Infection control Biofilm What is it? Where would it be found in the dental surgery?
Infection control Biofilm is a naturally occurring slime producing bacteria and fungi which form into complex communities on wet surfaces Biofilms form in the water mains and on the walls of small bore plastic tubing in dental units
Infection control Contamination is the introduction of micro-organisms to sterile or non- sterile instruments, equipment or living things
infection control How would you describe the word “decontamination”
Infection control Decontamination is the processes required to make a re-useable dental instrument fit for use on another patient This will include cleaning, inspection for cleanliness, sterilisation or disinfection if sterilisation is not possible
Infection control Draw the symbol for single use items
The Heart The heart and the blood vessels are part of the ___________ system Blood _________ carry blood away from the heart Veins carry blood to the ______ from the rest of the body. The blood circulates, carrying oxygen and nutrients
anatomy The heart and the blood vessels are part of the CIRCULATORY system Blood VESSELS carry blood AWAY from the heart Veins carry blood TO the HEART from the rest of the body. The blood circulates, carrying oxygen and nutrients
anatomy There are _____ separate chambers in the heart Two _____ and two ______
anatomy There are FOUR separate chambers in the heart Two ATRIA and two VENTRICLES
anatomy How is oxygen transported around the body? What percentage of oxygen is in an expired breath?
anatomy Erythrocytes transport oxygen around the body (RED BLOOD CELLS)
anatomy Constituents of blood are: RED BLOOD CELLS, ALSO KNOWN AS…..? THROMBOCYTES, ALSO KNOWN AS ……? LEUCOCYTES ALSO KNOWN AS ………? PLASMA …………..associated with the defence mechanism, also known as ……..?
anatomy Constituents of blood are: RED BLOOD CELLS, ALSO KNOWN AS erythrocytes THROMBOCYTES, ALSO KNOWN AS blood platelets LEUCOCYTES ALSO KNOWN AS white blood cells defend against infection PLASMA - associated with the defence mechanism, also known as BLOOD CLOTTING AND ANTI BODY PRODUCTION
anatomy Expired air contains 16% oxygen and 4% carbon dioxide Inspired air contains 20% oxygen required for metabolism
anatomy The atria receive blood returning to the heart and the ventricles pump the blood out from the heart. Each of these chambers has a one way valve to ensure that the blood flow is always in one direction. With each beat, the right ventricle pumps de- oxygenated blood to the lungs while the left ventricle pumps oxygenated blood to the rest of the body. This happens approximately every 2.5 BILLION times in an average life time.
Oral diseases –periodontal disease This is the second most commonest disease affecting the oral cavity The first being dental caries “periodontal disease” covers a group of diseases which affect the supporting structures of the teeth THE PERIODONTUM
Oral diseases –periodontal disease The gingivae The periodontal ligament The alveolar bonePERIODONTITIS IS THE MAIN CAUSE OF TOOTH LOSS IN ADULTS
Oral diseases –periodontal disease THE SOLE CAUSE OF PERIODONTAL DISEASE IS THE PRESENCE AND ACCUMULATION OF DENTAL PLAQUE AROUND THE GINGIVAL MARGINS OF THE TEETH WHAT IS DENTAL PLAQUE?
Oral diseases –periodontal disease PLAQUE- is a combination of saliva and oral bacteria which form a sticky film on the surface of the tooth and allows food debris to become incorporated into its structure It tends to form initially at the gingival margin because this area is not self- cleansed by salivary flow or by the tongue and soft tissue movements
Oral diseases –periodontal disease Bacteria within plaque use food debris to nourish themselves and allow the bacteria to colonise and grow Bacteria produce TOXIC BY-PRODUCTS as they digest food These irritate the gingivae and cause inflammation (CHRONIC GINGIVITIS)
Oral diseases –periodontal disease The inflamed gingivae become red and swell to form a FALSE POCKET around the neck of the tooth False pockets allow more plaque to develop as self cleansing becomes impossible Plaque now extends below the gingival margin The continued action of saliva on plaque allows inorganic ions to be incorporated into the plaque structure CALCULUS is now formed
Oral diseases –periodontal disease Calculus formation above the gum margin is called SUPRA GINGIVAL CALCULUS it is yellow in colour Calculus formation below the gum margin is called SUB GINGIVAL CALCULUS it is brow/black in colour due to the blood pigments Its surface is rough allowing more plaque to form over it and irritating the gingivae further
Oral diseases –periodontal disease The abrasion of the calculus and the chemical action of the toxins cause PAINLESS micro-ulceration of the gingivae, leading to bleeding to touch or dental probing The visible appearance and bleeding on probing of the gingivae are the classic diagnostic signs of CHRONIC GINGIVITIS
Events leading to periodontitis Non-treatment of chronic gingivitis allows TOXINS to build up and eventually enter the underlying gingival tissues through the MICRO-ULCERATION areas TOXINS destroy the PERIODONTAL LIGAMENT TRUE POCKETS form The attachment is lost from the neck of the tooth and down the root of the tooth Further plaque MINERALISES causing irritation and more toxin infiltration The tooth is now mobile as the alveolar bone is destroyed leading to tooth loss.
Removable Prosthetics Why do we provide patients with removable prosthetics?
Removable Prosthetics Prevents masticatory forces on remaining teeth Prevent overeruption of opposing teeth Prevents tilting of adjacent teeth Prevents soft tissue trauma due to mastication Prevents digestion problems Allows adequate mastication Provides good aesthetics especially anterior teeth
Removable Prosthetics What are the retention factors in removable prosthetics?
Removable Prosthetics Saliva – a film of saliva developing between the denture and the patients soft tissues A post dam along the back border of the denture An accurate design and fit of denture to allow the film to develop adequately Use of natural undercuts such as the alveolar ridges or natural teeth Use of clasps around natural teeth to increase retention
Removable Prostheticsdenture construction 1st imps – taken in either edendtulous stock tray or dentate stock tray using alginate Lab – models cast in plaster, special trays made from shellac, wax occlusal rims are made 2nd appt – final imps in special trays using alginate, bite registration Lab – final models cast, articulator used to show movement then construct wax try ins shade chosen by dental team and patient
Removable Prostheticsdenture construction 3rd Appt – try in of accuracy of occlusion, shade and fit. Any adjustments can be made at this stage, major adjustment would require a re-try Lab – try in and models are flasked, wax removed with boiling water to leave the teeth in position, filled with acrylic, clasps added at this point if necessary, clean and polish dent for fit Fit – inserted & checked for comfort, accuracry and retention & appearance. Instructions given on their wear, final adjustments made with straight handpiece and acrylic trimming bur, articulating paper, miller forceps
List the information requiredfor the dental technician toconstruct a removableprosthetic at each stage
Chrome cobalt partial dentures Used as the base of the denture Complicated design & longer to construct More expensive Much thinner palatal coverage is possible allows more tolerance for pts with gag reflex Less likely to break Skeleton design gives minimal coverage hygienic
Fixed prosthetics Why would we provide a patient with a crown?
Fixed prosthetics Heavily restored tooth Repeated failure of restoration Root filled tooth tends to become brittle Aesthetics Shape change to make a more retentive abutment tooth for a removable prosthetic
Fixed prostheticsBridgework:Name the variety of bridges available for patients giving a reason for providing a patient with a specific type
State the reasons for providinga temporary crown
State the reasons for providinga temporary crown Maintain space Prevent over eruption Prevent sensitivity Prevent food packing Prevent gingival overgrowth Aesthetics Prevent damage to prep
radiography Why are x-rays taken in dentistry?
RadiographyX-rays are taken to: Detect caries Detect supernumary Detect bone level Diagnose cysts, tumours, jaw Detect overhangs/perforati fractures ons Orthodontic Determine tooth treatment planning structure prior to xtn Aid in endodontic tx
Name the components of anintra-oral film packet
Name the components of anintra-oral film packet Front of plastic envelope Black paper X-ray film Black paper Lead foil Back of plastic envelope
Intra-oral film A celluloid film coated with light-sensitive bromide salts in an emulsion This is surrounded in black paper to protect it from unwanted light Enclosed in a waterproof envelope one side of the film is a lead foil which prevents the emulsion coat being exposed twice by absorbing scatter during the exposure When exposed the crystals form a hidden image The film must be processed to develop the image
In pairs discuss some faults whichmay occur during processing What temperature should the chemicals reach to ensure clarity of the film? For manual development of x-rays draw the tanks and label them
Temp = 18-22 degrees Celsius Faults: Too dark – overdeveloping Faint image – under Fogged film – developing, temp too low or Daylight exposure time too short or dev too Blank film – placement in weak fixer before developer Blank spot – contamination Partly blank film – not fully with splashes of fixer immersed in developer Brown or green stains – Scratches or fingerprints – incomplete fix bad handling Black line across film – being folded during process
In pairs: Discuss the Discuss the different types of different types of LA available in the syringes, needles dental surgery and injection types Discuss the nerves Name the reasons anaesthetised to for using the carry out treatment different types througout the mouth
In groups Compile 15 questions and answers on specific topics we have covered previously When completed, deliver to the rest of the class to answer