MIST Versus M-MIST for the Treatment of Intrabony Defects

Minimally Invasive Surgical Techniques of Single Versus Double-flap for the Treatment of Isolated Intrabony Defects: a Randomized Controlled Clinical Trial

This is a 12-month longitudinal, double-blind, parallel-design randomized controlled clinical trial involving surgical therapeutic intervention (Phase 4). It will include 50 participants aged 21 diagnosed with periodontitis (Stage III/IV, Grade A or B), divided into a Test Group (n=25, Minimally invasive single-flap surgery) and a Control Group (n=25, Minimally invasive double-flap surgery). The objective of this randomized, double-blind clinical study is to compare clinical, radiographic, and patient-centered outcomes between minimally invasive single-flap and double-flap techniques in treating isolated infra-bony defects. Twenty-five patients will be treated using the single-flap approach, and 25 patients will receive the double-flap elevation technique. Clinical parameters (plaque and bleeding scores, probing depth, gingival recession, clinical attachment level, and papillary dimensions), digital measurements (changes in gingival margin and papillary volume), radiographic assessments, and patient-centered outcomes (VAS scale) will be evaluated immediately before surgery, at 6 and 12 months post-procedure, while early healing will be assessed after 1 and 2 weeks following the procedures. Mean values and standard deviations will be calculated for each variable, normal distribution will be tested using the Shapiro-Wilk test, and comparisons will be conducted using Student's t-test and one-way ANOVA. A significance level of 5% will be used for all analyses.

This is a clinical trial, a randomized controlled double-blind parallel-design study. Participants will be recruited from patients diagnosed with periodontitis (Stage III/IV, Grade A or B) based on inclusion and exclusion criteria at the Postgraduate Periodontics Clinic of the Dental College of Piracicaba in the State University of Campinas (FOP-UNICAMP). Objective #1: To compare the clinical outcomes of surgical treatment of isolated infra-bony periodontal defects using minimally invasive single-flap surgery (Cortellini & Tonetti, 2009) versus double-flap surgery (Cortellini & Tonetti, 2007). Clinical parameters, including plaque presence, bleeding on probing, probing depth, gingival recession, clinical attachment level (primary outcome), early healing index, aesthetic and tissue professional evaluation, will be assessed. Patient Selection: The sample size calculation was based on a previous study (Trombelli et al., 2012), resulting in 50 participants, with 25 in each group. Inclusion Criteria: Participants must be 21 years old, of both sexes, systemically healthy, diagnosed with periodontitis (Stage III/IV-Grade A or B), have at least one isolated infra-bony interproximal defect with probing depth of 6mm or more, plaque and bleeding indices below 20%, and provide informed consent. Exclusion Criteria: Exclusion criteria include systemic conditions contraindicating periodontal surgery, the need for prophylactic antibiotics, systemic disorders, bisphosphonate use, previous antibiotic or steroid use, illicit drug use, smoking, inadequate restorations, endodontic lesions, untreated caries, tooth mobility, pregnancy, and lactation. Exit Criteria: Participants can exit the study voluntarily or if additional procedures outside the protocol are required. Experimental Groups: Participants will be randomly assigned to two treatment groups: Control Group (double-flap minimally invasive surgery) and Test Group (single-flap minimally invasive surgery). Clinical Protocol: The clinical protocol involves pre-surgical therapy, surgical therapy, and post-operative care. Surgery will be performed using magnification (2.5x). Patients will receive post-operative analgesics and instructions for oral hygiene modifications. Periodontal maintenance will occur at specific intervals. Clinical Parameters: Clinical parameters including plaque index, bleeding on probing, probing depth, gingival recession, clinical attachment level, and early healing index will be measured at baseline, 6 months, and 12 months. Objective #2: Digital parameters, including mean change in papillary volume (mmVP) and change in gingival margin (mGM), will be assessed through intraoral scanning at baseline and 12 months. Objective #3: Radiographic measurements (linear, angular, and subtraction) will be performed before surgery and 12 months after using specialized software. Objective #4: Patient perception of pain and analgesic consumption will be evaluated using the Visual Analogue Scale (VAS) at various time points post-surgery. Dissemination and Evaluation: The results will be presented at dental/periodontal congresses and published in specialized journals. Statistical Analysis: Descriptive statistics will be used, and normality will be tested. Comparisons will be made using Student's t-test, one-way ANOVA, or non-parametric tests if data do not follow a normal distribution. A significance level of 5% will be used for all analyses.

Randomized controlled double-blind parallel-design clinical trial with a longitudinal duration of 12 months per participant, involving surgical therapeutic intervention.

This is characterized by a vestibular mucoperiosteal envelope flap without relaxing incisions. Sulcular incisions will be made on the vestibular surface of the teeth included in the surgical area, adjacent to the infraosseous defect. The mesiodistal extension of the flap will be kept to a minimum necessary to access the defect. In the papillary area over the infraosseous defect, an oblique or horizontal incision will be made at the level of the interdental papilla, following the contour of the bone crest. The vestibular flap will be elevated, leaving the lingual/palatal portion adhered, only to allow access to the bone defect. The defect will be instrumented with mini-curettes and specific ultrasonic tips, and the defect will be filled only with a blood clot after this procedure. Primary closure will be achieved with internal vertical and/or horizontal mattress sutures, which may be complemented with simple sutures, all using specific suture threads.

A vestibular envelope flap, without vertical relaxing incisions, will be raised on the vestibular and lingual/palatal sides. Primary intrasulcular incisions will be made to the alveolar crest, encompassing the teeth included in the surgical area. In the interproximal area, incisions will follow the principle of preserving the papilla (Modified Papilla Preservation Technique = MPPT or Simplified Papilla Preservation Flap = SPPF), depending on the available interproximal space (Cortellini et al., 1995, 1999). The mesiodistal extension of the flap will be minimized to provide adequate access to the defect. The defect will be instrumented using mini-curettes and specific ultrasonic tips, and the defect will be filled only with a blood clot after these procedures. Flap closure will be achieved with internal horizontal and/or vertical mattress sutures, which may be modified or complemented with simple sutures, all using specific suture threads.

Inclusion Criteria: Systemically healthy individuals Diagnosis of periodontitis (stage III/IV - grade A or B) Presence of 20 or more teeth in the oral cavity Presence of at least one isolated interproximal infra-bony defect (without extension of the defect to the lingual or palatal area - assessed with preoperative bone sounding), with a probing depth of 6 mm or more, and a radiographic infra-bony component ≥ 4 mm, not associated with bifurcation areas, in anterior or premolar teeth (Schincaglia et al., 2015) Plaque index and bleeding on probing index ≤ 20% (baseline) Individuals providing informed and voluntary consent Exclusion Criteria: Individuals who are not available for study evaluation appointments Systemic conditions that contraindicate periodontal surgery Patients requiring prophylactic antibiotics Compromised systemic condition (leukocyte dysfunction, bleeding disorders, neoplasms, uncontrolled metabolic or endocrine disorders, HIV infection) Individuals using bisphosphonates (oral or injectable use) Individuals using antibiotics and steroids (within 6 months prior to the study start) Illicit drug users Smokers Individuals with the tooth associated with the infra-bony defect having inadequate restoration, endodontic lesion, inadequate endodontic treatment, untreated carious lesions, and Grade III mobility Pregnant and lactating Women