Transcript Bone Loss and Patterns of Bone Destruction

Management of periodontal defects
(A) Periodontal bony defects ( classification etc. )
(B) Resective osseous surgery
Ren-Yeong Huang DDS PhD
(A) Periodontal bony defects
Horizontal bone loss
Bone deformities (osseous defects)
*vertical, angular defect
*osseous crater
*bulbous bone contour
*reverse architecture
*ledge
*furcation involvement
(A) Periodontal bony defects
Horizontal bone loss
CEJ-Alveolar Crest (Parallel)
(A) Periodontal bony defects
Angular bony defect
CEJ-Alveolar Crest (X Parallel)
(A) Periodontal bony defects
angular bony defect
(A) Periodontal bony defects
Angular bony defect
(A) Periodontal bony defects
Osseous crater
(A) Periodontal bony defects
bulbous bone contour
(A) Periodontal bony defects
Reverse architecture
(A) Periodontal bony defects
Ledge
(A) Periodontal bony defects
Furcation involvement
(A) Periodontal bony defects
Furcation involvement
(B) Resective Osseous Surgery
Osseous surgery
the procedure by which changes in the
alveolar bone can be accomplished to rid
it of deformities induced by the
periodontal disease or other related
factors, such as exostoses and tooth
supra-eruption
(B) Resective Osseous Surgery
Osseous surgery
*addictive (reconstructive)
restoring the alveolar bone to its original
level
*subtractive (resective)
restoring the form of the pre-existing
alveolar bone to the level present at the
time of the surgery or slightly apical to this
level
(B) Resective Osseous Surgery
Osseous surgery
*subtractive
*addictive
(B) Resective Osseous Surgery
Selection of treatment technique
1-wall
2-wall
wide
shallow
recontoured
3-wall
narrow
deep
reconsturcted
(B) Resective Osseous Surgery
Rationale
*goal:
1.to reshape the marginal bone to resemble that of
the alveolar process undamaged by periodontal
disease (the purest, surest and most predictable
method for reducing pockets with bony discrepancies)
2.to enhance the patient’s ability to remove plaque
and oral debris
3.to achieve more effective maintenance therapy and
greater longitudinal stability
(B) Resective Osseous Surgery
Normal alveolar bone morphology
1.the interproximal bone is more coronal in
position than the labial or lingual bone and
pyramidal in form
2.the form of the interdental bone is a
function of the tooth form and the embrasure
width (ex: the more tapered the tooth, the
more pyramidal is the bony form; the wider
the embrassure, the more flattened is the
interdental bone)
(B) Resective Osseous Surgery
Normal alveolar bone morphology
3.the postion of the bony margin mimics the
contour of the CEJ. less “scalloping” and a
more flat profile in the posterior than the
anterior region
(B) Resective Osseous Surgery
Normal alveolar bone morphology
(B) Resective Osseous Surgery
Terminology: for procedures
*ostectomy:
reshaping the bone including removal
of tooth-supporting bone
*osteoplasty:
reshaping the bone without removal of
tooth-supporting bone
(B) Resective Osseous Surgery
Terminology: for bone form
*positive architecture:
radicular bone apical to interdental bone
*negative (reverse) architecture:
interdental bone apical to radicular bone
*flat architecture:
interdental bone equal to radicular bone
*ideal osseous form:
interproximal bone coronal to facial & lingual bone
similar interdental bone level
gradual slope
(B) Resective Osseous Surgery
Terminology:
*positive
architecture
*flat architecture
*negative (reverse)
architecture
(B) Resective Osseous Surgery
Terminology: ideal osseous form
(B) Resective Osseous Surgery
Terminology:
for the thoroughness of the osseous reshaping technique
express the expected therapeutic result
*definitive osseous reshaping:
further reshaping would not improve the
overall result
*compromised osseous reshaping:
a bone pattern can’t be improved without
significant osseous removal that would be
detrimental to overall result
(B) Resective Osseous Surgery
Factors in selection of resective
osseous surgery
the relationship between the depth and configuration
of the bony lesions to the root morphology and the
adjacent teeth determines the extent that bone and
attachment is removed during surgery
*candidate:
1 or 2-wall bony defect
early to moderate bone loss (2-3mm)
moderate-length root trunk
(B) Resective Osseous Surgery
Effects of osseous resective surgery
*bone resorption: mean 0.6mm in 1st year
*loss of attachment
*pocket depth reduction
*mobility increased, especially after
removal of inter-proximal bone
(recovery after 1 year)
(B) Resective Osseous Surgery
 Indications
*shallow intra-bony defect around a tooth
with sufficient periodontal support
*existence of non-supporting bone that could
affect a periodontal pocket or that hinders
close adaptation of flap (thick alveolar
bone margin, shelf-like bone, exostoses,
inter-dental crater and thick alveolar bone
walls around the intra-bony defect)
(B) Resective Osseous Surgery
Indications
*Class I or II furcation involvement
*residual osseous defect remaining
after regenerative procedures
*irregularity of bone morphology
related to hemisection and root
resection
*clinical crown requires lengthening
before restorative or prosthetic
treatment
(B) Resective Osseous Surgery
Contra-indications
*insufficient periodontal support:
--a periodontal pocket of more than
8mm exists after initial therapy
--deep intra-bony defect is more than
3-4mm
--the bottom or the osseous defect is
more than half of the root length
from the CEJ
(B) Resective Osseous Surgery
Contra-indications
*anatomic limitation (external oblique
ridge, mental foramen & maxillary
sinus)
*esthetic limitation
*extended tooth mobility
*if alternative therapy would be more
effective
(B) Resective Osseous Surgery
 Advantages:
*reliable
*short term (812weeks)
*obtain gingivo-alveolar
bone morphology
that facilitate easy
maintenance
 Disadvantages:
*attachment loss
*root exposure,
compromising
esthetics
*possibility of
hypersensitivity
*possibility of root
surface caries
*possibility of
phonetic impediment
(B) Resective Osseous Surgery
Considerations before osseous resection
*Is the root length and shape adequate?
*Will the amount of residual supporting bone
be adequate after osseous resection?
*How much periodontal support might be lost
from the adjacent teeth?
(B) Resective Osseous Surgery
Considerations before osseous resection
*Is there a possibility of increased tooth
mobility due to decreased tissue support?
*Are caries a risk?
*Would furcations and root grooves be
exposed?
(B) Resective Osseous Surgery
Examination and treatment planning
*probing:
1.pocket depth
2.the location of the base of the pocket
relative to MGJ
3.the numbers of the bony walls
4.furcation defects
*sounding: bony topography
(B) Resective Osseous Surgery
Examination and treatment planning
*radiograph:
1.interproximal bone loss
2.angular bone loss
3.caries
4.root trunk length
5.root morphology
(B) Resective Osseous Surgery
Examination and treatment planning
*re-evaluation: after OHI, Sc & RP
1.response to the therapy
2.patient’s compliance
(B) Resective Osseous Surgery
Examination and treatment planning
1.good supragingival plaque control and
residual pocket depth ≧5mm
Surgery
2.surgery also can help:
*caries to be restored
*fractured roots or abutment to be removed
*bony exostoses, ridge deformities to be
recontoured
*short anatomic crown to be lengthened
(B) Resective Osseous Surgery
Osseous resection techniques
*instruments:
ostectomy: hand (rongeur, back-action
chisel, Oshsenbein chisel)
osteoplasty: rotary (carbide round bur,
diamond bur)
(B) Resective Osseous Surgery
(B) Resective Osseous Surgery
Osseous resection techniques
*sequences:
vertical grooving
radicular blending
flattening interproximal bone
gradualizing marginal bone
(B) Resective Osseous Surgery
(B) Resective Osseous Surgery
Osseous resection techniques
*vertical grooving:
1.to reduce the thickness of the
alveolar housing
2.to provide relative prominence to the
radicular aspects of the teeth
3.to provide continuity from the
interproximal surface onto the
radicular surface
(B) Resective Osseous Surgery
Osseous resection techniques
*vertical grooving:
4.rotary instruments (carbide, diamond)
5.contra-indication: close roots or thin
alveolar housing
(B) Resective Osseous Surgery
(B) Resective Osseous Surgery
Osseous resection techniques
*radicular blending:
1.extension of vertical grooving
2.to provide a smooth, blended surface for
good flap adaptation
3.contra-indications: when vertical grooving
is minor or the radicular bone is thin or
fenestrated
(B) Resective Osseous Surgery
Osseous resection techniques
*radicular blending:
4.grooving+blending
osteoplasty
it’s enough for shallow crater, thick
osseous ledge of bone on the radicular
surface and Class I & early Class II
furcation involvement
(B) Resective Osseous Surgery
(B) Resective Osseous Surgery
Osseous resection techniques
*flattening interproximal bone:
1.ostectomy:hand instruments
2.indications:
1-walled interproximal defect (hemiseptal defect)
1-wall-edged 3-wall defect
3.contra-indications:
advanced hemiseptal defect (
osseous architecture)
compromised
(B) Resective Osseous Surgery
(B) Resective Osseous Surgery
(B) Resective Osseous Surgery
Osseous resection techniques
*gradualizing marginal bone:
1.ostectomy: hand instruments
2.to remove “widow’s peak”
(B) Resective Osseous Surgery
(B) Resective Osseous Surgery
(B) Resective Osseous Surgery
(B) Resective Osseous Surgery
Flap placement and closure
1.flap replaced to the original position:
greater post-op pocket depth followed by
selective recession
2.flap apically positioned:
alter the width of the gingiva, more post-op
resorption of bone and patient’s discomfort
(B) Resective Osseous Surgery
Flap placement and closure
3.flap just cover the new bone margin:
minimize the post-op complications and
optimal post-op pocket depth
4.suturing with minimal tension
(B) Resective Osseous Surgery
Post-operative maintenance
1.non-resorbable sutures (silk) removed 1
week after op; resorbable sutures can
maintain 1-3 weeks or more
2.week1: remove sutures without
contamination and OHI
week2-3:professional prophylaxis
performed every 2 weeks
(B) Resective Osseous Surgery
Post-operative maintenance
3.healing:
soft tissue takes 2-3 weeks, bone
maturating and remodeling to 6 months
4.restorations:
at least 6 weeks
(B) Resective Osseous Surgery
Specific osseous re-shaping situations
*inter-proximal crater
*next to edentulous region
*exostoses
*furcation
(B) Resective Osseous Surgery
Specific osseous re-shaping situations
*inter-proximal crater
(B) Resective Osseous Surgery
Specific osseous re-shaping situations
*inter-proximal crater
(B) Resective Osseous Surgery
Specific osseous re-shaping situations
*next to edentulous region
(B) Resective Osseous Surgery
Specific osseous re-shaping situations
*exostoses
(B) Resective Osseous Surgery
Specific osseous re-shaping situations
*furcation: mean root trunk
(max: 4mm; man:3mm)
(B) Resective Osseous Surgery
Summary
*advantages:
1.predictable amount of pocket reduction
(enhance oral hygiene and periodic maintenance)
2.preserve the width of attached tissue
3.recontour bony abnormalities
4.proper assessment for restorative procedures
(crown-lengthening), restorative overhangs and
tooth abnormalities (enamel projection, perforation,
fractures)
thanks for your attention