報告者：傅超俊 報告日期： 2012/05/15

Introduction  a high incidence of discrepancies in gingival margin levels between an implant crown and the contralateral natural tooth. a lack of hard and soft tissue Gotfredsen K.2004; Henriksson H,2004

 To achieve favorable esthetic results by regenerating hard and soft tissues surgical procedures to preserve or to reconstruct hard and soft tissues ○ outcome is not always predictable. orthodontic forced eruption (OFE) or orthodontic implant site development (OISD), a technique described by Salama H and Salama M(1993).

Aim  to evaluate the soft and hard tissue response to OISD,  to evaluate the clinical indications for different degrees of periodontal attachment loss on the extruded tooth  to evaluate the implant survival rate in areas where OISD was performed

Material and Method  From March 2004 until December 2009  A total of 32 teeth in 13 patients; 27 were replaced by implants and 5 were replaced by pontics

Treatment course  Defect diagnosis  Periodontal treatment, root canal therapy, OFE,  Tooth extraction, flapless immediate implant placement with immediate provisionalization,  Tissue conditioning with new provisional prostheses for at least 6 months  Delivery of the definitive restoration

Periapical radiographs and all measurements  Before periodontal treatment (T-0) ;  2 months after periodontal treatment, at the beginning of orthodontic treatment (T-1)  During orthodontic treatment at 1-month intervals (T-n)  On the day of extraction and implant insertion (T-end)  At 6-month intervals

Periodontal treament  pocket depths 1 ~ 5 mm scaling and root planing in combination with topical antibacterial treatment (chlorhexidine0.1% rinse three times daily)  pockets >5 mm scaling and root planing in combination with topical antibacterial treatment; 1 month later : open flap debridement (modified Widman flap) in combination with topical antibacterial treatment (chlorhexidine0.2% three times daily for 2 weeks).

Orthodontic treatment  1 mm of extrusion per month Light (15 to 50 g) continuous forces 4- to 5-week rest period between activations  Buccal root torque component To increase the buccolingual bulk of alveolar bone  The goal was to exceed by at least 2 mm the bone level of the contralateral tooth  2-month period of stabilization to allow mineralization of the new trabeculae

Extaction and implant  Two days before implant placement, a final, rapid extrusive force was applied to the extruded tooth/teeth  All teeth were extracted without raising a flap  When a gap was present between the implant and the alveolar bone plate Autologous bone chips or nonresorbable bone substitute particles (Bio-Oss, Geistlich Pharma) were placed to provide a solid scaffold for blood clot formation. No flap was raised and no attempt was made to achieve primary closure with sutures

Result

Data Analysis  OE : Amount of orthodontic extrusion  BA : Amount of bone augmentation per extruded tooth  KGA : Amount of keratinized gingiva augmentation (vertical augmentation of the keratinized width)  MGJM : Movement of the MGJ  GA : Amount of gingival augmentation per extruded tooth (coronal movement of the gingival margin)  R : Amount of recession occurred during orthodontic treatment  GTA : Changes in gingival thickness on the facial side  PDR : Pocket depth reduction during orthodontic extrusion  PDT2 : pocket depth at the end of orthodontic extrusion  PDT1 : pocket depth at the beginning of orthodontic extrusion (2 months after periodontal treatment)  BA/OE % : Efficacy of the orthodontic vertical movement in creating new bone (bone augmentation/ amount of orthodontic movement ratio;)  GA/OE % : Efficacy of the orthodontic vertical movement in creating new soft tissue, (gingival augmentation/ amount of orthodontic movement ratio;)  Changes in papillae height

 The implant survival rate was 96.3% (1 of 27 implants failed). during a follow-up period ranging from 18 to 61 months,

Discussion--- Hard Tissue Changes  Bone formation/vertical movement ratio was about 70% the vertical orthodontic tooth movement did not convert completely into new bone. tooth having to erupt out of the pocket  No statistically significant differences in the amount of BA/OE in the four subgroups it is possible to regenerate bone by erupting teeth that have lost more than 90% of the surrounding bone

Soft Tissue Changes (1)  gingival growth GA/OE% was around 65% but variability was more than bone  Three different clinical scenarios Gingival migration was proportional to the orthodontic movement Gingival overgrowth was observed very little gingival growth was observed

Soft Tissue Changes (2)  Behavior of the gingival margin on adjacent teeth---”blanket effect” When pulled up from two corners, moves not only at the corners but at the center as well, albeit to a lesser extent

Soft Tissue Changes (3)  Changes in the position of the MGJ--- four possible clinical The MGJ does not move coronally but the gingival margin does The MGJ moves coronally together with the gingival margin,. Neither the MGJ nor the gingival margin move coronally,. The MGJ moves coronally, while the gingival margin does not

Soft Tissue Changes (4)  Biotype conversion  The thickness of the gingiva on the buccal side. An increase in thickness was a consistent finding

Advantages of OFE/OISD  Nonsurgical means  To rebuild both the hard and soft tissues and insert an implant without ever raising a flap  to overbuild the site to compensate for postextraction remodeling

Conclusion  Bone augmentation/orthodontic extrusion was about 70% and gingival augmentation/orthodontic extrusion was about 65%.  Residual attachment level was not a limitation to the amount of regenerated bone.  The implant survival rate was 96%.