Biology 120 Chapter 8 Digestion

Chapter 8: Digestive System Presentation

By Roberto Ayala

Bite-Wing X-Ray

What is a bite-wing x-ray and why do I need one?• A bite-wing x-ray is one of many diagnostic imaging procedures that dentists can

use.

• There are two types of dental x-ray procedures.

1. Extraoral- X-rays are used to give a general image of dental health that are not necessarily related to any individual tooth. Most commonly used to diagnose disorders related to the temporomandibular joint (TMJ), which attaches the lower jaw to the skull. These disorders, called TMD, can cause symptoms ranging from mild discomfort to severe dental problems if left unchecked.

2. Intraoral- X-rays are used to give a very detailed image of an individual tooth or several teeth. They are used to detect and diagnose the severity of cavities, monitor root and gum health, and can determine the condition and alignment of dental fillings and implants. Bite-Wing X-Ray procedures fall into this category.

Bite-Wing X-Ray

Bite-Wing X-Ray Procedures Can Save Your Teeth!!!

• Considered a regular part of routine dental screening.

• Bite-Wing is a T-shaped x-ray film/sensor holder that is placed in the mouth, aligned with an x-ray gun, and held in place by clenching the teeth together.

•X-ray exposure is very minor, especially when high speed electronic sensors are used in place of traditional x-ray film. Some sensors are placed outside of the mouth, with the bite-wing used as an alignment device rather than a film/sensor holder.

•Can determine some dental issues long before they are visible to the eye, saving time and future patient discomfort.

From left to right. 1. A typical bite-wing x-ray identifying fillings and signs of tooth decay. 2. A X-Ray film bite-wing in place in the mouth. 3. Digital X-Ray sensors.

Extraction

Steve Martin as Orin Scrivello, DDS Little Shop of Horrors, 1986.Steve Martin as Orin Scrivello, DDS Little Shop of Horrors, 1986.Steve Martin as Orin Scrivello, DDS Little Shop of Horrors, 1986.

Extraction

Extraction is the surgical removal of a tooth that is severely damaged and/or detrimental in its placement within the mouth.

•Who does it and why?

• Performed by oral surgeons, also called maxillofacial surgeons, who are dentists that specialize in surgery of the mouth and jaw.

•Tooth removal is performed when decay is so severe, that no other treatment will stop the current infection or prevent its spread into surrounding teeth or the rest of the body.

•Wisdom teeth removal is an example where the extracted teeth may not be infected, but pose a threat to the health of surrounding teeth and gums.

Extraction

Procedures

• Can be performed under local or general anesthetic.

1. Local anesthetics typically given for simple extractions, typically an injection in conjunction with a sedative such as nitrous oxide. In many cases the patient can leave the office a short time after the procedure without any ill effects to their daily routine.

2. General anesthetic is given for complex procedures or multiple extractions. Typically the patient will need someone to take them home after the procedure is done. Other than rest, not much is to be expected from the patient.

Extraction

• Risks and Complications

1. Infection

• Bacteria in infected tooth can spread to the bloodstream.

• Antibiotic treatment recommended for high risk patients before procedures begin.

• Infection can occur in empty tooth socket. This risk varies on how well the patient is able to take care of the open wound after extraction.

2. Unintentional or Unavoidable Damage

• Procedure can temporarily or permanently damage surrounding teeth, gum, and bone structures.

• Paresthesia (numbness) is a risk for extractions performed in close proximity to nerves. If the nerve is permanently damaged, numbness may be permanent.

Right: Illustration of a wisdom tooth and a nerve in close proximity. The risk of paresthesia is high if this tooth is extracted.

Extraction

Recovery

•Depends on procedure and patient’s diligence on post procedural instructions.

•A cleaning routine will be given to the patient based on their needs. Typical instructions include:

•Cleaning/Replacing gauze at the site of the wound.

•Cleaning/Rinsing with salt water.

•Carefully brushing teeth while avoiding open wound and perhaps surrounding teeth.

•Avoiding sugary, sticky, and hard foods.

•Sleeping with the head and upper body elevated.

•The open wound from an extracted tooth can take anywhere from a few weeks to a year to fully heal.

Serum Bilirubin

Bilirubin: Is a yellow-brown substance found in bile and is a by-product of the reaction that breaks down hemoglobin from old red blood

cells.

Exists in the body in two forms.

1. Indirect bilirubin- formed from the heme during the breakdown of hemeglobin, travels throughout the bloodstream, insoluble in water. Returns to the liver for processing into direct bilirubin.

2. Direct bilirubin- liver-processed bilirubin released in bile. Can be stored in the gall bladder or goes directly into the small intestines. Water soluble, the breakdown of direct bilirubin occurs in the small intestines. By products give feces its brown-yellow color. Some by-products may be reabsorbed and recycled by the body. These recycled by-products ultimately end up in the urine.

Serum Bilirubin

• Normal, healthy humans have low levels of bilirubin in their blood stream. New born infants may have elevated levels of bilirubin and a jaundiced appearance for the first few days of life. This should decrease by the fifth day of life.

• Bilirubin can be measured by measuring the levels of direct bilirubin and total bilirubin in the blood. The level of indirect bilirubin is derived from these two measurements.

• The normal levels of bilirubin in the blood range from 0-0.3 mg/dL for direct bilirubin, 0.3-1.9 mg/dL for total bilirubin, and 0.2-0.8 mg/dL for indirect bilirubin.

• Signs of jaundice, a condition where the skin and whites of the eyes appear yellow, will start to occur at bilirubin levels higher than 2.5 mg/dL.

• Jaundice occurs when red blood cells are being broken down faster than the liver can process them. This can occurs due to a bile duct blockage or liver disease.

Serum Bilirubin

Test preparation and procedure.

1. When a serum bilirubin is performed by drawing blood from the patient. In adults this is usually done from a vein, in babies, the heel.

2. Patients should not eat for at least 4 hours before the test. However extended fasting can skew the results, so a test may need to be coordinated with a patient’s previous meal time.

3. Certain drugs and substances will effect the results of the test and should be avoided. Examples include steroids, aspirin, MAO inhibitors, codeine, some anti-biotics, birth control pills, vitamin C, and caffeine.

4. The blood sample is placed in a centrifuge which separates the blood serum from the cells. Bilirubin tests are performed on the serum. Test results typically are usually available within the same day.

5. Depending on the results, further tests may be performed to narrow down potential causes.

Serum Bilirubin

In General,

Elevated levels of bilirum indicate a potential for:

•Bile duct obstruction•Hepatitis •Cirrhosis•Hemolytic anemia•Intraheptic cholestasis (build up of bile in the liver).•Blood transfusion reactions.•Gallstones•Pancreatic disorders•Gallbladder disorders

Low levels of bilirubin are generally of no concern in normal, healthy individuals.

In an affected individual, this may indicate that medication or ingested substances may be interfering with test results.

Hematochezia

Hematochezia is the term referring to the presence of blood in the stool. Stool with this condition will be reddish in color or there may be blood still mixed in with the stool.

Paranoid? Worried? Should I be concerned?

There is always a small amount of blood in the stool. Most of the cannot it cannot be detected except for a detailed fecal occult stool test performed at a lab.

Excessive blood in the stool indicates the source of blood is from the lower GI tract. Since blood turns black as it travels through the digestive system, red blood in the stool indicates the source is in the latter part of the digestive tract, specifically, the large intestines and rectum.

Certain foods such as tomatoes and beets, can turn the stool red. This has been known to fool doctors and a chemical test has been developed that can rule out color changes from non-blood sources.

Hematochezia

Potential causes of hematochezia

•Anal Fissures

•Colon polyps or colon cancer

•Diverticulitis

•Hemorrhoids

•Inflammatory bowel syndromes

•Intestinal infection

•Vascular malformation

•Physical trauma or internal blockage due to foreign object

If bleeding is persistent, a physician will order a stool analysis to determine the source of bleeding.

Hematochezia

Stool analysis can help determine certain conditions that affect the digestive tract. Conditions include poor nutrition absorption, cancer, parasitic infection, etc.

In particular, a fecal occult blood test (FOBT) or a stool occult blood test, tests for hidden blood in the stool. In some cases they may be the only warning a person has in colorectal disease.

FOBT’s are only used to detect the presence of digestive disorder conditions, but never to diagnosis them. More invasive and conclusive tests are used for this purpose.

FOBT’s may be issued to a patient for at home collection or stool may be collected at a doctor’s office. Special instructions will be given to patients regarding diet, medications, and any time restrictions once the sample is collected.

If a test comes back positive, further tests will be performed to establish or rule out a diagnosis.

Sources:

http://www.ada.org/public/index.asp

http://www.webmed.com

http://www.nlm.nih.gov

http://www.nlm.nih.gov/MEDLINEPLUS/ency/article/003479.htm

http://www.nlm.nih.gov/medlineplus/ency/article/007008.htm

http://www.nlm.nih.gov/medlineplus/ency/article/003130.htm

http://www.webmd.com/oral-health/default.htm

http://www.webmd.com/digestive-disorders/bilirubin-15434

http://www.webmd.com/colorectal-cancer/fecal-occult-blood-test-fobt

Title Page Illustration

From: http://farm3.static.flickr.com/2314/1798065498_cc8c9f9a02_o.jpg