Platelet-derived growth factor enhancement of a mineral-collagen bone substitute

BACKGROUND: Anorganic bovine bone-collagen matrix is commercially available for bone regeneration procedures. Platelet-derived growth factor-BB (PDGF-BB) has been demonstrated to stimulate bone formation in vivo and in vitro. It was the aim of these studies to examine 1) the interaction of this mineral-collagen matrix with PDGF-BB and 2) determine if the adsorption of PDGF-BB to the mineral-collagen matrix stimulates osteoblastic cell proliferation above that of the untreated matrix. METHODS: Measurement of PDGF-BB adsorption and release was accomplished using 125I radiolabeled growth factor. The PDGF-BB was incubated with the anorganic bovine bone-collagen matrix and the amount which adsorbed was determined. In the release studies, radiolabeled PDGF-BB was adsorbed to the matrix material, then the samples were incubated in buffer for various time periods. The amount of PDGF-BB retained on the matrix was measured and the percent of growth factor released calculated. The biological activity was tested in an in vitro assay with primary culture neonatal rat osteoblastic cells. Osteoblastic cells were cultured on bone mineral-collagen matrix with known amounts of adsorbed PDGF-BB. Proliferation of the cells was assessed by 3H-thymidine incorporation and cell attachment measured by prelabeling cells with 3H-leucine. RESULTS: PDGF-BB adsorbed to the mineralized-collagen matrix material in a rapid, concentration-dependent fashion. The growth factor was slowly released from the matrix such that approximately 30% of the adsorbed protein was liberated over 10 days. PDGF-BB treated mineralized-collagen matrix displayed significantly (P < 0.05, ANOVA) enhanced proliferation of cultured osteoblastic cells compared to the mineralized-collagen matrix alone. CONCLUSIONS: These results suggest that PDGF-BB is rapidly adsorbed then slowly released from the anorganic bovine bone-collagen matrix. PDGF-BB adsorbed to this material is able to stimulate proliferation of the attached osteoblastic cells. These data suggest that it may be clinically feasible to adsorb PDGF to this bone-collagen matrix and that this combination of bone growth factor and mineral-collagen matrix has the potential for clinical applications.     

Reduction of Streptococcus mutans by probiotic milk: a multicenter randomized controlled trial

Clinical Oral Investigations - To investigate the effects of probiotics, Lactobacillus paracasei SD1, on the quantities of Streptococcus mutans in saliva and plaque samples of preschool children....     

FGF-2 stimulates periodontal regeneration: results of a multi-center randomized clinical trial

The efficacy of the local application of recombinant human fibroblast growth factor-2 (FGF-2) in periodontal regeneration has been investigated. In this study, a randomized, double-blind, placebo-controlled clinical trial was conducted in 253 adult patients with periodontitis. Modified Widman periodontal surgery was performed, during which 200 μL of the investigational formulation containing 0% (vehicle alone), 0.2%, 0.3%, or 0.4% FGF-2 was administered to 2- or 3-walled vertical bone defects. Each dose of FGF-2 showed significant superiority over vehicle alone (p < 0.01) for the percentage of bone fill at 36 wks after administration, and the percentage peaked in the 0.3% FGF-2 group. No significant differences among groups were observed in clinical attachment regained, scoring approximately 2 mm. No clinical safety problems, including an abnormal increase in alveolar bone or ankylosis, were identified. These results strongly suggest that topical application of FGF-2 can be efficacious in the regeneration of human periodontal tissue that has been destroyed by periodontitis.     

Maxillary sinus grafting with Bio-Oss or Straumann Bone Ceramic: histomorphometric results from a randomized controlled multicenter clinical trial

Introduction: This investigation was designed to compare the histomorphometric results from sinus floor augmentation with anorganic bovine bone (ABB) and a new biphasic calcium phosphate, Straumann^® Bone Ceramic (BCP). Materials and methods: Forty‐eight maxillary sinuses were treated in 37 patients. Residual bone width was ≥6 mm and height was ≥3 mm and <8 mm. Lateral sinus augmentation was used, with grafting using either ABB (control group; 23 sinuses) or BCP (test group; 25 sinuses); sites were randomly assigned to the control or test groups. After 180–240 days of healing, implant sites were created and biopsies taken for histological and histomorphometric analyses. The parameters assessed were (1) area fraction of new bone, soft tissue, and graft substitute material in the grafted region; (2) area fraction of bone and soft tissue components in the residual alveolar ridge compartment; and (3) the percentage of surface contact between the graft substitute material and new bone. Results: Measurable biopsies were available from 56% of the test and 81.8% of the control sites. Histology showed close contact between new bone and graft particles for both groups, with no significant differences in the amount of mineralized bone (21.6±10.0% for BCP vs. 19.8±7.9% for ABB; P=0.53) in the biopsy treatment compartment of test and control site. The bone‐to‐graft contact was found to be significantly greater for ABB (48.2±12.9% vs. 34.0±14.0% for BCP). Significantly less remaining percentage of graft substitute material was found in the BCP group (26.6±5.2% vs. 37.7±8.5% for ABB; P=0.001), with more soft tissue components (46.4±7.7% vs. 40.4±7.3% for ABB; P=0.07). However, the amount of soft tissue components for both groups was found not to be greater than in the residual alveolar ridge. Discussion: Both ABB and BCP produced similar amounts of newly formed bone, with similar histologic appearance, indicating that both materials are suitable for sinus augmentation for the placement of dental implants. The potential clinical relevance of more soft tissue components and different resorption characteristics of BCP requires further investigation.     

Effect of denture adhesives on oral moisture: A multicenter randomized controlled trial

PurposeThe purpose of this study was to investigate the effect of denture adhesives on oral moisture in a 10-center parallel randomized clinical trial.MethodsTwo hundred edentulous subjects wearing complete dentures were allocated into three groups: cream-type adhesive, powder-type adhesive and control groups. The adhesives (and saline solution in the control group) were applied to the mucosal surface of the dentures for 4 days, and baseline data and data after the intervention for eight meals over 4 days were obtained. For the main outcome, oral moisture was measured with a moisture checking device. Secondary outcomes were denture satisfaction, masticatory performance, denture retention, and occlusal force. In addition to between-group and within-group comparisons of oral moisture, investigations for secondary outcomes were undertaken in subgroups classified according to the degree of oral moisture at baseline (normal subgroup and dry mouth subgroup). Intention-to-treat analysis was also performed.ResultsBetween-group and within-group comparisons of oral moisture showed no significant differences. The cream-type and powder-type denture adhesives were significantly effective in the dry mouth group for denture satisfaction ratings of ability to masticate, stability, retention, and comfort of mandibular dentures (p < 0.05). The masticatory performance and retentive force of the dry mouth denture adhesive using groups were significantly improved after intervention (p < 0.05).ConclusionsThe oral moisture of complete denture wearers was not influenced by the use of denture adhesives. Our findings showed that denture adhesives improved subjective denture satisfaction, masticatory performance, and retention for complete denture patients with oral dryness.     

Radiographic outcomes of lateral sinus floor elevation with and without bone window repositioning: one-year results of a randomized controlled trial

The objective of this study was to perform a comparative evaluation of the radiographic outcomes of lateral sinus floor elevation with and without bone window repositioning (BLSFE and LSFE, respectively) when applied concomitantly with implant placement. A randomized controlled clinical trial was conducted between February 1, 2016 and May 1, 2017 including 26 individuals with at least one missing tooth. Participants were randomized 1:1 to undergo BLSFE (10 participants, 16 implants) or LSFE (13 participants, 19 implants). Bovine-derived xenograft was used in both groups and the implants were inserted concomitantly. In the BLSFE group, the antrostomy was covered with a repositioned bone window and then with a concentrated growth factors (CGF) membrane. In the LSFE group, the antrostomy was covered with a CGF membrane. Panoramic radiographs were taken before surgery (T0), immediately postoperative (T1), and at 12 months postoperative (6 months after loading) (T2). Marginal bone loss (MBL), apical bone gain, augmented alveolar bone height, and intra-sinus bone augmentation were evaluated on panoramic radiographs at T2. A linear regression analysis with generalized estimating equation models was performed. The implant survival rate was 100% at 1 year after implant surgery. The residual alveolar bone height at T0 was comparable in the BLSFE and LSFE groups (3.58 ± 1.49 mm vs 4.12 ± 1.61, P = 0.32), as was the alveolar bone height at T1 (13.61 ± 1.82 mm vs 12.38 ± 1.82 mm, P = 0.06). At T2_, significantly higher alveolar bone height, intra-sinus bone augmentation, and apical bone gain, and lower distal MBL were observed in the BLSFE group when compared to the LSFE group, with adjusting for covariates (β = 2.44, 95% CI 1.42–3.46, P < 0.0001; β = 2.38, 95% CI 1.35–3.41, P < 0.0001; β = 2.33, 95% CI 1.23–3.42, P < 0.0001; and β = ?0.43, 95% CI ?0.83 to ?0.02, P = 0.038, respectively). No significant difference was observed for mesial MBL or apical bone resorption at T2. Lateral sinus floor elevation with bone window repositioning may result in higher bone augmentation after 1 year than the traditional approach. Further research is needed to elucidate the effect of lateral sinus floor elevation with bone window repositioning.     

Treatment of deep and shallow intrabony defects A multicenter randomized controlled clinical trial

Abstract. This prospective multicenter intra-individual randomized controlled clinical trial was designed to compare the efficacy of guided tissue regeneration (GTR) with bioresorbable barrier membranes versus access flap surgery, in intra-bony defects. 2 similar defects were selected in each of 23 patients and randomly assigned to 1 of the 2 treatments. Surgery consisted of an identical procedure except for the omission of the barrier membrane in the flap control sites. At 1-year. probing pocket depth reductions were 4.3±2.3 mm in GTR treated sites and 3.0±1.5 mm in the flap control sites (p=0.02. paired t-test). Clinical attachment level (CAL) gains were 3.0± 1.7 mm in the GTR sites and 1.6±1.8 mm in the control sites (p=0.009. paired t-test). A subset analysis, performed according to the initial depth of the intrabony component of the defects (INFRA), indicated that in shallow defects (INFRA ≤3 mm) treated with the access flap alone. CAL gains were 1± 1.5 mm. while in deep ones (INFRA ≥4 mm) they were consistently greater (1.9±1.9 mm). The % CAL gains, calculated as the % of the baseline intrabony component depth, however, were almost identical in the 2 subpopulations (45.8±64.7% in shallow and 43.8±37.6% in deep defects). Similarly, in the GTR sites, linear CAL gains were greater in deep (3.7±1.7 mm) than in shallow defects (2.2±1.3 mm), but no differences were observed in terms of % CAL gains (76.1±27.7% and 75.8±45%. respectively). The frequency distribution of CAL changes expressed as %s of the baseline INFRA indicates that most of the sites treated with GTR (73% in shallow and 92% in deep defects) gained 50% or more CAL. Furthermore, many defects (64% of shallow and 33% of deep defects) reached 100% of CAL gain. The present study demonstrated that: (i) GTR with bioresorbable barrier membranes resulted m a significant added benefit in comparison with access flap alone; (ii) the linear amounts of CAL gains were greater in deep than in shallow defects; (iii) CAL gains expressed as %s of the baseine depths of the intrabony component, were similar in shallow and deep defects; (iii) the regenerative procedure tested in the present study resulted in CAL gains equal to the depth of the intrabony component of the defect in some, but not in most of the instances.     

Comparative evaluation of demineralized freeze-dried bone allograft with and without concentrated growth factor membrane in the treatment of periodontal intrabony defects: a randomized controlled clinical trial

Background

The current study’s aim was to evaluate and compare demineralized freeze-dried bone allograft (DFDBA) with and without concentrated growth factor (CGF) membrane in the treatment of periodontal intrabony defects on both a clinical and radiographic level.

Methods

30 stage III grade B periodontitis patients with bilateral intrabony defects were involved in the split mouth randomized controlled trial, and they received either DFDBA alone (control group) or DFDBA plus CGF membrane treatment (test group). At baseline and 6 and 12 months, the gingival index (GI), plaque index (PI), probing pocket depth (PPD), clinical attachment level (CAL), and gingival recession (GR) were assessed, whereas cone beam computed tomography was used to assess the bone defect height (BDH), vertical bone loss (VBL), bone defect depth (BDD), mesio-distal bone defect width (MDBDW), bucco-lingual bone defect width (BLBDW), and bone defect volume (CBCT) at baseline and 12 months.

Results

The radiographic measures BDH, BDD, MDBDW, BLBDW, and BDV in the test group likewise showed a higher reduction in PPD and gain in CAL than the control group. The results of the intergroup comparison showed that the test group had statistically significant differences in BDH, BDD, and MDBDW.

Conclusion

The data show that the test group achieved better results, with greater reductions in PPD, gains in CAL, and decreases in BDH, BDD, MDBDW, BLBDW, and BDV.

Clinical relevance

The use of concentrated growth factor in conjunction with demineralized freeze-dried bone allograft may be suggested for the treatment of periodontal intrabony defects.

     

Implant overdentures and nutrition: a randomized controlled trial

We conducted a randomized clinical trial to determine whether providing simple mandibular implant overdentures (IODs) to elderly individuals would give them a significantly better nutritional profile than those who receive complete dentures (CDs). Two hundred fifty-five edentate patients > 65 yrs were randomly assigned to receive maxillary CDs and mandibular IODs (n = 128) or CDs (n = 127). Six-month and one-year post-treatment outcomes were blood plasma levels of homocysteine (tHcy), vitamin B12, vitamin B6, albumin, serum folate, and C-reactive protein concentrations, as well as dietary intake. The association between treatment and tHcy levels was not statistically significant. A decline of folate from baseline values in both study groups, as well as those of vitamins B6 and B12 and albumin, was observed. Significant between-group differences were detected in food preparation and in the individuals' ability to chew a variety of foods. This study suggests that implant overdentures do not have a more positive effect on the nutritional state of elderly edentate individuals at 6 and 12 mos post-treatment than new complete dentures. However, those wearing IODs are significantly more likely to take in their nutrients through fresh, whole fruits and vegetables.     

Immediate nonocclusal versus early loading of dental implants in partially edentulous patients: 1-year results from a multicenter, randomized controlled clinical trial

PURPOSE: To compare the efficacy of immediate nonocclusal loading (test group) versus early loading (control group) in partially edentulous patients. MATERIALS AND METHODS: Fifty-two patients in 5 Italian private practices were randomized to 1 of the treatments: 25 to the immediately loaded group and 27 to the early loaded group. To be immediately loaded, single implants had to be inserted with a torque of > 30 Ncm, and splinted implants had to be inserted with a torque of > 20 Ncm. Implants in the immediately loaded group were provided with full acrylic resin nonoccluding temporary restorations within 48 hours after placement. After 2 months, full occluding provisional restorations were provided. Implants in the early loading group were not submerged and were loaded after 2 months. At 8 months, provisional restorations were replaced with definitive metal-ceramic prostheses. Outcome measures were prosthesis and implant failures as well as biologic and prosthetic complications recorded by nonblinded assessors. The Fisher exact test was used to compare the proportion of implant failures. RESULTS: Fifty-two implants were placed in the immediately loaded group and 52 in the early loaded group. No dropouts or complications occurred up to 14 months postinsertion. One single implant failed in the immediately loaded group 2 months after placement. There was no statistically difference for the tested outcome measures between the 2 procedures (P > .99). CONCLUSIONS: The results of this randomized controlled clinical trial with 25 patients rehabilitated with immediately restored nonocclusally loaded implant-supported prostheses compared to 27 patients restored 2 months following placement suggest that there are no major clinical differences in implant survival between these 2 protocols. No biologic or prosthetic complications occurred.     

Comparison of interdental cleaning methods: a randomized controlled trial

BACKGROUND: Although interdental cleaning is an integral component of home plaque control for periodontally involved patients, limited data exist on the periodontal benefits of commonly used interdental cleaning methods before definitive root surface debridement is undertaken. Therefore, the aim of this study was to compare the effects of a customized interdental brushing technique and a customized flossing technique on clinical periodontal outcomes prior to root surface debridement in chronic periodontitis cases. METHODS: This was a single-blind, randomized controlled clinical trial. Seventy-seven patients with chronic periodontitis were measured for plaque, relative interdental papillae level, Eastman interdental bleeding index, probing depths, and bleeding on probing at interdental sites and underwent a 10-minute hand scaling to remove easily accessible calculus deposits. Before group allocation, patients were advised on toothbrushing and instructed in two customized methods of interdental cleaning involving dental floss and precurved interdental brushes. Materials were supplied after random allocation. Participants were recalled at 6 and 12 weeks for clinical measurements, reinforcement of instructions, and fresh materials. RESULTS: There were significant reductions from baseline for all indices in both groups (P <0.01). At 6 weeks, the interdental brush group improved more than the floss group in every parameter (P <0.05). By 12 weeks, the changes in plaque, papillae level, and probing depths were significantly greater in the interdental brush group than the floss group (P <0.01). CONCLUSION: This trial demonstrated that patients were able to improve clinical periodontal outcomes by interdental cleaning, particularly with interdental brushes, even before thorough root surface debridement was undertaken.