BAD SPLITS AFTER ORTHOGNATHIC SURGERY

1. BAD SPLITS IN BSSO
DR JAMEEL KIFAYATULLAH
Lecturer Khyber College of dentistry Peshawar
PAKISTAN

2. BAD SPLITS
• An unfavourable and unanticipated pattern of
the mandibular osteotomy fracture is
generally referred to as a ‘bad split’

3. Causes and risk factors of bad splits
• Lack of cancellous bone between the two cortical
bone layers in ascending ramus makes the split more
difficult and hinders exact separation of cortical and
cancellous bone.
• inadequate vertical osteotomy at the inferior border
• horizontal osteotomy performed too high above the lingula
• exertion of excess force when separating the proximal and
distal segments
• impacted third molars.
There is much controversy among scholars regarding
whether impacted teeth should be extracted 6-9 months
before SSRO or at the same time as SSRO.

4. CONSEQUENCES OF BAD SPLIT
Bad splits may cause
• mechanical instability,
• a disturbance in bony union
• lead to bone sequestration with subsequent
infection

5. Prevention of bad splits
Prevention is focussed on
• adequate osteotomy design,
• eliminating sharp angle where abnormal
stress occurs on bony segments
• completion of adequate cuts into the
retrolingular depression and through the
inferior border
• careful separation of the segment.

6. BUCCAL PLATE FRACTURE,PARTIAL
• Shearing off of the
fragment from lateral
aspect of proximal
segment
• Cause: inadequate bone
cut at the inferior
border of the lateral
vertical osteotomy

7. Treatment
• The split completed at the
inferior border
• Separate the proximal and
distal segments with gentle
manipultion
• Rigid fixation (plate) used to
stabilise the free fragment
to the proximal segment
• Then bicortical fixation of
SSO
A four-hole or larger plate is used to stabilize the free
fragment to the proximal segment. Additional bicortical
screws are placed to ensure stability of the complex

8. BUCCAL PLATE FRACTURE COMPLETE
• When the fragment
occurs more superiorly
• Condyle and coronoid
are in the same
proximal fragment
• The proximal fragment
has a high or horizontal
fracture

9. BUCCAL PLATE FRACTURE COMPLETE
• The large fragment that
was sheared off should
have a plate placed on
it outside the mouth. It
should be re-inserted
and connected to the
proximal segment(two
percutaneous incisions)
• Then Fixation of SSO
with bicortical screws

10. Subcondylar fracture( buccal plate)
• Condylar fragement
separated from proximal
segment
• coronoid and angle in a
separate fragment
• The condyle must be rigidly
fixated to proximal segment
to create a single proximal
segment( percutaneous
incisions)
• Proximal and distal
segments stabilised with
bicortical screws
• Correct condylar positioning
difficult to achieve
• A plate is used on the condylar segment with
additional screws placed to stabilize the free
fragment to the distal segment

11. Lingual plate fracture
• Prevention:remove
impacted third molars
atleast 9 months before
surgery
• When an unwanted
fracture occurs, the split
must be completed along
the original planned
osteotomy lines because
the free lingual segment
doesnot obstruct the
osteotomy.
A lingual split (distal segment) has occurred
in the third molar region

12. LINGUAL PLATE FRACTURE
• The distal segment is
placed into occlusion.
• The free fragment is
manipulated to an
anterior position and is
fixed to the proximal
segment by one or more
bicortical screws.
• monocortical plate
placed across proximal
and distal segments for
stabilization
• Two bicortical screws are used to stabilize the free
segment to the proximal seg-ment. A plate can be
used tostabilize the proximal segment to the distal
fragment.

13. BUCCAL PLATE SPLITS
• Type 1: Proximal seg-
ment (buccal) fractures
type 1A, small anterior;
1B= vertical
1C= angle
1D= horizontal ramal;
1E= oblique ramal
1F=inferior border).

14. TYPE 1A TREATMENT
Small segments that
have been stripped
from the periosteum
(e.g., type 1A fractures)
may be removed to
prevent sequestration.9

15. TYPES 1B,1C,1E,1F TREATMENT
• Larger fractured
fragments (e.g., types
1B, 1C, 1E, and 1F) with
an intact periosteum
are best secured
immediately, and simply
and quickly reduced
with plate
osteosynthesis,

16. TYPE 1D(HORIZONTAL RAMAL)
• If the fractured buccal
fracture line runs above the
lingula (type 1D), the
condylar segment is entirely
free. Securing its position in
the fossa requires securing
the condylar stump to the
remaining buccal cortex.12
In this situation, additional
removal of the coronoid
process to eliminate
traction of the temporalis
muscle may be necessary
HORIZONTAL RAMAL

17. LINGUAL PLATE FRACTURES
• Type 2: Distal segment
(lingual) fractures
type 2A= vertical
type 2B= horizontal

18. Lingual plate fractures vertical
• In the case of a vertical
fracture (type 2A), the split
can be completed and the
lingual plate will remain
unattached; fixation can
only be accomplished with
buccal plating and
monocortical screws. If
desired, the lingual
fragment can be fixed with
one or two bicortical
screws. If align-ment is
accomplished, fixation does
not appear to be necessary
in all cases

19. Lingual plate fractures Horizontal
• In the case of a horizontal
fracture (type 2B), the
situation does not hamper
the surgery, and fixation can
still be accomplished within
the same surgical session
with plate osteo-synthesis
or upper border bicortical
screws. Lower border
bicortical screws will not fix
the two major fragments
but might fix the lingual
fragment if desired.

20. Coronoid and condylar process fractures
• Type 3=Coronoid
process fractures.
• Type 4: Condylar neck
fractures.

21. Type 3: Coronoid process fractures
These fractures
probably result from
incorrect positioning of
the bone-cuts. In this
type of fracture, the
free coronoid may be
left in place without
consequences.

22. TYPE 4 CONDYLAR NECK FRACTURES
Incorrect positioning of
the bone-cuts most likely plays a role
in their occurrence as well.
This type of bad split may be the
most difficult to reduce, especially if
the condyle remains attached to the
distal tooth-bearing segment. In the
latter case, a low osteotomy may be
necessary. This type of fracture is
best managed by aligning the bony
fragments and semi-rigid plating. This
may be a difficult procedure,
necessitating routines in open
reduction and internal fixation in
condylar fracture treatment and
transcutaneous access. Discontinuing
the procedure and a secondary
attempt after consolidation may be
the best choice.

23. Bilateral bad splits
If both splits occur in undesired patterns,
bilateral salvage may be attempted. However
it may be best to discontinue the surgery,
especially if operator experience is
limited.After consolidation for 6 months, re-
operation may be considered.