#6 What I Learned Today

Essentials of Clinical Practice

We continued with discussing infection control, focusing mainly on setting up and cleaning a dental clinic, and sterilizing dental equipment. The school has strict policies in maintaining a clean clinic environment; almost all surfaces which are in direct contact with either the patient or the dental practitioner is cleaned prior to appointment and covered with a protective plastic covering. Regulated waste is disposed up through proper disposal procedures.

Dental unit waterlines are often a primary reservoir for bacterial biofilms, and thus lines need to be cleaned often. Another option is to have units that have detachable water bottles which can be filled and clean at the beginning and end of each day. Water being used in most dental treatments must meet regulatory standards set forth for drinking water, which is a heterotrophic bacterial count of less than 500 CFU/mL. In case of a boil water advisory, water must either be boiled, or bought in bottles. Lines should be ran for a period of time afterward once the advisory has been lifted.

All reusable instruments must be sterilized between uses. There are a number of different sterilizing techniques, including steam, dry heat, and flash sterilization. Each type of sterilization has its own procedures (duration, temperature, whether packaging can be used) to be followed.

Gross Anatomy I

Today we began our look at the thoracic cavity; specifically the heart and the circulatory system. Both the lungs and the heart have serous membranes to minimize amount of friction occurring to the organs. There are two separate linings, with serous fluid in between them. The heart layers are the parietal pericardium (lines the pericardial cavity) and the visceral pericardium (lines the heart). Fibrous pericardium attach the heart to the diaphragm (actually moves the heart when you breath!).

The heart has four chamber: left & right atrium, and left & right ventricle. Deoxygenated blood flows into the right atrium from three places: the superior and inferior vena cava, and the coronary sinus. It passes through tricuspid valve and into the right ventricle, where the blood is pumped through the pulmonary semilunar valve to the lungs. It is oxygenated, and returned to the left atrium. From there, it passes through the bicuspid (mitral) valve, where it pumped from the left ventricle through the aortic semilunar valve and out to the circulatory system.

The heart starts by supplying oxygenated blood to itself first, through the left coronary artery and the right coronary artery. These arteries are special in that the blood is not pumped through them, but rather passively flows through between heart beats. The two arteries split into a number of different arteries, including the anterior and posterior interventicular arteries, and the marginal artery. The anterior and posterior interventicular arteries meet up at anastomoses.

Gross Anatomy I Lab

Lab was pretty simple today. We started by cutting open the thoracic cavity of our cadaver. The pectoralis major and minor muscles were isolated, along with the medial and lateral thoracic nerves (which innervate the pecs). Also, we managed to find the cephalic vein, which is situated between the deltoid muscle and the pec major.

We finished off by cracking open the ribs on both sides, and the anterior part of the sternum in order to gain access to the lungs and heart, which we will be dissecting next week.