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.
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.
This seminar explains about the development, relations, ligaments, various attachments, vascular and nervous supply and various surgical approaches and its modifications to TMJ
Pediatric facial injuries can occur through various means like falls, motor vehicle accidents, abuse, and sports. Facial fractures are more common after age 5 while soft tissue injuries may require special care due to difficulties obtaining child cooperation and potential effects on growth. Examination involves inspection of injuries and palpation of bone surfaces to identify fractures, with radiologic imaging like CT used to further evaluate injuries. Treatment depends on the type of injury but may include cleaning wounds, repairing soft tissue lacerations, setting facial bones, and stabilizing dental injuries. Close monitoring is needed for developmental effects.
This document provides an overview of Lefort I osteotomy, including:
- A brief history describing the development of maxillary osteotomy techniques.
- Anatomical considerations and the biologic basis for maxillary osteotomies, which have shown adequate blood supply can be maintained.
- Indications for Lefort I osteotomy include altering vertical dimension, anteroposterior movements, and surgical expansion of the maxilla.
- Types of Lefort I osteotomies are described, including classic, quadrangular, and segmental variations. Postoperative management and potential complications are also outlined.
This document discusses the temporomandibular joint (TMJ), including its anatomy, common disorders like ankylosis, diagnostic methods, and surgical treatment options. Ankylosis is a fusion of the joint that restricts movement, often caused by trauma, infection, or arthritis. Surgical treatments aim to release the ankylosed mass and create a functional joint, preventing recurrence. Common procedures include condylectomy, gap arthroplasty, and interpositional arthroplasty using grafts or implants to maintain joint structure. The goal is restoring form and function through reestablishing mobility.
This document discusses the history and types of flaps used in reconstructive surgery. It begins by defining a flap as a unit of tissue transferred from a donor site to a recipient site while maintaining its own blood supply. It then discusses the origins of flaps dating back to 600 BC and highlights some important developments over time, including the first use of forehead and cheek flaps for nasal reconstruction. The document outlines different ways flaps can be classified, such as by blood supply, location, tissue content, configuration, and transfer method. Specific flap types are defined, such as advancement, rotational, and interpolated flaps. Key considerations for flap design like tension lines and esthetic zones are also reviewed.
Detailed discussion on diagnosis and management of TMJ ankylosis. Surgical anatomy and applied aspects of TMJ is discussed. Reconstruction of ramus-condyle unit is also discussed. Compications of TMJ surgery are also discussed
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.
This seminar explains about the development, relations, ligaments, various attachments, vascular and nervous supply and various surgical approaches and its modifications to TMJ
Pediatric facial injuries can occur through various means like falls, motor vehicle accidents, abuse, and sports. Facial fractures are more common after age 5 while soft tissue injuries may require special care due to difficulties obtaining child cooperation and potential effects on growth. Examination involves inspection of injuries and palpation of bone surfaces to identify fractures, with radiologic imaging like CT used to further evaluate injuries. Treatment depends on the type of injury but may include cleaning wounds, repairing soft tissue lacerations, setting facial bones, and stabilizing dental injuries. Close monitoring is needed for developmental effects.
This document provides an overview of Lefort I osteotomy, including:
- A brief history describing the development of maxillary osteotomy techniques.
- Anatomical considerations and the biologic basis for maxillary osteotomies, which have shown adequate blood supply can be maintained.
- Indications for Lefort I osteotomy include altering vertical dimension, anteroposterior movements, and surgical expansion of the maxilla.
- Types of Lefort I osteotomies are described, including classic, quadrangular, and segmental variations. Postoperative management and potential complications are also outlined.
This document discusses the temporomandibular joint (TMJ), including its anatomy, common disorders like ankylosis, diagnostic methods, and surgical treatment options. Ankylosis is a fusion of the joint that restricts movement, often caused by trauma, infection, or arthritis. Surgical treatments aim to release the ankylosed mass and create a functional joint, preventing recurrence. Common procedures include condylectomy, gap arthroplasty, and interpositional arthroplasty using grafts or implants to maintain joint structure. The goal is restoring form and function through reestablishing mobility.
This document discusses the history and types of flaps used in reconstructive surgery. It begins by defining a flap as a unit of tissue transferred from a donor site to a recipient site while maintaining its own blood supply. It then discusses the origins of flaps dating back to 600 BC and highlights some important developments over time, including the first use of forehead and cheek flaps for nasal reconstruction. The document outlines different ways flaps can be classified, such as by blood supply, location, tissue content, configuration, and transfer method. Specific flap types are defined, such as advancement, rotational, and interpolated flaps. Key considerations for flap design like tension lines and esthetic zones are also reviewed.
Detailed discussion on diagnosis and management of TMJ ankylosis. Surgical anatomy and applied aspects of TMJ is discussed. Reconstruction of ramus-condyle unit is also discussed. Compications of TMJ surgery are also discussed
This document provides an overview of secondary alveolar bone grafting for cleft lip and palate patients. It discusses the goals and optimal timing of the procedure, how patients are evaluated, and details regarding graft source options including iliac crest, tibia, rib, and cranial bone. It also covers pre-surgical orthodontics and preparation of the cleft alveolus, as well as post-operative care considerations.
This document provides an overview of the mandible, including its development, anatomy, age-related changes, and clinical applications. It discusses how the mandible develops from the first pharyngeal arch and ossifies through both intramembranous and endochondral bone formation. The anatomy of the mandible is described in detail, including its various parts and structures. Age-related changes to the mandible from birth through adulthood and old age are also reviewed. Finally, the document discusses some applied clinical aspects of the mandible relating to dislocations, fractures, and considerations for surgery.
This document discusses various methods of assessing difficulty for removal of impacted mandibular third molars based on panoramic radiographs. It describes several classification systems:
- Winter's classification which evaluates angulation.
- Assessment of height of the mandible, angulation of the second molar, root shape and development, follicle size, and path of tooth exit. Scores are assigned in each category.
- WHARFE assessment combines the features assessed above into a single score to determine overall difficulty.
However, the document notes that radiographs only provide limited information and may not capture the full range of variations encountered. The actual difficulty during surgery may differ from radiographic assessments. Surgeons should not
The document discusses various surgical approaches for the facial skeleton, including extraoral and intraoral incisions. It covers key principles for placing incisions such as following natural lines and avoiding vital structures. Specific approaches are described for the mandible, condyle, orbit, maxilla, and nasal skeleton. Factors to consider for any facial incision include scar visibility, underlying anatomy, and adequate surgical access. Both open and endoscopic techniques are presented.
This document provides an overview of surgical approaches to the temporomandibular joint (TMJ). It discusses several extraoral and intraoral approaches, including the preauricular, endaural, postauricular, coronal, retromandibular, and intraoral vestibular approaches. For each approach, it highlights considerations for exposure and visibility of the joint, avoidance of neurovascular structures, and postoperative aesthetics. Complications are also briefly mentioned. Detailed anatomical descriptions and illustrations are provided to demonstrate the surgical planning and exposure for different approaches.
The orbit is a pyramid-shaped cavity located in the skull that houses the eye and surrounding structures. It is formed by seven bones and contains the eyeball, extraocular muscles, blood vessels, nerves and other tissues. The orbit communicates with surrounding areas through several openings that transmit nerves and vessels between the orbit and other craniofacial regions. The complex anatomy of the orbit allows for movement of the eye while protecting its delicate contents.
The free fibula flap technique involves harvesting a skin paddle and segment of the fibula bone based on a vascular pedicle from the peroneal artery. Key steps include:
1. Identifying perforators from the peroneal artery to the skin and outlining a skin paddle.
2. Elevating muscles from the fibula bone and performing osteotomies to harvest the fibula segment.
3. Dissecting the peroneal artery and its branches to isolate the vascular pedicle.
4. Verifying adequate blood flow to the foot before transecting the pedicle to the desired length.
This document provides an overview of reconstruction flaps in oral and maxillofacial surgery. It begins with an introduction discussing the challenges of reconstructing maxillofacial defects. The history of flap surgery is then reviewed from 600 BC to modern developments. Flaps are defined as tissues containing a blood vessel network to support survival when transferred. The document outlines classifications of flaps by movement, blood supply, composition, and other characteristics. Specific local and regional flap types are described in detail, including forehead, submental island, and pectoralis major flaps. Factors in planning reconstruction with flaps and evaluating defects are also discussed.
The document discusses naso-orbito-ethmoidal (NOE) fractures, which involve the central upper midface region. It describes the anatomy and classification of NOE fractures. Markowitz classification system categorizes NOE fractures into 5 types based on the status of the central bony fragment and involvement of the medial canthal tendon. Type I and II fractures involve a single or displaced central fragment with an intact tendon. Type III fractures have comminution beneath the tendon. Imaging such as CT is important for diagnosis.
This document discusses mandibular condylar fractures, including:
1. It provides an overview of the etiology, classification, clinical features, diagnosis, and management of mandibular condylar fractures.
2. Treatment protocols for geriatric and pediatric patients are also discussed.
3. The indications and contraindications of closed and open reduction and fixation techniques for condylar fractures are analyzed in detail.
The document discusses the functional anatomy of the mandible. It covers the embryology and development of the mandible from Meckel's cartilage, including ossification centers and growth of the condylar and ramus regions. The anatomical structures of the mandible are described, including the body, ramus, condylar and coronoid processes. The related muscles, trajectories of force, biomechanics of movement, and applied anatomy are summarized. Abnormalities including fractures, infections, tumors and developmental variations are also covered.
The maxillary sinus is the largest of the paranasal sinuses. It develops within the body of the maxilla and communicates with the nasal cavity via the ostium in the middle meatus. The maxillary sinus has important anatomical relationships with surrounding structures like the orbit, teeth roots, and nerves. Diagnostic evaluation of the maxillary sinus involves medical history, clinical examination including transillumination, and imaging modalities like radiography, CT, MRI, ultrasound, and endoscopy.
This document describes the technique for harvesting a costochondral graft from the rib cage. Key steps include: 1) Marking and prepping the anterior chest wall, 2) Making a 6-8 cm incision over the rib, 3) Developing a tissue plane between the rib periosteum and pleura, 4) Osteotomizing the lateral and medial portions of the rib to harvest the graft with a cartilage cap, 5) Inspecting for pleural tears and closing layers. Costochondral grafts are useful for reconstructing craniofacial and TMJ defects due to their growth potential in children and biocompatibility. Complications can include pneumothorax, fracture, and scar formation
The document discusses reconstruction of the temporomandibular joint (TMJ) through various methods including autogenous grafts, alloplastic devices, distraction osteogenesis, and tissue engineering. Autogenous grafts that can be used include costochondral grafts, iliac crest grafts, fibular grafts, and coronoid process grafts, each with advantages and limitations. Alloplastic devices made of various materials are also discussed, including the Kent-Vitek prosthesis, Christensen's prosthesis, and TMJ Concepts prostheses. Distraction osteogenesis is described as a method to reconstruct the mandibular ramus through gradual distraction. Tissue engineering is mentioned as a potential future approach involving scaffolds
Journal club on Mandibular fracture after third molarDr Bhavik Miyani
1) The document summarizes a journal club presentation on a study analyzing factors leading to mandibular fractures after third molar removal.
2) Six patients who experienced mandibular fractures on average 14 days after third molar surgery were examined. All patients were fully dentulous and between 42-50 years old.
3) The study found that advanced age combined with a full dentition were major risk factors for this complication. Pre-existing bone lesions from cysts or other issues also increased the risk of fracture by weakening the mandible.
The document provides an overview of the surgical anatomy of the mandible. It discusses the parts and features of the mandible, including the body, rami, coronoid and condylar processes. It details the growth and development of the mandible from the prenatal period through adulthood. Key anatomical structures are described, such as ligaments, muscles, nerves, blood vessels and lymph nodes associated with the mandible. Clinical considerations for surgical procedures involving the mandible are also mentioned.
The document discusses prenatal and postnatal growth of the mandible. It describes how the mandible develops from mesenchymal condensations in the pharyngeal arches during prenatal development. It forms through both intramembranous and endochondral ossification. The condyle, coronoid process, and mental region develop through endochondral ossification of cartilage models. Postnatally, the mandible grows downward and forward through appositional bone growth at the condyle, ramus, and alveolar processes to accommodate the permanent dentition. The chin develops through periosteal bone apposition on the lingual surface in males during late growth.
This document provides an overview of secondary alveolar bone grafting for cleft lip and palate patients. It discusses the goals and optimal timing of the procedure, how patients are evaluated, and details regarding graft source options including iliac crest, tibia, rib, and cranial bone. It also covers pre-surgical orthodontics and preparation of the cleft alveolus, as well as post-operative care considerations.
This document provides an overview of the mandible, including its development, anatomy, age-related changes, and clinical applications. It discusses how the mandible develops from the first pharyngeal arch and ossifies through both intramembranous and endochondral bone formation. The anatomy of the mandible is described in detail, including its various parts and structures. Age-related changes to the mandible from birth through adulthood and old age are also reviewed. Finally, the document discusses some applied clinical aspects of the mandible relating to dislocations, fractures, and considerations for surgery.
This document discusses various methods of assessing difficulty for removal of impacted mandibular third molars based on panoramic radiographs. It describes several classification systems:
- Winter's classification which evaluates angulation.
- Assessment of height of the mandible, angulation of the second molar, root shape and development, follicle size, and path of tooth exit. Scores are assigned in each category.
- WHARFE assessment combines the features assessed above into a single score to determine overall difficulty.
However, the document notes that radiographs only provide limited information and may not capture the full range of variations encountered. The actual difficulty during surgery may differ from radiographic assessments. Surgeons should not
The document discusses various surgical approaches for the facial skeleton, including extraoral and intraoral incisions. It covers key principles for placing incisions such as following natural lines and avoiding vital structures. Specific approaches are described for the mandible, condyle, orbit, maxilla, and nasal skeleton. Factors to consider for any facial incision include scar visibility, underlying anatomy, and adequate surgical access. Both open and endoscopic techniques are presented.
This document provides an overview of surgical approaches to the temporomandibular joint (TMJ). It discusses several extraoral and intraoral approaches, including the preauricular, endaural, postauricular, coronal, retromandibular, and intraoral vestibular approaches. For each approach, it highlights considerations for exposure and visibility of the joint, avoidance of neurovascular structures, and postoperative aesthetics. Complications are also briefly mentioned. Detailed anatomical descriptions and illustrations are provided to demonstrate the surgical planning and exposure for different approaches.
The orbit is a pyramid-shaped cavity located in the skull that houses the eye and surrounding structures. It is formed by seven bones and contains the eyeball, extraocular muscles, blood vessels, nerves and other tissues. The orbit communicates with surrounding areas through several openings that transmit nerves and vessels between the orbit and other craniofacial regions. The complex anatomy of the orbit allows for movement of the eye while protecting its delicate contents.
The free fibula flap technique involves harvesting a skin paddle and segment of the fibula bone based on a vascular pedicle from the peroneal artery. Key steps include:
1. Identifying perforators from the peroneal artery to the skin and outlining a skin paddle.
2. Elevating muscles from the fibula bone and performing osteotomies to harvest the fibula segment.
3. Dissecting the peroneal artery and its branches to isolate the vascular pedicle.
4. Verifying adequate blood flow to the foot before transecting the pedicle to the desired length.
This document provides an overview of reconstruction flaps in oral and maxillofacial surgery. It begins with an introduction discussing the challenges of reconstructing maxillofacial defects. The history of flap surgery is then reviewed from 600 BC to modern developments. Flaps are defined as tissues containing a blood vessel network to support survival when transferred. The document outlines classifications of flaps by movement, blood supply, composition, and other characteristics. Specific local and regional flap types are described in detail, including forehead, submental island, and pectoralis major flaps. Factors in planning reconstruction with flaps and evaluating defects are also discussed.
The document discusses naso-orbito-ethmoidal (NOE) fractures, which involve the central upper midface region. It describes the anatomy and classification of NOE fractures. Markowitz classification system categorizes NOE fractures into 5 types based on the status of the central bony fragment and involvement of the medial canthal tendon. Type I and II fractures involve a single or displaced central fragment with an intact tendon. Type III fractures have comminution beneath the tendon. Imaging such as CT is important for diagnosis.
This document discusses mandibular condylar fractures, including:
1. It provides an overview of the etiology, classification, clinical features, diagnosis, and management of mandibular condylar fractures.
2. Treatment protocols for geriatric and pediatric patients are also discussed.
3. The indications and contraindications of closed and open reduction and fixation techniques for condylar fractures are analyzed in detail.
The document discusses the functional anatomy of the mandible. It covers the embryology and development of the mandible from Meckel's cartilage, including ossification centers and growth of the condylar and ramus regions. The anatomical structures of the mandible are described, including the body, ramus, condylar and coronoid processes. The related muscles, trajectories of force, biomechanics of movement, and applied anatomy are summarized. Abnormalities including fractures, infections, tumors and developmental variations are also covered.
The maxillary sinus is the largest of the paranasal sinuses. It develops within the body of the maxilla and communicates with the nasal cavity via the ostium in the middle meatus. The maxillary sinus has important anatomical relationships with surrounding structures like the orbit, teeth roots, and nerves. Diagnostic evaluation of the maxillary sinus involves medical history, clinical examination including transillumination, and imaging modalities like radiography, CT, MRI, ultrasound, and endoscopy.
This document describes the technique for harvesting a costochondral graft from the rib cage. Key steps include: 1) Marking and prepping the anterior chest wall, 2) Making a 6-8 cm incision over the rib, 3) Developing a tissue plane between the rib periosteum and pleura, 4) Osteotomizing the lateral and medial portions of the rib to harvest the graft with a cartilage cap, 5) Inspecting for pleural tears and closing layers. Costochondral grafts are useful for reconstructing craniofacial and TMJ defects due to their growth potential in children and biocompatibility. Complications can include pneumothorax, fracture, and scar formation
The document discusses reconstruction of the temporomandibular joint (TMJ) through various methods including autogenous grafts, alloplastic devices, distraction osteogenesis, and tissue engineering. Autogenous grafts that can be used include costochondral grafts, iliac crest grafts, fibular grafts, and coronoid process grafts, each with advantages and limitations. Alloplastic devices made of various materials are also discussed, including the Kent-Vitek prosthesis, Christensen's prosthesis, and TMJ Concepts prostheses. Distraction osteogenesis is described as a method to reconstruct the mandibular ramus through gradual distraction. Tissue engineering is mentioned as a potential future approach involving scaffolds
Journal club on Mandibular fracture after third molarDr Bhavik Miyani
1) The document summarizes a journal club presentation on a study analyzing factors leading to mandibular fractures after third molar removal.
2) Six patients who experienced mandibular fractures on average 14 days after third molar surgery were examined. All patients were fully dentulous and between 42-50 years old.
3) The study found that advanced age combined with a full dentition were major risk factors for this complication. Pre-existing bone lesions from cysts or other issues also increased the risk of fracture by weakening the mandible.
The document provides an overview of the surgical anatomy of the mandible. It discusses the parts and features of the mandible, including the body, rami, coronoid and condylar processes. It details the growth and development of the mandible from the prenatal period through adulthood. Key anatomical structures are described, such as ligaments, muscles, nerves, blood vessels and lymph nodes associated with the mandible. Clinical considerations for surgical procedures involving the mandible are also mentioned.
The document discusses prenatal and postnatal growth of the mandible. It describes how the mandible develops from mesenchymal condensations in the pharyngeal arches during prenatal development. It forms through both intramembranous and endochondral ossification. The condyle, coronoid process, and mental region develop through endochondral ossification of cartilage models. Postnatally, the mandible grows downward and forward through appositional bone growth at the condyle, ramus, and alveolar processes to accommodate the permanent dentition. The chin develops through periosteal bone apposition on the lingual surface in males during late growth.
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.
The document discusses the development of the mandible from early embryogenesis through postnatal growth. It begins with the formation of Meckel's cartilage from the first pharyngeal arch which later contributes to mandibular formation. Ossification begins around the mental nerve and spreads to form the body and ramus. Secondary cartilage appears including the condylar, coronoid, and symphyseal cartilage. The mandible continues developing after birth through remodeling processes like at the condyle which causes downward and forward growth of the mandible.
ANATOMY,DEVELOPMENT AND CLINICAL CONSIDERATION OF MandibleSoni Bista
The document provides details on the anatomy of the mandible. It discusses the mandible's formation, parts, structures, development, ossification process, and age-related changes. The mandible is the largest and strongest bone in the facial skeleton. It forms the lower jaw and holds the lower teeth in place. The body of the mandible is horseshoe-shaped and has an external and internal surface. It articulates with the temporal bone at the temporomandibular joint to form the lower jaw.
This document discusses prenatal and postnatal growth and development of the mandible. It describes the three phases of prenatal life and outlines the formation and development of structures like the pharyngeal arches, meckel's cartilage, and bones in the mandible through intramembranous and endochondral ossification. It also discusses changes that occur in mandibular growth patterns after birth through childhood and adolescence, including growth at specific sites like the condyle, ramus, and alveolar process.
The document provides an overview of the mandible, including its anatomy, development, age-related changes, growth, muscle attachments, nerve and blood supply, and developmental anomalies. Key points include:
- The mandible develops from intramembranous ossification and has important growth sites at the condylar cartilage, borders of the rami, and alveolar ridge.
- Growth and remodeling of the condyle, rami, coronoid process, and angle allow the mandible to increase in length, height and flare with age.
- Muscle attachments including the masseter, temporalis, and lateral and medial pterygoids allow movements like elevation, protraction and grinding of the mand
This document provides an overview of the mandible, including its development, anatomy, age-related changes, and clinical applications. It discusses how the mandible develops from the first pharyngeal arch and ossifies through both intramembranous and endochondral bone formation. The anatomy of the mandible is described in detail, including its various parts and structures. Age-related changes to the mandible from birth through adulthood and old age are also reviewed. Finally, the document discusses some applied clinical aspects of the mandible relating to dislocations, fractures, and considerations for surgery.
This document provides an overview of the mandible, including its development, anatomy, age-related changes, and clinical applications. It discusses how the mandible develops from the first pharyngeal arch and ossifies through both intramembranous and endochondral bone formation. The anatomy of the mandible is described in detail, including its various parts and surrounding structures. Age-related changes to the mandible from birth through adulthood and old age are also reviewed. Finally, the document discusses some applied clinical aspects of the mandible relating to dislocations, fractures, and considerations for surgery.
Growth of mandible /certified fixed orthodontic courses by Indian dental aca...Indian dental academy
The document discusses prenatal and postnatal growth of the mandible. Prenatally, the mandible develops through intramembranous and endochondral bone formation from mesenchymal condensations in the pharyngeal arches. Specific regions like the condyle, coronoid process and mental region form through endochondral ossification of cartilage models. Postnatally, the mandible continues growing through apposition at the condyle, ramus borders and alveolar process to accommodate the permanent teeth and maintain jaw dimensions and shape under muscular influences. Growth patterns differ between males and females, with more prominent chin development in males near maturity.
The document summarizes the growth and development of the mandible from prenatal to postnatal stages. During prenatal development, the mandibular arch forms and fuses in the midline to form the mandible. Ossification begins from centers on each side and spreads. The condyle and coronoid process show endochondral bone formation. Postnatally, remodeling occurs throughout the mandible through bone deposition and resorption to accommodate tooth eruption, muscle growth, and maintain articulation with the cranial base as the face grows. Growth centers like the condyle, ramus, and coronoid process contribute to mandibular lengthening and shaping through adolescence.
The document discusses the growth and development of the mandible. It begins with an overview of the prenatal development, including how the mandibular arch forms from the pharyngeal arches and contains Meckel's cartilage. Meckel's cartilage provides a template for the mandible to develop around it through intramembranous ossification beginning in the 7th week of prenatal development. The mandible continues developing and forming after birth through both intramembranous and endochondral ossification.
“Growth was concieved by an anatomist, born to a biologist, delivered by a physician, left on a chemist doorstep, and adopted by a physiologist.At an early age- she eloped with a statistician, divorced him for a psycologist, and is now wooed, alternatively and concurrently, by an endrocrinologist, a biochemist,a physicist, a mathematician, an orthodontist, a eugenicist and the children’s bureau”.
THE PRENATAL LIFE IS DIVIDED INTO THREE PERIODS –
1.PERIOD OF THE OVUM
2.PERIOD OF THE EMBRYO
3.PERIOD OF THE FETUS
About the fourth week of intrauterine life, the pharyngeal arches are laid down
The first arch is called the mandibular arch and the second arch the hyoid arch.
The maxilla develops through both intramembranous and endochondral ossification prenatally. Around 4 weeks, the maxillary processes develop from the first branchial arches and grow medially to form the lateral walls of the primitive mouth. The palate develops from the maxillary processes, which give rise to the palatal shelves beginning around 6 weeks. The palatal shelves initially grow vertically but then reorient horizontally between 7-8 weeks to fuse in the midline and form the secondary palate by 8.5 weeks.
The document discusses the development of the mandible from early embryonic stages through adulthood. It begins with the formation of Meckel's cartilage from the first pharyngeal arch during the 4th week of development. Intramembranous ossification begins around the 7th week to form the body of the mandible. Secondary cartilages, including the condylar, coronoid, and symphyseal cartilages, contribute to further growth and shaping of the mandible. The alveolar process develops in response to erupting teeth. Throughout life, the mandible undergoes changes in shape due to growth and remodeling. Developmental disturbances can result in conditions like agnathia, micrognathia
The document discusses the development of the mandible and maxilla. It begins by explaining that the mandible develops from Meckel's cartilage in the first branchial arch, with intramembranous ossification forming the body and endochondral ossification contributing to growth. Secondary cartilages, like the condylar cartilage, aid further growth. The maxilla develops via intramembranous ossification from the maxillary process, with the premaxilla developing separately and fusing later. Both bones form alveolar processes to surround developing tooth buds. Their shapes and positions change with age as growth and remodeling occur.
This document discusses the prenatal and postnatal growth and development of the mandible. It begins with an overview of the anatomy of the mandible. During prenatal development, the mandible originates from Meckel's cartilage in the first pharyngeal arch. Ossification begins with intramembranous bone formation followed by endochondral ossification at sites like the condyle. Postnatally, the mandible grows through bone remodeling at sites like the ramus, condyle and chin, leading to changes in shape with age. Developmental defects can restrict this growth, resulting in a narrow mandible with an inwardly rotated ramus.
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.
Executive Directors Chat Leveraging AI for Diversity, Equity, and InclusionTechSoup
Let’s explore the intersection of technology and equity in the final session of our DEI series. Discover how AI tools, like ChatGPT, can be used to support and enhance your nonprofit's DEI initiatives. Participants will gain insights into practical AI applications and get tips for leveraging technology to advance their DEI goals.
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
How to Fix the Import Error in the Odoo 17Celine George
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1. SURGICAL ANATOMY OF
MANDIBLE
By: Dr. A. Shalini Sampreethi
Sr. Lecturer
Oral and Maxillofacial Surgery
MNR Dental College and Hospital
2. CONTENTS
• INTRODUCTION
• DEVELOPMENT AND GROWTH OF MANDIBLE
• ANATOMY OF MANDIBLE
• ATTACHMENTS AND RELATIONS OF MANDIBLE
• VASCULAR SUPPLY AND NERVE SUPPLY
• AGE CHANGES OF MANDIBLE
• APPLIED ASPECTS
• CONCLUSION
• REFERENCES
3. INTRODUCTION
• 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.
4. GROWTH AND DEVELOPMENT OF MANDIBLE
Growth and development of an individual is divided
into two periods.
Prenatal period
Post natal period
5. PRENATAL GROWTH PHASE
About the fourth week of intrauterine life,the
pharyngeal arches are laid down.
The first arch is called the mandibular arch and
the second arch the hyoid arch.
6. • About the 4th week of IU life, the developing brain
& pericardium form two prominent bulges which are
separated by the primitive oral cavity or
stomodeum.
• The floor of stomodeum is formed by the bucco-
pharyngeal membrane, which separates it from
forgut.
• Pharyngeal arches are laid in approximation with
stomodeum.
7. • Each arch has
1. Outer covering of ectoderm.
2. An inner covering of endoderm.
3. Core of mesoderm.
• Arches are separated from each other by
1.Pharyngeal cleft or groove externally.
2.Pharyngeal pouches internally.
8. Each of these five arches contain
A central cartilage rod that form the skeleton of
the arch.
A muscular component termed as bronchomere.
A vascular component.
A neural element.
9. • The development of face
begins in the 4th to 8th week
of intra-uterine life.
The face is derived from
An unpaired frontonasal
process.
A pair of Maxillary process.
A pair of Mandibular process.
10. • Mandibular arch gives of a
bud from dorsal end called
maxillary process.
It grows ventro-medially
called mandibular process.
• Mandibular processes of both
sides grow towards each other
& fuse in midline.
11. INTRAMEMBRANOUS BONE FORMATION
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.
12. At around 36 -38 days of intrauterine life there is
ectomesenchymal condensation.
Some mesenchymal cells enlarges , acquire a
basophilic cytoplasm and form osteoblasts.
These osteoblasts secrete a gelatinous matrix
called osteoid and result in ossification of an
osteogenic membrane.
13. The resulting intramembranous bone lies lateral to
meckel’s cartilage of first [mandibular] arch.
In the sixth week of the intrauterine life a single
ossification centre for each half of the mandible
arises in the bifurcation of inferior alveolar
nerve into mental and incisive branches.
14. During seventh week of intrauterine life bone begin
to develop lateral to meckel’s cartilage &
continues until the posterior aspect is covered
with bone.
Between eigth & tewelth week of intrauterine life
mandibular growth accelerate , as a result
mandibular length increses.
15. Ossification stops at a piont , which later become
mandibular lingula, the remaining part of meckels
cartilage continues to form sphenomandibular
ligament & spinous process of sphenoid.
Secondary accessory cartilage appear between tenth
& fourteenth week of intrauterine life to form head
of condyle , part of coronoid process & mental
protuberance.
17. THE CONDYLAR PROCESS:
At fifth week of intruterine life , an area of
mesenchymal condensation is seen above the ventral
part of developing mandible.
At about tenth week it develops in cone shaped
cartilage.
It migrate inferior & fuses with mandibular ramus
at about 4 month.
18. • This cone shaped cartilage is replaced by bone but
its upper end persists acting as growth cartilage &
articular cartilage.
19. THE CORONOID PROCESS-
Secondary accessory cartilage appear in region of
coronoid process at about 10- 14 week of
intrauterine life.
This cartilage become incorporated into
expanding intramembranous bone of ramus &
dissapear before birth.
20. THE MENTAL REGION:
In mental region , on either side of symphysis ,
one or two small cartilage appear and ossify in
seventh week of intrauterine life to become mental
ossicles.
These ossicles become incorporated into
intramembranous bone when symphysis ossify
completely.
21. POST NATAL GROWTH PHASE
At birth the two rami of the mandible are short ,
condylar development is minimum and there is no
articular eminence in glenoid fossa. A thin layer
of fibrocartilage & connective tissue exists at the
midline of symphysis to separate right & left
mandibular bodies.
At fourth month of age and end of first year
symphysial cartilage is replaced by bone.
22. • During first year of life appositional growth is
active at alveolar border, at distal & superior
surfaces of the ramus, at the condyle, along the
lower border of mandible and on its lateral
surface.
23. After first year of life these changes occurs :
Mandibular growth become more selective ,condyle shows
considerable activities , mandible moves and grows downward
& forward.
Appositional growth occurs on posterior border of the ramus
and on the alveolar process.
Resorption occurs along the anterior border of ramus
lenthening the alveolar border & maintaining the anterior-
posterior dimension of ramus.
24.
25. Gonial angle changes after little muscle activity.
Transverse dimension is mainly due to growth at posterior
border in an expanding V pattern.
26. The two rami also diverge
outward from below to above
so that additive growth at
coronoid notch , coronoid
process &condyle also
increses the superior inter-
ramus dimension.
Alveolar process of mandible
grows upward & outward on an
expanding arc. This permit
dental arc to accommodate the
larger permanent teeth.
27. Scott divides the mandible into three basic types
of bone:
1) Basal
2) Muscular
3) Alveolar
Basal portion is tube like central foundation
running from condyle to the symphysis.
Muscular portion [gonial angle &coronoid process]
is under influence of masseter, internal pterygoid
& temporal muscle. They determine the ultimate form
of the mandible in these areas.
28. Alveolar portion exists to hold the teeth &
gradually resorbed in the event of tooth loss.
Reduced muscular activity would account for
flattening of gonial angle and reduction of the
coronoid process.
29. MOSS say that the mandible as a group of
microskeleton unit:
Coronoid process as one skeleton unit under
influence of temporalis.
Gonial angle is another skeleton unit under
influence of massetor & internal pterygoid
muscles.
Alveolar process is under the influence of the
dentition.
Basal tubular portion of mandible serves as
protection for the mandibular canal and follows
a logarithim spiral in its downward & forward
movement from beneath the cranium.
30.
31. THE CHIN:
Enlow & harris feel that chin is “associated with a
generalised cortical recession in the flattened
regions positioned between the canine teeth. The
process involves a mechanism of endosteal cortical
growth.”
On lingual surface, behind the chin heavy
periosteal growth occurs , with the dense lamellar
bone merging and overlaping on the labial side of
the chin.
32. • In male , the apposition of the bone at symphysis
seems to be about the last change in shape during
the growing period. This change is much less
apparent in the females.
34. BODY OF MANDIBLE
• It is U or Horse shoe shaped and consists of 2 surfaces and 2 borders
A. OUTER SURFACE :
1. Symphysis Menti : The line at which the right and left halves of the
bone meet each other. It is marked by a faint ridge
2. Mental Protuberance : median triangular projecting area in the lower
part of the midline
3. Mental Foramen : It lies below the interval between the premolar
teeth.
4. External oblique Line : Continuation of the sharp anterior border of
the ramus of mandible.
5. Incisive Fossa / Mental Fossa : Depression that lies just below the
incisor teeth
35.
36. B. INNER SURFACE:
1. Mylohyoid line : Prominent ridge that runs
obliquely downwards and forwards from below the third
molar tooth to the median area below genial tubercle.
2. Submandibular fossa : It lies below the mylohyoid
line, which lodges the submandibular gland.
3. Sublingual fossa : It lies above the mylohyoid
line, which lodges the sublingual gland.
4. Genial tubercles : Posterior surface of the
symphysis menti is marked by four small elevations
called the superior and inferior tubercle.
5. Mylohyoid groove : Extends from ramus to the body
below the posterior end of the mylohyoid line.
6. Digastric fossa : Near the midline the base shows
an oval depression.
37.
38. Superior Border :
It is hollowed into Sockets for the reception of
the teeth.
They vary in depth and size according to the
containing teeth.
Inferior Border :
Also called Base of the mandible.
It is rounded, longer than the superior , and
thicker in front than behind.
39. RAMUS OF MANDIBLE
It is quadrilateral in shape and it has
A. 2 surfaces
1.Lateral
2.Medial
B. 4 borders
1.Superior
2.Inferior
3.Anterior
4.Posterior
C. 2 processes
1. Coronoid
2. Condylar
40. Lateral surface :
flat and bears number of oblique ridges
Medial surface :
1. MANDIBULAR FORAMEN : It lies little above the
centre of ramus at the level of occlusal plane.
It leads into mandibular canal which opens at
mental foramen.
2. LINGULA : Anterior margin of foramen marked by
tongue shaped projection.
3. MYLOHYOID GROOVE : Begins just below mandibular
foramen, runs forwards and downwards to be
gradually lost over the submandibular fossa.
41.
42. Anterior Border :It is thin above
and continuous with coronoid
process , and thick below and is in
continuation with oblique line.
Posterior Border : It is thick,
rounded & extends from condyle to
angle and is in contact with
Parotid gland.
Upper Border : It is thin and
Curved downwards forming Mandibular
notch and is surmounted by coronoid
process in front and condylar
process behind.
.
43. Lower Border : It is thick,
straight and is backward
continuation of base of
mandible.
Posteriorly it ends by
becoming continuous with
posterior border of angle of the
mandible.
Typically everted but inverted
in females.
44. Coronoid process
It is flattened triangular
upward projection from the
antero-superior part of ramus.
Anterior border is continuous
with anterior border of ramus ,
and is palpable below zygoma
while while opening mouth.
Posterior border bounds the
mandibular notch.
45. Condylar process:
It is strong upward
projection from the postero-
superior part of ramus.
Upper end is expanded side
to side to form head.
Head is covered with
fibro cartilage and
articulate temporal bone to
form TMJ .
Constriction is seen below
head is neck.(its anterior
surface has depression
called pterygoid fovea)
It is convex in all
directions.
Medial part articulates with
Mandibular fossa of temporal
bone.
46. Lateral aspect is blunt
and palpable in front of
tragus.
Lateral part is separated
from cartilagenous external
accoustic meatus by Parotid
gland.
Lateral surface of neck
provides attachment to
lateral ligament of TMJ.
47. ATTACHMENTS AND RELATIONS OF MANDIBLE
1. OUTER SURFACE OF MANDIBLE
• External oblique line - origin to buccinator,
depressor inferioris, depressor anguli oris.
• Incisive fossa - origin of mentalis, mental slips of
orbicularis oris.
• Lateral surface of ramus - insertion for masseter.
• Lower border - deep cervical fascia and platysma.
• Postero-superior lateral surface of ramus - parotid gland.
• Lateral surface of neck - attachment to lateral ligament of
temperomandibular joint , parotid gland.
48.
49. 2. INNER SURFACE OF MANDIBLE
• Mylohyoid line - origin to mylohyoid muscle , attachment to superior
constrictor of pharynx, pterygomandibular raphae.
• Medial surface of ramus - medial pterygoid muscle attachment.
• Superior genial tubercles – genioglossus.
• Inferior genial tubercles – origin to geniohyoid.
• Lingula - sphenomandibular ligament.
• Apex of coronoid process - temporalis attachment.
•
• Pterygoid fovea - lateral pterygoid muscle.
• Diagastric fossa - anterior belly of diagastric.
50.
51. FORAMINA & OTHER RELATIONS
• Mental foramina - mental nerve and vessels.
• Mandibular notch - massetric nerve and vessels.
• Medial side of neck - auriculo temporal nerve.
• Mylohyoid groove - mylohyoid nerve and vessels.
• Mylohyoid groove in front of ramus - lingual nerve.
• Mandibular canal and foramina - inferior alveolar nerve and
vessels.
• Area above and behind mandibular foramen – Maxillary artery.
55. 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 :
a) Lingual branch
b) Mylohyoid branch
c) Incisive branch
d) 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.
56.
57. VENOUS SUPPLY OF MANDIBLE
Drains into Internal Jugular vein and
External Jugular vein through Maxillary vein,
Facial vein and pterygoid plexus.
58. LYMPHATIC DRAINAGE OF MANDIBLE
• Most of the mandible and lower teeth drain into Sub
mandibular group of lymphnodes.
• A small wedge in the symphysis region and lower
incisors drain into Sub mental lymph nodes.
Sub Mental group
Sub mandibular
group
Jugulo-omohyoid
group of deep
cervical nodes
Posterior
group of sub
mandibular
nodes
Jugulo
digastric
group of
deep
cervical
nodes
59.
60. NERVE SUPPLY OF MANDIBLE
• Mainly supplied by Mandibular division of Trigeminal nerve
MANDIBULAR DIVISION (sensory root)
• UNDIVIDED NERVE DIVIDED NERVE
- Nervous spinosus (meningeal)
- Nerve to medial pterygoid
Anterior Division Posterior division
- Nerve to Lat. Ptgd - Auriculotemporal
-Nerve to masseter - Lingual
-Nerve to Temporal - Mylohyoid
-Buccal nerve - IAN : 1.Mental
2.Incisive
61. • Motor root of Trigeminal nerve passes along with V3
and supplies :
1. Muscles of mastication
2. Mylohyoid
3. Anteror belly of digastric
4. Tensor tympani
5. Tensor veli palatini
• Marginal mandibular branch of facial nerve runs below
the angle of mandible deep to platysma and supplies to
muscles of lower lip and chin.
62.
63. MUSCLES RELATED TO MANDIBLE
• Muscles of facial expression: 1.Buccinator
2.Mentalis
3.Depressor anguli oris
4.Depressor labii inferioris
5. Platysma
• Muscles of mastication : 1.Temporalis
2.Masseter
3.Lateral pterygoid
4.Medial pterygoid
• Geniohyoid
• Genioglossus
• Anterior belly of digastric
• Superior constrictor of pharynx
65. • RETRACTION : 1. Temporalis
(Posterior horizontal fibres)
2. Masset er
(Deep vertical fibres)
• LATERAL SIDE TO SIDE :
1. Left side : Right lateral and medial pterygoid;
Left Masseter and temporalis
2. Right side : Left lateral and medial pterygoid;
Right Masseter and Temporalis
68. APPROACHES TO MANDIBLE
• In mandibular pathologies and fractures there is
need for exposure to treat the site at the same
time maintaining its harmony and aesthetics.
• The various approaches include :
1. SUBMANDIBULAR APPROACH
2. SUBMENTAL APPROACH
3. VESTIBULAR APPROACH
4. PREAURICULAR APPROACH
5. ALKAYAT BRAMLEY INCISION
6. POST AURICULAR APPROACH
73. MUSCLE INJURIES
1. MYLOHYOID MUSCLE :
• Surgical manipulation of the floor of the mouth may
result in edematous swelling of sublingual space
(above mylohyoid muscle) and submandibular space
(below mylohyoid muscle)
• Cellulitis of sublingual space is quite common.
• Excessive bilateral cellulitis of sublingual space may
push the tongue backwards and compress the pharynx –
thus Airway obstruction.
74.
75. 2. GENIOGLOSSUS MUSCLE
During the elevation of the lingual mucosa before
making an impression for a subperiosteal implant a
portion of the muscle may be reflected from genial
tubercle.
If the muscle is completely detached from the
tubercle it may lead to retrusion of the tongue and
airway obstruction.
3. MEDIAL PTERYGOID MUSCLE
The medial pterigoid muscle binds the
pterigomandibular space medially ,during surgical
procedures involving the area of pterigomandibular
space infection may occur and may be dangerous due to
its closed proximity to the pharyngeal space.
76. Surgical exposure of the tissue posterior to the
maxillary tuberosity may also involve the medial
pterygoid muscle as a part of the muscle
originates from the maxillary tuberosity
3. LATERAL PTERYGOID MUSCLE
The lateral pterygoid muscle fibres are placed in
an angulated manner and because of this there may
be pain in patients with a full arched sub
periosteal implant or prosthetic splint.
77.
78. 4. MENTALIS
Complete reflection of the mentalis muscle for the
purpose of extension of a subperiosteal implant may
result in a condition known as witch’s chin
If there is failure of the mentalis muscle reattachment
following the implantation drooping of lower lip occurs.
An external bandage is applied for four days to help in
the reattachment of the muscle.
79. 5. BUCCINATOR MUSCLE
• Myositis of the detached buccinator muscle in
patients with subperiosteal implants may cause
swelling and pain at the site of origin of the
muscle.
80. 6. TEMPORALIS MUSCLE
• Surgical exposure medially
may injure tendon of
Temporalis while harvesting
bone from external oblique
ridge or placing incisions
for sub periosteal Implants.
7. MASSETER MUSCLE
• Masseteric space infections
may result during surgery to
expose bone for ramus
extension needed Implant.
81. NERVE INJURIES
1. INFERIOR ALVEOLAR NERVE
The nerve may be damaged
easily when making an
incision or reflection
of the mucosa in its
area therefore position
of the inferior dental
canal in vertical and
buccolingual dimension
is of great importance
during site preparations
for implants.
82. 2. LINGUAL NERVE
The position of the nerve
is medial to the retromolar
pad.
The incision should remain
lateral to the pad and the
mucosal reflection should
be done with a periosteal
elevator in constant
contact with the bone to
prevent injury to the
nerve.
Injury of nerve causes
causes ipsilateral
paraesthesia , loss of
taste and reduction of
salivary secretion.
83. 3. MYLOHYOID NERVE
The nerve lies in
closed relation to
the ramus of
mandible hence it
is prone to get
damaged during
surgical
intervention.
84. 4. LONG BUCCAL
NERVE
When the ramus
is accessed
for the
purpose of a
block graft
excision great
care must be
take to
protect this
nerve from
injury.
85. 5. MENTAL NERVE
Tremendous variation in
the position of mental
nerve seen.
In preprosthetic surgery
nerve repositioning is
done as nerve is present
more towards alveolar
border in old age.
Injury to nerve causes
paresthesia of skin of
chin, lower lip and
labial mucosa.
86. VASCULAR INJURIES
1. INFERIOR ALVEOLAR
VESSELS
During surgical
orthognathic surgery
procedures, the major
nutrient vessels of
mandible can sometimes get
damaged.
2. FACIAL ARTERY
Facial artery preservation
is important while giving
sub mandibular incisions.
89. MANUAL REDUCTION :
• Downward pressure followed by posterior and
upward movement.
90. FRACTURES OF MANDIBLE
• Most weakest point of mandible is canine socket area (
due to long canines) and next common site is Angle.
(due to presence of impacted molars)
• Bilateral parasymphysis fracture can cause airway
obstruction if associated with loss of consciousness.
• With advancing age resorption of alveolar process and
decrease in vertical height thereby making it prone to
fracture.
• Slender neck of condyle makes it liable to fracture as
a result of direct violence to chin- this acts as
safety mechanism to prevent injury to mid cranial
fossa.
• Sideway blow causes fracture of opposite condyle along
with same side parasymphysis fracture.
91. Sagittal split osteotomy – splitting the ramus of
mandible bilaterally in sagittal plane for
correcting micrognathia
osteomyelitis is more common in mandible than
maxilla as it has rich blood supply
92. # OF ANGLE OF MANDIBLE
• It is second common site of fracture after condyle
• It is impotant to distingiush i) Clinical angle
ii) Surgical angle
iii) Anatomical angle
• CLINICAL ANGLE : It is the junction between alveolar bone and
ramus at the orijin of internal oblique line.
• SURGICAL ANGLE : Junction between body of the mandible and
ramus at the external oblique ridge.
• ANATOMICAL OR GONIAL ANGLE : Here the lower border meets the
posterior border of ramus.
93. SPACE INFECTIONS RELATED TO MANDIBLE
• Submandibular space infection
• Sub mental space infection
• Pterygomandibular space infection
• Sublingual space infection
• Buccal space infection
• Masseteric space infection
• LUDWIGS ANGINA – bilateral cellulitis involving sub
mandibular, submental and sublingual space.
94. SYNDROMES ASSOCIATED WITH MANDIBLE
• Mandibulofacial Dysostosis or Treachers collin
syndrome – Bird like face (Hypoplasia of mandible)
• Crouzons syndrome – Psedoprognathism (maxillar
retrusion)
• Apert syndrome – Psedoprognathism with open bite
(mid face hypoplastic)
• Hemicraniofacial microsomia – Short mandibular
ramus (chin deviation , micrognathia)
• Pierre robin syndrome – Retrognathic mandible
95. SURGICAL CONSIDERATION
Mandibular canal Partially or completely
edentulous cases→ placement of implants difficult.
Injury to the mental nerve paraesthesia to the
skin of the chin, the lower lip and the labial
mucosa.
Injury to the lingual nerve during flap reflection,
releasing incisions, anesthestic injections.
96. External oblique ridge:
Resective surgery difficult because of the amount
of bone to be removed.
Apical positioning of the flap is difficult in
these areas.
A high buccinator attachment results in a shallow
vestibule, making grafting procedures difficult.
97. Mandibular tori:
The mucosa over the tori region is usually thin and
hence is subject to tearing.
Source of autogenous bone for grafting procedures.
98. Mylohyoid ridge:
A prominent ridge may →broad bony ledge resulting
in limited surgical access and also makes flap
reflection difficult.
99. Coronoid process:
• A prominent coronoid process may be in close
proximity to the maxillary tuberosity
resulting in limited surgical access
Genial tubercle:
• In cases of severe horizontal bone loss they
may pose a problem during implant placement
and flap reflection
Alveolar process:
• Prominent teeth results in marginal tissue
recession, bony dehiscence or fenestration
100. CONCLUSION:
• The selection of an appropriate surgical technique
that can best satisfy the treatment goals &
objectives is directly influenced by through
knowledge of anatomic relations between bone, soft
tissues & teeth. The study of anatomy of mandible &
surrounding structures is essential.
101. REFERENCES:
• Gray’s anatomy, 38th edition.
• Human anatomy, B.D Chaurasia, 7th edition.
• Essentials of human anatomy, A.K Datta, 2nd edition
• Human Embryology , I B Singh
• Contemporary orthodontics ,Proffit ,4th edition.
• Text book of orthodontics ,S.I Bhalaji ,3rd edition.
• Text book of Oral and Maxillofacial Surgery , Laskins.
• Text book of Oral and Maxillofacial Infections
,Topazain.