Oral Surgery Flashcards
1-55 L1: Midface Fracture Orthognathic surgery: 56-81 Radiotherapy and Chemotherapy neck and head: 82-109 Oral Cancer: 110-120 Management of Fracture of the mandible: 121-156 Referral to Oral Medicine and biopsy: 157-186 Salivary gland disease: 187-241
What type of energy is needed to cause midface fractures?
High energy high impact forces.
- RTA
- Severe assault weapons
- Falls from height
- Industrial
- Agriculture
- War injuries
The middle facial skeleton is defined by?
Superiorly;
* Frontozygomatic
* Frontonasal
* Frontomaxillary
Inferiorly;
* Occlusal plane upper teeth
* Alveolar ridge (edentulous)
Posteriorly;
* Pterygoid plates sphenoid
what is the name of this bone?
Zygomatic
What is the name of this bone?
maxilla
What is the name of this bone?
Zygomatic process of temporal bone
What is the name of this bone?
Palatine bone
What is the name of this bone?
Nasal bone
What is the name of this bone?
Lacrimal bone
What is the name of this bone?
Vomer
What is the name of this bone?
Ethmoid
What is the name of this bone?
Two inferior conchae
what is the name of this bone?
Pterygoid plates of sphenoid
Air containing sinuses interrelated pillars or struts stability via paired buttressing system aligned in three ways, what are they?
- Vertical
- Horizontal
- Sagittal
What are the horizontal buttressing system of the midface?
- Superior orbital rim
- Inferior orbital rim
- Maxillary alveolus
- Palate
- Serrated edges greater wings of sphenoid
- Zygomatic arches
The vertical buttressing system is primarily for which forces to transmission to skull base?
Masticatory.
The vertical buttressing system includes which three systems?
- Nasomaxillary
- Zygomaticomaxillary
- Pterygomaxillary
Where is the lateral pyriform rim located and which part of the vertical buttressing system are they?
Nasomaxillary
Where is the frontal process of the maxilla located and which part of the vertical buttressing system are they?
Nasomaxillary
The lateral pyriform, maxillary process and the frontal process superiorly of the maxilla make up what part of the vertical buttressing system?
Nasomaxillary
The maxillary process of the frontal bone belongs to which vertical buttressing system?
Nasomaxillary
The zygomaticomaxillary buttressing system runs which bones?
- Frontal bone superiorly
- Lateral orbital rim
- Zygoma
- Zygomatica process of the maxilla
What does the pterygomaxillary buttress include?
- Pterygoid plates of the sphenoid
- Maxillary tuberosity
What are the buttressing sagittal?
- Zygomatic arches
- Palate
- Floor of orbit
The middle third facial skeleton has three low tolerance impact zones, what are they?
- Nasal bones least resistant
- Zygomatic arch directly
- Maxillae – horizontal forces
This image represents the degree of posterior displacement, why is that the displacement is decreased as it moves posteriorly?
The displacement is decreased due to the posterior dentition between the maxilla and mandible.
What are the potential results of midface trauma?
- Anterior open bite
- Facial lengthening
- Extreme – soft palate obstruct airway
- Nares blood clot conscious – ok
- Coincident head injury = danger until airway clear
Forces directed where will result in a Le Fort 1 fracture line?
Forces above the dentoalveolar segment
Which part of the pterygoid plates are affected within a Le Fort 1 fracture?
Lower parts of the pterygoid plates
List the areas affected with a Le Fort 1 fracture?
- Lateral nose/piriform aperture
- Anterior/lateral/inferior wall max sinus
- Maxillary tuberosity
- Horizontal maxillary fracture
- Separating the teeth
- Whole complex of alveolar
- Palatal process of maxilla
- Horizontal plates palatine bones
- Lower parts of the pterygoid plates (pterygomaxillary junction)
- Can affect the following – nasal septum, septal cartilage and AKA Guerin fracture
Forces directed where will result in a Le Fort II fracture?
Forces (superior) directed at nasal bones
Le fort II fractures can be described as what type of structure?
Pyramidal (structure) fracture
List the areas affected with a Le Fort II fracture?
- Teeth at the pyramid base
- Nasofrontal suture remnant apex
- Posterior alveolar ridge
- Lateral walls of the maxillary sinuses
- Inferior orbital rim
- Nasal bones
- Nasofrontal junction of the frontal process of the maxilla
- Separates the whole maxilla with part of the nasal bones and the lower part of the pterygoid plates.
Forces directed where will result in a Le Fort III fracture?
Level of orbits
List the areas affected with a Le Fort III fracture?
- Craniofacial distraction with a transverse line
- Transverse fracture line
- Nasofrontal suture
- Maxillofacial suture
- Orbital wall
- Zygomatic arch and zygomaticofrontal suture
- Zygomaticomaxillary complexes
- Nasal bones
- Palatal bones
- Most of the pterygoid plates
If fracture is pan facial what does that mean?
It means that it is a combination of the Le Fort fractures.
With all midface fractures, there needs to be an initial management first, what are these initial managements?
- Airway management
- Haemorrhage
- Head injury/Glasgow coma scale
- Secondary survey
As part of the initial management, airway management is crucial, how can the following affect airway?
- Physical anatomy changes: maxilla and lower face height may push down the soft palate on the dorsum of the tongue causing a physical airway obstruction
- Swelling: of the nasal passages by local oedema
- Bleeding: into the nasal passages
- Loss of consciousness
- Head injury and respiratory depression
With midface fractures haemorrhage is most likely to occur where?
- Haemorrhage involving the maxillary artery
- Nasal walls
- Septal haematoma
- Retrobulbar haemorrhage
What type of haemorrhage is this?
Retrobulbar haemorrhage
What type of haematoma is this?
Septal haematoma
What is a haematoma?
A haematoma is a collection or pooling of blood outside the blood vessel.
How should head injuries be assessed?
Glasgow coma scale
The Glasgow coma scale uses three parameters, what are they?
- Eye opening
- Verbal response
- Motor response
The Glasgow coma scale has a range for its scoring, what is it?
3 – 15
The secondary survey for head and neck assessment is an extra oral assessment and includes assessment of what?
- Asymmetry
- Lacerations
- Ecchymosis (bruising)
- Discharge nose/ears
For the detection of direct midface fractures you should examine patients systematically and manually palpate bilaterally which would include which structures?
- Frontal bones
- Supraorbital rims
- Frontonasal suture
- Lateral orbital rims
- Zygoma
- Zygomatic arch
What are the presentation and clinical findings of le Fort 1 fractures
- Mobility of tooth-bearing segment of the upper jaw
- Crepitus in buccal sulcus
- “Cracked-pot” percussion note from upper teeth
- Intra-oral haematoma in buccal sulcus
- Palatal haematoma?
- Fractured teeth cusps
- Bruising of upper lip and lower mid-face
What is does crepitus mean?
In orthopaedic medicine and sports medicine, crepitus describes a popping, clicking or crackling sound in a joint.
What are the presentation and clinical findings of le Fort 2/3 fractures
- Bilateral peri-orbital bruising (“panda eyes”)
- Subconjunctival haemorrhage
- Lengthening of face
- Malocclusion - AOB
- Gross oedema of face
- Nasal deformity
- CSF rhinorrhoea
- Diplopia and other visual problems
- Mobility of the upper jaw
- Palatal haematoma
What type of scan needs to be used to identify Le Fort fractures?
CT scan
What fracture lines need to be present to determine a midface fracture?
Pterygoid plates mandatory unique fracture lines.
This coronal view demonstrating a fracture where?
Lateral piriform aperture
After patient is stable aim: restoration of normal function which includes?
- Ocular
- Nasal
- Oral
- Dental
- Aesthetics (symmetry)
What does open reduction mean in surgery?
During an open reduction, orthopaedic surgeons reposition the pieces of your fractured bone surgically so that your bones are back in their proper alignment. In a closed reduction, a doctor physically moves the bones back into place without surgically exposing the bone.
What does internal fixation mean?
Internal fixation is an operation in orthopaedics that involves the surgical implementation of implants for the purpose of repairing a bone.
What is Rowe disimpaction forceps used for?
Rowe Disimpaction Forceps are specialised instruments that maxillofacial surgeons can use to separate the maxillary bones in cases of impacted fractures of the facial skeleton.
What does Orthognathic mean?
Straight jaws. Surgical manipulation to produce optimal dentofacial function and aesthetics.
What are the 5 skeletal relationships?
- Class 1
- Mild
- Moderate
- Severe
- Extreme
What are the indications for orthognathic surgery?
Skeletal discrepancy
- Anteroposterior: skeletal class 2/3
Vertical discrepancy
- Open bite
- Deep bite
- VME
Lateral discrepancy
- Crossbites
- Asymmetries
Other clinical/psychological factors
Function
- Eating/chewing
- Speech
- TMD
- Sleep apnoea
Aesthetics: teasing and bullying
- Social
discrimination
- Psychological distress
Pain/discomfort
What factors need to be taken in consideration for Orthognathic surgery?
- Psychological status
- Family support
- Dental health
- Cooperation
- Age?
Why should treatment timing in relation to skeletal growth be taken into consideration of Orthognathic surgery?
Growth stops around age 18 (female) to 20 (male). And sometimes some cases might resolve itself.
When undergoing Orthognathic surgery, you would need a multi-disciplinary team, what does this team include?
- Orthodontics
- Oral and maxillofacial surgery
- Clinical psychology
- Restorative dentistry
- Maxillofacial technology
- Dental hygienist
- Dietician
- Speech and language therapy
What is the treatment process Orthognathic surgery?
- Referral
- Assessment and diagnosis
- Joint clinic
- Pre-surgical orthodontics
- Orthognathic surgery
- Post-surgical orthodontics
- Retainers/review
Who usually does the referral for Orthognathic surgery?
Usually to orthodontics by GDP/GMP
What falls under special tests?
- Radiographs
- DPT
- Intra-Orals
- Cephalometry - Study Models
- Clinical photography
- Other imaging
- Psychological data + BMI (@joint clinic)
What are we looking for in radiographs in the DPT/Intra-Orals?
- Caries
- Periodontal disease
- Root resorption
- Condylar hyperplasia / degenerative changes
- Other pathology
hat is the purpose of the joint clinic? Treatment plan
Treatment plan
Why is there a psychological assessment needed to be done for Orthognathic surgery?
- Questionnaire based
- Referral to clinical psychologist where required for further assessment
- 20% of orthognathic patients have psychologic distress or psychiatric disorders - Psychological therapies where body dysmorphic disorder identified
Body mass index guide are?
- Underweight = <18.5
- Normal weight = 18.5 – 24.9
- Overweight = 25-29.9
- Obesity > 30
What is the purpose of pre-surgical orthodontic treatment?
- Required so teeth occlude properly at time of surgery
- Upper and lower fixed appliances
- Align
- Decompensate
- Coordinate
Alignment involves the correction of what before Orthognathic surgery?
- Crowding
- Spacing
- Rotations
What is the purpose of decompensation?
in preparation for orthognathic surgery, it is necessary to remove any dental compensations present and to place the teeth in a favourable position with their supporting bone. This is called presurgical decompensation.
Crowding and decompensation dictate extractions, for class II cases what are removed?
Lower premolars
Crowding and decompensation dictate extractions, for class III cases what are removed?
Upper premolars
For coordination it is important for what?
- Good planned occlusion with no crossbites
- Arch expansion
What is the purpose of model surgery?
- To determine post-surgery occlusion
- To measure surgical movements
- For wafer manufacture
What is an acrylic wafer?
The acrylic occlusal wafer is a thin piece of plastic which fits between and indexes the occlusal surfaces of the maxillary and mandibular teeth. The wafer enables the dental arches to be put in any desired pre-planned position
How long does it take roughly for a single jaw to undergo orthognathic surgery?
2-3 hours, bimax 4-5 hours.
What is bilateral sagittal split osteotomy?
A bilateral sagittal split osteotomy is a type of jaw surgery in which the lower jaw (mandible) is split bilaterally (moved forward or backward) to straighten it to a more balanced and functional position. It is performed to correct types of malocclusion, a misalignment of teeth.
What is a body ostectomy?
A mandibular body ostectomy is an osteotomy with a segmental resection of a defined section of the mandibular body. The inferior alveolar nerve typically crosses the osteotomy sites and the bony piece which has to be resected.
What is a genioplasty?
Chin augmentation using surgical implants can alter the underlying structure of the face, providing better balance to the facial features. The specific medical terms mentoplasty and genioplasty are used to refer to the reduction and addition of material to a patient’s chin.
What are the treatment options for head and neck cancer?
- Surgery
- Radiotherapy +/- SACT
- Systemic Anti-Cancer Therapy (SACT)
- Supportive care
How does radiotherapy work?
- High energy x-rays
- Targeted to tumour +/- nodes
- Avoiding organs at risk
What three types of radiotherapy are there?
- Radical (curative)
- Adjuvant (after surgery)
- Palliative
What is the aim of immobilisation in radiotherapy?
The aim of immobilisation in radiotherapy is to secure the patient is in the same position at each treatment fraction. This is required in order to deliver the planned radiation doses accurately.
What is the aim of planning in radiotherapy?
Before you begin radiation treatment, your radiation therapy team carefully plans your treatment in a process called radiation simulation. Treatment planning usually involves positioning your body, making marks on your skin and taking imaging scans.
What is contouring in radiotherapy?
Contour delineation is a critical process in treatment planning because it involves outlining tumour (or areas at risk of microscopic disease) as well as nearby organs at risk (OARs) to guide radiation therapy plans that optimize tumour control and reduce radiation toxicity.
What are the advantages/disadvantages to radiotherapy?
Advantages – preserves tissue function, treats microscopic disease
Disadvantages – 4-6 weeks treatment, acute side effects, late sequelae
What are the acute side effects of radiotherapy?
- Skin reaction
- Mucosal reaction
- Fatigue
- Glut -
What are the late side effects of radiotherapy?
- Dry mouth – caries
- Altered taste
- Fibrosis
- Telangiectasia - small, widened blood vessels on the skin.
- 2nd malignancy
Systemic anti-cancer therapy (SACT) includes?
- Conventional chemotherapy
- Drugs which target the immune system (monoclonal antibodies)
SACT: conventional chemotherapy features include?
- Inhibit cell division
- Single agents or combination regimes
- Delivered in cycles
- Dose calculated on body surface area or renal function
What are the monoclonal antibodies used for SACT?
- Cetuximab – targets epidermal growth factor receptor (EGFR)
- Nivolumab & Pembrolizumab – checkpoint inhibitors (PD-1), which upregulates the immune system to target cancer cells
What are the potential advantages of SACT?
- Improved survival
- Improved local control
- Decreasing incidence distant metastases - Relief of symptoms
- Decreasing tumour size
What are the potential disadvantages of SACT?
- Increased toxicity
- May increase rate of treatment related deaths
When do we use SACT?
- Squamous cancers
- Locally advanced disease
- 50-60% advanced patients have local disease recurrence within 2 years
- 20-30% develop metastatic disease - Palliation of symptoms (locally advanced and metastatic)
What are the features of leukoplakia?
- Diagnosis of exclusion; white plaque attributable to no other cause
- Prevalence 1-4%
- Homogenous or non-homogenous, focal or multifocal
- Incisional biopsy/mapping biopsies/excisional biopsy
- Malignant transformation 8-22%
- Dysplasia/CIS/SCC in 40 – 46%
- Surgical excision/serial biopsies/serial reviews with photography
What are the features of erythroleukoplakia?
- Non-homogenous leukoplakia
- red, pebbly granular plaque
- Least common oral PMD
- 90% will have dysplasia/CIS/invasive disease on biopsy (high risk)
What are the featured of submucous fibrosis?
- Characterised by juxtaepithelial inflammation and fibrosis of oral mucosa with progressive trismus
- Areca nut (betel quid contains areca nut) (+ genetics?)
- Induces activity of TGF-beta and produces collagen, inhibits collagen degradation, causes fibrosis
- India, Pakistan, Bangladesh (and families in UK)
- Mucosal burning/ulceration/dryness fibrosis/rigidity/trismus
- Transformation rate 7%-30%
- Medical/physical/surgical management
What are the features of Proliferative Verrucous Leukoplakia (PVL)?
- Progressive, multifocal, exophytic, persistent
- No risk factors
- Oral microbiome dysbiosis may be contributory
- Elderly women
- Separate entity to leukoplakia
- Malignant transformation 70% - 100% (but no risk factors) (average transformation duration 23 months)
- Histological grading scale (1-10) (Hansen)
- Management controversial (similar transformation rate in surgical and conservatively managed groups)
- Surgery still mainstay of treatment
What type of fixation method is this?
Open technique – mini plates
What type of fixation method is this?
Open technique – reconstruction plates
this is an example of what type of fracture?
symphyseal fracture
- A 21 year-old student attends with pain from his lower jaw after being hit the face with a squash racquet the day before. He can bring his teeth together although it is painful.
What is highlighted by the arrow and what does it indicate?
Haematoma at the floor of the mouth
- What radiographic views would you take and why?
DPT and PA mandible giving us a 3-dimensional view of the fracture
You are out with your friends for a bike ride and one of them comes off at speed and lands badly. They are in a lot of pain from their mouth and are bleeding a lot.
what type of fracture is this?
mandibular fracture – step formation present.
When you see a badly displaced fracture, what should you be thinking regarding the other surrounding structure?
Likelihood there are other fractures present.
How do you manage this?
Use occlusion to reduce the fracture. Place two plates, based on Champneys principle.
Case 4
* A 18 year old man fall whilst running for a bus yesterday. He damaged his face and jaw so went to A&E who cleaned his wounds and put some paper stitches on his cut. They told him the injuries were superficial but he has a numb lower lip and teeth on the right side. The wound on his chin is seeping blood. As you are his dentist he wants you to check that his teeth are okay as they are numb.
- Why do you think he has a numb lip?
- If the impact of the fall was the right side lower boarder of the mandible what pattern of fracture could he have suffered?
- When performing a clinical examination what would you be looking for?
- How would you investigate his injuries?
- Who might you refer the patient to and in what time frame?
- Would you organise a review with this case and why?
- The patient asks will the numbness improve – what so you tell him?
q1. Fracture of the mandible, because of presentation of numb lip and teeth
q2. Left condylar fracture
q3. Condylar fractures – pain on opening, pain on palpation, limitation of opening, pain near ear, deviation of mouth opening, deviation of chin.
Q4. DPT and PA mandible
Q5. Send them to A and E same day
Q6. Yes, I would absolutely organise a review, for the assessment of his teeth.
Q7. Yes, would improve unless severance of nerve.
Case 5
You have been asked to do a domiciliary visit to an elderly lady who fell out of bed. She is edentulous but was not wearing her dentures at the time. She is in a lot of pain.
- What do you see on clinical examination that gives an indication of her injury?
- What other questions could you ask about her symptoms?
- What would you recommend?
Q1. Dark bruise, haematoma = fracture of the mandible, gravity has pulled the blood down the fascia planes which is normal, might find bone mobility when palpate.
Q2. Ask if there is any numbness of the lip, ask her if she can swallow or talk, ask for loss of consciousness.
Q3. Sent in to A&E for x-rays.
Case 5
* She has been seen by the maxillofacial team and they have taken CT scan.
- What do you see on the scan?
- What treatment is likely to be offered?
- What implications does that have for you as her dentist?
- If she was on IV bisphosphonates for myeloma what is she at risk of and how much of a risk?
Q1. Bilateral symphyseal fracture. Hasn’t displaced to the characteristic bucket handle fracture.
Q2. Open reduction internal fixation, with large reconstruction plates.
Q3. How uncomfortable it will be for her to wear her dentures after this, the reconstruction plates will be sitting on the labial sulcus, which means lumpy bits sticking out, which will interfere with the sitting of the dentures. May need to make new dentures.
Q4. 1/10 chance of developing MRONJ.
Case 6
A 51 year lorry driver was in a RTA and his chin hit the driving wheel causing facial injuries. As a CT in the maxillofacial department you are asked to see him in A&E.
* What do you think about his occlusion?
* What do you see in the DPT?
* What treatment will he need?
* How can the occlusion be used to help reduce the fracture?
* What sites need to be treated?
Q1. Does not have occlusion with his upper teeth, lower teeth occlusion with last standing molars. Find out what their normal occlusion is, look out for wear facets, and look for pictures to identify previous occlusions. Anterior open bite present
Q2. Left Para symphyseal fracture going from tooth 35 obliquely to the midline, this alone would not cause an anterior open bite. Displaced extracapsular fracture of the right condylar neck. This has caused shortening of the length of the ramus. Bilateral condylar fracture, not as bad on the left side.
Q3. Open reduction internal fixation for Para symphyseal fracture, open reduction internal fixation on the worst condylar fracture.
what does this clinical picture show?
A mucocele
a mucocele is usually caused by trauma to the lower lip by the lower teeth, damaging a salivary duct that would otherwise drain to the floor of the mouth but instead drains?
At the labial mucosa.
What is the treatment option for a mucocele?
Incise the mucocele and the damaged salivary duct, otherwise recurrence will occur.
What is the name of this condition?
Epulis, in this case it is a pyogenic granuloma.
What causes this?
Often a chronic irritation
How much of the pyogenic granuloma needs to be excised?
The blue lines indicate the periphery of the incision.
What is the name of the condition?
Denture induced hyperplasia
What is the name of this condition?
Leaf fibroma as a result of pro longed wearing of a denture.
What type of biopsy would be appropriate here?
Field/mapping biopsies
The submandibular gland is encapsulated and covered by?
Cervical fascia and stylohyoid ligament, which drains via Wharton’s duct in the floor of mouth
Sublingual gland is the smallest of the gland which lies in floor of mouth, covered only by oral mucosa. So very easy to palpate.
The sublingual gland drains to the oral cavity via small and common ducts what are the names of the ducts?
Small ducts – Rivinis’s duct
Common duct - which joins the submandibular duct called Bartholin’s duct
The sublingual gland sits on top which muscle?
Mylo-hyoid muscle
This clinical picture shows a patient suffering from acute sialadenitis, with pus present in the parotid gland, how would you manage this patient?
- Do not incise and drain as primary care – facial never present and vessels
- Referring on for intravenous antimicrobial
- Refer to maxillofacial to determine to affect drainage
when looking for stones in the ducts via radiograph we can classify them as what?
- Intraductal – you can retrieve them under local anaesthetic.
- Intraglandular – surgical removal of the gland (one removal of gland will not result xerostomia)
When surgically removing a stone from a duct, what can you do to prevent the stone from moving back up the duct or forward?
You can place sutures on the posterior and anterior aspect of the duct where the stones lie, this would prevent it from traveling away when trying to remove it.
When you have removed the stone, what do you need to use to flush out the duct?
Sterile Saline solution to flush out any stones that may be distal to it.
Why is it important that we do not completely stitch up the incision that we made on the duct after we have removed the stone?
If we stitch up the incision then what can happen is that the incision will heal with scar tissue present making the ductal orifice even smaller then it was originally, which can go on to cause further problems with salivary flow.
The two options are you do not suture and leave it as it is and it will heal naturally, or other option is you partially suture, so that when it does heal, it goes back to original size. As show in the image.
What is lithotripsy?
Is the use of ultrasonic sound to break down calcified stones, traditionally used for the breakdown of renal stones, this method can be used for the same purpose for no invasive surgery.
What method of retrieval is this?
Basket retrieval – works best with relatively small stones.
What is a ranula?
A mucus retention cyst
There are two types of mucoceles what are they?
- Mucous retention cyst – present in the sublingual gland
- Mucous extravagation cyst – presents on the lip after trauma
What is a pleomorphic adenoma?
Pleomorphic adenomas are benign salivary gland tumours, which predominantly affect the superficial lobe of the parotid gland.
Investigation of this would be a incisional biopsy because it is of minor salivary gland, you wouldn’t biopsy a major gland due to underlying tissue, vessels and nerves.
