Ren-Yeong Huang DDS PhD 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 *subtractive *addictive

(B) Resective Osseous Surgery Selection of treatment technique 1-wall 2-wall 3-wall wide narrow shallow deep recontoured 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 (8- 12weeks) *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 ( compromised osseous architecture)

(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