The document provides information about the muscles of mastication. It defines masticatory muscles as the muscles that elevate the mandible to close the mouth. There are four primary muscles - temporalis, masseter, medial pterygoid, and lateral pterygoid. The document describes the origin, insertion, innervation, blood supply, functions, and clinical significance of each of these muscles. It also discusses accessory muscles like mylohyoid, geniohyoid, and anterior belly of digastric. The document emphasizes the importance of understanding masticatory muscles for dental treatments.
Anatomy of mandible and its importance in implant placementDr Rajeev singh
This document discusses the anatomy and importance of the mandible in implant placement. It begins by defining the mandible and its embryological development. It then describes the osteology and features of the body, rami, processes, borders and attachments in detail. It discusses the blood supply, nerve supply and growth of the mandible postnatally. Finally, it explains the applied anatomy of the mandible and importance of anatomical structures like the mandibular foramen, inferior alveolar canal, mental foramen and nerve, and mandibular incisive canal in safe implant placement.
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.for more details please visit
www.indiandentalacademy.com
Description :
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.for more details please visit
www.indiandentalacademy.com
This document discusses fractures of the mandibular condyle. It begins with an introduction and overview of the surgical anatomy and classification of condylar fractures. It then covers the etiology, diagnosis, and management of these fractures. Key points include that condylar fractures account for 20-30% of mandibular fractures. Diagnosis involves clinical examination, radiological imaging like CT scans, and the fractures can be classified in various ways. Management involves either conservative treatment with immobilization or functional exercises, or surgical treatment depending on the type and severity of the fracture. The document provides details on techniques, indications, and advantages/disadvantages of different treatment approaches.
Growth and Development of Craniofacial Complex IIAU Dent
This document summarizes a lecture on craniofacial growth and development. It discusses how the cranium and face grow, defining growth and development. Growth occurs through intramembranous bone formation or endochondral bone formation at sutures and synchondroses. Factors like bone growth, soft tissues, occlusion forces, and skeletal patterns influence occlusion development. The cranial vault completes growth by age 8 while the cranial base continues growing into the 20s. The face grows rapidly in depth initially and its growth is mostly complete by ages 16-18 for the upper face and 20-25 for the mandible.
The document discusses the trigeminal nerve (CN V), which has three main divisions - the ophthalmic, maxillary, and mandibular nerves. It describes the anatomy and branches of each division. The ophthalmic nerve is the smallest and is wholly sensory. It has three branches - the lacrimal, frontal, and nasociliary nerves. The maxillary nerve is the second division and is also wholly sensory. It has several branches including the zygomatic and posterior superior alveolar nerves. The mandibular nerve is the third and largest division and has both sensory and motor components.
Anatomy of mandible and its importance in implant placementDr Rajeev singh
This document discusses the anatomy and importance of the mandible in implant placement. It begins by defining the mandible and its embryological development. It then describes the osteology and features of the body, rami, processes, borders and attachments in detail. It discusses the blood supply, nerve supply and growth of the mandible postnatally. Finally, it explains the applied anatomy of the mandible and importance of anatomical structures like the mandibular foramen, inferior alveolar canal, mental foramen and nerve, and mandibular incisive canal in safe implant placement.
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.for more details please visit
www.indiandentalacademy.com
Description :
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.for more details please visit
www.indiandentalacademy.com
This document discusses fractures of the mandibular condyle. It begins with an introduction and overview of the surgical anatomy and classification of condylar fractures. It then covers the etiology, diagnosis, and management of these fractures. Key points include that condylar fractures account for 20-30% of mandibular fractures. Diagnosis involves clinical examination, radiological imaging like CT scans, and the fractures can be classified in various ways. Management involves either conservative treatment with immobilization or functional exercises, or surgical treatment depending on the type and severity of the fracture. The document provides details on techniques, indications, and advantages/disadvantages of different treatment approaches.
Growth and Development of Craniofacial Complex IIAU Dent
This document summarizes a lecture on craniofacial growth and development. It discusses how the cranium and face grow, defining growth and development. Growth occurs through intramembranous bone formation or endochondral bone formation at sutures and synchondroses. Factors like bone growth, soft tissues, occlusion forces, and skeletal patterns influence occlusion development. The cranial vault completes growth by age 8 while the cranial base continues growing into the 20s. The face grows rapidly in depth initially and its growth is mostly complete by ages 16-18 for the upper face and 20-25 for the mandible.
The document discusses the trigeminal nerve (CN V), which has three main divisions - the ophthalmic, maxillary, and mandibular nerves. It describes the anatomy and branches of each division. The ophthalmic nerve is the smallest and is wholly sensory. It has three branches - the lacrimal, frontal, and nasociliary nerves. The maxillary nerve is the second division and is also wholly sensory. It has several branches including the zygomatic and posterior superior alveolar nerves. The mandibular nerve is the third and largest division and has both sensory and motor components.
The document discusses two techniques for mandibular nerve blocks - the Gow-Gates technique and the Vazirani-Akinosi closed mouth mandibular block. The Gow-Gates technique provides anesthesia to all branches of the posterior division and buccal nerve, anesthetizing the mandibular teeth to midline. The Vazirani-Akinosi block is useful for patients with limited mouth opening, anesthetizing the inferior alveolar, mental, incisive, lingual, and mylohyoid nerves. Both techniques involve inserting a needle at specific landmarks to deposit local anesthetic in the target area. Proper administration results in numbness of the lip and tongue with
The document provides an overview of the anatomy, development, and surgical anatomy of the temporomandibular joint (TMJ). It discusses the key components of the TMJ, including the mandibular condyle, articular surfaces of the temporal bone, articular disc, fibrous capsule, and ligaments. It describes the development of the TMJ from two distinct blastemas beginning in the 7th week in utero. The document highlights several unique features of the TMJ, such as its articular surface being covered by fibrocartilage instead of hyaline cartilage. It also reviews the movements, vascular supply, innervation, and age-related changes of the TMJ.
Dr. Ahmed M. Adawy, Professor Emeritus, Dep. Oral & Maxillofacial Surgery. Former Dean, Faculty of Dental Medicine, Al-Azhar University. Condylar fractures represent one of the most controversial issues in maxillofacial traumatology regarding classification, diagnoses and therapeutic management. Classification systems of condylar fracture is discussed. Diagnosis is usually based on history clinical examination and radiographic finding. Treatment ranges from observation, jaw exercises to closed or opened interventions. For years closed reduction was thought to be essentially complication-free. Several serious complications however have been reported including temporomandibular joint ankyloses, malocclusion, mandibular deviation and the generative joint pathology. The absolute and relative indications for open reduction is given. The debate between supporters of open or closed reduction is still continuing and the issue has not been resolved. However, the final choice treatment modality should takes into account the location of the fracture, age of the patient, presence or absence of other associated injuries, cosmetic impact of the surgery and presence of other systemic medical conditions.
This presentation contains the detailed description about the courses, branches and supply of the Trigeminal Nerve, contains variations of maxillary nerve & Mandibular Nerve, and the detail about trigeminal Neurolgia and its managements
The trigeminal nerve is the largest cranial nerve with both motor and sensory components. It has three main divisions - ophthalmic, maxillary, and mandibular. The motor root originates in the pons and supplies muscles of mastication. The sensory root contains sensory fibers and divides into the three divisions. The ophthalmic nerve innervates the eye and parts of the face. The maxillary nerve innervates parts of the face, nasal cavity and palate. The mandibular nerve has motor fibers that innervate muscles of mastication and a large sensory component that provides sensation to parts of the face and oral cavity.
The document discusses the anatomy and branches of the mandibular nerve, including its course, distribution, and supply. It describes various anesthetic techniques for blocking branches of the mandibular nerve, including the inferior alveolar nerve block, lingual nerve block, buccal nerve block, and mental nerve block. It also discusses potential local complications from anesthetic techniques such as needle breakage, prolonged anesthesia, and soft tissue injury.
IS THE SCHNEIDERIAN MEMBRANE THICKNESS AFFECTED BY PERIODONTAL DISEASE? Shilpa Shiv
1) The study found that the thickness of the Schneiderian membrane, which lines the maxillary sinus, was significantly greater in patients with periodontally diseased maxillary molars compared to patients with edentulous areas.
2) While a smaller bone layer separating root tips from the sinus floor was associated with increased membrane thickness, no clear relationship was found between membrane thickness and clinical periodontal parameters.
3) The results indicate that cone-beam computed tomography can be useful for evaluating soft tissue conditions like Schneiderian membrane thickness in the maxillary sinus.
This presentation is done by Prof. Ahmed M. Adawy, Professor Emeritus, Dep. Oral & Maxillofacial Surg., Former Dean, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt.
The presentation is about the chapter of Temoromandibular Joint in Oral Surgery which includes definition, anatomy, diseases and its surgical treatment.
The mandible or lower jaw, is the largest & strongest bone of the face. The word “Mandible” is derived from Greek word
“mandere” – to masticate or chew. The Latin word “ mandibula” – lower jaw. It is horse-shoe shaped & the only movable bone of skull. Growth and development of an individual is divided into two periods Prenatal period and Post natal period. The first structure to develop in the primodium of the lower jaw is the mandibular division of trigeminal nerve that precedes the mesenchymal condensation forming the first [mandibular] arch. Endrocondral bone formation is seen in The condylar process, The coronoid process and The mental process. OUTER SURFACE OF MANDIBLE
1. External oblique line - origin to buccinator, depressor inferioris, depressor anguli oris.
2. Incisive fossa - origin of mentalis, mental slips of orbicularis oris.
3. Lateral surface of ramus - insertion for masseter.
4. Lower border - deep cervical fascia and platysma.
5. Postero-superior lateral surface of ramus - parotid gland.
6. Lateral surface of neck - attachment to lateral ligament of temperomandibular joint , parotid gland.
INNER SURFACE OF MANDIBLE
1. Mylohyoid line - origin to mylohyoid muscle , attachment to superior constrictor of pharynx, pterygomandibular raphae.
2. Medial surface of ramus - medial pterygoid muscle attachment.
Superior genial tubercles – genioglossus.
3. Inferior genial tubercles – origin to geniohyoid.
4. Lingula - sphenomandibular ligament.
5. Apex of coronoid process - temporalis attachment.
6. Pterygoid fovea - lateral pterygoid muscle.
7. Diagastric fossa - anterior belly of diagastric.
ARTERIAL SUPPLY OF MANDIBLE:
It is mainly divided into 2 categories :
1. Endosteal/ Central blood supply
2. Periosteal/ Peripheral blood supply
Central blood supply is via Inferior Alveolar Artery except the coronoid process which is supplied by Temporalis muscle vessels.
Inferior alveolar artery arises from maxillary artery which in turn is a branch of External carotid artery.
Inferior alveolar artery branches :
Lingual branch
Mylohyoid branch
Incisive branch
Mental branch
Peripheral blood supply is mainly via Periosteum via the nutrient vessels those penetrate the cortical bone and anastamose with the branches of Inferior alveolar artery.
VENOUS SUPPLY OF MANDIBLE
Drains into Internal Jugular vein and External Jugular vein through Maxillary vein, Facial vein and pterygoid plexus.
This document provides an overview of model analysis for mixed dentition. It defines study models and their objectives. Various types of model analyses are described, including those for mixed dentition like Moyer's analysis, which uses measurements of erupted mandibular incisors to estimate the sizes of unerupted canines and premolars. The goals and procedures of mixed dentition analysis are outlined, such as determining if there is enough space for permanent teeth. Factors considered include tooth sizes, arch perimeter, and expected changes during development.
Maxillofacial Surgery
Dental Students Fifth Year First semester
Lecture Name maxillofacial trauma part 2
Al Azhar University Gaza Palestine
Dr. Lama El Banna
The document discusses the anatomy of the mandible including the muscles of mastication, temporomandibular joint, nerve supply, and classifications of fractures. It examines the physical exam for mandibular fractures including assessing occlusion, trismus, and neurovascular status. Finally, it reviews treatment principles and options for mandibular fractures including maxillomandibular fixation, open reduction with rigid or non-rigid fixation, and external pin fixation.
This seminar explains about the development, relations, ligaments, various attachments, vascular and nervous supply and various surgical approaches and its modifications to TMJ
The document discusses growth and development of the maxilla from prenatal to postnatal periods. It describes how the maxilla develops from maxillary processes in the embryo. During prenatal growth, the maxilla is displaced downward and forward as the cranial base grows. Postnatally, the maxilla grows through bone deposition, remodeling at sutures, and expansion of the maxillary sinus. The primary palate develops early from the median palatine process, while the secondary palate forms from the palatine shelves fusing in the midline.
Growth and Development of Craniofacial Structure, Dentition and OcclusionHermie Culeen Flores
The document discusses growth and development of craniofacial structures, dentition, and occlusion. It covers:
- Mechanisms of bone growth including endochondral and intramembranous formation.
- Hypotheses of craniofacial growth including genetic and functional theories.
- Development of specific craniofacial regions like the cranial vault, basicranium, and nasomaxillary complex.
- Eruption sequences and development of the primary and permanent dentitions from prenatal to postnatal stages.
- Characteristics and phases of the mixed and permanent dentitions.
- Static and dynamic aspects of occlusion and types of occlusion like ideal, normal, and functional.
This document provides an overview of internal derangements of the temporomandibular joint (TMJ). It defines internal derangement as an abnormal relationship between the articular disc and condyle. The most common type is anterior disc displacement, which can be with or without reduction. Causes include trauma, functional overloading, joint laxity, and muscle spasms. Symptoms vary depending on the type but may include clicking, limited opening, and pain. Diagnosis involves clinical exams and MRI imaging. Treatment ranges from splint therapy to arthrocentesis or arthroscopy for lavage and relief of adhesions. Arthrocentesis is shown to improve opening and reduce pain by removing inflammatory factors from the
This document provides instructions for making final impressions for complete dentures, including custom tray fabrication, border molding techniques, and using selective pressure to record tissues in an undisplaced position. It describes areas that require special attention for the maxillary and mandibular impressions, such as the posterior palatal seal and retromylohyoid space. The goal is to make impressions that provide maximum coverage, close adaptation, and proper support and retention for the dentures.
The trigeminal nerve is the largest of the cranial nerves. It has both sensory and motor fibers. It has three main divisions - the ophthalmic, maxillary, and mandibular nerves. The ophthalmic nerve innervates parts of the face around the eyes. The maxillary nerve innervates parts of the face around the nose and mouth. The mandibular nerve is mixed and innervates muscles of mastication as well as parts of the face, tongue and mouth.
The maxillary nerve is the second division of the trigeminal nerve. It originates in the trigeminal ganglion and passes through the middle cranial fossa, pterygopalatine fossa, and orbit. In the pterygopalatine fossa, it gives off branches and connects to the pterygopalatine ganglion, the largest parasympathetic ganglion, which relays secretomotor fibers to glands of the nose, palate, and pharynx. The maxillary nerve and its branches provide sensory innervation to the face and motor input to the lacrimal gland.
Seminar on prenatal & postnatal development of maxillaDr . Arya S Kumar
This document discusses the prenatal and postnatal development of the maxilla. It begins by defining growth and development, and discussing the importance of understanding craniofacial growth. During the prenatal period, the maxilla develops from the maxillary process of the first branchial arch. Intramembranous ossification begins in the 8th week. The palatal shelves develop and later elevate into a horizontal position to fuse, forming the secondary palate. Postnatally, the maxilla continues growing through processes like cortical drift and growth at sutures. Understanding normal maxillary development is important for comprehending abnormalities.
This document discusses the muscles of mastication. It begins by defining mastication and describing the development of muscles from embryonic tissues. The primary muscles of mastication - masseter, temporalis, lateral pterygoid, and medial pterygoid - are then described in detail, including their origins, insertions, nerve/blood supply, and actions. Secondary muscles like the digastric, mylohyoid, and geniohyoid that assist in mastication are also outlined. The document concludes that the masticatory system requires precise muscle movement to effectively move the teeth during function.
The document discusses the muscles of mastication. There are 4 primary muscles - masseter, temporalis, lateral pterygoid, and medial pterygoid. These muscles develop from the first brachial arch and are innervated by the mandibular nerve. They work together to power the chewing cycle and move the mandible during opening, closing, and side-to-side motions. Secondary muscles like the digastric, mylohyoid, and geniohyoid can assist during difficult chewing. Conditions like tetanus and bruxism are also reviewed.
The document discusses two techniques for mandibular nerve blocks - the Gow-Gates technique and the Vazirani-Akinosi closed mouth mandibular block. The Gow-Gates technique provides anesthesia to all branches of the posterior division and buccal nerve, anesthetizing the mandibular teeth to midline. The Vazirani-Akinosi block is useful for patients with limited mouth opening, anesthetizing the inferior alveolar, mental, incisive, lingual, and mylohyoid nerves. Both techniques involve inserting a needle at specific landmarks to deposit local anesthetic in the target area. Proper administration results in numbness of the lip and tongue with
The document provides an overview of the anatomy, development, and surgical anatomy of the temporomandibular joint (TMJ). It discusses the key components of the TMJ, including the mandibular condyle, articular surfaces of the temporal bone, articular disc, fibrous capsule, and ligaments. It describes the development of the TMJ from two distinct blastemas beginning in the 7th week in utero. The document highlights several unique features of the TMJ, such as its articular surface being covered by fibrocartilage instead of hyaline cartilage. It also reviews the movements, vascular supply, innervation, and age-related changes of the TMJ.
Dr. Ahmed M. Adawy, Professor Emeritus, Dep. Oral & Maxillofacial Surgery. Former Dean, Faculty of Dental Medicine, Al-Azhar University. Condylar fractures represent one of the most controversial issues in maxillofacial traumatology regarding classification, diagnoses and therapeutic management. Classification systems of condylar fracture is discussed. Diagnosis is usually based on history clinical examination and radiographic finding. Treatment ranges from observation, jaw exercises to closed or opened interventions. For years closed reduction was thought to be essentially complication-free. Several serious complications however have been reported including temporomandibular joint ankyloses, malocclusion, mandibular deviation and the generative joint pathology. The absolute and relative indications for open reduction is given. The debate between supporters of open or closed reduction is still continuing and the issue has not been resolved. However, the final choice treatment modality should takes into account the location of the fracture, age of the patient, presence or absence of other associated injuries, cosmetic impact of the surgery and presence of other systemic medical conditions.
This presentation contains the detailed description about the courses, branches and supply of the Trigeminal Nerve, contains variations of maxillary nerve & Mandibular Nerve, and the detail about trigeminal Neurolgia and its managements
The trigeminal nerve is the largest cranial nerve with both motor and sensory components. It has three main divisions - ophthalmic, maxillary, and mandibular. The motor root originates in the pons and supplies muscles of mastication. The sensory root contains sensory fibers and divides into the three divisions. The ophthalmic nerve innervates the eye and parts of the face. The maxillary nerve innervates parts of the face, nasal cavity and palate. The mandibular nerve has motor fibers that innervate muscles of mastication and a large sensory component that provides sensation to parts of the face and oral cavity.
The document discusses the anatomy and branches of the mandibular nerve, including its course, distribution, and supply. It describes various anesthetic techniques for blocking branches of the mandibular nerve, including the inferior alveolar nerve block, lingual nerve block, buccal nerve block, and mental nerve block. It also discusses potential local complications from anesthetic techniques such as needle breakage, prolonged anesthesia, and soft tissue injury.
IS THE SCHNEIDERIAN MEMBRANE THICKNESS AFFECTED BY PERIODONTAL DISEASE? Shilpa Shiv
1) The study found that the thickness of the Schneiderian membrane, which lines the maxillary sinus, was significantly greater in patients with periodontally diseased maxillary molars compared to patients with edentulous areas.
2) While a smaller bone layer separating root tips from the sinus floor was associated with increased membrane thickness, no clear relationship was found between membrane thickness and clinical periodontal parameters.
3) The results indicate that cone-beam computed tomography can be useful for evaluating soft tissue conditions like Schneiderian membrane thickness in the maxillary sinus.
This presentation is done by Prof. Ahmed M. Adawy, Professor Emeritus, Dep. Oral & Maxillofacial Surg., Former Dean, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt.
The presentation is about the chapter of Temoromandibular Joint in Oral Surgery which includes definition, anatomy, diseases and its surgical treatment.
The mandible or lower jaw, is the largest & strongest bone of the face. The word “Mandible” is derived from Greek word
“mandere” – to masticate or chew. The Latin word “ mandibula” – lower jaw. It is horse-shoe shaped & the only movable bone of skull. Growth and development of an individual is divided into two periods Prenatal period and Post natal period. The first structure to develop in the primodium of the lower jaw is the mandibular division of trigeminal nerve that precedes the mesenchymal condensation forming the first [mandibular] arch. Endrocondral bone formation is seen in The condylar process, The coronoid process and The mental process. OUTER SURFACE OF MANDIBLE
1. External oblique line - origin to buccinator, depressor inferioris, depressor anguli oris.
2. Incisive fossa - origin of mentalis, mental slips of orbicularis oris.
3. Lateral surface of ramus - insertion for masseter.
4. Lower border - deep cervical fascia and platysma.
5. Postero-superior lateral surface of ramus - parotid gland.
6. Lateral surface of neck - attachment to lateral ligament of temperomandibular joint , parotid gland.
INNER SURFACE OF MANDIBLE
1. Mylohyoid line - origin to mylohyoid muscle , attachment to superior constrictor of pharynx, pterygomandibular raphae.
2. Medial surface of ramus - medial pterygoid muscle attachment.
Superior genial tubercles – genioglossus.
3. Inferior genial tubercles – origin to geniohyoid.
4. Lingula - sphenomandibular ligament.
5. Apex of coronoid process - temporalis attachment.
6. Pterygoid fovea - lateral pterygoid muscle.
7. Diagastric fossa - anterior belly of diagastric.
ARTERIAL SUPPLY OF MANDIBLE:
It is mainly divided into 2 categories :
1. Endosteal/ Central blood supply
2. Periosteal/ Peripheral blood supply
Central blood supply is via Inferior Alveolar Artery except the coronoid process which is supplied by Temporalis muscle vessels.
Inferior alveolar artery arises from maxillary artery which in turn is a branch of External carotid artery.
Inferior alveolar artery branches :
Lingual branch
Mylohyoid branch
Incisive branch
Mental branch
Peripheral blood supply is mainly via Periosteum via the nutrient vessels those penetrate the cortical bone and anastamose with the branches of Inferior alveolar artery.
VENOUS SUPPLY OF MANDIBLE
Drains into Internal Jugular vein and External Jugular vein through Maxillary vein, Facial vein and pterygoid plexus.
This document provides an overview of model analysis for mixed dentition. It defines study models and their objectives. Various types of model analyses are described, including those for mixed dentition like Moyer's analysis, which uses measurements of erupted mandibular incisors to estimate the sizes of unerupted canines and premolars. The goals and procedures of mixed dentition analysis are outlined, such as determining if there is enough space for permanent teeth. Factors considered include tooth sizes, arch perimeter, and expected changes during development.
Maxillofacial Surgery
Dental Students Fifth Year First semester
Lecture Name maxillofacial trauma part 2
Al Azhar University Gaza Palestine
Dr. Lama El Banna
The document discusses the anatomy of the mandible including the muscles of mastication, temporomandibular joint, nerve supply, and classifications of fractures. It examines the physical exam for mandibular fractures including assessing occlusion, trismus, and neurovascular status. Finally, it reviews treatment principles and options for mandibular fractures including maxillomandibular fixation, open reduction with rigid or non-rigid fixation, and external pin fixation.
This seminar explains about the development, relations, ligaments, various attachments, vascular and nervous supply and various surgical approaches and its modifications to TMJ
The document discusses growth and development of the maxilla from prenatal to postnatal periods. It describes how the maxilla develops from maxillary processes in the embryo. During prenatal growth, the maxilla is displaced downward and forward as the cranial base grows. Postnatally, the maxilla grows through bone deposition, remodeling at sutures, and expansion of the maxillary sinus. The primary palate develops early from the median palatine process, while the secondary palate forms from the palatine shelves fusing in the midline.
Growth and Development of Craniofacial Structure, Dentition and OcclusionHermie Culeen Flores
The document discusses growth and development of craniofacial structures, dentition, and occlusion. It covers:
- Mechanisms of bone growth including endochondral and intramembranous formation.
- Hypotheses of craniofacial growth including genetic and functional theories.
- Development of specific craniofacial regions like the cranial vault, basicranium, and nasomaxillary complex.
- Eruption sequences and development of the primary and permanent dentitions from prenatal to postnatal stages.
- Characteristics and phases of the mixed and permanent dentitions.
- Static and dynamic aspects of occlusion and types of occlusion like ideal, normal, and functional.
This document provides an overview of internal derangements of the temporomandibular joint (TMJ). It defines internal derangement as an abnormal relationship between the articular disc and condyle. The most common type is anterior disc displacement, which can be with or without reduction. Causes include trauma, functional overloading, joint laxity, and muscle spasms. Symptoms vary depending on the type but may include clicking, limited opening, and pain. Diagnosis involves clinical exams and MRI imaging. Treatment ranges from splint therapy to arthrocentesis or arthroscopy for lavage and relief of adhesions. Arthrocentesis is shown to improve opening and reduce pain by removing inflammatory factors from the
This document provides instructions for making final impressions for complete dentures, including custom tray fabrication, border molding techniques, and using selective pressure to record tissues in an undisplaced position. It describes areas that require special attention for the maxillary and mandibular impressions, such as the posterior palatal seal and retromylohyoid space. The goal is to make impressions that provide maximum coverage, close adaptation, and proper support and retention for the dentures.
The trigeminal nerve is the largest of the cranial nerves. It has both sensory and motor fibers. It has three main divisions - the ophthalmic, maxillary, and mandibular nerves. The ophthalmic nerve innervates parts of the face around the eyes. The maxillary nerve innervates parts of the face around the nose and mouth. The mandibular nerve is mixed and innervates muscles of mastication as well as parts of the face, tongue and mouth.
The maxillary nerve is the second division of the trigeminal nerve. It originates in the trigeminal ganglion and passes through the middle cranial fossa, pterygopalatine fossa, and orbit. In the pterygopalatine fossa, it gives off branches and connects to the pterygopalatine ganglion, the largest parasympathetic ganglion, which relays secretomotor fibers to glands of the nose, palate, and pharynx. The maxillary nerve and its branches provide sensory innervation to the face and motor input to the lacrimal gland.
Seminar on prenatal & postnatal development of maxillaDr . Arya S Kumar
This document discusses the prenatal and postnatal development of the maxilla. It begins by defining growth and development, and discussing the importance of understanding craniofacial growth. During the prenatal period, the maxilla develops from the maxillary process of the first branchial arch. Intramembranous ossification begins in the 8th week. The palatal shelves develop and later elevate into a horizontal position to fuse, forming the secondary palate. Postnatally, the maxilla continues growing through processes like cortical drift and growth at sutures. Understanding normal maxillary development is important for comprehending abnormalities.
This document discusses the muscles of mastication. It begins by defining mastication and describing the development of muscles from embryonic tissues. The primary muscles of mastication - masseter, temporalis, lateral pterygoid, and medial pterygoid - are then described in detail, including their origins, insertions, nerve/blood supply, and actions. Secondary muscles like the digastric, mylohyoid, and geniohyoid that assist in mastication are also outlined. The document concludes that the masticatory system requires precise muscle movement to effectively move the teeth during function.
The document discusses the muscles of mastication. There are 4 primary muscles - masseter, temporalis, lateral pterygoid, and medial pterygoid. These muscles develop from the first brachial arch and are innervated by the mandibular nerve. They work together to power the chewing cycle and move the mandible during opening, closing, and side-to-side motions. Secondary muscles like the digastric, mylohyoid, and geniohyoid can assist during difficult chewing. Conditions like tetanus and bruxism are also reviewed.
Muscles of mastication are the group of muscles that help in movement of the mandible as during chewing and speech. We need to study these muscles as they control the opening & closing the mouth & their role in the equilibrium created within the mouth. They also play a role in the configuration of face.
This document discusses the muscles of mastication. It begins by introducing the muscles and their anatomy. The primary muscles of mastication are the masseter, temporalis, medial pterygoid, and lateral pterygoid muscles. It describes the origin, insertion, nerve supply, blood supply, and actions of each muscle. Additionally, it covers related topics like the embryology of the muscles, clinical considerations like trismus and bruxism, and the significance of the muscles in orthodontics.
The document discusses the muscles of mastication - the muscles involved in chewing. It describes the anatomy, development, functions and clinical significance of the main muscles - the masseter, temporalis, lateral and medial pterygoid muscles. Conditions involving the muscles like myofascial pain dysfunction syndrome, trismus and benign masseteric hypertrophy are also covered. The muscles of mastication are important for prosthodontists to consider during treatments like impression making and recording jaw relations.
The document discusses the muscles of mastication including the masseter, temporalis, lateral pterygoid, and medial pterygoid muscles. It describes the masticatory system and its components, the functions of mastication in breaking down food, and the chewing cycle. It also discusses the neurological control of mastication and additional muscles involved like the digastric. The importance of understanding the masticatory system for dentists is described for areas like prosthodontics and its relevance to jaw movements. Some clinical significance of lesions impacting structures involved in mastication are also noted.
This document provides information about the muscles of mastication. It begins by introducing mastication as the process of chewing food and identifying the main muscles involved. The document then defines key terms like muscle and mastication. It proceeds to describe the four basic muscles of mastication - temporalis, masseter, medial pterygoid, and lateral pterygoid - covering their origins, insertions, actions, nerve and blood supply, palpation techniques, and clinical significance for each muscle. The document also discusses accessory muscles, development of the masticatory muscles, mandibular movements, and includes literature reviews on electromyographic studies related to muscle activity.
This slide is about mechanism of mastication. it include muscles of mastication. disorders .of masticatory muscles also included. mastication in different condition is also presented
As we know that the muscles play an important role in stability and support of a prosthesis,hence we should be well learned about their peripheries and actions.
Muscles of mastication
Introduction
Definitions
Development
Classification
Description of individual muscles
Muscles of facial expression
Introduction
Development
Classification
Description of individual muscles
Applied aspects
The document discusses the muscles of mastication. It begins by defining muscles and mastication. It then covers the development, classification, anatomy, actions, and clinical significance of the four primary muscles - temporalis, masseter, lateral pterygoid, and medial pterygoid. Secondary muscles like digastric, mylohyoid, and geniohyoid are also mentioned. Common muscle disorders like MPDS, trismus, and bruxism are summarized. Palpation techniques for muscles are provided along with their importance in dentistry.
The document discusses the muscles of mastication, which are responsible for chewing food. It describes the basic muscles - masseter, temporalis, medial pterygoid, and lateral pterygoid. It also discusses accessory muscles like the buccinator. Each muscle is described in detail, including its origin, insertion, nerve supply, blood supply, and actions. The document also discusses how the muscles are classified based on their functional roles in elevating or depressing the jaw. Examination techniques for the masseter and temporalis muscles are briefly covered at the end.
DEFINITION, ANATOMY, AND FUNCTIONS OF TEMPOROMANDIBULAR JOINT.
Joint between the head (condyle) of the mandible and the undersurface (articular fossa)of the squamous part of the temporal bone is the temporomandibular joint.
Type of joint : synovial joint (condylar variety).
Capable of providing-hinging (rotation) -gliding (translation) movement.
Sustains incredible forces of mastication.
articulating surfaces-articualar tubercle, mandibular fossa.
functions-Chewing
Sucking
Swallowing
Phonation
Facial expressions
Breathing Protrusion,
Retrusion,
Lateralization of the jaw
Opening the mouth
Maintain the correct pressure of the middle ear
Blood supply- Branches from superficial temporal and maxillary artery.
Veins follow the arteries.
Nerve supply-Auriculotemporal nerve (branch of mandibular nerve) and masseteric nerve (motar branch of anterior division of mandibular nerve).
movemnets of tmj- protraction, retraction, elevation, depression, side to side grinding.
examination of tmj- preauricular method and intraauricular method.
This document summarizes the muscles of mastication. It describes the four primary muscles - temporalis, masseter, lateral pterygoid, and medial pterygoid muscles. It discusses their embryology, blood supply, nerve innervation, actions, and clinical significance. A study found that around 26.8% of participants seeking dental care reported temporomandibular disorder pain. The muscles of mastication are important for chewing food and moving the jaw. Disorders can include pain, dysfunction, and infections or tumors in the mastication space.
Muscles of mastication deepak final copyDeepak Kakde
The document discusses the muscles of mastication. It describes the four primary muscles - masseter, temporalis, lateral pterygoid, and medial pterygoid. It details the origin, insertion, nerve supply and actions of each muscle. It also discusses the secondary muscles that assist in mastication, including the digastric, mylohyoid and geniohyoid muscles. Finally, it covers some clinical considerations regarding diseases and disorders that can affect the muscles of mastication.
The mandible is the largest and strongest bone of the face. It develops from the first pharyngeal arch and consists of a body with alveolar, inferior and mylohyoid borders, and a ramus with coronoid and condylar processes. The mandible undergoes both prenatal and postnatal growth, with the condyle showing considerable activity as the mandible grows downward and forward. Key parts include the body, ramus, coronoid process, and condylar process. The mandible articulates with the temporal bone at the temporomandibular joint.
The mandible is the largest and strongest bone of the face. It develops from the first pharyngeal arch and consists of a body and bilateral rami. The body forms the lower jaw and contains the tooth sockets on its superior border. Each ramus has multiple surfaces and borders including the coronoid and condylar processes. Important anatomical landmarks include the mental foramen, mandibular canal, and angle of the mandible. The facial artery and branches of the trigeminal nerve course close to the mandible and must be protected during surgeries in this region.
This document provides an overview of the anatomy and physiology of the temporomandibular joint (TMJ). It describes the development, components, ligaments, vascularization, innervation and relationships of the TMJ. The key components discussed include the articular disc, condyle, articular eminence, glenoid fossa, capsule and ligaments. The functions of synovial fluid in lubrication and the receptors and nerves involved in proprioception are also summarized.
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Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. Chapter 3, Cardiology Explained, https://www.ncbi.nlm.nih.gov/books/NBK2214/
7. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
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4. CONTENTS:
1. Introduction
2. Definition
3. Development
4. Classification
5. Movements of mandible
6. Muscles of mastication
7. Masticatory muscle disorders
8. Conclusion
9. Reference
4
5. INTRODUCTION:
Masticatory system is a complex, highly refined, functional unit,
regulated and coordinated by a neurological control system, which
involves nerves and muscles.
Muscles of mastication are the group of muscles that helps in
movement of the mandible as during chewing and speech. They also
play a role in the configuration of face
Four pairs of the muscles in the mandible makes the chewing
movement possible. These muscle along with accessory ones together
are termed as “MUSCLES OF MASTICATION”.
5
6. DEFINITION:
MUSCLE: a tissue composed of contractile cells or fibers that effect
movement of an organ or part of the body.
MASTICATORY MUSCLE: any of the muscles that elevates the mandible to
close the mouth (temporalis muscle, superficial and deep masseter muscle,
medial pterygoid muscle)
6
7. 7
MASTICATION: the process of chewing food for swallowing
and digestion.
MASTICATORY SYSTEM: the organs and structures primarily
functioning in mastication, these includes the teeth with their
supporting structures, craniomandibular articulations, mandible,
positioning and accessory musculature, tongue, lips, cheek, oral
mucosa, and the associated neurologic complex.
8. DEVELOPMENT:
The basic muscles of mastication develops from the mesoderm of the first
pharyngeal arch.
The muscular tissue develops from embryonic cells called myoblast.
Muscular components of branchial arch form many striated muscles in the head and
neck region.
Muscles of mastication are derived from the first branchial arch that is the
MANDIBULAR ARCH, which is innervated by the mandibular branch of
trigeminal nerve.
8
9. 9
Development of maxilla:
Maxilla forms within the maxillary prominences extending ventrally from
the dorsal aspect of a much larger mandibular swelling. Ossification of
maxilla begins slightly later than in the mandible.
The primary ossification center appears for each maxilla in the 7th week.
The secondary centers are at the zygomatic, nasopalatine and orbitonasal
areas.
Maxilla forms within the maxillary prominences extending vertically from
the dorsal aspect of a much larger mandibular swelling.
10. The primary ossification centre appears for each maxilla in the 7th week. The
secondary centres are at the zygomatic, nasopalatine and orbitonasal areas.
Of lies in the angle formed by the infraorbital nerve and anterior superior alveolar
nerve, above the part of the dental lamina from which the canine tooth germ develops.
The premaxilla begins to ossify from the two centres in the latter part of the 7th week.
Postnatal growth of maxilla occurs by:
Apposition of the bone
surface remodelling.
10
11. Development of Mandible:
Development of mandible starts at the 2nd week of intrauterine life. 36 –
38th day, mandibular ectomesenchyme interacts with the mandibular
epithelium before primary ossification.
First ossification centre for each half arises in the 6th week in region of
bifurcation of Inferior Alveolar Nerve into Mental, the ossification
spreads dorsally and ventrally to form ramus and body.
Ossification stops at site where it would be lingual.
Medially it meets its fellow counterpart, distally up to middle ear.
Secondary accessory cartilages occurs between 10th – 14th weeks to form
head of condyle, coronoid, mental protuberances.
11
12. Coronoid cartilage fuses with expanding intramembranous ramus before birth. Condylar cartilage
appears at 10th week.
This is primordium for future condyle. Cartilage differentiate by interstitial n appositional growth.
By the 14th week, 1st evidence of endochondral bone formation is seen.
Condylar cartilage is an important growth centre for ramus. Condylar growth at its peak at puberty.
Occurs 12-14 months’ post natally,2 halves fuse into synostosis.
Mandible appears as a single bone. Basal bone forms one unit to which alveolar, condylar, coronoid,
angular process and chin is attached.
They grow by functional matrix theory. Teeth acts as functional matrix for the development of alveolar
bone. Temporalis influences coronoid process. Masseter and medial pterygoid at angle and lateral
pterygoid at the condyles.
12
13. Post-natal growth of mandible:
Growth of width of mandible is completed first, then growth in length and finally growth in
height.
Growth in width is completed before adolescent growth spurts. Growth in length continues
through puberty.
Main sites of post-natal growth in the mandible are:
- Condylar cartilage
- Posterior border of the rami
- Alveolar ridges
13
14. CLASSIFICATION:
Primary muscles:
a. Temporal
b. Masseter
c. Medial pterygoid
d. Lateral pterygoid - superior & inferior
Accessory muscles:
a. Mylohyoid
b. Geniohyoid
c. Anterior belly of digastric
14
15. 15
Based on functional movements:
Jaw elevators Jaw depressors
- Masseter - Lateral pterygoid
- Temporalis - Anterior belly of digastric
- Medial pterygoid - Geniohyoid
- Mylohyoid
16. MANDIBULAR MOVEMENTS:
1. Depression : As in opening of mouth.
2. Elevation : As in closing of mouth.
3. Protrusion : Horizontal movement of the mandible anteriorly.
4. Retraction : Horizontal movement of mandible posteriorly.
5. Rotation : The anterior tip of the mandible is slewed from side to side.
16
18. Origin:
Lateral surface of the skull
Insertion:
Coronoid process and anterior border of
ramus of mandible
18
19. 19
Innervations:
Temporal nerve (branch of mandibular nerve).
Blood supply:
Middle and Deep temporal arteries (branches of superficial temporal
& maxillary artery).
Functions:
Elevates and retracts jaw.
Assists in rotation.
Active in clenching.
20. Palpation:
Patient is asked to clench the teeth
a. Anterior region is palpated above
the zygomatic arch and anterior to
the TMJ.
b. Middle region is palpated above the
TMJ and superior to zygomatic
arch.
c. Posterior region is palpated above
and behind the ear.
20
21. 21
Clinical significance:
Recording coronoid process area.
The patient is instructed to close and move his mandible from side to
side and then immediately asked to wide open.
The side to side motion records the activity of the coronoid process in
a closed position whereas opening causes the coronoid to sweep past
the denture periphery.
22. 2. MASSETER
It is quadrilateral in shape & covers the
lateral surface of ramus of mandible.
The origin of the whole muscle is from
the zygomatic process & consists of three
layers i.e. superficial, middle and the
deep layer.
22
24. Blood supply:
Masseteric artery(branch of maxillary artery)
Functions:
Elevates and protracts jaw.
Assist in lateral movement.
Active in clenching.
24
25. 25
Palpation:
The patient is asked to clench their teeth
and using both hands, the practitioner
palpates the masseter muscle on both
sides extra orally, making sure that the
patient continues to clench during the
procedure.
Palpate the origin of the masseter
bilaterally along the zygomatic arch and
continue to palpate down the body of the
mandible where the masseter is attached.
26. 26Clinical significance:
An active masseter muscle will create a concavity in the outline of the
distobuccal border and a less active muscle may result in a convex border.
In this area the buccal flange must converge medially to avoid displacement
due to contraction of the masseter muscle because the muscle fibres in that
area are vertical and oblique.
Effects of masseter muscle on the distobuccal border
a. Moderate activity will create a straight line.
b. An active muscle will create a concavity.
c. An inactive muscle will create a convexity.
27. 27
Activation of masseteric notch and distal areas:
Instruct the patient to open their mouth widely and then to close against
the resting forces of your finger.
28. 28
Opening wide activates the muscles of pterygomandibular raphe by
stretching, which thereby defines the most distal extension.
Instructing the patient to close against your fingers on the tray handle
causes masseter muscle to contract and push against the medially situated
buccinators muscle.
Masseter hypertonicity is found in patients who have premature contacts
on the networking side.
29. 3. MEDIAL PTERYGOID:
It is also called Pterygoideus internus or internal pterygoid muscle.
Quadrilateral in shape. Consists of two heads: superficial & deep.
29
30. Origin:
Pterygoid fossa and medial surface of lateral
pterygoid plate.
Insertion:
Medial surface of angle of mandible.
Innervation:
Medial pterygoid nerve (division of trigeminal
nerve).
30
31. Blood supply:
Branch of maxillary artery.
Functions:
Elevates jaw
Causes lateral movement and protrusion.
The lateral and medial pterygoid on one side protrude the mandible to the
opposite side.
Lateral and medial pterygoid on both side acting together to produce side
to side movement.
31
32. 32Palpation:
It can be palpated by placing the finger on the lateral aspect of the
pharyngeal wall of the throat, this palpation is difficult and sometimes
uncomfortable for the patient.
33. 33
Functional manipulation is done when the muscle becomes fatigued
and symptomatic.
The muscle contracts as the teeth are coming in contact.
They also stretches when the mouth is wide open.
34. 34Clinical significance:
Mandibular dysfunction:
The medial pterygoid muscle is not usually involved in gnathic
dysfunction but when they are hypertonic, the patient is usually conscious
of a feeling of fullness in the throat and an occasional pain on swallowing.
36. 4. SUPERIOR LATERAL PTERYGOID
Origin:
Infratemporal surface of greater wing of sphenoid.
Insertion:
Articular capsule and disk, neck of condyle.
Innervation:
Branch of masseteric or buccal nerve.
Blood supply:
Branch of maxillary artery.
Functions:
Positions disk in closing
36
37. 5. INFERIOR LATERAL PTERYGOID:
Origin:
Lateral surface of lateral pterygoid plate.
Insertion:
Neck of condyle.
Innervation:
Branch of masseteric nerve or buccal nerve.
Blood supply:
Branch of maxillary artery.
Function:
Protrudes and depresses jaw
Causes lateral movements
37
38. Palpation:
The little finger is inserted facial to the maxillary teeth and around distal to
the pterygomaxillary or hamular notch to palpate the lateral pterygoid
38
39. 39Clinical significance:
Unilateral failure of lateral pterygoid muscle to contract results in
deviation of the mandible towards the affected side on opening.
Bilateral failure results in limited opening, loss of protrusion and loss
of full lateral deviation.
The insertion of the lateral pterygoid in the articular disc occurs in the
medial aspect of the anterior border of the disc and thus it plays a role
in the TMJ diseases especially in internal derangement.
40. 5. MYLOHYOID:
Origin:
Inner surface of mandible.
Insertion:
Hyoid and mylohyoid raphe.
Innervation:
Branches of mylohyoid nerve (division of trigeminal nerve).
Blood supply:
Submental artery.
40
41. Functions:
Elevates and stabilizes hyoid bone.
Clinical significance:
On denture borders: Mylohyoid area
Instruct the patient to place the tip of his/her tongue into the upper and
lower vestibules on the right and left sides.
The area to be moulded is reheated and the patient is instructed to swallow
two or three times in rapid succession.
The tongue movements raises the floor of the mouth through contraction
of the mylohyoid muscle.
41
42. 6. GENIOHYOID
Origin:
Genial tubercle.
Insertion:
Hyoid bone.
Innervation:
First cervical via Hypoglossal nerve
Blood supply:
Branch of lingual artery.
Functions:
Elevates and draws hyoid forwards.
42
43. Clinical significance:
For mandibular impressions:
On recording labial flange and labial frenum. The lip is massaged from side
to side to mold the compound to desired functional extension. In order to
activate the mentalis muscle the patient is asked to lick his lower lip.
For maxillary impressions in labial flange and labial frenum areas:
Manually, mold the compound by externally moving the lip side to side,
simultaneously applying finger pressure to control the width of the border.
Lift the upper lip and vertically place the frenum into the softened
compound and mold with your fingers using side to side external motion.
43
44. 7. ANTERIOR BELLY OF DIGASTRIC:
Origin:
Tendons linked to hyoid by fascia.
Insertion:
Digastric fossa (lower border of mandible).
Innervation:
Branch of mylohyoid nerve (division of trigeminal).
Blood supply:
Branch of facial artery.
Functions:
Elevates hyoid & depresses jaw.
44
45. 45Gnathology:
The study of biology of masticatory mechanisms and the kinematic recording
of the mandibular positions. (GPT 9)
Aims and objectives of Gnathology
1.Optimum oral health
2.Anatomic harmony
3.Functional harmony
4.Occlusal stability
46. 46
Gnathology deals with the whole apparatus of mastication.
According to Stallard “it was proposed as the science that would
concentrate on the gnathic system – Gnathology- to emphasis how
important the knowledge of gnathodynamics is in caring for teeth”.
When studies in Gnathology were instituted, it was accepted that balanced
occlusion was the answer to occlusal problems.
Gysi suggested the research tool that McCollum used in 1920 to locate the
opening and closing axis position and to transfer a patients
maxillomandibular relations to an articulator.
47. 47 For his research McCollum fastened the snow face bow rigidity to the
lower teeth and located the axis position.
When he had done this, he discovered other facts.
i. When the patient closed on a hard object anterior or posterior teeth, the
point of stylus did not change position.
ii. Translation on the horizontal axis made constant paths.
iii. The axis remained constant to the mandibular teeth when the jaws were in
protrusion during opening and closing of the jaw if the openings were not
excessive.
iv. The coincidence of repeated terminal hinge positions was so regular that
it indicated that the terminal hinge axis position is constant.
48. 48 In 1920’s McCollum learned how to test the accuracy of an articulator and
in 1927 he undertook to test for balanced occlusion.
It took almost 20 years for Stuart to conclude that balanced occlusion is not
suitable for natural teeth and probably not suitable for dentures.
Stuart designed his first articulator in 1928-29 but decided not to promote it
out of deference to McCollum.
The jaw writings are recorded using pantograph, a mechanical device for
reproducing a map and drawing on the same or different scale.
49. 49
The jaw writings are recorded using pantograph, a mechanical device for
reproducing a map and drawing on the same or different scale.
The purpose of the mandibular recorder(pantograph) is to locate the centers
of mandibular movements and at the same time record the path of motion that
these centers take in relaxation to a given plane in the face.
The axis- orbital plane is the one most often used.
54. 54MASTICATORY MUSCLE DISORDERS :
Functional disorders of mastication are generally known as masticatory
muscle disorders
The major symptoms are pain and dysfunction.
PAIN:
Pain felt in muscle is known as MYALGIA.
Symptoms are associated with feeling of muscle fatigue and tightness.
Severity of the pain is related to functional activity of the muscle involved.
55. 55DYSFUNCTION:
Seen as decrease in the range of mandibular movements.
When muscle is compromised by overuse, stretching or contraction
causes increased pain.
Acute malocclusion is also a type of dysfunction.
Sudden change in the resting length of muscle causes an acute
malocclusion.
Treatment should never be directed towards correcting the occlusion
rather it should be aimed at eliminating the muscle disorder.
56. 56Masticatory muscle disorder:
i. Myospasm
ii. Myofascial pain
iii. Centrally mediated myositis
iv. Myofascial pain dysfunction syndrome
v. Trismus
vi. Bruxism
57. 57
MYOSPASM:
Involuntary CNS induced tonic muscle contraction often associated with
local metabolic conditions within the muscle tissues.
Usually short lived.
When spasm occurs repeatedly, the condition is known as dystonia.
Treatment:
Etiology of the myospam should be addressed to prevent recurrent
myospasm.
Pain reduction by vapocoolant spray, ice or even injection of local
anaesthetic into the muscle.
Once pain is reduced muscle conditioning exercises can be performed.
58. 58
MYOFACIAL PAIN:
Also known as trigger point myalgia.
Characterized by local areas of firm, hypersensitive bands of muscle tissue
known as trigger points.
Unique feature of the trigger point is that it can produce constant deep pain.
Most common effects is reffered pain described as tension type of headache.
Pain increases with function.
Treatment:
Eliminate the source of ongoing pain
Pressure and massage.
Injection and stretch
59. 59
CENTRALLY MEDIATED MYOSITIS:
Also known as chronic myositis.
Chronic, continuous muscle pain disorder originating predominantly from
CNS effects that are felt peripherally in muscle tissue.
Characterized by muscle tightness, pain at rest, pain on palpation, structural
dysfunction.
Treatment:
Supportive: soft diet, stabilization appliance, application of moist heat or
cold.
Definitive: treat the underlying cause.
Emotional stress therapy, occlusal therapy in musculoskeletal stable position.
60. 60MYOFACIAL PAIN DYSFUNCTION SYNDROME:
Most common type of TMJ pain associated with masticatory muscles.
Etiology:
High stress level.
Poor habits including bruxism.
Poor dentition.
Treatment:
Involves 4 phases of therapy which includes muscle exercises and drugs
involving NSAIDs and muscle relaxants.
A bite appliance is worn by the patient in the further stages to splint the
muscle movements.
61. 61TRISMUS:
Trismus is defined as a prolonged tetanic spasm of the jaw muscle by
which the normal opening of the mouth is restricted.
Restricted jaw movements regardless to the etiology.
Treatment:
Removal of the etiology.
Heat therapy.
Warm saline rinses.
NSAIDS.
Passive muscle stretching exercise
62. CONCLUSION:
The masticatory system is extremely complex, primarily made of bones, muscles,
ligaments and teeth.
Precise movement of mandible by the musculature is required to move the teeth
effectively across each other during function.
The knowledge of the anatomy physiology and mechanism of these ,usc;es are basic to
understand the movements.
62
63. REFERENCES:
Contemporary fixed prosthodontics - Rosenstiel
Human anatomy by B. D. Chaurasia (3rd edition).
Complete denture prosthodontics by John. J. Sharry.
Syllabus of complete denture – Charles M Heartwell
63