Oral Surgery Flashcards
(98 cards)
1
Q
Discuss Open subgingival debridement?
A
Any form of periodontal surgery should only be considered once the owners have proven
commitment and effectiveness of oral care. Without this commitment extraction of these to
these teeth should be considered.
It is impossible to effectively perform closed subgingival debridement of periodontal
pockets deeper than about 4 mm. To accommodate effective subgingival debridement a
periodontal flap is created to expose the lesions and improve visualisation.
Gentle handling and protection of these flaps are crucially important to avoid damage.
Flaps created in this way could either be re-sutured in their normal position or repositioned
apically.
Digital pressure after replacement of the flap will reduce the amount of blood clot
accumulated and assist with adhesion of the flap to the underlying tissue.
Releasing incisions should always be made at the line angle of adjacent teeth and never
over the tooth root surface.
2
Q
What is the envelope flap?
A
The incisions for this flap are created along the gingival sulcus and joins the same incision
on adjacent teeth. No releasing incisions are used, and it often creates enough exposure
for effective open debridement.
3
Q
Discuss the triangular flap?
A
Triangle Flap
For this technique the same incision used for an envelope flap (within the gingival sulcus)
is augmented by a single releasing incision, created perpendicular to the gingival
margin/the sulcular incision. This creates a triangular area of improved exposure. If the
direction of blood supply to the gingiva is considered it is usually advisable to create
releasing incisions at the mesial aspect of the sulcular incision.
4
Q
Discuss a pedicle flap?
A
Pedicle Flap
To create this flap, two perpendicular releasing incidents are made at the mesial and distal
aspects of the sulcular incision. This creates a rectangular exposure of a larger area but
also requires more suturing to close the defect, qand also increases post-operative healing
time.
5
Q
What should be considered when making surgical flaps?
A
For all flap techniques, a sharp periosteal elevator is used to elevate the periosteum as
gently as possible away from the underlying bone. Before closure flushing with Hartmann’s
solution is indicated. Simple interrupted sutures using 5/0 or 4/0 absorbable
monofilament material on a swaged-on tapered or revers cutting needle e.g. Monocryl ®
are advised for tension free closure of these flaps.
6
Q
Discuss first intention wound healing?
A
First intention wound healing occurs when primary
closure is achieved by accurate wound margin apposition. We anticipate this
type of wound to heal quickly, with minimal scar formation.
7
Q
Discuss second intention wound healing?
A
Involves formation of granulation and
connective tissue.
8
Q
How do wounds in the oral cavity tend to heal?
A
Wounds in the oral cavity tend to heal faster
and with less scarring than skin wounds.
9
Q
What is Alveolar osteitis?
A
If the blood clot is lost or disintegrates, a localised alveolar osteitis may occur.
Healing is delayed. The infected alveolus remains open or partly covered by
hyperplastic epithelium.
10
Q
What are the two types of bone healing?
A
Direct and indirect. In indirect bone
healing, a callus is formed. Inflammation is followed by proliferation of various
cell types, including fibroblasts, chondroblasts, osetoblasts, osteoclasts.
Granulation tissue is formed between fracture ends which is transformed into
fibrocartilaginous connective tissue and ultimately bone, given optimal
conditions. Direct bone healing will only occur with accurate bone reduction and
rigid fixation, which may be attained by the use of wires or miniplates
11
Q
Discuss infection and it’s effect on healing?
A
Infection: Local factors can encourage a contaminated wound to become
infected; inadequate tissue perfusion, presence of necrotic tissue or foreign
material. To prevent this consider a conscientious surgical technique, and the
use of sterile instruments, in a clean operating environment (i.e. clean teeth
before extractions, and consider use of chlorhexidine solution within the oral
cavity).
12
Q
Discuss Inadequate tissue perfusion and it’s effect on healing?
A
Adequate tissue oxygen levels are vital for
adequate healing. Ischaemic tissues due to poor surgical technique will be
poorly perfused and therefore prone to infection.
13
Q
Discuss age and it’s effect on healing?
A
Age: Oral cavity wound healing is expected to be slower in older rather than
younger animals.
14
Q
What are all the indications for extractions?
A
Periodontitis
o Gross mobility (Mobility grade 3)
o Furcation exposure grade 3, (2 in cats?)
o >50% attachment loss, (>33% in cats?) How do we measure
attachment loss?
o Secondary tooth resorption-type 1 (inflammatory) in cats
Pulp necrosis
o Complicated crown fracture
o Complicated crown/root fracture
o Root fracture
o Uncomplicated crown fracture
o Abrasion
o Discoloured teeth (concussion/ blunt trauma)
o Avulsion/luxation
Tooth resorption- dogs and cats
Caries/decay (dog only)
Feline chronic gingivostomatitis
Canine Chronic Ulcerative Stomatitis (CCUS)
Malocclusions
Persistent deciduous teeth
Fractured deciduous teeth
Supernumerary teeth
Unerupted teeth
Traumatically luxated /avulsed teeth
15
Q
What are the contraindications for extractions?
A
If informed consent has not been obtained
o If the appropriate skills, knowledge and equipment are not available
o If a pre-extraction dental radiograph cannot be obtained
o Age is not a barrier to performing general anaesthesia and dental
extractions
o Extraction of teeth in the field of previous radiation therapy can lead to
osteoradionecrosis and should be avoided (therefore extract necessary
teeth before radiation therapy)
o Extraction of teeth within a potentially malignant tumour at the time of
biopsy
o ‘Disarming’ procedures
16
Q
What is the periodontium?
A
Periodontium (the
periodontal ligament attaches the tooth via the cementum covering the root to the alveolar bone of the socket, and the gingiva also attaches to the tooth surface).
17
Q
The high-speed handpiece (dental ‘drill’) should be lubricated after?
A
Every patient.
18
Q
How does a high speed hand piece work?
A
Compressed air is used to drive the turbine which
rotates at 300-400 000 rpm. A friction-bur is
used (FG) and inserted by depressing the
back of the turbine. The connection to the
dental unit tubing is usually 4 hole
(Midwest), with two larger holes and two
smaller holes. The smaller of the two larger
holes takes the air to the turbine and should be lubricated before sterilising.
Most handpieces state at what temperature to be autoclaved (usually 134°).
Many manufacturers produce handpieces with the ability to swivel 360°, which
are invaluable.
19
Q
How should dental handpieces be held?
A
Dental handpieces should be held in the modified pen grip.
20
Q
What do pre-extractions x-rays allow?
A
Pre-extraction radiographs are strongly recommended (if not mandatory) and
allow detection of anatomical variations, assessment of quality of alveolar bone,
ankylosis or resorption that may make efforts challenging, and other pathology
that could influence extraction technique.
21
Q
What do post-extractions x-rays allow?
A
Post-extraction radiographs are
essential in confirming complete extraction of root, plus absence of any
compromising factors (such as bone or calculus fragments within the alveolus)
22
Q
What is a periodontal probe used for?
A
Periodontal probe
* Blunt ended, graduated mm marking for measuring gingival
sulcus/pocket depth or identifying furcation exposure
o Different styles available, e.g. UNC-15, Williams
23
Q
What is an explorer probe used for?
A
Explorer probe
* Sharp tip, used only on hard dental tissues. E.g. for identifying
resorption, enamel hypoplasia, pulp exposure - but only in the
anaesthetised animal.
o Different styles available, e.g. Shepherd’s Hook, Orban, Cowshorn
24
Q
What should dental burrs be made out of?
A
Tungsten carbide or diamond
25
What are round burrs used for?
Round burs are useful for alveolar bone removal during surgical
extraction techniques, and a range of sizes are required, such as ¼,
2,4,6.
26
What are straight burrs used for?
Straight burs are suitable for sectioning teeth and can be used for bone
removal during open extractions. These may be tapered, and also have cross-cuts (to reduce clogging of the bur with tooth material). These are
therefore described as taper fissure cross-cut burs. Typical sizes include
699, 701.
27
What are diamond burrs useful for?
Diamond burs are useful for smoothing alveolar bone (alveoloplasty)
after extracting teeth surgically. Chose large round or rugby ball shaped
versions with fine or medium grit.
28
What are root tip burrs used for?
Root tip burs are useful for retrieving root fragments
29
How should you use a burr to section teeth?
When using the bur to section a tooth, remember it is not a light sabre.
Apply gentle pressure then release, in a tapping motion through the tooth.
30
What are Luxators?
These are very sharp instruments designed to cut
the periodontal ligament. The blade is thin and
relatively fragile and less concave than an
elevator. They are not designed to withstand
rotational forces. Typically, they have plastic
handles (Luxator is actually a trademark of the
Swedish company Directa). They are used parallel to
the root surface. They are available in widths of 1-5mm,
with straight or angled blades. Forte versions are
available, which are stronger and can be used in a
rotational manner. The palm grip is the correct luxator
grip. The index finger is placed close to the tip of the
blade to prevent trauma should the operator slip
31
What are these?
Luxating Elevators
Other companies produce Luxator-like instruments,
which have fine, sharp cutting blades, designed to cut
(rather than tear) the periodontal ligament. E.g.
Luxating elevators from IM3, and the 1.3mm
and 1.8mm Luxating elevators from Cislak
which are especially useful in feline
dentistry.
32
What is an elevator?
The dental elevator is a thicker, stronger instrument than the Luxator, designed
to transmit rotational force from the blade to the tooth, which tears periodontal ligament fibres, or lifts (elevates) the tooth from the alveolus. Winged versions are available, which contact a greater
proportion of the root circumference thus allowing additional purchase and torque (care! This can cause root fracture).
33
How should elevators be used?
Elevators
should also be maintained in a sharp state.
o Use axially in a twist-and-hold technique. Insert into periodontal
ligament space, apply two-finger rotation pressure to ‘move’ root
within alveolus. Hold this pressure for 10-20s to allow periodontal
ligament fibres to fatigue, then re-position. No wiggling.
o Use perpendicularly to long axis of tooth root in a ‘wheel-and-axle’ technique, using alveolar bone as a fulcrum. This ‘elevates’ the root segment from the alveolus. Gentle and careful continuous
force.
34
Name some good elevators?
Elevation-In-Dent® (Accesia) These
excellent instruments come in 5 widths and
can be used for luxation and true elevation.
35
What is a periotome?
The periotome is a fine bladed instrument which is inserted into the periodontal
ligament space to sever the fibres, while maintaining the integrity of the
alveolus. A mechanical Vet-Tome version is available.
36
How should extraction forceps be used?
Use once the tooth is loosened. Ensure the beaks of
forceps maintain 4-point contact with tooth as close to
apex of root as possible. Do not crush the gingiva.
Rotate until you feel tension, then hold. Rotate in
opposite direction until you feel tension, then hold in
position for 10-15 seconds. Apply traction at the same
time. No fence-post wiggling- a force is created at the
alveolar margin of bone, which will probably cause the
root to fracture. The twisting fatigues and tears the periodontal ligament fibres,
but this does not happen instantly.
37
Name some good root tip forceps?
Root tip forceps and picks are worthwhile purchasing. The very small beaks
allow retrieval of small root tip fragments e.g.
Stieglitz style
38
What are Periosteal elevators used for?
Used during elevation of a mucoperiosteal flap, to elevate periosteum off
underlying alveolar bone. They must have a sharp cutting edge and be
sharpened regularly. The back surface is atraumatic.
Hold them in either the palm or modified pen grip, using in a push-and-twist
action, but with the edge at an angle to the bone to
engage the cutting surface (not parallel to it).
A variety of sizes are required for cats, small dogs
and larger dogs.
o Styles include: Molt, Goldmann Fox,
24G, Freer.
39
What do tissue retractors do?
o Protect tissues and flaps when using
high-speed handpiece.
o Senn, Minnesota
o Tongue depressor, composite spatula
40
What scalpel blades and handles should be used?
o Size #11 or #15/#15c blades are suitable for dental
work, and should always be attached to a scalpel
handle.
o Beaver handle and blade
o Round or hexagonal handles are useful in the
mouth- facilitates cutting the gingival
attachment around the circumference of a tooth.
41
What scissors are needed in dental kit?
o Curved iris/ LaGrange/ Double curved for tissue dissection, periosteal
releasing incisions
o Separate suture scissors
42
What forceps should be in your dental kit?
o Gentle tissue handling forceps should be used, such as the Adson 1x2.
43
What suture materials should be used in the oral cavity?
Suture materials used within the oral cavity should have
the following properties:
➢ Fast absorption with minimal tissue reactivity
➢ Good short-term tensile strength with sutures of small diameter
➢ Minimal plaque retention
➢ Low capillarity
➢ Good knot security
➢ Low tissue drag
➢ Good handling
Monocryl /Caprosyn/CliniMonoQ fulfils many of these characteristics, exhibiting
minimal tissue reaction, good tensile strength, good handling, low reactivity.
Choose fine gauges 4-0/5-0 with a reverse cutting needle. (e.g. Monocryl
W3203, W3209, W3205)
Monocryl Plus has additional triclosan added for antibacterial properties.
44
How should instruments be sharpened?
An excellent guide to dental instrument (scaler and curette) sharpening is
provided on-line by Hu-Friedy and is entitled “It’s about time”. You will require a
sharpening stone (e.g.Arkansas stone), a cylindrical stone, sharpening oil and a
plastic test stick. The plastic test stick is used to test the sharpness of
instruments- they should catch or ‘grab’ the stick and make a metallic pinging
sound when released. A blunt instrument will slide easily over the surface.
45
Discuss the use of prophylactic antibiotics in oral surgery?
Prophylactic antibiotics may be considered for the following patients:
✓ Patients requiring multiple surgical extractions involving ostectomy
✓ Patients with severe generalised periodontitis
© Rachel Perry 2023 www.improveinternational.com | 21
✓ Patients unable to clear the potential bacteraemia (i.e. debilitated,
geriatric, immunocompromised animals, or those with severe systemic
disease.)
✓ Oncological surgery
✓ Maxillofacial trauma
Prophylactic antibiotics should be given at high doses, intravenously 30 minutes
before the start of the procedure. For example, amoxicillin-clavulanate
(Augmentin) or cefuroxime (Zinacef) at 20mg/kg.
46
When should therapeutic antibiotics be used?
These should be used to treat established orodental infections. For instance:
* Established soft tissue infections (cellulitis associated with periapical abscessation)
* Osteomyelitis
* Severe soft tissue trauma
* Rapidly progressive or aggressive periodontitis.
Antibiotics alone should never be used to treat gingivitis or periodontitis.
47
What should antibiotic selection be based on?
Antibiotic selection should be based on likely pathogens involved. Suitable
drugs would include amoxicillin-clavulanate, clindamycin, pradofloxacin,
cefovecin, metronidazole/spiramycin. Both pradofloxacin and cefovecin have
licenses for the treatment of periodontal disease in the dog, but the wording
clearly states this should be used as an adjunct to ‘mechanical or surgical
periodontal therapy in severe infections of the gingival and periodontal tissues’.
48
How can the airway be protected when cuffing?
Cuffed endotracheal tube inflated until escape of gases is just prevented. A pressure device can be useful for this (e.g. a manometer or AG Cuffill), to ensure the inflated pressure does not exceed that of the tracheal endothelial capillaries (25-40cm H2O).
49
When should ophthalmic lubricant be especially used?
Ophthalmic lubrication- use copious amounts, regularly. Post-operative ophthalmic lubrication should be considered after ketamine use, and in
brachycephalic patients.
50
Why should we not use spring loaded mouth gags in cats?
Do not use these in the cat and be cautious of their use in dogs. Research has
shown the maxillary artery is obstructed in feline patients with maximal mouth
opening, and this can lead to post-operative blindness by obstructing the
maxillary artery as it is compressed between the angular process of the
mandible and tympanic bulla with the mouth open. If the mouth does need to be
propped open, use a cut-down needle cap and then only for very short periods
of time.
51
What should be done to to teeth before extractions?
Scale teeth before extracting then rinse mouth with 0.12% chlorhexidine
gluconate solution/spray, such as Hexarinse®. Ensure instruments are clean
and sterile. A surgical autoclavable pack can be created and then stored sterile
until use. When exposing bone during open extractions consider also the use of
sterile gloves and sterile gauze swabs.
52
How would the premolar 1 best be extracted?
Premolar 1 in the dog (105, 205, 305, 405)
These are close to the canine teeth, but tend to have short, conical tapered
roots. Usually straightforward to extract using a closed technique.
53
How should the maxillary premolar 2 in the cat be removed?
Maxillary premolar 2 in the cat (106, 206)
These tend to have short, conical tapered roots, but in one study a single root
was found in 27% cases, a dichotomous in 55% and two roots in 9%.
54
How should the Maxillary molar in the cat (109, 209) be extracted?
This tooth may have one, two or fused roots (35%). Despite this it is typically
extracted without sectioning. It is however located immediately ventral to the
orbit, so that correct technique should be used to prevent slippage and globe
penetration. It is a small tooth, and easily overlooked (especially with cat in
lateral recumbency) unless a careful examination is performed. A wheel-and axle technique can be useful for extracting this tooth.
55
How should canine maxillary molars be sectioned?
The first cut is to section the palatal root
from buccal roots. Next section the two
buccal roots- move bur from buccal to
palatal to the initial sectioning cut.
56
How should closed extractions be done?
The gingival attachment to the tooth is initially incised using a scalpel blade
(e.g. size 15) on a handle. It is placed into the gingival sulcus until it reaches the
alveolar bone, and circumferentially ‘walked’ around the tooth. Angle the handle
at 10-20 to the long axis of the tooth, to insure it reaches the alveolar margin.
Hand instruments are then used to deliver the tooth from the alveolus. Multirooted teeth are sectioned before extraction attempts. It can be helpful to
elevate the gingival margin slightly with a periosteal elevator in order to
visualise the furcation more clearly (and also protect the gingiva when
sectioning). Closure of the site by suturing the gingival margin may or may not
be possible depending on the size of the tooth extracted. Closure is always
preferable as it leads to primary wound healing.
57
How are open extractions done?
Mucogingivoperiosteal flaps are used during open (surgical) extractions and
also during other surgical procedures; such as ONF repair and periodontal
surgery. A local flap is outlined by a surgical incision, contains its own blood
supply at the base and allows access to underlying tissues. It can be replaced
in its original position, or moved (for instance, to cover an alveolus) and is
expected to heal by primary intention (which is predictable and comfortable).
Gingiva, mucosa and the underlying periosteum are elevated off the underlying
bone in a full-thickness flap, using a periosteal elevator.
58
What are the Principles of good flap design?
* Flaps should be of sufficient size to allow adequate surgical exposure
* The base of the flap must not be narrower than the free margin
* The edges of the flap must ideally lie over intact bone, but not a ridge of
bone once sutured into place
* Preserve local blood supply and anatomy by considering adjacent vital
structures such as infraorbital artery, middle mental artery, salivary gland
ducts and use of instruments (e.g. use atraumatic tissue forceps holding
the connective tissue, rather than forceps which will crush the gingival
margin). Remember that every vertical releasing incision can potentially
compromise blood supply to the flap, which is coming up the neck then
coursing rostrally in the mouth.
* Gentle tissue handling.
* Preserve the gingival attachment to teeth remaining in the mouth- do not
make vertical releasing incisions directly on the buccal aspect of a tooth,
as it is hard to re-suture the gingiva around the tooth. It is however
acceptable to release the gingiva from a tooth which is staying in the
mouth. By suturing the gingiva back into place, it can re-attach to the
tooth post-operatively - one suture mesially and one distally.
59
How should an envelope flap be made?
A horizontal incision alone is created, without any vertical releasing incisions.
This is created in the gingival sulcus, and
extended as far caudally as needed- along
the alveolar margin between teeth, then into
the sulcus of the next tooth. A sulcular
incision is made around the entire
circumference of the tooth to be extracted
to release the gingival attachment. A periosteal elevator is then used to raise
both the gingiva and mucosa off the underlying alveolar bone.
60
How is a triangular flap made?
A horizontal sulcular incision is made, plus one
vertical releasing incision which extends beyond
the mucogingival junction. Why? Also consider
blood flow to the flap- where should the vertical
incision de made, caudal or more rostral?
61
What needs to be considered with flap design?
* Flap design- envelope/triangular/pedicle?
* Root anatomy: how long is the root, where is the apex? Ensure your flap
is of adequate size to allow access.
* Do not make a vertical releasing incision too close to the tooth to be
extracted, as you will damage the soft tissues when removing buccal
bone.
* Do not make a vertical releasing incision half way over a tooth that is not
being extracted. Instead, make it at the mesial or distal aspect, so that
suturing will adequately re-oppose the gingiva around the tooth.
62
What is a pedicle flap?
A sulcular incision is made, plus two
vertical releasing incisions which extend
beyond the mucogingival junction.
63
How should buccal bone be removed?
Buccal bone removal
Once the flap is elevated, ideally a bur in a low-speed handpiece with
sterile water cooling is used to remove buccal alveolar bone overlying the
root structure. If this is not available, a bur in a high-speed hand-piece is
used. Bur choice is personal, I prefer a 701L in dogs and 699 in cats,
(taper-fissure cross-cut), but a round bur would also work. Be aware that
the size of the round bur is significant when creating gutters at the
periodontal ligament space (see below). If the bur is too large (e.g. 4 or
above) then the resultant gutter may be too large to allow effective
elevator use. Estimate the length of the tooth root, and then aim to
initially remove bone overlying 33-50% the length of the root. In addition,
we will remove bone overlying the periodontal ligament, creating ‘gutters’
which will allow placement of hand instruments (elevators). Do not go too
deep when removing bone, as it is easy to start burring into the root. You
should see a pinkish colour as you approach the periodontal ligament.
Stop once this is approached. Try to remove bone in a neat way, creating
a dome-shape of bone removal.
64
How should periodontal ligament gutters/grooves be made?
Using a bur of correct size (699, 701L, round ½-1), we then aim to create
gutters in the mesial and distal periodontal ligament space, just over 50%
depth of the root. This must be exactly where the periodontal ligament is,
so do not guess, visualise it! If this is performed after initial buccal bone
removal, you can follow the curvature of the root to lead you to the
position of the periodontal ligament.
65
What should you do to the alveolus before closure?
Debride any granulation tissue/bone or calculus debris from within
the alveolus using a surgical curette e.g. a Lucas curette
. Obtain a post-extraction radiograph to ensure all root substance is
removed, and no foreign
material or bone fragments are
within the alveolus.
66
Discuss alveoplasty?
Using a fine/medium round/rugby ball diamond bur on a
high-speed handpiece with water-cooling/rongeur/bone file to smooth all
bone edges before closing the flap. Run your gloved finger over the bone
to detect any sharp spikes and smooth them off.
67
What are all the steps in a surgical extraction?
1. Flap creation
2. Elevating the flap
3. Buccal bone removal
4. Creation of periodontal ligament gutters/grooves.
5. Section the tooth if necessary
6. Extract each crown-root segment
7. Debride any granulation tissue/bone or calculus debris from within
the alveolus using a surgical curette.
8. Obtain a post-extraction radiograph.
9. Elevate the gingiva
10. Alveoloplasty
11. Test the flap in position
12. Release of tension
13. Suturing.
68
How should the flap be sutured?
Take relatively wide bites of tissue from flap to attached
tissue, entering the tissue with the needle tip at 90. This will mean
pronating your wrist. The needle passes through easily by supinating
your wrist:
a. Needle: small diameter 3/8-1/2 circle with reverse cutting edge
b. Simple interrupted pattern, 2-3mm between sutures or as needed,
suture ends 2-3mm
c. Poliglecaprone 25 (Monocryl ®)
d. Polyglactin 901 (Vicryl ®) is braided and more reactive and
persists longer than is necessary for intraoral healing. Vicryl
Rapide may be a suitable alternative but can be quite brittle due to
the irradiation process.
e. Polydioxanone (PDS®) can be used where extended tensile
strength and delayed healing is anticipated.
Periosteum on underside of flap must be
incised before suturing to release tension on
flap.
Z-shaped scissors being used to blunt
dissect periosteum on the underside of
flap. Do not cut through mucosa!
f. Triclosan-coated materials (“Plus”) are available which are
antibacterial.
Size: Use the smallest size that will appose wound
edges (larger sizes create more friction and provide
more foreign material within the tissues). Sizes 4-0
and 5-0 are most appropriate in dogs and cats.
69
What should post operative care for dentistry be?
Immediate rinsing of the mouth should be performed before extubation. Check
for any debris on the oral cavity, such as calculus, tooth fragments etc. Ensure
there is no fluid and no throat pack at the back of the mouth. Rinsing the mouth
post-operatively at home is generally not necessary. Where delayed healing
may be anticipated, a 0.12% chlorhexidine solution may be considered, but be
aware it is very bitter tasting, and may not be well tolerated. Where there are
open wounds to granulate, Hartmann’s fluid will provide a better wound-healing
environment. A soft (but not sticky) diet should be given for several days. Dog
owners are instructed to ensure their pet does not chew on anything too hard,
including treats, toys, sticks etc. I normally review patients after 2-3 days and
then again at 7-10 days. I try to then review patients in another 3 months also.
70
How is a crown amputation done?
This is an alternative to extraction for cases of type 2, replacement resorption.
This must be diagnosed radiographically. The periodontal ligament surrounding
the root will not be visible, and the root radiodensity will be diminshed, and
match that of surrounding bone. An envelope or triangular gingival flap is
created. For premolars, an envelope flap is appropriate, while a triangular more
suitable for canine teeth. An incision within the gingival sulcus is extended 1-
2mm beyond the tooth of interest both buccally and lingually. The gingiva is
then elevated from the underlying bone using a periosteal elevator, and
protected while the crown is amputated level with, or just below the alveolar
margin using a tapered fissure bur (e.g. 699 or 701) in a high-speed handpiece.
The area is then smoothed with a fine diamond bur. A post-operative radiograph
confirms no sharp edges of bone/tooth, and then the site closed with 1-2 simple
interrupted sutures. Do not leave exposed bone/tooth substance!
71
What happens if you cannot removed a root tip?
If you feel like you cannot retrieve the root tip and could cause more
trauma in trying to do so, then leave the root tip, radiograph it, document it in
the clinical notes, tell the client, and re-radiograph in 6 months time.
72
How should an oronasal fistula be repaired?
Oronasal fistula. A pre-existing ONF may be present at the maxillary canine
tooth or premolars 1-4 due to advanced periodontitis. Extraction of these teeth
should be followed by closure of a mucogingival flap after debriding all oral
epithelium from its ingrowth into the nasal cavity, ensuring you are suturing
freshly cut connective tissue surfaces together. It is vital that the buccal
mucosal flap is large, and is closed with no tension.
73
How can you avoid instrument slippage?
Slippage of instruments: hold instruments correctly with palm grip and index
finger extended towards tip of instrument when applying apical pressure. Use
controlled force. Hold the jaw near to the tooth with the non-dominant hand
when extracting.
74
How can mandibular fracture be avoided?
Mandibular fracture may be caused by inappropriate force or technique when
extracting mandibular canines or 1st molars. Ensure a pre-operative radiograph
is obtained. If there is evidence of type 2 resorption in the feline patient, perform
a crown amputation. Do not apply instruments mesially or distally to the
Repair of the ONF includes removing all epithelium
growing into the nasal
cavity on the palatal aspect mandibular canine tooth when extracting, but rather mesiolingually and
distolingually, using the bulk of the symphyseal bone as leverage. Use a
luxating rather than elevating technique.
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How can you avoid Osteomyelitis/osteonecrosis/alveolar osteitis (‘dry socket’?
Avoid by using
correct techniques, closing flaps tension-free. Avoid undue trauma to boneensure water cooling of burs for example. Use sterile instruments with good
surgical technique.
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How can you avoid Subcutaneous emphysema and air embolism?
Do not direct the high-speed
handpiece or three-way syringe jet of water/air into an alveolus. Use the air jet
cautiously, and not directly into a socket.
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How can pain be managed?
Pain. Remember animals have often been in chronic pain for many months or
years before treatment is obtained- this can lead to a wind-up phenomenon.
Surgical pain is then additionally created. Try to avoid undue surgical pain by
using correct, sharp instruments with a good surgical technique. Encourage
nurses to perform pain scoring on patients in recovery. Do not withhold
additional analgesia if it is required. Consider repeat opioid injections. Provide
post-operative NSAIDs where safe to do so, plus possible additional analgesics
if required. E.g. transmucosal buprenorphine in the cat, tramadol, transdermal
fentanyl, gabapentin
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What can cause delayed healing?
Delayed healing may be anticipated in Cushingoid patients, Diabetic patients
and those on immunosuppressive drugs. Local factors contributing to delayed
healing include; sharp alveolar bone edges, protruding root remnants.
Neoplasia may be an underlying cause of non-healing extraction sites. Consider
biopsy, and obtain dental radiographs if not already.
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What causes wound dehiscence?
Dehiscence is typically caused by tension on the wound, usually caused by
inadequate fenestration of the periosteum, or siting vertical releasing incisions
(and therefore suture lines) over voids or ridges of alveolar bone.
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What is Glossoptosis?
This can occur after extraction of lone or both mandibular canine
teeth, as these usually serve to contain the tongue within the mouth. Warn the
client this may occur
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Why is root atomisation- contraindicated?
Root atomisation: the ‘drilling of roots’
This practice is unacceptable and highly dangerous. There are serious risks of
bone necrosis and delayed healing, injury to neurovascular bundles (the
haemorrhage can be catastrophic), repulsion of root fragments into the nasal cavity or mandibular canal and potentially fatal air embolisms. Furthermore, it is
highly unlikely that you will actually remove the entire root fragment. Do not do it.
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What gives rise to the primitive oral cavity?
During normal palate development, mesenchymal cells from the neural crest
migrate to the primitive oral cavity whereupon they differentiate into cells which
will form both the primary and secondary palates. Nasal processes fuse with
maxillary processes to form the upper lip and primary palate (which terminates
at the palatine fissures). The secondary palate forms by fusion of the palatal
processes from the maxilla- these also fuse with the primary palate at the
maxilloincisive suture. The formed hard palate now fuses with the vomer to
complete separation of oral and nasal cavities.
83
Discuss palatal clefts?
Palatal clefts are either congenital or acquired. Congenital cleft palate
(palatoschisis) involves the secondary palate and can be spontaneous or due to
some external influence, such as teratogens. It can involve all of the hard palate
caudal to the palatine fissures, and the soft palate.
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Discuss the cleft lip (cheiloschisis)?
Cleft lip (cheiloschisis) is a defect involving the primary palate. A complete
cleft lip will include all the lip and continue into the nostril either uni- or
bilaterally. This is usually associated with a cleft in the alveolar process (the
bone surrounding teeth) and are confined to the incisive bone only. Surgery to
repair the cleft lip is technically challenging and prone top dehiscence. These
procedures should only be attempted by surgeons with previous (successful!)
experience in their repair. Teeth will often be malpositioned if there is an incisive
bone defect. Extract any which may contribute to pain or dysfunction.
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What is the surgical anatomy of the palate?
Surgical anatomy
The incisive, maxillary, and palatine bones form the roof of the mouth. The major palatine arteries are the main arteries to the mucoperiosteum of the hard palate and emerge at the major palatine foramen coursing rostrally in the
palatine groove. These foraminae are located medial to the maxillary 4th premolar, roughly halfway between the dental arcade, and mid-line.
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What are the considerations for congenital cleft palate repair before attempting to repair?
With congenital clefts, a quick decision must be made as to the likelihood of
successful repair. Clients should be counselled as to the requirement for
surgery, likely costs and number of procedures before embarking on hand rearing these animals. Repair should be delayed until the animal is at least 4
months old.
Cleft lip repair is technically challenging and is best referred to Specialists with
successful experience.
The best chance of success is on the first surgical attempt.
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Congenital cleft palate repair has two basic techniques. What are they?
1) Von Langenbeck technique
2) Overlapping flap technique
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How is the Von Langenbeck technique done?
In this technique, bilateral releasing incisions are made 2mm from the maxillary
teeth, parallel to the dental arch. The margins of the cleft are excised. The
mucoperiosteum is undermined, taking extreme care not to damage the palatine
arteries. The flaps are re-positioned medially and sutured over the defect. The
resulting gaps at the lateral edges are left to heal by second intention.
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What is the Overlapping flap technique?
This technique is often preferred as there is less tension on the suture line,
the suture line is not directly over the defect and the area of opposing
connective tissue is greater (hence stronger repair).The first incision is made
on one side, 2-3 mm from the maxillary teeth and extended perpendicularly
at the rostral and caudal aspects to extend to the cleft. The caudal incision
should lie over hard palate bone (not in soft palate). This flap is then
elevated to the edge of the cleft, ensuring the palatine artery is preserved. At
the level of palatine fissure, the flap is only partial thickness, ensuring some
tissue remains over the fissure. This flap will be then hinged completely over the cleft. It is therefore vital not to penetrate the epithelium here- where the
oral and nasal epithelium are confluent. The second incision is made along
the entire length of the defect on the opposite side at the cleft margin, and
then the oral mucoperiosteum is elevated only 8-10mm from the edge. The
first flap is then rotated 180 and tucked under the mucoperiosteum of
second flap, so it rests between hard palate and flap- allowing two
connective tissue surfaces to contact one another. Multiple horizontal or
vertical mattress sutures are placed from caudal to rostral- these can be preplaced and held with haemostats. The defect created by the hinging of the
first flap is left to heal by second intention and is usually re-epithelialised
within 4 weeks.
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How can the soft palate be repaired?
Defects on the soft palate can be repaired using a double layer appositional
technique. An incision is made along the medial aspects of the defect to the
level of mid-caudal tonsil. Metzenbaum scissors are used to separate the
palatal tissue. The nasal epithelium is sutured first in a simple interrupted
Pre-operative appearance
of a 6m FN Pug with
complete cleft of secondary
palate, involving hard and
soft palates.
Planned surgical
incision. The flap to
be hinged is outlined
on the patient’s left
side.
The edge of the cleft on the patient’s
right side is excised, and
mucoperiosteum elevated for 8-
10mm. The first flap is then hinged
over and tucked underneath this
flap. Horizontal mattress sutures
were placed. The soft palate was
repaired as described below.
Post-operative appearance at 4
weeks. The area left to granulate has
completely re-epithelialized.
© Rachel Perry 2023 www.improveinternational.com | 48
pattern. Very fine monofilament material can be used in a continuous pattern in
the muscle/connective tissue layer, but is not essential. The oral epithelial layer
is then sutured with simple interrupted sutures. The end of the repaired soft
palate should terminate at the mid-caudal tonsil, and just rest on the epiglottis.
Lateral, partial thickness releasing incisions can be made if tension relief is
required.
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How should Acquired cleft palates be repaired?
These can occur during traumas such as road traffic accidents, and falling from
a height. In the acute stages, these will not be lined by epithelium, and may heal
spontaneously if left. However, the risk is that they will epithelialize and form an
ONF, so are often best repaired. Midline, sagittal fractures/separations can
often be repaired by digital pressure to close the cleft, along with simple
interrupted sutures once the patient is safe to anaesthetise. Be aware there are
likely to be multiple injuries requiring attention, including fractured teeth with
pulp exposure. Advanced imaging techniques such as CT or CBCT are
invaluable in diagnosing the extent of maxillofacial injuries in traumatic cases. In
more long-standing cases, a von Langenbeck technique is more appropriate, or
a double layer technique combing staged extractions.
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What is an oronasalfistula?
This describes an abnormal communication between the oral and nasal
cavities, lined by epithelium.
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What can cause acquired oronasal fistulas?
Acquired ONF’s can occur due to bite wounds, blunt head trauma,electrical/chemical burns, gunshot wounds, foreign body
penetration and pressure necrosis, periodontitis, neoplasia, malocclusion, oral
disease (e.g. eosinophilic granuloma), radiation necrosis or dehiscence of surgical wounds. The most common cause seen in practice is periodontitis.
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How can a diagnosis of oronasal fistula due to periodontitis be made?
A diagnosis can be made by thorough probing of maxillary teeth. A deep
probing depth should alert the clinician to the possibility of an ONF. If blood is
seen at the ipsilateral nostril, the diagnosis is confirmed. Although dental
radiographs are not sensitive for detecting an ONF per se, they are important, especially is neoplasia is suspected. So, an ONF may be present when there is
a tooth in situ, you just can’t see it. Without going through the following steps,
the ONF will be obvious at the post-operative check. Although the maxillary
canine tooth is often affected, it can be seen on any pre-molar within the
maxilla, including the carnassial.
Diagnosis can be easily (and cheaply) achieved by performing thorough oral
examinations including meticulous probing.
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What are the various methods for repair of oronasal fistula due to periodontitis?
Various forms of treatment have been described, including; Single layer buccal
mucosal advancement flap, double-layer flaps, auricular cartilage autografts,
greater palatine axial pattern flaps (such as; transposition flap, split palatal Uflap), angularis oris axial pattern flap and the use of poly-vinyl silicone
obturators.
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What is the simplest form of oronasal fistula repair?
The simplest form of repair is using a single layer buccal mucosal
advancement flap.
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What are Transposition flaps (greater palatine axial pattern flap) good for?
These are recommended for small circular defects, especially if lateral to the
midline and rostral to the 4th premolar. They utilise and mobilise the greater
palatine artery and vein. These flaps should be designed significantly larger
than the defect to be covered. The rim of the fistula is initially excised. The flap
is designed as a “U” shape, with one arm adjacent to the defect. Rostrally the
palatine artery must be identified and ligated. The mucoperiosteum is elevated
using a periosteal elevator, taking care not to traumatise the palatine artery. It is
then rotated (transposed) to cover the defect and sutured with simple
interrupted sutures.
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When is a Split Palatal U Flap used?
This is useful for caudal and central palatal defects. The margin of the defect is
excised. Two U-shaped mucoperiosteal flap are created on both left and right
sides. Each will contain the major palatine artery, which should be ligated at its
most rostral aspect as the flap is raised. One side is rotated over the palatal
defect and sutured to the margin. The second flap is also rotated and positioned
rostral to the first flap, and then sutured to the first flap. The rostral area of
exposed bone is left to heal by secondary intention.
