Comparison of the GTR Procedure Alone and in Combination With Immediate OTM

Study Overview
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Brief Summary
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The aim is to evaluate in a prospective, randomized, controlled clinical study the healing of a GTR procedure, when it is combined with an immediate orthodontic tooth movement or used alone. Clinical, radiological and reentry (histological) evaluation of a regenerative surgical method (GTR + grafting material) with different postsurgical healing patterns in the treatment of wide, non-containing intrabony defects.

Detailed Description
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There is limited histological data in literature on the behavior of xenogeneic graft materials in intrabony defects used in periodontal regenerative therapy followed by orthodontic tooth movement (OTM). This clinical study aims to clinically and histologically evaluate the healing response of the periodontal tissues and the healing pattern of a non-resorbable graft material, when they are exposed to orthodontic forces. Therefore teeth presenting non-contained intrabony defects in combination with pathologic tooth migration (PTM) are included in this prospective clinical study. Guided tissue regeneration (GTR) with the application of deproteinized bovine bone mineral (DBBM) and a resorbable collagen membrane is utilized to surgically treat the periodontal defects, which is followed by a random allocation of the patients into test or control group. Subject teeth undergo an early initiated orthodontic treatment after surgery or stay splinted without any tooth movement in the latter groups, respectively. Teeth in test group can be further divided into subgroups, depending if they are moved toward to the former defect (pressure site) or moved away from the defect (tension site). After 9 months of healing a reentry surgery is performed, when a biopsy core is removed with a microtrephine from the previous defect site. The sample is evaluated by means of histology supplemented with histomorphometry, which is the primary outcome variable. Periodontal clinical parameters measured at baseline and at 9 months serves for secondary outcomes. Several studies confirmed the success of graft materials in such comprehensive treatment approaches clinically, but we lack the human histologically proved data, whether DBBM bone substitute can be used safely when the tooth is exposed to OTM. Our main question is how orthodontic induced bone remodelling interferes with these graft particles, can they heal the same or even better compared to control sites. Tissue response might be different also in the case of the two test subgroups.

Official Title
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Comparison of the Guided Tissue Regeneration (GTR) Procedure Alone and in Combination With Immediate Orthodontic Tooth Movement (OTM) in the Treatment of Non-containing and Wide Intrabony Periodontal Defects: a Prospective RCT

Conditions
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Intrabony Periodontal Defect

Intervention / Treatment
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* Procedure: Guided tissue regeneration (GTR)
* Device: Orthodontic tooth movement (OTM)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Periodontitis with intrabony defect (Intrabony component ≥ 4mm, defect radiological angulation > 25°, 1 or max. 2 bony walls (no buccal bony wall), non-containing defect), no class III. furcation involved teeth Selected tooth must be in a traumatic occlusion or not in a gnathologically correct bite (migrated, elongated, tilted tooth, etc.). Patients must not be heavy smokers (<5 cigarettes/day). Full mouth plaque and bleeding scores (FMPS and FMBS) of <20% (O'Leary et al. 1972). The patient is able to comply with the study -related procedures (i.e. good level of oral hygiene, follow-up procedures). The patient is able to fully understand the nature of the study, signed informed consent. Exclusion Criteria: Pregnant women. Participation in another clinical study within 30 days prior to study start. Alcoholism, drug dependency, heavy smoking (>5 cigarettes/day). Known infection with HIV, HBV, or HCV. Patients requiring chemo- or radiotherapy. Previous or current radiotherapy of the head. Uncontrolled or insulin-dependent diabetes mellitus Clinically relevant osteoporosis or systemic disease affecting bone metabolism Clinically relevant cardiovascular disease e.g., decompensated cardiac insufficiency, hemodynamically relevant heart valve defects, or myocardial infarction during the last three months. Clinically relevant blood coagulation disorder. Previous or current treatment with systemic corticosteroids (within 2 months prior to screening visit) of more than 5 mg/day prednisone equivalent. Previous or current therapy with bisphosphonates at least for 30 days within the last 12 months before screening visit.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Patients undergo GTR procedure, after they are randomly allocated either to test (with OTM) or control group (without OTM)
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Test group<br>Test subjects receive GTR and early initiation of OTM. | Procedure: Guided tissue regeneration (GTR)<br>* GTR is handled with the utilization of a coronally advanced flap, followed by a thorough debridement of the denudated root surface and the intrabony component. Regenerative materials are resorbable collagen membrane (BioGide, Geistlich Phara AG, Wolhusen, Switzerland) and deproteinized bovine bone mineral (BioOss, Geistlich Phara AG), finally surgery is finished with multilayer suturing technique.<br>* Other names: Regenerative surgery of an intrabony periodontal defect;Device: Orthodontic tooth movement (OTM)<br>* An early initialization of the tooth movement with the help of a multibond fixed orthodontic device utilizing low level of continuous orthodontic forces.<br>* Other names: Multibond fixed orthodontic appliance;|
| Active Comparator: Control group<br>Control subjects receive only GTR. | Procedure: Guided tissue regeneration (GTR)<br>* GTR is handled with the utilization of a coronally advanced flap, followed by a thorough debridement of the denudated root surface and the intrabony component. Regenerative materials are resorbable collagen membrane (BioGide, Geistlich Phara AG, Wolhusen, Switzerland) and deproteinized bovine bone mineral (BioOss, Geistlich Phara AG), finally surgery is finished with multilayer suturing technique.<br>* Other names: Regenerative surgery of an intrabony periodontal defect;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Amount of newly formed bone by means of histomorphometry | The percentage of newly formed bone of the former periodontal defect after a biopsy harvesting during a reentry surgery 9 months after the GTR intervention | 9 months postoperatively | 
| Amount of graft material by means of histomorphometry | The percentage of graft material (BioOss, Geistlich Pharma AG, Wolhusen) of the former periodontal defect after a biopsy harvesting during a reentry surgery 9 months after the GTR intervention | 9 months postoperatively | 
| Amount of connective tissue by means of histomorphometry | The percentage of connective tissue of the former periodontal defect after a biopsy harvesting during a reentry surgery 9 months after the GTR intervention | 9 months postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CAL | Clinical attachment level gain | 9 months postoperatively | 
| PPD | Pocket probing depth reduction | 9 months postoperatively | 
| GR | Change in gingival recession | 9 months postoperatively | 
| Bone gain | The absolute fill of the periodontal defect | 9 months postoperatively | 
| Bone loss | The change of the crestal bony wall | 9 months postoperatively | 
| Intrabony fill | The change of the intrabony component compared to the initial intrabony defect depth (in percentage) | 9 months postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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guided tissue regeneration, orthodontic tooth movement, histology, bone remodeling, deproteinized bovine bone mineral