Oral Surgery Flashcards
What type of pressure allows expansion of a cyst causing osteoclastic bone resorption?
Hydrostatic pressure
What type of swelling are cysts when they present in the mouth?
Fluctuant, fluid-filled swelling
What are 10 signs/symptoms that might suggest a cyst is present?
- Asymptomatic, chance finding on radiograph
- Eggshell crackling (crepitus upon palpation) indicating bony expansion
- Fluctuant swelling
- Missing teeth or loose teeth
- Carious, discoloured, fractured, tilted/displaced teeth
- Discharge/sinus
- Mental hypoaesthesia
- Hollow percussion note
- Pain and swelling is secondarily infected
- Pathological fracture
What are the 4 investigations required for cyst diagnosis?
- Sensibility/sensitivity testing
- Radiology
- Aspiration of cyst contents
- Biopsy
What are the two most common treatment options for cysts?
ENUCLEATION or MARSUPIALISATION
What factors influence choice of treatment of a cyst?
- Type of cyst
- size of cyst
- site of cyst
- the patients general medical status
What procedure completely removes the cyst lining and allows for healing by either primary or secondary intention?
ENUCLEATION
Where do you want to plan the incison of a flap during the ENUCLEATION process?
Further away from the osteotomy site, do not let it rest directly over site.
After ENUCLEATION, dead space is left. Why is dead space a disadvantage surgically?
Due to potential for reactionary haemorrhage and problems with post-op infection
What are the 5 advantages of eliminating or reducing dead space?
- Vacuum drain: it sucks down size of overlying mucosa to minimise amount of dead space, this will help in the initial post-operative period by dealing with any reactionary haemorrhage.
- Collapsing wall of cavity (saucerization): deliberately take away bone and convert cavity into saucer-like shape which is easier to get mucosa to collapse down over.
- Pack cavity with materials: patients own bone (autograft) or bone you can buy in (allograft from another human or xenograft from another species), induce bony infill by this technique.
- Layered soft tissue closure: suture layers of muscle into area. This is not a commonly use technique.
- Secondary intention: pack defect usually with some form of antiseptic dressing to encourage healing by secondary intention. This is long drawn out process for the patient involving several visits. Can be very uncomfortable for patient.
What are the advantages of ENUCLEATION?
- Complete removal for histology
- Cavity heals without complications
What are the disadvantages of ENUCLEATION?
- Infection
- Incomplete removal of lining
- Damages to adjacent teeth or antrum on attempt to remove lining
- Weakening of bone (risk of pathological fracture)
Define, creation of a pouch through connection of flap to the remaining cyst lining to allow shrinkage of the lesion which may become self-cleansing or be subsequently removed.
MARSUPIALISATION
What is the tx of choice for cases of eruption cysts involving potentially useful teeth, very large cysts, or a cyst in an older more frail patient.
MARSUPIALISATION
What is the main difference between surgical technique for MARSUPIALISATION and ENUCLEATION?
For MARSUPIALISATION, the flap margins should rest directly over area where you are going to complete the osteotomy. Whereas in ENUCLEATION, flap margins should be distant from osteotomy site.
Why is an acrylic bung used after MARSUPIALISATION?
To stop food debris from getting caught in the wound
What are the advantages of MARSUPIALISATION?
- Avoids pathological fracture
- Most suitable for tx for medically compromised patients
- Avoids damage to adjacent structures
- Allows potentially useful teeth to erupt
What are the disadvantages of MARSUPIALISATION?
- Potential for cyst to reform once orifice closes
- Repeat visits (prolonged tx)
- Manual dexterity and compliance required
- Complete lining not available for histology (only small part of lining sampled)
Define,
“the procedure which reduces the pressure within the cyst cavity, the opening into the cyst has to be kept open with a drain.”
Decompression
Why are Odontogenic keratocysts difficult to enucleate in their entirety?
Due to thin lining and daughter cysts
What procedure may reduce likelihood of recurrence of OKC after ENUCLEATION?
Curettage
What radiographic sign might indicate a lesion has a greater potential for it being an odontogenic tumour rather than a simple cyst?
Root resorption of surrounding teeth
What two cysts are most likely associated with vital teeth?
- Lateral periodntal cyst
- Gingival cyst
Why is nasopalatine cyst often a heart shaped radiolucency?
This is because cyst has formed on either side of incisive foramen
What are clinical signs of nasolabial cyst?
- Fullness of cheek in area
- Elevation of base of nose
Define, a well demarcated, unilocular developmental anomaly below the level of IAN canal.
Staphne’s defect
What cysts are the most likely diagnosis if there is a large radiolucency arching up between roots of teeth on radiograph?
Bone cysts
- either aneurysmal or solitary Haemorrhagic
What is the management for AMELOBLASTOMA?
En block resection
What is en block resection?
Removal of lesion along with border of normal bone
A 34 year old patient attends complaining of food packing around an only just visible lower right third molar tooth. You take DPT and this shows a well circumscribed unilocular radiolucency around a horizontally impacted tooth 48.
Give 3 pathological lesions that can cause this radiograohic appearance.
Dentigerous cyst
OKC
AMELOBLASTOMA
A 34 year old patient attends complaining of food packing around an only just visible lower right third molar tooth. You take DPT and this shows a well circumscribed unilocular radiolucency around a horizontally impacted tooth 48.
Give 3 treatment options for the management of such a lesion.
Enucleation
MARSUPIALISATION
En block resection
A 34 year old patient attends complaining of food packing around an only just visible lower right third molar tooth. You take DPT and this shows a well circumscribed unilocular radiolucency around a horizontally impacted tooth 48.
Give an advantage and a disadvantage of each of the treatment options: ENUCLEATION, MARSUPIALISATION, en block resection.
Enucleation:
A= eliminates tissue in its entirety
D= large potential for post-op bleeding and infection due to extensive dead space, risk to IAN sensation, requires GA for procedure.
MARSUPIALISATION:
A= can be carried out under LA, less invasive for patient
D= you only harvest small amount of cyst lining
En block resection:
A= eliminates pathology in entirety
D= very invasive, requires a lot of reconstruction, can be disfiguring for patient, also nerves sacrificed so patient would have permanent numbness of lower lip.
A 34 year old patient attends complaining of food packing around an only just visible lower right third molar tooth. You take DPT and this shows a well circumscribed unilocular radiolucency around a horizontally impacted tooth 48.
Give 2 sequelae if no treatment is carried out?
- Expansion of cyst to involve more of mucosa/bone and oral cavity + infection
- Increase in size of lesion predisposes bone to pathological fracture
A 54 year old man attends for replacement of an MCC crown on tooth 11 as it is cracked and he is unhappy with the appearance. You take a periapical film and find this endodontically treated post crowned tooth has a 1cm unilocular cyst like radiolucency associated with the apex of the tooth.
What is the mist likely diagnosis?
A radicular cyst
A 54 year old man attends for replacement of an MCC crown on tooth 11 as it is cracked and he is unhappy with the appearance. You take a periapical film and find this endodontically treated post crowned tooth has a 4mm unilocular cyst like radiolucency associated with the apex of the tooth.
What is the likely diagnosis?
A periapical granuloma (any lesion <6mm is unlikely to be cyst)
A 54 year old man attends for replacement of an MCC crown on tooth 11 as it is cracked and he is unhappy with the appearance. You take a periapical film and find this endodontically treated post crowned tooth has a 3cm heart-shaped unilocular cyst like radiolucency associated with the apex of this tooth and tooth 21.
What is the likely diagnosis?
Nasopalatine cyst
A 56 year old female patient has been having pain from her partially erupted LL8. You take a DPT which shows a 2cm unilocular radiolucency associated with the non-carious crown of the LL8.
What is the most likely diagnosis?
A dentigerous cyst
A 56 year old female patient has been having pain from her partially erupted LL8. You take a DPT which shows a 2cm multilocular radiolucency which includes the LL8.
What is the most likely diagnosis?
OKC
A 56 year old female patient has been having pain from her partially erupted LL8. You take a DPT which shows a 2cm multilocular radiolucency which includes the LL8 and there is root resorption of the LL6 and LL7.
What is the most likely diagnosis?
An AMELOBLASTOMA
A 57 year old man attends with a discharging sinus associated with a post-crowned tooth 11. You take a PA film which shows a 12mm unilocular radiolucency associated with the apex of this tooth. He is keen to save the tooth. How would this be managed?
Enucleation of the lesion and peri-radicular surgery of tooth 11
A frail 94 year old attends with pain and swelling from an area on the lower right mandible. There is pus discharging intra-orally and a DPT show a 6cm residual cyst in the angle of the mandible. How could this be managed?
Decompression
(MARSUPIALISATION may involve too much patient involvement to keep clean which might make not make it best option in this scenario)
Define,
“A prosthetic device of alloplastic material implanted into the oral tissues beneath the mucosa and/or periosteal later, and/or within the bone to provide retention and support for a fixed or a removable prosthesis.”
A dental implant
What are the indications for placing an implant?
- Single tooth replacement
- Multiple teeth replacement (implant retained fixed bridge)
- Full arches (implant retained dentures)
What are the advantages of implants?
- Function
- Aesthetics
- Quality of life
What are the patient factors required in order for implant placement to be appropriate on NHS?
- Well motivated patients
- Well maintained dentition free of caries and periodontally sound
- Systemically well/ not immunocompromised
- Non-smoker (no nicotine for at least 3 months)
- Not a bruxist
- No impaired wound healing
What are the 10 medical contraindications to having implants placed?
- Poorly controlled diabetes (HBA1c >8)
- Bisphosphonate treatment (especially IV)
- Psychiatric and mental health issues
- Blood disorders
- Immunodeficiency
- Alcohol/drug abuse
- Bone disorders
- Epilepsy
- Tobacco use
- Poor dental health
What 6 patient groups can get an implant on the NHS?
- Patients with congenital, inherited conditions that have lead to missing teeth, tooth loss or malformed teeth
- Patients with traumatic events leading to tooth loss
- Patients with surgical interventions resulting in tooth and tissue loss (e.g. H+N cancer and non-malignant pathology)
- Patient who are edentulous in either one jaw or both in whom repeated conventional denture treatment options have been unsuccessful
- Patients with severe oral mucosal disorders, or severe xerostomia where conventional prosthetic treatment is not possible.
- Patients who do not have suitable existing teeth that can be used for anchorage to facilitate orthodontic treatment
What are the 5 requirements of an implant in order for it to be safe to use?
- biocompatible at a biological level
- bio-mechanically compatible with physiological forces of mastication and speech
- Morphologically of dimensions easily applied to oral cavity and facilitate development of structure on top (e.g. crown, denture or bridge)
- MRI safe (cannot magnetise)
- Good image compatibility (so you can easily discern between different components used in implant systems)
Define,
“The direct structural and functional connection between ordered living bone and the surface of a load-carrying implant”.
Osseointegration
What are three host factors affecting osseointegration?
- Bone density
- Bone volume and bone implant surface area
- Parafunctional habits
What are 4 implant factors affecting osseointegration?
- Implant macro design
- Chemical composition and biocompatibility
- Use of surface treatment and coatings
- Implant titling, prosthetic passive fit, cantilever, crown height, occlusal table, loading time
What is the advantage of using surface treatments/coatings on implants?
May improve osseointegration
What 5 factors may improve osseointegration?
- Surface chemical composition
- biocompatibility
- high corrosion resistance
- Hydrophilicity
- Roughness (e.g. titanium plasma spaying, grit blasting, acid etching, calcium phosphate coating)
What two metals are used in implants because they are the only metals that do not inhibit the growth of osteoblasts?
- Type 4 titanium alloy
- Zirconium
According to the royal college guidelines which of the following patients would NOT be suitable for dental implants on the NHS?
A. An 85 year-old man with an atrophic mandible with COPD
B. A 69 year old woman with a profound gag reflex who has RA
C. A healthy 17 year old professional rugby player who knocked out tooth 11
D. A 23 year old patient who has a non-vital tooth 11 and wants an implant
E. A 45 year old patient who had teeth removed as part of his treatment for oropharyngeal cancer
D. A 23 year old patient who has a non-vital tooth 11 and wants an implant
Which of these conditions is NOT a contraindication to dental implants on the NHS?
A. A diabetic patient with HBA1c of 12
B. A patient with myeloma on IV bisphosphonates
C. A smoker who sopped 6 months ago and started using a nicotine containing vape
D. A patient with Sjögren’s syndrome
E. A patient with extreme bruxism
D. A patient with Sjögren’s syndrome
What factor is NOT considered important for osseointegration?
A. Biocompatibility
B. MRI safe
C. Bone volume
D. Surface modification
E. Angulation of implant loading
B. MRI safe
What is the minimum width and ideal height required for bone volume prior to implant placement?
Minimum of 7mm in width, ideally at least 1cm in height.
What angulation does loading of implant need to be?
Axial (down long axis)
What are the two key patient related factors when assessing suitability for implants?
- Oral hygiene
- Compliance
What are the four key patient medical factors when assessing suitability for implants?
- Medical fitness
- Medication
- Radiation treatment
- Growth
What are the four key site related factors when assessing suitability for implants?
- Periodontal status
- Access
- Pathology near implant site
- Previous surgeries at the site
What are the three key surgical complexity factors when assessing suitability for implants?
- Timing of implant placement
- Simultaneous or staged grafting procedures
- Number of implants
Why is H+N radiotherapy a relative contraindication and not an absolute contraindication?
Because if a patient has undergone H+N radiotherapy involving <50 Gy (gray) total dose of radiotherapy to the target area then the risk of implant failure tends to be reduced
What are the three different timeframes that implants can be placed in?
- Immediately after tooth is extracted (immediate implant)
- Between 6-8 weeks after extraction (delayed immediate implant)
- Anything beyond 12 weeks to 6 months is delayed implant placement.
What are the anatomical factors in patient assessment for implants?
- Bone volume horizontally and vertically
- Soft tissue quality/thickness/biotype
- Proximity to vital structures (e.g. maxillary sinus, IAN canal and mental foramen)
- Papillae, recession, interproximal attachment
- Aesthetic risk assessment
What is better for implant placement, a thick or thin soft tissue biotype?
Thick biotype, as mucosa is keratinised.
Why is keratinised mucosa more advantageous for implant placement?
It is resistant to the forces required to clean around the area of the implant. It can withstand mechanical trauma associated with OH measures.
How does non-keratinised mucosa (thin biotype) put patients at an increased risk of implant mucositis and peri-implantitis?
It becomes painful for patients to perform adequate OH.
What is the ideal length of an implant?
8-10mm
How many classes of bone quality are there?
4
Where in the jaw are you most likely to find class 1 and 2 bone?
mandible
(Class 1 most often in anterior mandible)
Describe class 1 bone?
Consists almost exclusively of cortical bone (very dense)
Describe class 2 bone?
Consists of mostly cortical bone but with an increasing amount of trabecular bone
Describe class 3 and 4 bone?
Consists nearly exclusively of trabecular bone
Describe where in the jaw you would find class 3 and 4 bone?
Mostly in the maxilla
What is the importance of class 1 and 2 bone for implant placement?
This bone gives very good primary stability, so as soon as you place the implant in it gives very good friction fit, so there is no mobility of the implant, it is very stable.
What is the disadvantage of class 3 and 4 bone for implant placement?
It is very spongey and less stable. Problem with instability is it can lead to fibrous encapsulation (formation of scar tissue on the surface of the biomaterial) which will lead to failure of your implant.
Why can an implant have a period of instability a few weeks after placement?
Due to a period of remodelling within the bone, then it will start to osseointegrate and gain stability.
With class 1-3 bone, how long do you have to wait for stability in order to start restoring your implant?
6 weeks
With class 4 bone, how long do you have to wait for stability in order to start restoring your implant?
12 weeks (takes longer for good stability)
Imaging is important in implant planning. What three things should you capture in photographs?
- Document resting lip line and smiling lip line
- Position of midline’s (look for evidence of gingival recession or loss of papillary tips)
- Occlusion
Imaging is important in implant planning. What three types of radiograohs should be considered?
- PA
- DPT
- CBCT (with radiographic stents to mark for ideal position of implants)
What is a “safety zone” in regards to positioning of IAN canal and mental foramen when implant planning?
A zone that takes into account that the coronal aspect of the mental foramen is 2mm above the IAN canal/ mental nerve.
When considering dimensions of the alveolus, what is the minimal distance (in mm) from the implant shoulder to the adjacent tooth at bone level (mesial and distal)?
1.5mm
When considering dimensions of the alveolus, what is the minimal distance (in mm) between two adjacent implant shoulders (mesiodistal)?
3mm
When considering dimensions of the alveolus, what is the minimal distance (in mm) required between two adjacent implants from the centre of each implant?
7mm
What 3 procedures can be undertaken to change bone levels prior to implant placement?
- Recontouring
- Grafting bone
- Sinus lift techniques
A 24 year old male patient attends with congenital hypodontia, missing his lateral incisors. His adhesive bridges keep debonding and he would like a fixed solution like implants. You assess him clinically and there is 4mm of bone between the central incisor and the canine and a width of 3mm. He has a thin biotype and there is evidence of caries in the premolar and molars. He admits to being dentally anxious and not a good attender. How would you manage this patient?
A. Refer him to secondary care as he fits the college guidelines due to hypodontia
B. Advise him that with active disease he does not fit the indications so you would want to get him disease free before considering referral to secondary care
C. Refer him to orthodontics as you think he will need space created to allow implant placement
D. Ask for an informal opinion from a psychologist about managing his anxiety
E. His case is so complex it would not be treated in secodnary care
B. Advise him that with active disease he does not fit the indications so you would want to get him disease free before considering referral to secondary care
A 67 year old woman presents to you in primary care with 50 year old dentures complaining that her lower denture is so loose that she cannot wear it. She has well controlled type II diabetes and COPD controlled with salbutamol, montelukast and prednisolone but she still smoked 15 cigarettes per day. She has heard about implants and asks whether she could be referred for these. How would you manage this patient?
A. Attempt to make new well fitted and extended dentures to see if she can cope with these
B. Refer her to secondary care for consideration for implants
C. Tell her that because of her health issues she is not suitable for implants
D. Advise her that she does fit the royal college guidelines so you cannot refer her to secondary care
E. Reline her lower denture to see if that improves the fit
A. Attempt to make new well fitted and extended dentures to see if she can cope with these
A 52 year old man attends with a failing post crown in tooth 11. The tooth was damaged 20 years previously when playing football and had endodontic tx and now the post keeps falling out. He would like an implant but can’t afford the private fee. He stopped smoking one month ago and is using a nicotine containing vape. You notice that he has grade II mobility in all his anterior maxillary teeth and PA films show periodontal bone loss. How would you manage this patient?
A. Treat his periodontal disease and once it is stable refer for an implant opinion
B. Treat his periodontal disease, extract tooth 11 and provide a denture and refer for an opinion on an implant
C. Explain that he does not fit the criteria for implants on the NHS but does need the tooth 11 treated possibly with a replacement post-crown or extraction and will need his periodontal condition treated and encouraged to stop using nicotine containing products like vapes
D. Recommend extraction of tooth 11 and a bridge
E. Recommend extraction and a partial denture
C. Explain that he does not fit the criteria for implants on the NHS but does need the tooth 11 treated possibly with a replacement post-crown or extraction and will need his periodontal condition treated and encouraged to stop using nicotine containing products like vapes
Which of these factors is an absolute contraindication to dental implants on the NHS?
A. Patient who has just started oral bisphosphonates
B. Patients with radiotherapy for oropharyngeal cancer
C. Patients who smoke
D. Patients with well controlled diabetes
E. Patients with xerostomia
C. Patients who smoke
Which of these clinical factors can have the most significant negative impact on implant survival?
A. A thin bio-type
B. A knife edge ridge
C. A labial undercut
D. Recession of the adjacent teeth
E. Limited access for surgery
A. A thin bio-type
What are the two different types of dental implants?
- Tissue level implants
- Bone level implants
What type of implants are used under dentures?
Tissue level implants
Anywhere in the mouth where aesthetics is really important, what type of implant should be used and why?
Bone level implants, as they sit level with bone so does not show.
What forces do implants not deal well with?
Tensile and shearing forces
What are tensile forces on an implant?
Tilting forces
What are shearing forces on an implant?
Rotatory forces
What are the 4 different timings of implant surgery?
- Immediate
- Immediate delayed
- Delayed
- Elective
What type of implant surgery is described?
Tooth is taken out at the same time implant is inserted into socket.
Immediate implant surgery
What type of implant surgery is described?
Early soft tissue healing within 4-8 weeks
Immediate delayed implant surgery
What type of implant surgery is described?
Partial bone healing in 3-4 months
Delayed implant surgery
What type of implant surgery is described?
Full bone healing takes >4 months. Used for edentulous arches.
Elective implant surgery
What are the 5 main complications that can arise with implants?
- wound breakdown
- Infection
- Early loss
- Mucositis
- Peri-implantitis
What are the success rates for implants over 9-10 years according to literature?
> 90%
What situations would mean an implant has reached failure in that it won’t osseointegrate correctly?
- If lost
- If mobile
- If it shows peri-implant bone loss <1mm in first year or >2mm a year after
What can you prescribe to pt with wound dehiscence following implant placement?
Prescribe then a topical Chlorohexidine gel to apply 2x daily and this will help it to heal.
How much bone width is the minimum required to place a standard dental implant?
7mm
What is the minimum distance between teeth that is sufficient to place a dental implant?
7mm
When placing an immediate delayed implant, how many weeks do you wait after the tooth is extracted?
4-8 weeks
When doing surgery for dental implants, which of the following has the greatest impact on the outcome of surgery?
A. Atraumatic handling of soft tissue
B. Using refrigerated saline to irrigate the drill
C. Using antibiotic cover
D. Using a profile drill for a coronal flare
E. Ensuring primary closure of the flap
B. Using refrigerated saline to irrigate the drill
When would you use tissue level implants rather than bone level implants?
When planning for a denture
