Resective osseous surgery:
Intro to osseous surgery : Osseous surgery procedure by which changes in the alveolar bone can be accomplished to get rid of its deformities induced by periodontal disease or other factors. ( such as exostosis)
- Can be ADDITIVE OR SUBTRACTIVE
- Additive osseous surgery:
Procedure directed at restoring alveolar bone to its original level. - i.e.,Regeneration
- Subtractive osseous surgery: (RESECTIVE)
Designed to restore the form of preexisting alveolar bone to the level present at the time of surgery or slightly apical to it.
It is an alternative treatment method when regeneration is not feasible.
Rationale of resective surgery
Most predictable pocket reduction technique.
But performed at the expense of bone and attachment level
Rationale is based on the tenet that discrepancies in level and shapes of the bone and gingiva predispose patients to the recurrence of pocket depth postsurgically.
The goal of osseous resective therapy is to reshape the marginal bone to resemble that of the alveolar process undamaged by periodontal disease.
This procedure is combined with apically repositioned flap.
Normal architecture:
- interproximal bone is more coronal in position.
- form of the interdental bone is a function of the tooth form and the embrasure width.
-position of the bony margin mimics the contours of the cementoenamel junction.
The molar teeth have less scalloping and a flatter profile than bicuspids and incisors.
Positive, Negative, Flat Architecture
The architecture is “ positive ” if the radicular bone is apical to the interdental
The bone has “ negative ” architecture if the interdental bone is more apical than the radicular bone.
" Flat ” architecture is the reduction of the interdental bone to the same height as the radicular bone.
The ideal form of the marginal bone has similar interdental height, with gradual, curved slopes between interdental peaks.
Terminologies:
Osteoplasty refers to reshaping the bone without removing tooth supporting bone.
Ostectomy, or osteoectomy includes the removal of tooth supporting bone.
Definitive osseous reshaping implies that further osseous reshaping would not improve the overall result.
Compromise osseous reshaping indicates a bone pattern that cannot be improved without significant osseous removal that would be detrimental to the overall result.
FACTORS in selecting case:
- best applied to patients with early to moderate bone loss (2 to 3 mm) with moderate length root trunks that have bony defects with one or two walls.
- advanced attachment loss and deep intra bony defects are not candidates for resection to produce a positive contour.
- two walled defects (craters) are the most common bony defects found in patients with periodontitis.
Osseous Resection Technique and Instrumentation:
Instrumentation :
Rotary instruments - Carbide round burs, diamond burs
Hand instruments - Interproximal files (Schluger and Sugarman), Rongeurs, Back action chisels, Ochsenbien chisels.
Piezoelectric surgery
SEQUENTIAL STEPS
1. Vertical grooving
2. Radicular blending
3. Flattening interproximal bone
4. Gradualizing marginal bone
Not all steps are necessary in every case, but the sequencing of the steps in the order given is necessary to expedite the reshaping procedure, as well as to minimize the unnecessary removal of bone.
Vertical Grooving:
- Designed to reduce the thickness of alveolar housing
Performed with rotary
- Advantages – used where maximum osteoplasty is needed, useful in thick bony margins
- Contraindicated – in thin alveolar housing
Radicular Blending:
Continuation of vertical grooving
- Attempts to gradualize bone over entire radicular surface
- Provides blended smooth surface for flap adaptation
- Not necessary If VG is minimum, or radicular bone is thin.
- Both VG and RB are pure osteoplastic technique – does not reduce bulk of bone.
Classical indications of VERTICAL GROOVING and RADICULAR BLENDING
Shallow crater
Thick ledges
Class I and early class II furcation involvements
Flattening interproximal bone:
Removal of small amounts of supporting bone
Indicated in coronally placed one walled defects
Contraindicated large hemiseptal defects in such cases compromise osseous surgery is the solution
Gradualizing marginal bone:
Final – ostectomy – step
Provides base for gingiva to follow
Failure to remove widow’s peaks - allows the tissue to rise to a higher level
than the base of the bone loss in the interdental area
Hand instruments preferable – to prevent over reduction
Post-operative maintenance:
If Silk suture - 1 week or Resorbable suture - 2 to 3 weeks
Periodontal pack removed and inspected
Chlorhexidine helps in maintenance
Healing 14 21 days
Remodelling and maturation 6 months
Any Restoration after 6 weeks
Specific Situations:
CRATERS
Different techniques for the management of interproximal craters with consideration that least bone removal is done
ONE-WALLED DEFECT
Defect reduced by “ramping”angular bone.
Conclusion:
Advantages of this surgical modality
include a predictable amount of pocket reduction that can enhance oral hygiene and periodic maintenance.
It also preserves the width of the attached tissue while removing granulomatous tissue and providing access for debridement of the radicular surfaces.
In addition, the osseous resection technique permits recontouring of bony abnormalities, including hemiseptal defects, tori, and ledges.
Substantial benefits include
proper assessment for restorative procedures (e.g., crown lengthening) and assessment of restorative overhangs and tooth abnormalities (e.g., enamel projections, enamel pearls, perforations, fractures).