Release of Osteogenic Markers in Immediately and Non-loaded Dental Implants
Condition: Jaw, Edentulous
MeSH terms: Jaw, Edentulous
Study type: Interventional

Summary: 
      The aim of this study was to compare the release of the osteoprotegerin (OPG), transforming
      growth factors (TGF-α), osteocalcin (OCN), osteopontin (OPN), and parathyroid hormone (PTH)
      during osseointegration of dental implants with and without immediate loading. Forty patients
      were selected and randomly divided into: Group IM - implant and prosthesis placement within
      72 hours; and Group NL - implant insertion and no prosthesis placement during 120 days.
      Peri-implant crevicular fluid (PICF) was collected immediately after implant insertion and
      with 7, 15, 30, 60, 90, and 120 days after surgery and were evaluated levels of OPG, TGF-α,
      OCN, OPN and PTH using Luminex assay. Clinical aspects (Sulcus bleeding and peri-implant
      probing depth) were also assessed. The data were compared using the ANOVA/Tukey and
      Friedman/Mann-Whitney tests (α=5%).
    

Detailed description: 
      This was a prospective, parallel and controlled clinical-laboratory trial. The population
      evaluated in this study was selected at the Graduate Clinic in Dental Implantology - UNIP-SP.

      The selected patients were randomly allocated (by a computer generated list) into:

      Group IM - (n = 20) - patients who received placement of implants and prosthesis within a
      period of 3 days, characterizing immediate loading implants protocol; Group NL - (n = 20) -
      patients who received single-stage dental implants with no placement of dental prostheses
      within a period of 4 months, characterizing non-loading implants;

      The surgeries, as well as all postoperative follow-up, were performed at the dental clinic of
      UNIP-SP. Surgical areas were anesthetized (2% mepivacaine with 1:100,000 epinephrine) and
      mucoperiosteal incisions in the alveolar ridge mucosa were made. The surgical sequence follow
      the protocol described by the implant company supplier of implants (SIN - São Paulo, SP, BR).
      In all cases, for maxilla rehabilitation, 6 implants were installed, while, for mandible, 5
      were used. Soft-tissue was sutured with simple interrupted sutures using absorbable
      polygalactin 910 suture. Postoperative care were: amoxicillin 500 mg (8-8 hours/7 days);
      sodic dipyrone 500mg (6-6 hours/3 days); 0.12% Chlorhexidine mouthwash (12-12 hours/10 days).

      The patients in the IM Group received Brånemark full arch prosthesis within 3 days after the
      implant. All prosthesis used straight mini-abutments (SIN, São Paulo, SP) and received
      occlusal adjustment and a monthly clinical monitoring (including modified bleeding on probing
      and peri-implant probing depth).

      Evaluation of osteogenic markers The collection of peri-implant crevicular fluid (PICF) was
      performed immediately after implant insertion (Baseline) and after 7, 15, 30, 60, 90 and 120
      days. The site to be collected was dried and isolated with sterile gauze. PICF was collected
      at four sites per implant using absorbent paper strips (Periopaper, Oralflow, Smithtown, New
      York). The volume of fluid was measured immediately with the aid of Periotron (Oraflow,
      Smithtown, New York) and conditioned at 400uL of PBS buffer + 0.05% Tween and then frozen at
      -80°C.

      The levels of the peri-implant osteogenic markers (OPG, OCN, OPN, TGF-α, and PTH) were
      determined using the LUMINEX/Magpix system (HBN1A-51K and HCCBP1MAG-58K, Millipore
      Corporation, Billerica, MA, USA). The samples were analyzed individually and the levels were
      estimated using a 5-parameter polynomial curve in the Xponent® software (Millipore
      Corporation, Billerica, MA). The concentration values were expressed in pg/ml.

      Statistical Analysis The null hypothesis considered in the study was the absence of
      difference in the peri-implant osteogenic markers concentration between the different loading
      protocols. For data analysis, the statistical program was used (SAS release 9.1, 2003, SAS
      Institute Inc., Cary, NC, USA). The demographic and clinical data were compared between the
      groups using Student's t-test (age), and Fisher's Exact test (gender and site of implants).
      The data on the levels of osteogenic markers were first analyzed for homogeneity using the
      Shapiro-Wilk test, which indicated non-normal distribution. Thus, the nonparametric tests -
      Friedman for intragroup and Mann-Whitney for intergroup analysis, were performed. All the
      analysis considered α=5%.
    

Intervention name(s): Osteogenic markers Evaluation; Clinical parameters evaluation; Implant instalation; Prosthesis installation; Suture; Post-operative care
Intervention type(s): Procedure; Procedure; Procedure; Procedure; Procedure; Drug
Intervention description(s): The collection of peri-implant crevicular fluid (PICF) was performed immediately after implant insertion (Baseline) and after 7, 15, 30, 60, 90 and 120 days. The site to be collected was dried and isolated with sterile gauze. PICF was collected at four sites per implant using absorbent paper strips (Periopaper, Oralflow, Smithtown, New York). The volume of fluid was measured immediately with the aid of Periotron (Oraflow, Smithtown, New York) and conditioned at 400uL of PBS buffer + 0.05% Tween and then frozen at -80°C.
The levels of the peri-implant osteogenic markers (OPG, OCN, OPN, TGF-α, and PTH) were determined using the LUMINEX/Magpix system (HBN1A-51K and HCCBP1MAG-58K, Millipore Corporation, Billerica, MA, USA).; The following parameters were assessed:
Peri-implant sulcus depth (PISD): distance from the margin of the peri-implant mucosa to the bottom of the peri-implant sulcus;
Modified Bleeding on Probing Index: the presence or absence of bleeding after 10 seconds on probing around implants.; The surgeries, as well as all postoperative follow-up, were performed at the dental clinic of UNIP-SP. Surgical areas were anesthetized (2% mepivacaine with 1:100,000 epinephrine) and mucoperiosteal incisions in the alveolar ridge mucosa were made. The surgical sequence follow the protocol described by the implant company supplier of implants (SIN - São Paulo, SP, BR). In all cases, for maxilla rehabilitation, 6 implants were installed, while, for mandible, 5 were used.; The patients in the IM Group received Brånemark protocol prosthesis within 3 days after the implant. The implants were first molded and the models sent for prosthesis confection (LABDENTAL, São Paulo, SP, Brazil). All prosthesis used straight mini-abutments (SIN, São Paulo, SP), that ranged from 1mm to 4mm in height, whose were tightened with 20N of torque, followed by occlusal adjustment and clinical monitoring; Soft tissues sutures were done using absorbable polygalactin 910 suture.; Postoperative care were: amoxicillin 500 mg (8-8 hours/7 days); sodic dipyrone 500mg (6-6 hours/3 days); 0.12% Chlorhexidine mouthwash"
Other intervention name(s): Osteoprotegerin; Osteopontin; Osteocalcin; PTH; TGF-alpha; Peri-implant probing depth; Bleeding index; Dental implants; Jaws rehabilitation; Brånemark protocol; Full arch rehabilitation; Implant supported prosthesis
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Screening
Keywords: Dental Implants; Osseointegration; Immediate Dental Implant Loading; Bone formation