Osseous Resective Surgery Flashcards
Do you need osseous surgery or you can apically position the flap without osseous?
Olsen: Longitudinal study comparing apically repositioned flaps w/ and w/o osseous surgery
12 patients w/ moderate periodontitis
At 5 year follow up: Resulted in fewer residual pockets and less inflammation than flap curettage (2.3x greater bleeding 4+ mm pockets), especially in 5-8mm pockets.
Is osseous better than MWF or SRP?
Kaldahl
One of the only studies that is truly statistically significant in this lit packet
Compared coronal scaling, SRP, SRP + MWF, or SRP + FO
Results:
MWF has greater PD reduction than SRP at first, but later evens out
In moderate and deep pockets, sustained CAL gain is possible for SRP, MW, and FO. Attachment gains were significantly greater for deeper sites than shallow sites.
CS is not as favorable as other treatment modalities (duh)
No stastically significant difference in outcome between FO, SRP, MWF.
What’s better SRP, Osseous, or MWF?
5 year longitudinal study of moderate to severe perio dz (16 patients)
No statistically significant difference between the three procedures
BL: Periodontal therapy, with proper OH and regular maintenance, can maintain periodontal health. SRP, OS and MW similarly effect PD reductions with slight changes in CAL after 5 years. Any treatment in a 1-3mm PD was detrimental to CAL and PD at 5 years.
What’s better fibre retention osseous resective surgery osseous surgery in treatment of Shallow infrabony defects?
Cairo:
shallow = less than 3 mm
Significantly more bone is removed in traditional osseous group ~1mm
the fibReORS group had significantly less post-operative discomfort (requiring fewer analgesics), less dentinal hypersensitivity, and greater esthetic outcomes
FibReORS compares favorable to ORS in regards to reduced post-operative PDs and less recessions. Also has greater patient satisfaction.
What is fibre retention osseous surgery?
Carnevale in 2007 proposed Fibre retention osseous surgery. It uses the CT attachment instead of the base of the osseous defect as the reference for performing osseous surgery. After flap reflection the perio probe is used to determine the location of fibers remaining on the root surface and within the infrabony defect. Then osseous surgery is limited to the most coronal portion of this CT attachment located within the infrabony defect.
What is better for the treatment of shallow intrabony defects traditional ORS or FibREOS?
Aimetti:
FibReORS has equal amounts of PD reduction with less CAL loss
Good option in 3 mm or less defects
What is the ultimate goal of osseous resective surgery? Explain how we get there
Schluger
Stated that Pocket elimination is a goal of surgery,
soft tissue form and depth ultimately depend on hard tissue, physiologic osseous contours must be attained to assist in pocket elimination
YOU MUST ADDRESS THE BONE
Isn’t osseous surgery harmful to our periodontal patients because we are removing supporting bone?
Selipsky review paper
Larato (1970) showed that ostectomy removed insignificant amounts of supporting bone height 0.6 mm on circumferential average
Greatest amount of resected is mid-buccal, mid-lingual or palatal surfaces next to interproximal defects with usually only 1 mm removed.
Buccal and lingual bone removal appears less important in terms of tooth support than interproximal bone because of their smaller surface area, especially more posteriorly.
Why should I use an apically positioned flap versus a gingivectomy?
Nabers
attached gingiva should be conserved since it is keratinized and best suited to function in areas of mastication.
alveolar mucosa cannot withstand the friction of food during mastication.
Standard gingivectomy procedure can result in marginal tissues composed of nonkeratinized alveolar mucosa, which is not desirable.
Pockets extending beyond the mucogingival junction may be treated by apically repositioning of the flap. Pockets are eliminated and attached gingiva is preserved.
Name some advantages and disadvantages of an apically positioned flap
Advantages of the apically repositioned flap:
- Rapid healing by primary intention and fewer adverse post-op sequelae
- Maximum bone coverage preventing macroscopic sequestration and minimizes alveolar crest loss
- Control of post-op amount of gingiva with thinning incision
- Retaining the mucogingival complex allows for deepening of shallow vestibules and frenum repositioning without producing a large wound
- Useful when only 1 or 2 teeth are involved, avoiding exposure of bone on healthy adjacent teeth
- Controlled surgery
Disadvantages:
1. Technically difficult: precise suturing and flap thinning necessary
- Difficult when faced with little pre-op gingiva
- Poor access in mandibular molar region with shallow vestibule (double flap (split thickness) procedure recommended)
Indications:
- Areas where the base of the pocket is near, at, or apical to the mucogingival junction
- Sufficient gingiva will remain after thinning and manipulation of the flap
look at Figure 3 in this article according to Aaron
How do you define bony defects in osseous surgery?
Ochsenbein : Bony craters may be identified according to morphology and depth:
shallow = 1-2 mm deep medium = 3-4mm deep
deep = 5 mm or more
What is the rationale for doing osseous resective surgery?
PD reduction through contouring of the bone so gingival tissue adapts to that architecture
Palatal vs lingual approach is the avoidance of the buccal furcation
Quote the Becker study on your board
Ochsenbein: Combined approach to the management of intrabony defects
I. Three-Walled Bony Defects: Prichard originally described intrabony defects as surrounded by bony walls on three sides with the tooth root forming the fourth wall. There may be combinations within the walls, but only the inside of the defect that is apical to all three bony walls is “intrabony” Previous research supports that deep three wall defects are good candidates for bone regeneration. The deeper the defect, the more bone fill. It is believed that areas of the defect that are one- or two-walled components heal with residual probing depth. In studies of three-walled defects, only 16 out of 130 were pure three-walled defects, and most of these were shallow.
II. Residual Bony Defects: Residual defects can be divided into soft tissue and hard tissue aspects. Soft tissue components are present in unmanaged one and two-walled defects and incomplete fill of the three-walled bony defect. The hard tissue aspect is represented by the unfilled one or two-walled components and the unfilled part of the three-walled bony defect. Why is there partial regeneration? Several studies have examined the effect of plaque on bone regeneration. Osseous defects in the presence of excellent plaque control had bone fill, whereas those with poor plaque control had continued presence of disease. These findings suggest that the absence or presence of plaque is the determining factor between regeneration or deterioration of bone.
III. Factors important in the management of pocket depths close to newly regenerated bone. Patient compliance with plaque control and maintenance visits, as well as treatment philosophies and professional skills of the practitioner are necessary to manage these problems long term.
IV. Therapeutic Options: Methods for regeneration of three-walled defects coupled with one and two-walled defects are discussed. The first method includes flap procedures with membranes, removing supporting bone on the tooth adjacent to the defect. Another method of managing defects is use of a two-stage surgery where a membrane is placed over an unaltered defect, allowed to heal, and a secondary surgery is performed to attempt regeneration again in the residual defects. A third option, which has received the most merit, is to manage the one and two-walled defects by osseous surgery and place a membrane in the three-walled defect to allow for better adaptation.
V. Factors affecting membrane adaptation: Eliminating the one and two-wall components to obtain a uniform base for support, buckling or distortion of the membrane before flap closure, collapse of the membrane into the defect, complete gingival coverage, thinning thick lingual and buccal bone prior to membrane placement, and root anatomy.
VI. Discussion: There is a belief that more bone fill will occur in a pure three-walled defect than one that is coupled with one and two bony walls. The most predictable three-walled bony defect is a deep lesion located distal to the terminal molar. The role of a membrane in GTR is to isolate the bony defect and to permit the periodontal ligament cells to form a new attachment by blocking the migration of epithelium into the defect.
BL: In this review of three-walled defects, the deeper three-walled defects without one or two-wall components exhibited the most bone fill. If there is a one and/or two-wall component associated with the three-wall defect, it is recommended to reduce these bony walls before placing the membrane over the three-walled defect and attempting periodontal regeneration.
Wilderman: Exposure of bone in periodontal surgery
Bone Exposure:
If bone is exposed during surgery and then covered by a flap, it is considered temporarily exposed. If bone remains exposed after surgery until healing tissue covers it, then it is considered permanently exposed.
Bone may be exposed in 3 different areas:
1) Radicular (Buccal or lingual to the root) bone, 2) Furcal bone, or 3) Interproximal bone. Bone over the root is often narrow with few, if any, marrow spaces. Interdental or furcal bone often is a dense compact vestibular plate with definite underlying spongy bone, consisting of many marrow spaces.
Permanent bone exposure: Superficial exposed cortical plate of the alveolar bone becomes necrotic. Resorption occurs by undermining resorption. Underlying bone is viable. The first phase of repair is the osteoclastic phase (2-10 d). Osteoclasts resorb necrotic bone and a superficial fibrin clot develops at the wound edges/severed PDL. In radicular areas a continued periodontal resorption results in complete loss of the exposed buccal bone and alveolar crest is lowered. Resorption in interdental and furcation areas results in loss of the vestibular and crestal compact bone, which creates a flat slope.
The greatest bone formation occurs 21-28 days after surgery. In the interdental and furcation areas there is complete restoration of bone. In the root area bone apposition never completely reconstructs the lost bone. In the radicular area, fibrous tissue of the new gingiva above the alveolar crest doubles in length and compensates for the low crestal bone level.
CT and Epithelium: By the 2nd day after surgery granulation tissue proliferates from exposed PDL, lateral wound edges, and papillae. 6 days post surgery the tissue originates from marrow spaces and PDL. 14 days post-surgically there is a union of these tissues. Epithelium completely covers CT at 21 days post surgery. The gingival CT and Epithelium completely mature within 6 months.
Temporary bone exposure: A fibrin clot develops between the replaced flap and the bone by about 2 days. New granulation tissue replaces the fibrin clot at around 4 days. From 4-8 days, bone resorption occurs on periosteal surface of the bone. At 10 days post surgery new bone formation begins. Bone formation continues for 21 days. Less net bone resorption occurs over the root if the flap is replaced versus left exposed. Complete reconstruction usually occurs in the interproximal or furcal area regardless of the technique used.
CT and Epithelium heal in a similar process as mentioned above, but organization and maturation occur faster. Complete maturation usually occurs within 3 months.
He created a lot of necrotic bone
Pfeifer: The growth of gingival tissue over denuded bone
R: The first day after surgery biopsies results showed that tissues appeared the same as day of surgery. Day 2: Immature CT proliferating from the PDL. Bone began to show signs of degeneration. Day 4: Increased CT proliferation occlusally. Osteoclasts began to appear. Day 7: Immature tissue covering bone and attached to the root. Day 21: maturation of the tissue. Attachment to the tooth surface has occurred and thus established the epithelial cuff.
BL: The origin of the new connective tissue component of the gingival tissue covering the denuded bone was primarily the PDL. Once the new tissue was put into function, it changed characteristics to that of attached gingiva. The amount of osteoclastic activity following surgery varied with the amount of bone exposed and how the bone was protected. Repair of the denuded area started on the 2nd and lasted to the 7th –10th day. Denuding of the bone resulted in minimal loss of bone.
