Oral Surgery and Orthodontic Interface Flashcards
What are the soft tissue surgeries that may be done to aid orthodontics?
Frenectomy
-> V to Y frenoplasty
-> Z-plasty
Impacted canines
-> Buccal apically repositioned flap
-> Palatal open exposure
Impacted premolar exposures (more often require only soft tissue procedure)
What are the hard tissue surgeries that may be done to aid orthodontics?
Impacted canines
-> Buccal apically repositioned flap with bone removal
-> Palatal open exposure with bone removal
-> Buccal or palatal closed exposure with gold chain attachment
-> Extraction
Premolars
-> Extraction
-> Exposure of impacted premolars with bone removal
Other extractions
Submerged retained deciduous teeth
Implants
Mini-implants
Orthognatic surgery
What are the treatment options for impacted canines?
Leave- if tooth not damaging other teeth, if not affecting ortho tx, if reasonable aesthetics, patient not keen on surgery, if no associated pathology
Extract- reasonable aesthetics without, poor position of canine (may allow easier tooth movement)
Expose- encourage improvement in position
Transplant- take it out and place into correct position (uncommon in UK)
What are the risks of leaving impacted canines?
Infection
Future eruption
Dentigerous follicular cysts
What can be done to the premolars if canines are impacted and left/extracted?
Can be moved into position of canine and made to look like canine
What can happen to laterals and premolars if canines are impacted?
Drifting
Rotation
What is the procedure for minimal exposure of an impacted canine if it is close to the surface?
Remove primary tooth
Excise soft tissue and follicle with 15 scalpel
Remove bone with mongeurs
Place dressing and suture with silk
Provides environment for canine to erupt naturally (if it erupts into abnormal position- usually palatally, it can be fixed with ortho)
When may autotransplantation of an impacted canine be considered?
If it would damage teeth on way down
If distance is too far
*Must be careful not to damage tooth in extraction phase
What are the steps in autotransplantation?
Raise flap
Extract canine gently- try not to damage PDL
Store in milk or saline- aim to have out mouth for least amount of time possible
Remove deciduous tooth
Trim bone to allow canine to fit (may require some trial and error)
Fit canine- will be unstable so splint with titanium trauma splint or SS wire on one tooth either side (must be semi-rigid- to prevent risk of ankylosis etc)
Lost bone may or may not regenerate
Transplanted tooth will eventually ankylose- failure can be difficult to remove
How can risk of ankylosis in autotransplantation be reduced?
Do 3d scan of patient
-> make 3d model of tooth and produce Co/cr replica as model used to prepare bone and produce custom socket for real tooth
EXPENSIVE- implant may be better option
What are the issues with buccally placed canines?
Easier access for OS (more difficult for ortho- poor aesthetics)
Cannot cut hole like you would on palate as tooth would erupt through unattached mucosa (would lose attached mucosa)
How is a buccally placed canine surgically exposed?
Apically repositioned flap- 3-sided full thickness flap with more parallel relieving incisions
-> Tissue is reflected and sutured apically at cervical margin, when canine erupts it brings attached mucosa
-> nice aesthetics and easier maintenance
Why is it important to look at radiographs before carrying out surgery on impacted canines?
We can look at space available to allow eruption of canines
Can show us teeth which are not worth exposing- dilacerated etc
What is the most common reason for impacted second premolars?
Premature loss of e
-> drift of 4 distally and 6 buccally, resulting in loss of space for 5 (may fail to erupt or erupt lingually/buccally)
What are kissing canines?
One canine may come across midline and sit against opposite canine
-> seen on radiograph (require parallax to locate exact position)
What are the treatment options for kissing canines?
Tooth crossing midline must be left, extracted or transplanted (ortho will not be possible)
What are the steps in using a gold chain to align impacted canines?
Lift flap of gum to expose canine- drilling may be required
Acid etch and bond composite to palatally placed tooth (attach chain via button/mesh)
Chain hangs down and can be attached to appliance and force applied to pull it into position
Closed exposure- put flap back
Open exposure- lift flap, drill away bone, cut hole in gum so you can see canine
What are the issues with ankylosed deciduous teeth?
Very difficult to remove- no space to extract normally
Impedes eruption of other teeth
Requires flap/sectioning (careful when drilling so not to damage unerupted tooth)
Risk of pushing tooth into sinus
What were frenectomies used for historically?
To remove thick fibrous frenums which were associated with midline diastema
What were the steps in a frenectomy?
Numb patient
Hold with forceps and cut out with 15 blade
-> Creates large defect- place resorbable suture and dressing if required
What is done in a V to Y frenoplasty?
V shaped incision
Close sutures on line parts of triangular defect
Gives y shaped scar and less prominent frenum
What is done in a Z-frenoplasty?
*Very uncommon
Incision in shape of Z
Switch places on points of z and suture in place to reduce prominence of frenum
What are the ideal features of using implants for anchorage in orthodontics?
Patient compliance unnecessary
Absolute anchorage as there is no periodontal ligament
Easily used under a variety of treatment modalities
Easily placed
Removable, if necessary
What are mini-implants? (TADs)
Screws made of SS
-> not titanium to prevent osteointegration
Placed by orthodontists for complex cases
-> allows for attachment of elastics to move teeth without compromising anchorage
What are the steps in placing a mini-implant?
Check radiograph to check where roots are (prevent damage)
Punch hole into mucosa through papilla
Tap screw into bone until only stud is showing
Elastics are then used to move teeth
What is different about a palatal mini-implant?
Takes more surgical skill- palatal implant is attached to another screw
Screws are longer- must be angled carefully to avoid structures
Use lateral cephs to determine angle and amount of bone
What are the advantages of palatal mini-implants?
Stable as in firm bit of bone in midline of palate
Prevents need for patient to wear head gear
-> attach screw to molars via SS bands (teeth can move back without compromising anchorage)
Why may a corticotemy be carried out?
To speed up tooth movement through dense bone
-> if other methods have failed
-> can be helpful for intruded teeth which have occurred due to trauma
What is done in a corticotemy?
Drill U-shaped gutter and small grooves into buccal and palatal bone to weaken bone in certain areas to encourage tooth eruption
*care not to damage erupting tooth itself
