1- surgical instruments and materials

What are the 2 types of instruments?

Simple- manual instruments directly activated by surgeon

Complex- high tech, activated by mechanism

Give examples of simple vs complex instruments

Forceps, needle holders

Electric scalpel, turbine

What are the parts of a simple surgical instrument?

Active area

Intermediate area, neck or stem

Passive area or handle

What instruments are used for local anaesthesia?

Metal cartridge syringe 

Disposable plastic syringe 

Yutil metal syringe- doesn’t allow aspirating, high pressure, banned

Intraligamentary metal syringe 

What are the advantages of a metal cartridge syringe?

Allows aspirating

Needles and cartridges easily changed

Easy to clean and sterilise

Controllable manual infiltration

What are characteristics of disposable needles for cartridges syringes?

Caliber- smaller number- thicker needle

Length- 25-27-30-38-40

Bevelled needle tip- short bevel of 45 degrees better than long- 5-7- produces less trauma 

What instruments are used to facilitate visualisation and its subtypes?

Retractors maintain the flap- 

Farabeuf

Minnesota

Tongue depressor

Mouth prop 

What’s this and what is it used for?

Farabeuf

Two blades- diff width and length 

Retract lips and flap 

What’s this, used where?

Minnesota

Retract flaps

Any part of oral region

What’s this, used for?

Langenbeck

Retract, retain, protect flaps and cheeks 

What’s this?

Austin 

What’s this?

Middeldorf

What’s this?

Tongue depressor- could also use spoon 

What’s this?

Branemark retractor 

What are scalpels?

Sharp- for incisions 

Handle no 3 

Blades are…

Disposable, removable, individual sterilised packages

How can you tell the difference between blades used for scalpels?

10, 11, 12, 15

10, 15- curved

11- straight 

12- hooked 

What are scissors and how does the appearance help?

Cutting instruments apply principles of 1st order lever 

Blunt ends and medium sized curves for dissection of tissues

What are periosteal elevators used for?

Reflect and retract flap 

Full thickness mucoperiosteal flap- detach buccal or palatal mucosa and periosteum from underlying bone 

Partial thickness flap- leave underlying periosteum and bone 

What’s this?

Obwegeser

What’s this?

Howarth

What’s this?

Molt

What’s this?

Willinger- elevator 

What’s this?

Freer- elevator

What’s this?

Pritchard- elevator 

What’s this?

Buser- elevator

What are curettes?

Small scoop design- debride soft tissues

Straight/angles, varying length and concavity shape

What type of instrument and its name?

Volkmann- more scooped

What type of instrument and its name?

Lucas- flatter

What are these and what are they used for?

Rongeur forceps (bone nibblers)

Remove bony tips from sharp alveolar edges- for hard tissues

Sharp concave ends

What are these and what are they used for?

Bone files- have 2 active areas with diff inclination and orientation

File and smooth sharp or compressed bone edges

What are these and the types?

Chisels- straight with single, double or half round bevel 

What are these?

Field tweezers or pincers 

What are these?

Dissecting tweezers- long/short, with/out teeth, thick/thin

What are these, characteristics and what is it used for?

Hemostatic tweezers- mosquito

straight/curved, blunt end with/out teeth

used to hold continuous pressure and clamp blood vessels  

What are these?

Forcipression tweezers- Allis- holds tissues together 

What’s this?

Needle holder- forcipression tweezer to hold suture needles 

What are the types of engines of a rotary instrument and its characteristics?

Conventional 

Electric or compressed air- low speed- up to 40,000rpm

Turbine- high speed- 300,000-400,000rpm- risk of bone necrosis and subcutaneous emphysema 

How does irrigation improve the use of a surgical handpiece?

Irrigated with water to preserve vitality of tissues without overheating

Keeps site clear of debris

Can see consistency of tissue

What can burs be made of and give two types?

Tungsten carbide- round, different calibers, for osteotomy and ostectomy

Steel- thick to smooth bone edges

Lindemann burs- elongated for hard to reach areas

Fissure burs- tapered or straight

How does an electric scalpel work, when is it used?

High freq alternating current into electrode- active and passive

To dissect tissues, electrocoagulation, desiccate

Advs of electric scalpel

Sterile accurate incision, high speed

Doesn’t compress or cause tissues to bleed

Good healing

Multiple uses

Disadvs of electric scalpel

Unpleasant smell and smoke

Can’t use in pacemaker carriers 

Risk of explosion 

What does laser stand for?

Light amplification by stimulation emission of radiation

What are the uses of low vs high power lasers?

Analgesia and anti inflammatory

Incisions, vaporise or ablate hard tissues

What are the characteristics of lasers?

Amplification- aggregating effect 

Monochromatic- uniform wavelength 

Unidirectional 

Coherence 

What are the features of a suture needle?

Straight/curved

Triangular or cyclindrical crossection tip

Atraumatic

Diff length and radius- 1/2, 1/4, 3/8, 5/8 

What are the diff types of suture thread?

Absorbable- synthetic, natural 

Non absorbable- metallic, synthetic, natural

What are the characteristics of 3/0 black braided silk?

Easy handling and knot tying (resistant to unravelling)

Foreign body reaction, retention of bacterial plaque, expansion due to liquid absorption

What are the 4 types of hemostatics for hemorrhage control?

Hemostatic medications- with compresses/gauze 

Sponges- resorbable filler material 

Bone wax

Surgical cements 

What are the methods for drainage?

Tubes (penrose)- when there’s an extraoral route of bone, skin or for large cystic lesions

Gauze (capillarity)

Glove finger

Puncture

What are materials for bone regeneration/substitution? (3)

Regeneration membranes (barrier for bone growth instead of ct)

Artificial bone substitutes

Autologous bone

What is the disinfection?

Destroys pathogenic organisms vegetative or non-sporulant state- Chemical (includes ultrasonic tanks)

What is sterilization?

Elimination of all microorganisms including sporulated forms

Chemical or physical

What is the preferred method of sterilization and why?

Pressurised water vapour (in autoclave)-

Destroys all microorganisms and spores

Doesn’t deteriorate instruments

Corrosion avoided with 0.1% cyclohexylamine

What are the disadvantages of dry heat like flame treatments and hot air vs wet heat like boiling?

harms instruments

requires long time for bactericidal effect

Sensitive to water hardness and altitude, ca precipitates in instruments, doesn’t destroy spores or microorganisms 

What is the correct procedure for instruments sterilisation? (7)

Wash and brush

If highly contaminated, bath of 2% glutaraldehyde, 0.5% chlorexidine with 70% alcohol

Disassemble multi component instruments

Ultrasonic treatment of surgical instruments and burs

Dry and place in sealable bags

Put in autoclave trays

Use indicator strips to confirm correct sterilization cycle completed

What are the uses of antiseptic liquids?

Disinfect of skin or mucosa

Rinse oral cavity to reduce no of microorganisms

Local treatment of oral lesions

Treat of clinical surfaces

What is the most used antiseptic liquids?

0.5% chlorhexidine solution with 70% alcohol

2% glutaraldehyde solution

30 mins immersion- disinfects

10h immersion- sterilises

What are the features of formaldehyde gas as an antiseptic?

Good bactericide

Slow 48h action

formalin or trioxymethylene tablets

What are the features of ethylene oxide gas as an antiseptic?

Great efficiency in 2-6hrs

Flammable in contact with air

Instruments must be aired for 48hrs

What are the features of non-saturated chemical steam as antiseptic?

Effective in 10 minutes

Avoids corrosion and loss of cutting edges in sharp

instruments, turbines and handpieces

How is gamma vs beta vs UV radiation for sterilization?

Highly effective, need to protect personnel, expensive, cold method

less, strict rules, for slightly dense material

Least effect- germicide, used in operating rooms