The Forehead

The Forehead

The forehead (Latin: sinciput) is a part of the head bounded by three features – one of the scalp and two of the skull. It constitutes the upper third of the face. Hairline, which represents the edge of the area where hair grows, marks the top of the forehead, while the bottom of the forehead is marked by the supraorbital ridge. That is the bone feature just above the eyes. When it comes to the sides of forehead, there are temporal ridges which are marking it. These temporal ridges represent also a bone feature which links the supraorbital ridge to the coronal suture line and beyond.

Structure

The forehead comprises the Squama Frontalis – the plate-like portion of the frontal bone of the skull. The sensory nerves of the forehead lie within the subcutaneous fat. They are connected to the ophthalmic branch of the trigeminal nerve and the cervical plexus, while the motor nerves are connected to the facial nerve. The musculature of the forehead comprises the occipitofrontalis, procerus, and corrugator supercilii muscles. The temporal branch of the facial nerve mentioned above controls all of them. Left and right supraorbital, supertrochealar, and anterior branches of the temporal artery supply blood to the forehead.

The supraorbital nerve divides into two parts in the forehead – the superficial division, which provides sensation for the skin on the forehead and front edge of the scalp, and the deep division, which provides frontoparietal sensation.

Functions of the forehead

Expression

With the help of muscles of the forehead facial expressions are formed. There are four basic motions. They could occur individually or in combination, in order to form different expressions. The best example is following: the occipitofrontalis muscles can raise the eyebrows. They could be raised either together or individually, aiming different expression: surprise or suspect. Of course, there are other examples like pulling the eyebrows inwards and down with the help of the corrugator supercilii muscles, so that person can express a frown.

Wrinkles

The movements of the muscles in the forehead cause appearing of the wrinkles in the skin. The occipitofrontalis muscles are “guilty” for the transverse wrinkles across the width of the forehead, while the corrugator supercilii muscles cause vertical wrinkles between the eyebrows. Lastly, the procerus muscles help in process of the nose wrinkling.

 

Interesting facts

  • It is believed that form of the forehead reflects the character of a person. So, following the belief, person with the high brow (brow=forehead) has a superior intellect and is sophisticated. On the other hand, low brow is associated with primitive species of humanity and indicates primitivism and ignorance.
  • Another interesting thing about forehead is that it is believed to be a site of spirituality in some religions. The center of the forehead in Hindu tradition is, as you all probably know, the location of a third eye. In other words it is the location of spiritual insight. Also, Hindu gods are mostly represented with a third eye in the middle of their foreheads. Muslims are touching their foreheads to the floor when bowing toward Mecca. In addition, some Tibetan meditation practices focus on the center of the forehead.

 

The Human Body

Entire structure of a human being is called the human body. It includes a head, neck, trunk (which includes the thorax and abdomen), two arms and hands and two legs and feet. Also, every part of the body is composed of various types of cells. There are about 37.2 trillion of them in the whole body. This number is considered a partial data and can be used as a starting point for further calculations. The study of the human body involves anatomy and physiology.

 

Structure

Skeletal structure frames the shape of the body. It’s main characteristic is that it doesn’t alter much over a lifetime. General body shape is influenced by the distribution of muscle and fat tissue. Also, it can be affected by various hormones. The average height of an adult male human is about 1.7–1.8 m and of the female is about 1.6–1.7 m.  Genes and diet largely determine height, while genetics, diet and exercise mostly influence body type and composition.

 

The human body has several body cavities. The largest one is the abdominopelvic cavity. Various body organs are located in these cavities, including the spinal cord.  There are also many other smaller cavities which are called sinuses. Sinuses have variety of functions, but if we take in consideration general usage it refers to the paranasal sinuses. They are involved in the condition sinusitis. The paranasal sinuses are four pairs of vital air-cavities in the cranial bones. These air-filled spaces are paired between the eyes, above the eyes, deeper behind the eyes and around the nasal cavity.

 

Composition of the human body

The main elements of the human body are going to be shown in the following order: from most abundant to least abundant.

The average adult body contains between 5 and 5½ liters of blood. Also, there is around ten liters of interstitial fluid, which surrounds cells and all tissue spaces. Another important thing in human body is water. There is approximately 60% of water in adult human body. Of course, water content can vary from 75-45%, depending on age.

The proportions of the elements of the body can be referred to in terms of the main elements, minor ones and trace elements. Furthermore, when we talk about material type, it can include water, protein, connective tissue, fats, carbohydrates and bone.

 

Human anatomy as study

The best definition of human anatomy is that it is scientific study of the morphology of the human body. Anatomy is subdivided into gross anatomy and microscopic anatomy. Gross anatomy represents the study of anatomical structures that can be seen by the naked eye. On the other hand, microscopic anatomy involves usage of microscopes.

 

Systems

The human body consists of many systems that interact. Each system contributes to the maintenance of itself, other systems, and the entire body.  A system consists of two or more organs. Systems do not work in isolation so the interaction is very important for the person and its health. Some systems are known by their joint names. For example – the nervous system and the endocrine system is known together as the neuroendocrine system.

 

The nervous system

It consists of the central and peripheral nervous system. Central nervous system includes the brain and the spinal cord. The brain is one of the most important organs – controls various systems and functions, emotions, memory, thoughts, communication etc.  The special senses are vision, hearing, taste and smell and the organs, which help gathering information about environment, are eyes, ears, tongue and nose.

The musculoskeletal system

This system can be divided into skeletal and muscular system. It consists of human skeleton and muscles. Human skeleton includes bones, ligaments, tendons and cartilage. This gives the body its structure and movement ability. Also, larger bones contain bone marrow, which produces blood cells. Another important role of this system, or to be precise of the bones, is their function of storing the calcium and phosphate.

The circulatory system

This system is also known as cardiovascular system. It comprises the heart and blood vessels (arteries, veins and, lastly, capillaries). The heart’s function is propelling the circulation of the blood. The blood serves for transportation of the oxygen, fuel, nutrients, waste products, immune cells and signaling molecules, such as hormones.

The respiratory system

This system consists of the nose, nasopharynx, trachea and lungs. Its function is bringing the oxygen from the air and excreting the carbon dioxide and water back.

The digestive system

Main parts of this system are mouth, esophagus, stomach, gut, liver, pancreas, gallbladder and salivary glands. Mouth itself includes tongue and teeth. Converting food into nutritional, non-toxic molecules and distribution (done by the circulation) are its primer functions. In addition, it excretes the unused residue.

The integumentary system

Covering of the body (skin) is what this system is consisted of. It also includes hair and nails, as well as the sweat glands and sebaceous glands. The skin provides containment, protection, structure and serves as a sensory interface.

The urinary system

The urinary system includes kidneys, ureters, bladder and urethra. It produces urine from remaining water from the bloods and carries it out from the body. This urine carries many waste molecules and excess ions in it.

The reproductive system

The reproductive system is also known as a genital system. This is a system of sex organs (gonads and the internal and external sex organs) which main purpose is sexual reproduction. Fluids, hormones, and pheromones are also important accessories to the reproductive system.

The immune system

The immune system consists of the white blood cells, the thymus, lymph nodes and lymph channels. It provides a mechanism for the body to distinguish its own cells and tissues from alien cells. This way those alien cells could be neutralized or destroyed.

The lymphatic system

The main function of this system is to extract, transport and metabolize lymph. The lymph is fluid found in between cells. This system is similar to circulatory system in structure and basic functions.

The endocrine system

The endocrine system includes the pituitary, thyroid, adrenals, pancreas, parathyroids, and gonads. Still, almost all organs and tissues produce specific endocrine hormones as well. The endocrine hormones serve as signals from one system to another.

the human body in imageimage of human body

 

Tissue Of The Human Body

Human Body Tissue

Generally, tissue is a group of cells with similar shape and function. The functional grouping of multiple tissues forms organs – parts of the body that perform a definite function.  System, a group of organs, is the final unit of organization in the body.

Different types of tissues are found in different organs. In humans we have 4 basic types: epithelial, connective, muscular, and nervous tissue. In addition, there may be various sub-tissues within each of the primary tissues.

 

Epithelial tissue

Epithelial tissue covers the body surface. It protects your body from moisture loss, bacteria, and internal injury. Epithelial tissue functions include following: protection, secretion, absorption, and filtration.  There are two kinds of epithelial tissues:

  1. Covering and lining epithelium, which covers almost all internal and external body surfaces.
  2. Glandular epithelium, which main function is secreting of the hormones and other products such as stomach acid, sweat, saliva, and milk.

The organ that is made up of epithelial tissue is called skin. It protects the body from dirt, dust, bacteria and other microbes that could harm it. Cells of the epithelial tissue have different shapes.

Connective tissue

Connective tissue is the most prevalent of the tissues. It performs several functions including support and protection. This tissue in human body includes following:  ordinary loose connective tissue, fat tissue, dense fibrous tissue, cartilage, bone, blood, and lymph, which are all considered connective tissue.  There are two types of connective tissue:

  1. Loose connective tissue, which holds structures together. Best example of its function is holding the outer layer of skin to the underlying muscle tissue. Furthermore, this tissue could be found in fat layers, lymph nodes, and red bone marrow.
  2. Fibrous connective tissue, which also holds body parts together, but its structure is different in a way that it is a bit more rigid. It is located in ligaments, tendons, cartilage, and bone.

Muscle Tissue

Muscle tissue is different than all the other kinds of tissues. There are three types of them all made up of muscle fiber. The muscle fibers contain many myofibrils, which are the parts of the fiber that actually contract.

  1. Skeletal is a voluntary type of muscle tissue and it is attaches to bones. It causes movements of the body.
  2. Smooth is involuntary type of muscle tissue. It lines the walls of internal organs such as digestive and urogenital organs, and blood vessels.
  3. Cardiac is also involuntary type found only in the walls of the heart.

 

Nervous Tissue

Nervous tissue is composed of nerve cells which function is receiving of the stimuli and conduction of the impulses to and from all parts of the body. There are two kinds of nerve cells:

  1. Neurons, which are the basic structural units of the nervous system.
  2. Neuroglia, or glial cells, which provides support functions for the neurons.

 

Nervous tissue forms nervous system – system responsible for coordinating of the activities and movements of the body. This system consists of the brain, spinal cord and nerves.

The Neck And Its Anatomy

neck anatomy

Part of the body that distinguishes the head from the torso is called the neck. It is highly flexible, allowing the head to turn and flex in all of the directions. Also, the neck supports the weight of the head and protects the nerves.  It contains the cervical spine, many important blood vessels, the trachea, the larynx, the esophagus, lymph nodes, muscles, nerves, connective tissue and finally skin.

The neck is the start of the spinal column and spinal cord. The spinal column contains two dozen of bony segments which are connected, oddly shaped and called vertebrae. The neck contains seven of these and they are known as the cervical vertebrae. These are the smallest vertebrae in the body often referred to as C-1 to C-7.

The midline of the neck, in the front, has a prominence of the thyroid cartilage called the laryngeal prominence or better known Adam’s apple. Adam’s apple is more prominent in man. Reason for this is the fact that thyroid cartilage meets at a 90-degree angle, while in women the angle is typically 120-degrees.

Hyoid bone is located between the Adam’s apple and the chin. Next thing noticed below the thyroid cartilage, in the midline, is the cricoid cartilage. Furthermore, between the cricoid cartilage and the suprasternal notch there is the trachea and isthmus of the thyroid gland.

Even though there is the same amount of nerve endings in the neck as in the other areas of the body, it is considered to be an erogenous (erogenous = love giving) zone – area of the heightened sensitivity.  The main arteries in the neck are the common carotids, while the main veins of the neck are the external and internal jugular veins.

Also, there are approximately 300 of lymph nodes in the neck, which are also known as cervical lymph nodes.

The spinal column protects and houses the spinal cord, all the way from the base of the skull to the pelvis. The spinal cord is long bundle of nervous tissue, which transmits neural signals to the brain and body.

The structures in the neck allow us to speak. The larynx hosts the vocal cords and generates sound. Also, it manipulates pitch and volume by its movement. Location of the larynx is where the pharynx divides into the trachea and the esophagus. Pharynx is located on the back of the mouth and nasal cavity. Trachea is the tube that carries air to the lungs, while esophagus is the tube that carries food to the stomach.

The neck muscles, including the sternocleidomastoid and the trapezius, are responsible for movement of the head in every direction and for pulling the skull and jaw towards the shoulders, spine, and scapula. While working in pairs, they control the flexion and extension of the head and neck. On the other hand if working individually, these muscles rotate head or flex the neck laterally.

Anatomy of the Knee

anatomy of the knee

The knee is the largest joint in the human body. It joins the thigh with the leg and consists out of two articulations. These articulations are between the femur and tibia and between femur and patella. The femur and the tibia are both bones of the knee – first one is a thighbone and second is the main bone of lower leg. As already said, they form the knee together, while the patella (aka kneecap) protects the joint from the front. The knee allows flexion and extension and a slight internal and external rotation. Knee joint has not changed fundamentally over millennium and is still vulnerable to acute injury and the development of osteoarthritis.

STRUCTURE

The knee is a hinge type synovial joint. It is composed of three functional parts:

  • The femoropatellar articulation: which consists of the patella;
  • The patellar groove: which is located on the front of the femur through which it slides;
  • The medial and lateral femorotibial articulation: which links the femur and tibia.

Synovial membrane (called joint capsule) contains synovial fluid which surrounds the joint.

This part of the body is one of the most important. It plays significant role in movement (running, walking, jumping…)

Babies at birth don’t have conventional kneecap, but a growth formed cartilage, which is, by the child’s age of 3-5 years, going to be replaced with the bones.

  • Articular bodies: The articular bodies of the femur are its lateral and medial condyles.
  • Articular capsule: Articular capsule is wide, lax and thin in front and at the side. It contains the patella, ligaments, menisci, and bursae. The capsule consists of a synovial and a fibrous membrane.
  • Bursae: The bursae of the knee are the fluid sacs and synovial pockets that surround and sometimes communicate with the joint cavity. They represent the weak point of the joint, but also produce enlargements to the joint space. When it comes to structure, they are thin-walled and filled with synovial fluid.
  • Menisci: Menisci are the articular disks (two of them: the medial meniscus and the lateral meniscus) of the knee-joint. They only partly divide the joint space. These two disks consist of connective tissue with extensive collagen fibers containing cartilage-like cells.
  • Ligaments: The ligaments are surrounding the knee joint. Their function is offering stability by limiting movements. Also, ligaments together with several menisci and bursae protect the articular capsule. Ligaments are either intercapsular or extracapsular.
  • Cartilage: Cartilage is a thin, elastic tissue that protects the bone and provides sliding of the joint surfaces. Cartilage ensures supple knee movement.

Listed components of this part of the body, along with the muscles of the leg, work together to manage the stress in the knee caused by walking, running, jumping…

 

MUSCLES

All the muscles responsible for the movement of the knee joint belong to one of the following compartments of the thigh: anterior, medial or posterior.  The two main muscle groups of the knee joint are the quadriceps and the hamstrings.

The quadriceps muscle group is made up of four different individual muscles: biceps femoris, vastus medialis, vastus intermedius and vastus lateralis. Joined together they form the quadriceps tendon, which is connecting the muscle to the patella.  Contraction of the quadriceps pulls the patella upwards and extends the knee.

The hamstring muscles are located on the back of the thigh. They consist of biceps femoris, semitendinosus and semimembranosus. Their function is in flexing and bending the knee and providing the stability.

 

Human Shoulder

Human Shoulder

Human shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade) and the humerus (upper arm bone), and, of course, out of muscles, ligaments and tendons. The articulations between the bones of the shoulder form the shoulder joint. Glenohumeral is the main joint in shoulder.

There are two kinds of cartilage in the joint: white cartilage and the labrum. White cartilage is located on the ends of the bones, so it is also called articular cartilage. It allows bones to glide and move on each other. In time, this cartilage starts to wear out and that process is called arthritis. It causes joints to become painful and stiff. Second cartilage – the labrum – is distinctly different from the first type, mainly in structure. It is more fibrous than the cartilage on the ends of the ball and socket. The labrum is only found around the socket, where it is attached.

It is important for the shoulder to be mobile enough for the wide range actions of the arms and hands. On the other hand, it has to be stable enough to allow actions such as lifting, pushing and pulling. This is the main reason for number of shoulder problems (while other joints, such as the hip, don’t have that much).

 

STRUCTURES

JOINTS

As mentioned before, shoulder has three joints: the glenohumeral, acromioclavicular and the sternoclavicular.

  1. The glenohumeral joint is the main joint of the shoulder and the generic term “shoulder joint” usually refers to it. It is a ball and socket joint that allows the arm to rotate in a circular fashion or to hinge out and up away from the body.
  2. The acromioclavicular joint is also known as AC joint. It is located at the top of the shoulder. It represents the junction between the acromion (part of the scapula that forms the highest point of the shoulder) and the clavicle.
  3. The sternoclavicular joint occurs at the medial end of the clavicle (which is triangular and rounded) with the manubrium (which is convex) or top most portion of the sternum. The joint consists of a tight capsule and complete intra-articular disc, which ensures stability of the joint.

MUSCLES

The muscles that are responsible for movement in the shoulder are attached to the scapula, humerus, and clavicle. Those muscles that surround the shoulder form the shoulder cap and underarm.

The rotator cuff is a term given to the group of muscles and their tendons. They act to stabilize the shoulder by holding the head of the humerus (ball) in the glenoid fossa (socket).

 

FUNCTIONS

Both muscles and joints allow the shoulder to move through a range of motions. Due to that fact, shoulder is considered one of the most mobile joints in the human body, but also extremely unstable and prone to dislocation and injury. Possible shoulder motions are:  abduction, adduction (such as during the shoulder fly), rotation, rising in front of and behind the torso and moving through a full 360° in the sagittal plane.

Difference between male and female skeleton

MALE AND FEMALE SKELETON

Before we go deep into matter and start with analyzing of some parts separately, let’s note down some of the important facts about human skeleton.

 

INTERNAL BODY FRAMEWORK

Human skeleton is, as said in the title, internal framework of the body. At birth, there are 270 bones in it, but this number decreases to 206 as some bones coalesce by time. The skeleton reaches maximum density of the bone mass at the age of 30.

Skeleton is mostly divided into two parts: axial and appendicular skeleton. The axial skeleton is formed by the vertebral column, the rib cage and the skull. The appendicular skeleton, which is attached to the axial skeleton, is formed by the pectoral girdles, the pelvic girdle and the bones of the upper and lower limbs.

There are six essential functions of the skeleton. They are: support, movement, protection, production of blood cells, storage of ions and endocrine regulation.

 

GENDER DIFFERENCES

Even though other primate species’ skeletons are visibly and strongly sexually dimorphic, that is not the case with human. There are just subtle differences between skeletons of men and women. Those differences are mainly in morphology of the skull, dentition, long bones and pelvis. In general, elements of the female skeleton tend to be smaller and less robust, than male ones.

Anatomical differences between males and females are bigger in some soft tissue areas than in skeleton. As we said, human skeleton is not as sexually dimorphic as on other primate species.

Also, male and female bones develop at different rates. Everyone talks about girls getting mature before boys. This, of course, is referring to their emotional maturity, but is also true for the human skeleton. The bones in a female body complete their development sooner than those in the male body.

Now we will take a look at some of the specific parts of skeleton and see the differences.

Skull

A variety of morphological traits of the human skull demonstrate sexual dimorphism, such as the nuchal crest, mastoid processes, supraorbital margin, supraorbital ridge, and mental eminence.

Dentition

Human dental dimorphism is mostly seen on the canines, but this difference is small comparing to other great apes.

Long bones

Long bones are generally larger in male than female skeletons. Muscle attachments on long bones are usually stronger on men. This reflects on a difference in overall muscle mass and sexes.

Pelvis

The biggest different on male and female skeleton is seen on pelvis. The female pelvis is adapted for gestation: it is lower and proportionately wider than the male. The sacrum of the female is also wider. Furthermore, pelvic ring is wider and more circular, so that it can facilitate the passage of the newborn. Greater hip width in women influences the position of the thighbone, which is often more angled than in men. This gives them a bit of X shape.

Anthropologists commonly use the Phenice method to determine the sex of an unidentified human skeleton. It has 96% to 100% accuracy. This method is based on three characteristics of the pelvis: the ventral arc, sub-pubic concavity, and the medial aspect of the ischiopubic ramus.

Internal Parts of the Body

Heart

heart

Is an organ that pumps your blood throughout the blood vessels around your body. The blood is pumped by repeated rhythmic contractions. The heart in human body is located anterior to the vertebral column and posterior to the sternum. The average human heart beats 72 times per minute and weights between 250 and 300 grams.

 

Lung

Lung

Is the essential respiration organ. In every human body there are two lungs which are located near the backbone. The principal function of the lungs is the transportation of oxygen from the atmosphere into the bloodstream and the release of carbon dioxide from bloodstream into the atmosphere. When you breathe, the air goes into your lungs.

 

Veins

Veins

Are blood vessels and these transport blood through your body. They carry blood toward the heart. They are like little tubes which are located throughout the body often closer to the skin. Veins contain valves which help keeping blood flowing toward the heart. There are different classifications of veins (superficial/deep; pulmonary/systematic; large/small).

 

Brain

Brain

Is an organ which is often called ‘thinking machine’ due to the fact that it serves as the center of the nervous system. The brain is located inside your head close to the primary sensory organs. It is known that the brain is the most complex organ in a human body. The brain is consisted of two hemispheres and has some of main functions such as information processing, motor control, perception, arousal, motivation, learning and memory.

 

Throat

Throat

Is the anterior part of the neck. An important feature of the throat is the epiglottis which prevents inhalation of food or drink. The throat consists of various blood vessels, pharyngeal muscles, the windpipe and the esophagus. The main function of the throat is transferring food that goes down from your mouth to your stomach.

 

Liver

Liver

Is a vital organ of the digestive system. In its wide range of functions (including detoxification, protein synthesis and production of biochemical which are necessary for digestion), the liver is considered as the organ that cleans your blood. The liver consists of four lobes of different size and shape. Main physical properties of a human liver are its softness, pinkish-brown color and the triangular shape. In addition, the liver is the largest internal organ and the largest gland in a human body.

 

Stomach

Stomach

Is a muscular organ in a human body which plays an important role in the digestive tract. The stomach is involved in the second phase of the digestion, right after the chewing. It is located between the esophagus and the small intestine, in other words right in the center of a human body. Functions of a stomach include digestion, control of secretion and motility, it acts as nutrition sensor, it helps absorption and vitamin B12 absorption.

 

Kidneys

Kidneys

Are organs in a bean shape which serve several essential regulatory roles. They are essential in the urinary system as the organs that process all body waste. Also, they regulate the blood pressure, they serve the body as a natural filters of the blood and they remove water soluble wastes. In addition they are responsible for the reabsorption of water, glucose and amino acids.

 

Skeleton

Skeleton

Is the body part which acts as the supporting structure of an organism. The skeleton in a human body consists of fused and individual bones which are supported and supplemented by ligaments, muscles, cartilage and tendons. The main function of a skeleton is to support organs, anchors muscles and to protect organs such as the brain, lungs, heart and spinal cord.

 

Ribs

Ribs

are the long curved bones which with that kind of a structure form the cage. They surround the chest, enabling the lungs to expand. The main function of the ribs is the protection of the lungs, heart and other internal organs of the thorax. Every human being has 24 ribs or 12 pairs.

 

Bones

Bones

Make up the skeleton of a human body. There are about 206 different bones in your body. Their function is to support and protect the various organs of the body, to produce red and white blood cells, and to store minerals. Bone tissue is considered as a type of dense connective tissue. In a human body there is a variety of shapes and bones structures.

 

Skin

Skin

Is considered as the largest organ of a human body due to the fact that it covers almost the entire surface of a body. The skin is referred to as the soft outer covering. It interacts with the environment, and it plays a key role in protecting the body from external factors and excessive water loss. Other functions of the skin include insulation, temperature regulation, sensation and the production of vitamin D folates.

Teeth Anatomy

teeth anatomy

Teeth

Knowledge of the anatomy of teeth is indispensable not only in order to understand the pathological process, but also the possible therapies.
Teeth are found in the oral cavity, and their roots are inserted in the alveolar processes of the upper and lower jaw.
The permanent dentition of an adult is composed of 32 teeth, indicated with Arabic numbers from 1 to 8.
Teeth are identified as: INCISORS, CANINE TEETH, PREMOLARS AND MOLARS.
The tooth is composed of two parts: the CROWN and the ROOT.
Two different types of dental tissues cover these two structures.
The line of junction between the crown and the root is called the CEMENTUM-ENAMEL JUNCTION (CEJ – NECK). teeth
The CROWN is the part of the tooth that emerges from the bone and it is covered by Enamel.
The ROOT is the part of the tooth that is inserted into the bone and it is coated by Cementum.
In healthy conditions of the oral cavity it is not visible.
In clinical practice, the dental arches are usually distinguished in 4 quadrants, tracing two lines: a horizontal line that divides the upper arch from the lower one, and a vertical line that passes between the 2 central incisors of the upper and lower arch.
These lines thus delimit two upper quadrants (Right and Left) and the two lower quadrants (Right and Left) and this division makes it possible to indicate the precise position of teeth. Conventional abbreviations are used to indicate each tooth and its location.
The most commonly used system to effect annotations in clinical charts and to communicate among operators, is the following: the quadrants are numbered from 1 to 4, starting form the right upper jaw and proceeding in the clockwise direction.
The number of the tooth is combined with the quadrant in which the tooth is located.
Therefore, a number composed of two figures is assigned to each tooth: the first indicates the quadrant and the second indicates the single tooth.

 

Teeth issues

teeth smile anatomy
smile The hard part of the tooth is composed of three different calcified tissues:

  • DENTIN
  • ENAMEL
  • CEMENTUM

The DENTIN constitutes the principal part of the tooth and it is present in both the crown and the root.
The ENAMEL is the hardest of the calcified tissues and it forms a thick layer on the Dentin in the area that corresponds to the crown of the tooth.
The CEMENTUM coats the Dentin in the area that corresponds to the root of the tooth. The tooth encloses a hollow space within the Dentin called the PULP CAVITY.
This cavity has an opening at the apex of the root called the APICAL FORAMEN.
The walls of the pulp cavity are lined with ODONTOBLASTS, distributed in a single layer. They produce Dentin.
The remaining part of the pulp cavity is occupied by the dental pulp, which contains cells and numerous blood vessels and nerves that pass through the apical foramen; these are all necessary to keep the tooth alive.
DENTIN The Dentin is a calcified tissue, 72% of which is composed of inorganic salts, that are CRYSTALS OF HYDROXYAPATITE (Calcium Phosphate).
It is produced by the ODONTOBLASTS that, as already said, line the walls of the pulp cavity.
If a cross section of the Dentin is examined, the extensions of the Odontoblasts, called DENTINAL FIBERS or TOMES’ FIBERS, are visible. They extend towards the outside through many canaliculi called DENTINAL TUBULES.
The maximum production of Dentin performed by the Odontoblasts takes place during the development of the tooth; however this production never stops and continues, very slowly, even after the tooth has erupted.
The dental fibers are enveloped by nerves, therefore when the Dentin is exposed there is direct contact between the nerves and the external environment, and this causes pain.

ENAMEL 95-97% of the Enamel is composed of inorganic salts (Crystals of Hydroxyapatite). It is produced by cells called AMELOBLASTS which cease their activity when the tissue has been completely formed.
The structure of the Enamel is composed of PRISMS which extend from the external surface to the internal surface of the Enamel. An organic matrix is interposed between one prism and another (INTERPRISMATIC SUBSTANCE).
Each prism contains Crystals of Hydroxyapatite, that have a hexagonal section, and that are closely-packed and well aligned.
The Cementum-Enamel Junction at the neck of the tooth may have one of the three aspects described below:

  1. In 10% of the cases the Cementum and the Enamel are not in contact and a small portion of the Dentin remains exposed.
  2. In 30% of the cases the Cementum and the Enamel are in linear contact.
  3. In 60% of the cases the Cementum covers a small portion of the Enamel.

Abdominal And Stomach Bloating: Causes And Remedies

Abdominal And Stomach Bloating

Stomach bloating is a very common occurrence – all of us will experience it at some point in our lives. It is that feeling of “fullness” or “pressure” in the abdomen that can make you feel weighted down. Sometimes it is difficult to tell whether the cause of a flabby belly is abdominal fat or abdominal bloating, but it is important to be able to differentiate the two, because abdominal exercises will never reduce bloating.

What causes bloating?

The most common reason for abdominal bloating is gas trapped in the small intestine. Gas and abdominal pains, especially after meals, are an indication of this problem. Doctors believe that bloating is usually the result of an intestinal disorder such as IBS (irritable bowel syndrome), usually also associated with diarrhea, gas, abdominal pain, and changes in bowel habits.

Here are some of the common causes of stomach bloating:

  • Too much alcohol
  • Too little proteins in the diet – proteins speed up the rate the food goes through the system
  • Too much salt – even the smallest excess amount of sodium causes bloating
  • Fizzy drinks – the carbon dioxide (bubbles) creates gas which increases the volume of the stomach and slows down its emptying
  • Lactose intolerance – in this case the stomach cannot properly digest the lactose in dairy products, which leads to bloating
  • Pre-menstrual tension – in this case, the symptoms should disappear once menstruation starts
  • On-going stress
  • Certain medicines, including the contraceptive pill
  • Caffeine and smoking
  • Last but not least, there are certain foods that cause bloating. These are: beans, vegetables such as cabbage, Brussels, broccoli, onions; fruits such as apples, peaches and pears and some dietetic foods that contain artificial sweeteners such as sugar-free candies and gum. Fatty foods also delay the process of emptying the stomach causing abdominal bloating.

Stomach bloating after eating is the most common symptom of IBS. If this abdominal bloating lasts for more than a couple of days up to a week, you may be suffering from chronic stomach bloating. You may be surprised to find that if you avoid the causes presented above, your problem will be solved without any additional efforts. Below you can find some tips that will help you flatten your stomach if you suffer from IBS.

How can you get rid of bloating?

Drink plenty of water! Water offers great bloating relief; it helps with digestion encouraging your body to flush out toxins and emptying the stomach. You should drink at least 2 liters of plain water or herbal tea a day (fennel, cinnamon, dill and sage teas are just some of the herbal remedies for bloating).  Avoid fizzy drinks and drinks that have artificial sweeteners or caffeine.

Avoid the use of antibiotics. These antibiotics destroy the healthy bacteria in the digestive tract that are beneficial for the digestion of food. If you do have to take antibiotics, take B-complex vitamins with it, or drink yoghurt to protect these bacteria.

Avoid foods that are either too hot or too cold. Eating foods that have a temperature out of your comfort zone makes you unconsciously take in air. Very cold beverages and chewing gum can also make you swallow air that goes right to your stomach and bloats it.

Limit your salt and sugar intake: You may be taking in too much salt without even knowing it. Read the label of the products your buy and try to stick to low-sodium products. Also you may want to make healthier diet choices that will help your stomach look flatter (choose a fresh cucumber over a pickle or a baked potato over French fries).

Eat slowly! Take your time to chew or food! You’ll be helping your stomach break down the food faster and you’ll be swallowing less air.

No heavy meals at dinner time! A heavy meal, especially one that is not burnt for energy right away, encourages the buildup of acid which in turn leads to bloating.

Stomach bloating is a very common affection, usually caused by unhealthy eating habits. This problem can be corrected if you apply some healthy eating principles, and it usually doesn’t take a lot of effort to turn a flabby, bloated belly into a firm, flat tummy. However if bloating persists over a longer period of time, or gets worse in time, you should seek medical advice.