CAD - Intro to minor surgical technique Flashcards
1
Q
Define oral surgery
A
The diagnosis and management of pathology of the mouth and jaws that requires surgical intervention.
2
Q
Which patients are treated in oral surgery?
A
The treatment of children, adolescents and adults and the management of dentally anxious and medically complex patients.
3
Q
List the procedures that may be carried out by an oral surgeon.
A
- Extractions
- 3rd molar extractions
- ST biopsies, histology
- Implants
- Bone grafts
- Surgical endodontics
- Removal of cysts
- TMJ & facial pain
- Sinus problems
- OAC & OAF
- Impacted canines
- Sedation, Midazolam, Nitrousoxide
- CBCT
4
Q
Following diagnosis, what are the next two steps?
A
Determine complexity of tx: straight forward? / Advanced? / Complex?
Formulate a tx plan that involves the patient
5
Q
Trauma / insult to tissues caused by an extraction should lead to ______ over 6-8 weeks.
A
Healing
6
Q
What factors cause physical tissue damage?
A
- Compromised blood flow
- Crushing
- Desiccation
- Incision
- Irradiation
- Overcooling
- Overheating (removing bone with handpiece that is cooled with water)
7
Q
What factors cause chemical tissue damage?
A
- Agents with unphysiologic pH
- Agents with unphysiologic tonicity
- Proteases
- Vasoconstrictors – e.g. adrenaline in LA
- Thrombogenic Agents (blood clotting)
8
Q
What are the four stages of acute wound healing after an extraction?
A
- Haemostasis (seconds to hours)
- Inflammatory phase (hours to days)
- Proliferative phase (days to week)
- Remodelling (week to months)
9
Q
What happens during haemostasis?
A
- Vasoconstriction
- Platelet aggregation
- Leucocyte migration
10
Q
What happens in early and late inflammatory phase of acute wound healing?
A
Early: neutrophil chemoattraction
Late: macrophages carry out phagocytosis and removal of foreign body/bacteria
11
Q
What happens during the proliferative phase?
- Acute wound healing
A
- Fibroblasts proliferate
- Collagen synthesis
- Extra-cellular matrix reorganisation
- Angiogenesis
- Granulation tissue formation
- Epithelialization
12
Q
What happens during the remodelling?
A
Remodelling:
* Epithelialization (repair of wounded area by epithelial cells).
* Extra-cellular matrix remodelling
* Increase in tensile strength of the wound
13
Q
Describe what happens in week 1 of a healing tooth socket.
A
WBCs remove bacteria
Breakdown debris e.g bone fragments
Fibroplasia begins (process of granulation tissue formation by fibroblast proliferation)
Ingrowth of fibroblasts & capillaries
Epithelium migrates down socket wall
Osteoclasts accumulate along crestal bone – bone degradation
14
Q
What happens in week 2 of a healing tooth socket?
A
- Granulation tissue fills socket (new connective tissue & microscopic blood vessels)
- Osteoid deposition along alveolar bone lining socket (unmineralized bone tissue)
- Smaller sockets – fully intact epithelium
15
Q
What happens in week 3-4 of a healing tooth socket?
A
o Cortical bone resorbs from the crest and walls
o New trabecular bone laid down
o At 4-6 months: cortical bone lining fully resorbed
o Epithelium moves to crest
16
Q
Difference between cortical bone and trabecular bone?
A
Cortical bone – dense outer surface of bone that forms a protective layer around the interval cavity. High resistance to bending and torsion.
Trabecular bone- Hierarchical- made of 20% bone and the rest is marrow and fat. It is spongy and porous.
17
Q
_______ ‘intention’ is where the edges of a wound (no tissue loss) are placed and stabilised in the same anatomical position prior to injury and allowed to heal.
A
Primary intention.
18
Q
_______ ‘intention’ implies a ‘gap’ is left between edges of incision / laceration. – wound is left open without stitches to heal by itself. Closes up naturally.
A
Secondary intention.
19
Q
What happens during secondary intention of wound healing?
A
- Tissue loss has occurred around the wound edges
- Significant amount of epithelial migration, collagen deposition etc
- Slower, heals with a scar [e.g. tooth socket, poorly reduced #, deep ulcers]
20
Q
What are osteogenic cells (stem cell) / osteoprogenitor cells?
A
- Stem cells that play a role in bone repair and growth.
- Precursor to osteocytes and osteoblasts.
- Reside in bone marrow.
21
Q
What is an osteoblast?
A
- Cells that form the bone matrix
- Bone healing
- Found in the periosteum & endosteum
- Pluripotential mesenchymal cells are able to differentiate into osteoblasts
22
Q
What is an osteocyte?
A
- Cell that maintains bone tissue
- Derived from osteoblasts
23
Q
_________: A bone cell that resorbs bone.
A
Osteoclast
24
Q
After tissue injury, the inflammatory phase occurs within 3-5 days. Which two phases is this made of?
A
Vascular and cellular phase occurs.
25
What happens during the vascular phase of inflammation in a healing socket?
- Initial vasoconstriction of disrupted vessels slows blood flow into injured area promotes coagulation.
- Histamine, prostaglandins and WBCs are released leading to vasodilation which opens small spaces between endothelial cells. Plasma leaks, leukocytes migrate and fibrin exudate forms leading to OEDEMA.
26
Describe the cellular phase of inflammation in a healing socket.
- Activation of complement and neutrophils leads to redness (rubor), swelling (tumor), heat (calor) and pain (dolor)
27
What happens in the proliferative phase?
- Fibrin strands form the structure for fibroblasts to lay the ground substance and tropocollagen
- Collagen and capillaries are formed.
- It takes 2-3 weeks for wound strength to develop
28
What happens in the final stage of wound healing?
Final stage – Remodelling.
Continues indefinitely
Wound maturation & contraction
Previous collagen fibres are destroyed – replaced by new collagen - orientated better. Wound strength slowly increases.
Vascularity decreases (as does erythema)
Redness settles
29
Which 6 factors influence a healing socket?
Foreign material – bacteria, dirt, suture material that gets infected. Antigenic – chronic inflammatory reaction.
Necrotic tissue – barrier to ingrowth of reparative cells. Prolonged inflammatory stage with WBCs. Acts as a nutrient for bacteria e.g. haematoma.
Ischaemia – good vs poor blood flow
Wound tension- sutures too tight causing tension = ischaemia. Healing with excess scar formation and wound contraction.
Age and MH of pt
Operator technique
30
Expand on how ischaemia affects healing.
- Reduction in blood supply affects healing = Further tissue necrosis
- Reduction in delivery of: wound antibodies, WBCs, Antibiotics, Nutrients / Oxygen to ensure healing
31
What are the possible causes of ischaemia in the healing socket?
o Sutures
o Poor flap design
o Excessive external pressure
o Internal pressure
o Systemic BP issues
o Peripheral vascular disease (narrowing, blockage or spasm in blood vessels)
o Anaemia (reduced RBC or Hb)
32
How can age, MH, drug history, BMI, SH, anxiety / cooperation affect healing?
Age – complications more likely with older pts e.g. mand. third molars
Medical History – Ischemic Heart Disease, CVA, Diabetes Mellitus, neoplasia.
Drug History – anticoagulants, steroids (long term = poor healing), bisphosphonates, immunosuppressants, Antibiotic prophylaxis for cardio problems.
BMI – airway & access – higher BMI = smaller mouth, short fat neck. Additional medical complications.
Social History - smoking - dry socket.
Anxiety / Co-operation - stress
33
Which operator factors influence healing after xla?
- Competence
- Experience
- Environment
- Assistance
34
What are the surgical factors that affect healing after xla?
o Diagnosis
o Access
o Imaging
o Pathology
o Bone
o Surgical site (e.g tooth)
o Mouth opening
35
What are the key EOE structures to check in oral surgery?
- Cervical lymphadenopathy
- Mouth opening
- TMJ
- Facial asymmetry
- Facial swelling
- Other significant findings
- VII (motor: look up and wrinkle forhead - should be symmetrical. Close eyes and don't allow pt to open them. Ask pt to smile etc)
- V nerves - sensory: light touch to forhead, cheek and chin whilst pts eyes are closed. Ask pt to answer if they feel these).
36
What are the key IOE structures to check in oral surgery?
Soft tissues (tongue, FOM, buccal mucosa etc)
Hard tissues – dentition
Focus on area in question
Special tests - rads, sensibility, tooth sleuth etc
37
What does the surgical sieve VITAMIN C DEF stand for?
- reaching a diagnosis
V- vascular
I- infective/inflammatory
T- trauma
A- autoimmune
M- metabolic
I- iatrogenic
N- neoplastic
C- congenital
D- degenerative
E- endocrine / environment
F- Functional
38
How can we reach the correct diagnosis in oral surgery?
Use the surgical sieve: VITAMIN C D E F for a differential diagnosis.
Then rule out: most likely to not likely.
Carry out investigations: radiographs, special tests.
39
How do we know if a radiograph is acceptable?
- oral surgery
- Radiographs of diagnostic quality
- Contrast and density
- Region of interest clearly visible
- Surrounding tissue
- No distortion
40
How do we analyse radiographs for anatomy?
Systematic process:
Normal Anatomy -> Variation of normal anatomy -> Actual pathology
Abnormality detected: S T O P
check the Site (tissues present), Translucency (radio- opaque/lucent), Outline (margins), Previous imaging for comparison.
* Size and shape
41
What are the red flags that can be detected on a radiograph indicating abnormality?
Loss of symmetry
Distorted anatomy – displaced teeth
Bone erosions – (borders)
Teeth floating in ‘air'
42
What are the key operator practices before xla?
- Adequate access - mouth opening: 35-55mm / 3 fingers, and surgical access.
- Lighting
- Surgical field free of excess blood / fluid -> suction & assistant
- PPE: standard, full, enhanced.
43
What pre-opertative factors may improve pts outcomes?
- Analgesia – help with pain. Analgesic ladder – mild pain: Ibuprofen, paracetamol [not all pts can take these].
- Antibiotics
- M.wash - Chx (pre-op rinse to reduce microbial load), NaCl (best option post op)
44
When is paracetamol contraindicated for certain patients?
Acute liver failure, liver problems, allergies
45
When is ibuprofen contraindicated for certain patients?
*children under 17
*stomach ulcers, perforation in stomach, bleeding of stomach
* Pts on anticoagulants
*Severe heart / kidney / liver failure. Stroke.
* High BP that is uncontrolled
* Asthma, hay fever, allergies
*Crohns disease, ulcerative colitis
* Chickenpox, shingles
46
What are the anaesthetic options in oral surgery?
1. LA
2. LA + concious sedation (inhalation/ IV)
3. LA + GA
47
List the ideal properties of LA.
Rapid onset, reversible
Specific action
Non-irritant
No permanent damage
No system toxicity
High therapeutic ratio
Chemically stable
Sterilisable
Can use with other agents
Hypoallergenic
Non-addictive
48
What are esters and amides? - LA
- Chemical structures of LA
Amides:
– lidocaine (* Rapid onset. Medium duration 1.5-2.5 hrs), xylocaine, , bupivacaine, articaine (longest duration)
- Prilocaine – less potent than lidocaine – poor onset. Without epinephrine. Short duration.
- Mepivacaine- without epinephrine. Lasts the shortest duration – 30 mins.
49
Why is a vasoconstrictor used in LA?
* Increase speed of onset
* Extend duration of LA
* Increased depth of anaesthesia
* Reduction of intra-operative haemorrhage
50
What is adrenaline?
- LA
* Analogue of naturally occurring peptide vasopressin
* Vascular smooth muscle contraction
* Coronary artery vasoconstriction
* Oxytocic effects on uterus
51
What is the dose of lidocaine, the maximum dose and its’ contents?
2% Lidocaine with 1:80,000 adrenaline- Available as topical spray, gel, ointment and injection form.
Maximum dose: 4.4mg/kg. Ceiling dose: 300mg (giving more doesn’t increase its effect)
Contents: 44mg lidocaine. 27.5 micro g adrenaline. NaCl, Sodium metabisulfite, NaOH, HCl, H2O
52
What is the dose of articaine, the maximum dose and its’ contents?
% Articaine with 1:100,000 adrenaline- injection.
* Maximum dose: 7mg/kg >4 yrs old.
* Contents: 88mg articaine. 22 micro g adrenaline. NaCl, Sodium metabisulfite, NaOH, H2O
53
What are the indications for pre / peri operative antibiotics?
- To prevent post-op infection
- Compromised host
- Before placing a foreign object/material e.g. implants / bone grafts
54
What are the indications for antibiotics if infection is present?
* Acute local infection unable to remove cause
* Rapidly spreading infection – systemic involvement (*fever, lymphadenopathy)
* Persistent recurrent infection - unknown cause
55
Specific regimes for antibiotics are controversial. When would we prescribe?
o Pt by pt basis – depends on MH, SH etc
o AB prophylaxis – infective carditis – consult cardiologist.
o Procedure dependent
56
Which patient groups should we consider antibiotics for?
Disease: Diabetes mellitus – poor healing, alcohol dependents – poor healing, renal failure, malignancy.
Pts on medications: steroids, immunosuppressants/ chemo, transplant, radiation therapy.
57
What are the indications for oral surgery?
* Remove retained roots
* Complete a procedure (e.g. crown fracture during xla requiring a raised flap)
* Access pathology e.g. cyst in jaw
* Impacted tooth (Mand Third Molar, canine etc)
* Tissue sample (biopsy)
* Surgical endodontics
58
What are the key principles in oral surgery?
* Sufficient access
* Preserve vital structures – IAN in mandible, greater palatine foramen –(artery and venous supply to the palate), incisive foramen in maxilla.
* Incisions on sound bone when raising flaps
* Protect ST
* Minimise tissue damage
* Preserve blood supply
* Closure on sound bone (dead space breaks down and doesn’t heal)
59
What route does the ID nerve follow in the mandible?
1. Inserts into lingula on lingual side of mandible
2. Runs through mandible; travelling buccally to exit the mental foramen to supply the anterior dentition and ST.
*The lingula can sit high in patients so need to be careful not to cause permanent damage.
60
What is a flap in oral surgery?
o A flap is a section of soft tissue which is outlined by a surgical incision
o Full-thickness mucoperiosteal flap– lifting the periosteum, submucosa and surface mucosa off the bone.
61
What are the adv of raising a flap?
o Carries its’ own blood supply
o Allows access to underlying tissues
o Can be replaced to its’ original position
o Can be maintained with sutures
62
What are the key principles of raising a flap?
- Visualisation of area
- Instrumentation
- Retraction to protect ST
- Enough flap to retract without tension
- Sharp incisions heal better than torn
63
Which careful operator factors are utilised when raising a flap?
- Firm controlled movements
- Careful ST handling – avoid crushing / tearing
- Ensure cooling when using rotary motors
- Debridement (bone dust, tooth fragments, restorative materials, sharp bone)
- Follow principles of suturing– primary intention healing.
64
What are the different types of flaps?
* 1 sided flap -around cervical margins of teeth.
* 2 sided flap (2 different sides) –may sacrifice long buccal nerve (but innovation minimal)
* 3 sided flap (mesial relieving incision – difficult to suture and often breaks down).
*need a broad base of flap for good blood supply.
65
What are the steps in wound debridement?
* Check for any debris
* Smooth off sharp bone margins
* Irrigate gently with saline to ensure a clean wound prior to closure
66
How is wound closure carried out?
Fix the free tissue to the fixed tissue.
Key landmarks first e.g. papillae
Don’t over tighten sutures.
67
What are the clinical stages of raising a flap?
1. Give adequate LA
2. Create incision using number 3 handle and 15/15C blade- small and thin to get around cervical margins. (pen grip)
3. Can use a Mitchells Trimmer to raise a flap (two ends – one sharp, one smooth).
4. Use Howarth’s periosteal elevator to retract flap.
Or Rake retractor (can tear on base of flap) or Minnesota Retractor is used to keep the flap raised.
5. Protect ST: variety of options: Optragate, Lack’s tongue depressors, mirror, Kilner cheek retractor / C-shaped retractor.
6. Suture using needle holders and toothed forceps to hold ST.
* Wound closure by primary intention
68
What happens if an air motor is used to section teeth / remove bone?
Air that comes out of the bur is driven down to the bur along with the water jets.
If air is fired into ST / bone, this can result in surgical emphysema. Feels like eggshell crackling / popping plastic.
The air can travel through ST in head and neck and spread into mediastinum and around pericardium. Pts end up in critical care.
69
What devices should be used to section teeth / remove bone?
Surgical motor (U.K) – separate unit powered by electricity. Rotary. Saline irrigates onto bur. 40,000 RPM, 1:1 torque. Straight handpiece. Fissure bur and round bur available.
Reverse air exhaust (U.S) – air comes out of back end of handpiece.
70
What is the purpose of suturing?
To hold the tissues in place to permit healing by primary intention and to control bleeding.
71
What are the benefits of suturing?
o Achieve haemostasis
o Approximate ST after surgical procedure
o Skin lacerations
o Ligation of blood vessels.
72
What are the ideal suture material properties?
* Adequate tensile strength
* Functional strength
* Non-capillary/wicking
* Non-reactive
* Flexible/easy to handle
* Ability to ‘knot’
* Sterilisable
* Smooth
* Resorbable
73
What are the basic suture techniques?
Simple interrupted
Continuous suture (Long wounds - but if one end comes undone, the whole suture fails.
Vertical and horizontal mattress
Figure of 8 – e.g. pts on anticoagulants: material placed into socket & kept in place using figure of 8 suture.
74
What type of suture materials are used in oral surgery LDI?
Resorbable - resorbed or digested by the body cells and tissue fluids in which they are embedded during and after the healing process e.g Synthetic Vicryl - absorbed by hydrolysis.
75
What are non-resorbable suture materials?
Suture materials that cannot be resorbed by the body or cells or fluid. They are removed after healing is completed. e.g nylon
76
What are the different properties of sutures available?
Natural / Synthetic
Absorbable / non-absorbable: hydrolysis (Vicryl) or foreign body reaction with enzymatic involvement e.g. gut.
Mono-filament (one thread, smooth) or Multi -filament (twisting /braided many multiple threads)
77
What are the properties of the Vicryl Rapide suture?
- wound support for 10 days (50% at 5 days), total absorption by 42 days
*Expensive
78
What are the properties of the Vicryl coated suture?
Vicryl Coated – wound support for 28 days, total absorption at 56-70 days [cheaper]
79
What is the Vicryl plus suture?
- Suture with antibacterial properties
- Not demonstrated for intra-oral use yet
80
What size sutures are used?
3-0 for mandibular third molars
4-0 for most cases
5-0 is the smallest
