 3-10mm, with the buccal surface being the thickest. It is harder than bone but softer than enamel.
- Dentin's organic matrix contains collagen fibers, proteoglycans and glycoproteins. Inorganic components include hydroxyapatite crystals that are smaller than those in enamel.
An overview on the Pulp Dentin Complex .pptxperiovista
The document discusses the pulp-dentin complex. It describes dentin as the second layer of the tooth that provides structure and determines tooth shape. Dentin is a living tissue containing odontoblast processes in tubules. Dentin forms through secretion of an organic matrix followed by mineralization. Different types of dentin form throughout life. The pulp contains blood vessels, nerves and odontoblasts that form dentin. Dentin-pulp complex has sensory and protective functions.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
Dentin with emphasis on applied physiology and pathology Nadeem Aashiq
This document provides an overview of the structure and properties of dentin. It discusses the composition, physical properties, and microscopic structure of dentin. Key points include that dentin is composed of organic and inorganic materials, including collagen, water and hydroxyapatite crystals. It describes the arrangement of dentinal tubules and peritubular dentin. Primary, secondary and tertiary dentin formation is explained. The roles of odontoblasts and dentinal fluid are also summarized. The document considers age-related changes in dentin like dead tracts and sclerosis.
Pediatric Endodontics - Indirect and Direct pulp capping,Pulpotomy, Pulpecto...Karishma Sirimulla
this seminar consists of basis differences in root canal pattern between primary and permanet teeth followed by various definitions techniques and medicaments used in indirect pulp capping, direct pulp capping, pulpotomy, pulpectomy, apexogenesis and apexification
This document provides an overview of tooth development from the primary epithelial band through the various developmental stages including bud, cap and bell stages. It discusses the formation of the vestibular lamina, dental lamina and fate of the dental lamina. Key processes like dentinogenesis, amelogenesis, Hertwig's root sheath formation and root development are summarized. Developmental disorders affecting tooth size, shape, number and structure are also outlined. The document concludes by reviewing agents that can affect tooth development such as vitamin deficiencies and medications.
Dentin is the hard tissue that forms the bulk of the tooth beneath enamel. It consists of a bone-like matrix with dentinal tubules that contain odontoblast processes and nerves. Dentin is less mineralized than enamel but provides strength and protects the pulp. The three main theories of dentin hypersensitivity are direct neural stimulation, transduction, and the most accepted hydrodynamic theory, which proposes that fluid movement in the dentinal tubules causes mechanical stimulation of intratubular nerves when exposed dentin is subjected to stimuli.
This document discusses dentinogenesis, the formation of dentin by odontoblasts. It describes the different types of dentin formed at various stages - mantle dentin, primary dentin, secondary dentin, and tertiary dentin. It also discusses the regional distribution and structure of different zones of dentin, including mantle dentin, circumpulpal dentin, secondary dentin, tertiary dentin, predentin, interglobular dentin, and the granular layer of Tomes. Additionally, it compares intratubular and intertubular dentin, and provides notes on sclerotic dentin, dead tracts, incremental lines of Von Ebner and Andersen, lines of primary
This document provides an overview of the gingiva. It begins with definitions of gingiva from various sources and discusses the development, macroscopic features, microscopic features, fibers, cells, vascular supply, nerve supply, and matrix of the gingiva. Specifically, it describes the development of gingiva from mesoderm, its division into marginal, attached, and interdental papilla. It also discusses the layers of the gingival epithelium, the keratinization process, and cell types present like keratinocytes and non-keratinocytes.
Dentin is the mineralized tissue found underneath enamel that surrounds the dental pulp. It is composed mainly of hydroxyapatite crystals (70%) along with collagen (20%) and water (10%). Dentin formation (dentinogenesis) occurs in two stages - first, odontoblast cells secrete an unmineralized dentin matrix called predentin, then mineralization of the matrix occurs from the inside out in either a globular or linear pattern. Odontoblasts undergo differentiation, formation, and quiescence stages as they secrete predentin, retreat into the pulp canal leaving behind dentinal tubules, and reduce activity over time.
This document provides information about a seminar on enamel, dentin, and pulp presented by Dr. Ashish Kalhan. It discusses the key structures and properties of enamel, dentin, and pulp.
Enamel is the outermost covering of the tooth. It is the hardest tissue in the body and provides protection. It is made up of enamel rods arranged in a prism-like pattern. Dentin lies underneath the enamel and makes up the bulk of the tooth. It contains dentinal tubules that house odontoblast processes. The innermost living tissue is the pulp, which contains blood vessels, nerves, and odontoblasts.
The document discusses the physical and chemical properties of enamel
Thinking of getting a dog? Be aware that breeds like Pit Bulls, Rottweilers, and German Shepherds can be loyal and dangerous. Proper training and socialization are crucial to preventing aggressive behaviors. Ensure safety by understanding their needs and always supervising interactions. Stay safe, and enjoy your furry friends!
How to Manage Your Lost Opportunities in Odoo 17 CRMCeline George
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
MATATAG CURRICULUM: ASSESSING THE READINESS OF ELEM. PUBLIC SCHOOL TEACHERS I...NelTorrente
In this research, it concludes that while the readiness of teachers in Caloocan City to implement the MATATAG Curriculum is generally positive, targeted efforts in professional development, resource distribution, support networks, and comprehensive preparation can address the existing gaps and ensure successful curriculum implementation.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
2. CONTENTS
• INTRODUCTION
• PHYSICAL PROPERTIES
• CHEMICAL PROPERTIES
• STRUCTURES
• TYPES OF DENTIN
• INCREMENTAL LINES OF DENTIN
• INNERVATION OF DENTIN
• THEORIES OF PAIN TRANSMISSION THROUGH DENTIN
• AGE AND FUNCTIONAL CHANGES
• DEVELOPMENT OF DENTIN
• CLINICAL CONSIDERATIONS
• DEVELOPMENTAL DEFFECTS
4. • Dentin is the hard tissue of the tooth that surrounds the central core
of nerves and blood vessels and provides the bulk and general form
of the tooth
• Since it begins to form slightly before the enamel, it determines the
shape of the crown, including the cusps and ridges and the number
and size of roots
• Said to be a living tissue since the tubules present in it contains
processes of specialised cells, the odontoblast
5. PHYSICAL PROPERTIES
• In teeth of young individuals, the dentin is usually light yellowish in colour,
becoming darker with age.
• Dentin is viscoelastic and subject to slight deformation
• It is harder than bone but considerably softer than enamel
• The dentin of primary teeth is slightly less hard than that of permanent
teeth.
• The dentin is more radiolucent than enamel
6. PROPERTY VALUE
Colour Pale yellow
Thickness 3-10 mm
Modulus of Elasticity 15-20 GPa
Hardness 68 KHN
Carious Dentin 25 KHN
Sclerotic Dentin 80 KHN
Compressive strength 266 MPa
Tensile strength 50 MPa
Radiopacity Less than enamel
8. Organic (20%)
• The organic substance consists of collagenous fibrils embedded in the
ground substance of mucopolysaccharides
• Type I collagen is the principal type of collagen found in the dentin
• Ground substance:-
i. proteoglycans- chondroitin sulphates, decorin & biglycans
ii. Glycoproteins- dentin sialoprotein (DSP), osteonectin, osteopontin
iii. Phosphoproteins- dentin phosphoprotien (DPP), gamma
carboxyglutamate containing proteins and phospholipids.
• In addition, matrix contains growth factors like transforming growth factor
(TGF), fibroblast growth factor (FGF), insulin like growth factor (IGFs),
bone morphogenic proteins (BMPs), vascular endothelial growth factor
(VEGF), and angiogenic growth factor (AGF).
9. • Inorganic (65%)
• The inorganic component consist of hydroxyapatite.
• Each hydroxyapatite crystal is composed of several thousand unit cells.
• The crystals are plate shaped and much smaller than the hydroxyapatite
crystal in enamel.
• Dentin also contain small amounts of phosphates, carbonates, and sulfates.
• The crystals are poor in calcium but rich in carbon when compared to
enamel
11. DENTINAL TUBULE
• The course of the dentinal tubules follow a
gentle curve in the crown where it resembles
an S shape
• Starts at right angles at the pulpal surface,
the first convexity of this doubly curved
course is directed towards the apex of the
tooth
• These tubules end perpendicular to the DEJ
& CDJ
12. • It is almost straight near the root tip and along the incisal edges and cusps
• Dentin thickness ranges from 3-10mm or more
• No. of tubules per square millimetre varies from 15000
at the DEJ to 65000 at the pulp - density and diameter
increases with depth
13. • There are more tubules per unit area in the crown than in the root
• These dentinal tubules have lateral branches throughout dentin, which are termed
canaliculi or microtubules
• A few odontoblastic processes extend through the DEJ into the enamel several
millimetres. These are called Enamel Spindles
14.
15. PERITUBULAR DENTIN
• The dentin that immediately surrounds
the dentinal tubules is termed peritubular dentine
• Highly mineralized than intertubular dentin
(about 9%)
• Twice as thick in outer dentin (approx. 0.75μm)
than inner dentin(approx. 0.4μm)
16. • Studies with electron microscope show the
increased mineral density in the peritubular dentin
• Between the odontoblastic process and the
peritubular dentin, a space known as
periodontoblastic space is present.
• This space contain the dentinal fluid. The normal
flow of the fluid is outward from the pulp.
17. INTERTUBULAR DENTIN
• The main body of dentin is composed of intertubular dentin.
• Located between the dentinal tubules specifically between the zones of
peritubular dentin
• One half of its volume is organic matrix, specifically collagen fibers
18. • The fibrils range from 0.5-0.2μm in diameter and exhibit cross banding at
64μm intervals
• HA crystals are formed along the fibers with their long axis oriented parallel to
the collagen fibers
19. PREDENTIN
• Located adjacent to the pulp tissues
• 2-6μm, depending on the activity of odontoblast
• First formed dentin and is not mineralised
• The collagen fibres undergo mineralization at the
predentin - dentin JUNCTION, the predentin then
becomes dentin and a new layer of predentin forms
circumpulpally
20. DENTINO ENAMEL JUNCTION
• The DEJ is a complex and critical structure
uniting two dissimilar calcified tissues and acts
to prevent the propagation of cracks from
enamel into dentin.
• The DEJ has three level structure, 25-100 µm
scallops with their convexities directed
towards the dentin and concavities toward the
enamel; 2-5µm micro scallops and a smaller
scale structure.
• The convexities of the scallops are directed
towards the dentin. The concavities are
directed toward the enamel. The surface of the
dentin at DEJ is pitted.
21. ODONTOBLAST PROCESS
• Cytoplasmic extensions of the odontoblasts
• The odontoblasts reside in the peripheral pulp at
the pulp-predentin border and their processes
extend into the dentinal tubules
• The processes are largest in diameter near the
pulp and taper further into dentin
22. • The odontoblast cell bodies are approximately 7μm in
diameter & 40μm in length
• The junction between odontoblasts maybe of gap
juntions, tight junctions, and desmosomal junctions.
• The odontoblast process is composed of microtubules
of 20 µm in diameter and small filaments 5 to 7.5µm
in diameter.
DEJ
Odontoblast
ic process
Preodonto
blastic
space
Peritubular
dentin
Mantle
dentin
Circumpul
pal dentin
Predentin
Intertubu
lar dentin
Odontoblas
ts
25. PRIMARY DENTIN
• Dentin that is formed prior to eruption of a tooth, before root
completion
• Secreted at a relatively higher rate
• Constitutes major part of the dentin in the tooth
• Consist of mantle dentin and circumpulpal dentin.
26. 1) Mantle Dentine
• First formed dentin in crown underlying the DEJ
• 20 μm thick
• Fibrils found in this zone are perpendicular to DEJ
• Organic matrix - von korffs fibres (large diameter
fibrils- type III collagen fibrils)
• Less mineralized compared to circumpulpal dentin
27. 2) Circumpulpal Dentin
• Forms the remaining primary dentin or
bulk of the tooth.
• The fibrils are much smaller in diameter
(0.05micrometer) & are more closely
packed together.
• Slightly more mineral content than mantle
dentin.
28. SECONDARY DENTIN
• Formed after root completion
• Narrow band of dentin bordering the pulp
• Contains fewer tubules than primary dentin
• There is usually a bend in the tubules where
primary and secondary dentin interface
29. • Since it is formed after eruption, the odontoblasts
slightly change direction which contributes to
bending of dentinal tubules
• It is a slow continuous deposition of dentin.
• It is formed more slowly than primary dentin.
• Secondary dentin is not formed uniformly and
appears in great amounts on the roof and floor of
pulp chamber, where it protects pulp from exposure.
30. TERTIARY DENTIN
• Tertiary dentin is reparative, response, or reactive
dentin.
• This is localized formation of dentin on the pulp-
dentin border, formed in reaction to trauma such as
caries or restorative procedures.
• By pathologic process or operative procedures, the
odontoblastic processes are exposed or cut, the
odontoblasts die or survive, depending on the
extend of injury
31. • If they survive, dentin that is produced are
called reactionary or regenerated dentin
• Killed odontoblasts are replaced by the
migration of undifferentiated cells arising in
the deeper layers of the pulp to the dentin
interface
• This newly differentiated odontoblasts then
begin deposition of reparative dentin to seal
off the zone of injury as a healing process
initiated by the pulp,
32. • Resulting in resolution of the inflammatory process and removal of
dead cells
• This type dentin produced by a new generation of odontoblast-like
cells in response to appropriate stimulus after the death of original
odontoblasts is called Reparative dentin
• This reparative dentin has fewer and more twisted tubules than normal
dentin
• Histological difference between reactionary and reparative dentin is
that reactionary dentin is deficient in acid proteins so it doesn't stain.
36. 1) Incremental lines of von Ebner
• Also known as Imbrication line or short period line
• The incremental lines of Von Ebner or imbrications
lines appear as fine lines or striations in dentin
• Run at right angles to the dentinal tubules.
• These lines reflect the daily rhythmic, recurrent
deposition of dentin matrix as well as hesitation in the
daily formative process
37. • The distance between lines varies from 4-8
µm in the crown to much less in the root. The
daily increment decreases after a tooth
reaches a functional occlusion
• The course of the lines indicates the growth
pattern of the dentin
• Cuspal dentin- 4 µm/day
• Root dentin- 2 µm/day
38. 2) Contour lines of Owens
• Some of the incremental lines are
accentuated because of disturbances in the
matrix and remineralisation process. Such
lines are known as contour lines of Owen
• These lines represent hypocalcified bands
39. 3) Neonatal line
• In the deciduous teeth and in the first
permanent molars, the prenatal and
postnatal dentin is separated by an
accentuated contour line, this is termed
the Neonatal line.
• This line reflects the abrupt change in
environment that occurs at birth .
• The dentin matrix formed prior to birth is
usually of better quality than that formed
after birth
40. 4) Andersons line
• Also known as long period line
• The term long period refers to the intrinsic
temporal repeat interval that is greater than one
day (in contrast to daily short period line). 16-
20um apart
• Between each long period line there are 6 - 10
pairs of short period lines.
• Cause for the 6 to 10 day periodicity is unknown.
41. GRANULAR LAYER
• There is a zone adjacent to the
cementum that appears granular
known as Tome's granular layer
• It slightly increases in amount from
the CEJ to the root apex
• Caused by coalescing and looping of
the terminal portions of the dentinal
tubules
42. INNERVATION OF DENTIN
•INTRATUBULAR NERVE
• Nerve fibers were shown to accompany 30 to 70% of
the odontoblastic process and these are referred to as
intratubular nerves
• Dentinal tubules contain numerous nerve endings in
the pre dentin and inner dentin no farther than 100 to
150 µm from the pulp
• Most of these small vesiculated endings are located in
tubules in coronal zone, specifically in the pulp horn.
43. THEORIES OF PAIN
TRANSMISSION THROUGH
DENTIN
Basic theories of pain conduction through dentin
• Direct neural stimulation
• Transduction theory
• Hydrodynamic theory
44. Direct Neural Stimulation
• According to which nerves in the dentin get stimulated.
Drawbacks:
• The nerves in dentinal tubules are not commonly seen and even if they are
present, they do not extend beyond the inner dentin
• Topical application of local anaesthetic agents do not abolish sensitivity
• Hence this theory is not accepted
45. Transduction Theory
• According to which the odontoblasts process is the primary structure
excited by the stimulus and that the impulse is transmitted to the nerve
endings in the inner dentin.
Drawback:
• Since there are no neurotransmitter vesicles in the odontoblast process
to facilitate the synapse or synaptic specialization
46. Hydrodynamic theory
Most accepted theory
• Various stimuli such as heat, cold, airblast
dessication or mechanical or osmotic
pressure affect fluid movement in the
dentinal tubules.
• This fluid movement either inward or
outward, stimulates the pain mechanism
in the tubules by mechanical disturbance
of the nerves closely associated with the
odontoblast and its process
• Thus these endings may act as
mechanoreceptos as they are affected by
mechanical displacement of tubular fluid
47.
48. AGE AND FUNCTIONAL CHANGES
Vitality of dentin
• Odontoblasts and its processes are an integral part of dentin
• And so vitality is understood to be the capacity of the tissue to react to
physiologic and pathologic stimuli, dentin must be considered a vital
tissue
49. • Dentinogenesis is a process that continues through out life
• Although after the teeth have erupted and have been functioning for a short
time, dentinogenesis slows and further dentin formation is at a slower rate.
This is secondary dentin
• Pathologic changes in dentin such as dental caries, abrasion, attrition or the
cutting of dentin in operative procedures cause changes in dentin. They are
the dead tracts, sclerosis and the addition of reparative dentin
50. 1) Dead tracts
• In dried ground section the odontoblastic
processes disintegrate and the empty tubules
are filled with air
• Appear black in transmitted light and white
in reflected light
• Degeneration is often observed in areas of
narrow pulp horns because of crowding of
odontoblasts
51. • These degenerated empty areas
demonstrate decreased sensitivity
• Seen to a greater extend in older
teeth
• Dead tracts are probably the
initial step in the formation of
sclerotic dentin
53. 3) Sclerotic dentin
• Caries, attrition, abrasion, erosion or cavity
preparation causes collagen fibres and
apatite crystals to begin appearing in the
dentinal tubules
• This blocking of tubules may be considered
as a defensive reaction of dentin
• These apatite crystals are initially only
sporadic in a dentinal tubule but gradually
fill it with a fine meshwork of crystals
54. • As this continues, the tubule lumen is
obliterated with mineral which appears
very much like the peritubular dentin
• Dentin in such areas become transparent
• Transparent in transmitted and dark in
reflected light
• There is decreased permeability of
dentin
56. DENTINOGENESIS
• Formation of dentin is called dentinogenesis, it starts before
amelogenesis
• Dentin is formed by odontoblast cell
• It takes place in two phases, first the formation of organic collagen
matrix and second, the deposition of hydroxyapatite crystal
57. • Dentin formation begins when the tooth germ
has reached bell-stage of development.
• Under the influence of inner enamel
epithelium, the outermost ectomesenchymal
cells of dental papilla differentiate into
odontoblasts.
• Initially, the cells of the dental papilla are
small, undifferentiated and have few
organelles.
58.
59. • Inner enamel epithelium releases transforming growth factor, insulin growth
factor and bone morphogenetic protein for the differentiation of odontoblasts.
• Differentiation begins adjacent to the deepest invagination of the enamel
organ, the portion of the future cusp tip.
• The cells of dental papilla immediately adjoining the acellular zone enlarge to
become preodontoblasts, which change their shape from ovoid to columnar
and differentiate into odontoblasts.
• The nucleus is oriented towards the base (away from the inner enamel
epithelium) and increased amounts of protein- synthesizing organelles appear
in cytoplasm.
60.
61. MATRIX FORMATION
• Matrix formation begins with the appearance of large diameter collagen
fibrils (0.1-0.2 micrometres) known as Vonkroff's fibres.
• These fibres are laid down at right angles to the future DEJ.
• Once the mantle dentin is laid, the remaining collagen fibres are laid
parallel to the DEJ.
• As the odontoblast forms the matrix and move towards the pulp, several
fibres join to form the processes that are embedded in the dentinal tubules
62. • Dentin is formed at a rate of about 4 micrometres/day till the crown is
formed and the tooth erupts. After this the dentin production slows to
about 1µm/day
• As each increment of the matrix is formed, it remains for a day before
it is calcified and the next increment of the matrix forms.
• The rate of matrix formation is slower in the radicular dentin and it
contains collagen fibres which is parallel to the CEJ.
63.
64. Formation of pre dentin
• The first indication of pre dentin formation is the development of
bundles of fibrils among the fully differentiated odontoblast
• These bundles are known as Von korff’s fibers, that form the major
component of the of the first formed thickness of dentin
• Are attached to the basement membrane of inner enamel epithelim
65. MINERALIZATION
• First crystal deposition is in form of very fine plates of hydroxyapatite on the surface of
collagen fibrils and in the ground substance.
• The crystal associated with collagen fibrils are arranged in an orderly fashion, with their
long axis paralleling the fibril long axis and in rows conforming to the 64 nm striation
pattern
• Mineralization usually occurs by matrix vesicle in which odontoblast release membrane
bound vesicles into the organic matrix.
• The general calcification process is gradual, but the peritubular region becomes highly
mineralised at very early stage
66. • The apatite crystal of dentin resemble those found in bone and
cementum. They are 300 times smaller than those formed in
enamel.
• Dentin sialoprotein present in mineralizing dentin affects the
rate of mineral deposition while other proteoglycans present
more in predentin, inhibits premature calcification of the
predentin
• Many genes are implicated in dentinogenesis, the newer ones
being MAP1B for odontoblast differentiation, and PHEX for
dentin mineralization.
67.
68. • Several proteins are released to regulate the deposition of minerals.
• OSTEONECTIN - it can inhibit hydroxyapatite crystals growth & promote Calcium
& phosphorous binding to collagen
• OSTEOPONTIN - promotes mineralization
• DPP (Dentin phosphoproteins) concentration elevated - inhibits mineralization
• CHONDROITIN SULPHATE - properties vary depending on whether they are in:
PREDENTIN - prevent transport and diffusion of crystals(inhibitors)
MINERALIZING DENTIN -promote hydroxyapatite crystal formation.
69. CLINICAL CONSIDERATIONS
Exposure of Dentinal Tubules
• tooth wear, fractures, caries, cavity cutting procedures etc. lead to exposure of
dentinal tubules.
• 1 mm exposed dentin damages 30000 living odontoblasts
• The rapid penetration and spread of caries in the dentin is the result of tubule
system in the dentin
70. • The dentinal tubules provide a passage for invading bacteria and their
products through either thick or thin dentinal layer.
• Advised to seal dentin surface with nonirritating, insulating substance
such as bonding agents, varnishes or restoration
71. Dentinal Hypersensitivity
• Short, sharp pain arising from exposed dentin in response to a stimuli
typically thermal, evaporative, tactile, osmotic or chemical and which can’t
be ascribed to any other form of dental defect or pathology.
• The sensitivity of the dentin has been explained by the hydrodynamic
theory, that alteration of the fluid and cellular contents of the dentinal
tubules causes stimulation of the nerve endings in contact with these cells.
• Most pain inducing stimuli increase fluid flow within the dentinal tubule,
giving rise to a pressure change throughout the entire dentin
• This in turn activates the intra dentinal nerves at the pulp-dentinal interface,
or within the dentinal tubules thereby generating pain.
72. • ETIOLOGY-
a) Exposure of dentinal tubules
b) Loss of enamel
c) Attrition, abrasion and erosion
d) Loss of cementum
e) Gingival recession
• MANAGEMENT-
a) Block the dentinal tubule
b) First line of treatment- use of dentifrices containing potassium nitrate/ stannous
fluoride.
c) Lasers have been used in the treatment of hypersensitivity.
73.
74. Smear layer and smear plugs
• smear layer- term most often used to describe the
grinding debris left on dentin by cavity preparation
• Cutting debris when forced into dentinal tubules, it
forms plugs known as smear plugs
• Smear layer- 1-3 µm; smear plug- 40µm
• Significance- lowers the permeability of dentin
surface and occludes the tubule
• Disadvantage: prevents the adhesion of restorative
materials in the dentin
• Therefore this layer has to be removed by etching and
a rough porous surface should be created for bonding
agent to penetrate
76. OPERATIVE INSTRUMENTATION
• Avoid- excessive cutting, heat generation, continuous drying
• Use- air-water coolant, sharp hand instruments
• Tungsten carbide burs to cut vital dentin, less heat generation.
77. DEVELOPMENTAL DEFFECTS
1. Dentinogenesis imperfect
• Group of hereditary conditions charecterised by abnormal dentin formation
• It is an autosomal dominant condition.
• This condition causes tooth to be discoloured and translucent
• It can affect both primary teeth and permanent teeth
• Divided into:-
1) Type 1 – occurs with osteogenesis imperfect
2) Type 2 – hereditary opalescent dentin
3) Type 3 – brandywine isolate
78.
79. CLINICAL FEATURE:-
• Tulip shaped teeth, bluish grey- yellow/brown translucent
• Enamel chips away- exposed dentin, rapid attrition
• Amber appearance, excessive wear, multiple pulp exposures.
• The tooth usually involved and more severely affected are deciduous
teeth in type 1whereas in type 2, both the dentition are equally
affected.
• Radiographically, the teeth appears solid, lacking pulp chambers and
root canal.
80. TREATMENT
• In patient with DI, one must first be certain which type he/she are dealing
with.
• Severe cases of DI type 1 associated Osteogenesis imperfecta can present
significant medical management problems. Careful review of the patient's
medical history will provide clues as to the severity of bone fragility based
on the number of previous fractures and which bones were involved.
• Patients not exhibiting enamel fracturing , rapid wear crown placement and
routine restorative techniques may be used.
81. • Bonding of veneers may be used to improve the esthetics
• In more severe cases, where there is significant enamel fracturing and rapid
dental wear, the treatment of choice is full coverage crowns.
• However in case of DI 3 with thin roots are not good cases for full coverage
because of cervical fractures
• Occlusal wear with loss of vertical dimension:-
metal casting
newer composite
82. 2. DENTIN DYSPLASIA
• Rootless teeth
• Rare Dental Anomaly
• Normal Enamel, Atypical Dentin, Abnormal Pulp Morphology
• CLASSIFICATION: (Acc. To WHITKOP) -
a) TYPE I- RADICULAR
b) TYPE II - CORONAL
83. DENTIN DYSPLASIA TYPE 1
• Radicular dentin dysplasia
• Characterized by :-
• Both dentition are affected
• Normal appearing crown
• No or only rudimentary root
development
• Incomplete or total obliteration of pulp
chamber
• Teeth may exhibit extreme mobility
and exfoliate prematurely
DENTIN DYSPLASIA TYPE 2
• Coronal dentin dysplasia
• Characterized by :-
• Deciduous teeth have yellow, brown or
bluish grey appearance.
• Partial pulp obliteration
• Flame shaped coronal pulp chamber
• thread like root canals
• Usually the absence of periapical
radiolucencies
• Teeth roots are of normal shape and
contour
84. Management
• Preventive care is of most importance
• Directed towards specific symptoms that are apparent in each individual
• Recommended treatment- regular monitoring by dentist and preventive
dental care.
• Conventional endodontic therapy will require mechanical creations of pulp
path
85. 3. DENS EVAGINATUS
• Cusp like elevation of enamel located in
central groove or lingual ridge of the
buccal cusp of premolar or molar
• Consist of enamel and dentin with pulp
present in half of the cases
• Radiographically the occlusal surface
exhibits a tuberculate appearance and
often pulpal extension is seen in cusp.
• Occlusal problem which leads to pulpal
death
• Removal of cusp is indicated
86. 4. DENS IN DENTE
• Dentin and enamel forming tissue
invaginate the whole length of tooth
• Arise as a result of an invagination in
surface of tooth crown before the
calcification.
• Most frequently involved – maxillary
lateral incisor.
• Radiographically – “tooth within tooth”
• Food lodges in the cavity to cause caries
which rapidly penetrates the distorted
pulp chamber
• To prevent caries, pulp infection and
premature loss of tooth, the condition
must be recognized early and the tooth
should be prophylactically restored.
87. MANAGEMENT OF CHILDREN WITH
DEVELOPMENTAL DEFECT OF DENTIN
• Early diagnosis and preventive care are essential for successful
management of dentin defects
• Children who have family history of dentine defects such as
dentinogenesis imperfecta or those associated with medical conditions
known to be associated with dentin defect should be screened early
for dental problems
• As DI is associated with rapid tooth wear and crown fracture,
protection from tooth wear is recommended soon after eruption.
• Prophylactic coverage of tooth is necessary to protect the pulp soon
after eruption
Seow WK. developmental defects of enamel and dentine: challenges for basic science research and clinical management. Aust
Dent J. 2014 Jun; 59 Suppl 1:143-54. doi: 10.1111/adj.12104. Epub 2013 Oct 27. PMID: 24164394
88. REFERENCES
• Orban’s oral histology and embryology – G.S Kumar – Thirteenth edition. P93 -
116
• Ten Cate’s oral histology – development, structure and function – Antonio Nanci –
Sixth edition. P67 - 98
• Pathways of pulp – Cohen. Hargreaves – Ninth edition. P113-117
• Shafer’s Textbook of Oral Pathology – Shafer, Hine, Levy – 8th edition. P38 - 61
• Oral and Maxillofacial pathology – Neville – Third edition. P64-78
• The art and science of Operative dentistry – Theodore Sturdevant – Fourth edition
• Manual of Oral Histology and Oral Pathology – Maji Jose – Second edition. P35 –
43.
• Seow WK. developmental defects of enamel and dentine: challenges for basic
science research and clinical management. Aust Dent J. 2014 Jun; 59 Suppl
1:143-54. doi: 10.1111/adj.12104. Epub 2013 Oct 27. PMID: 24164394