Antimicrobial photodynamic therapy as an alternative to systemic antibiotics: results from a double-blind, randomized, placebo-controlled, clinical study on type 2 diabetics.

AIM: This double-blind, placebo-controlled clinical study compared multiple applications of the antimicrobial photodynamic therapy (aPDT) treatment protocol, to systemic doxycycline as adjuvant to scaling and root planing (SRP) on type 2 diabetic patients on clinical, systemic and immune-inflammatory outcomes. MATERIALS AND METHODS: Thirty patients with Hba1c >7% were allocated in two groups, SRP + Doxy (n = 15) using systemic doxycycline 100 mg/day (14 days) and SRP + aPDT (n = 15) with multiple applications (0, 3, 7 and 14 days). Primary outcome was glycated haemoglobin levels (HbA1c). Clinical parameters: plaque score (PS), bleeding on probe, probing depth, suppuration, gingival recession, and clinical attachment level, percentage of pockets with desired clinical endpoint were measured at baseline and 3 months after therapy. Cytokine profile was assessed at 0, 1 and 3 month to measure IL1-ß, TNF-α and TGF-ß on gingival crevicular fluid. RESULTS: No significant difference was detected on HbA1c, between treatments. The SRP + aPDT group showed advantage on reducing moderate pockets in single-rooted teeth at 3 months. SRP + aPDT presented better results at 3 months on IL1-ß levels. There were no significant differences between TNF-α and TGF-ß. CONCLUSIONS: Both treatments improved clinical and systemic outcomes (Hba1c). SRP + aPDT performed better in moderate probing pocket depth on single-rooted teeth, reduced favourably inflammation in short term, and may be an alternative to systemic antibiotics. (Clinicaltrials.org ID NCT01595594).

Adjunctive effect of antimicrobial photodynamic therapy to nonsurgical periodontal treatment in smokers: a randomized clinical trial.

The aim of this study was to investigate the adjunctive effect of antimicrobial photodynamic therapy (aPDT) to scaling and root planing (SRP) in smokers with chronic periodontitis. Twenty subjects had two contralateral teeth randomly assigned to receive SRP (SRP group) or SRP + a single episode of aPDT (SRP + aPDT group), with a diode laser and a phenothiazine photosensitizer. Plaque index, bleeding on probing, probing depth (PD), clinical attachment level (CAL), and gingival recession were recorded, and gingival crevicular fluid was collected for assay of IL-1ß and matrix metalloproteinase (MMP)-8 levels. There was a significant PD reduction (SRP 1.81 ± 0.52 mm/SRP + aPDT 1.58 ± 1.28 mm; p < 0.001) and a significant CAL gain (SRP 1.60 ± 0.92 mm/SRP + aPDT 1.41 ± 1.58 mm; p < 0.001) for both groups. Significant differences were not observed in between-group comparisons. IL-1ß level in gingival crevicular fluid was higher in SRP group after 1 week (SRP 24.65 ± 18.85 pg/µL/SRP + aPDT 34.07 ± 24.81 pg/µL; p = 0.048), and MMP-8 level was higher in SRP group after 12 weeks (SRP 303.31 ± 331.62 pg/µL/SRP + aPDT 534.23 ± 647.37 pg/µL; p = 0.024). There were no statistically significant differences in intragroup comparisons. The adjunctive effect of aPDT did not warrant improvements on clinical parameters in smokers. However, it resulted in a suppression of IL-1ß and MMP-8 when compared with SRP alone.

Buccal bone plate remodeling after immediate implants with or without synthetic bone grafting and flapless surgery: a histomorphometric and fluorescence study in dogs.

OBJECTIVE: The aim of this study was to evaluate the buccal bone plate remodeling after immediate implantation using the flapless approach with or without bone graft into the gap between the implant and the buccal bone. MATERIAL AND METHODS: Eight dogs had the mandibular bicuspids extracted without flaps, and four implants were installed on each side, totaling eight implants per animal. Randomly, in one side, the implants were positioned at the bone crest level (equicrestal), and on the opposite side, the implants were positioned 2 mm subcrestal. All the implants were positioned 2.0 mm from the buccal bone plate (gap) and associated or not with grafting material. Therefore, the following treatments were performed: implants subcrestal test (SCTG) with bone graft and control (SCCG) without bone graft, and equicrestal test (ECTG) with bone graft and control (ECCG) without bone graft. One week following the surgeries, metallic prostheses were installed. Bone markers were administered 1, 2, 4, and 12 weeks after implant placement for fluorescence analysis. Ground sections were prepared from 12-week healing biopsies, and histomorphometry was performed. RESULTS: The histomorphometric evaluation presents significant better results for the ECTG in the vertical crestal bone resorption, but the other parameters showed better results for the SCCG. The fluorescence evaluation in adjacent areas showed numerically different results between groups with a small decrease at 12 weeks, except for the SCCG, which was higher at this time. The distant area showed a continuous increase in the marked bone. CONCLUSION: The equicrestally placed implants presented little or no loss of the buccal bone wall. The subcrestally positioned implants presented loss of buccal bone, regardless of the use of bone graft. However, the buccal bone was always coronal to the implant shoulder. Both the equicrestal and subcrestal groups were benefited in the early stages of bone healing as evidenced by the fluorescence analysis.

Additional effects of aPDT on nonsurgical periodontal treatment with doxycycline in type II diabetes: a randomized, controlled clinical trial.

The association of doxycycline and periodontal treatment in non-controlled diabetes mellitus (DM) has shown positive results on clinical and metabolic parameters. Antimicrobial photodynamic therapy (aPDT) is a local and painless antimicrobial treatment that can be applied in periodontal treatment without systemic risks. The aim of this study was to evaluate the potential improvement of aPDT on clinical and metabolic effects in patients with type 2 diabetes mellitus in conjunction with nonsurgical periodontal treatment plus doxycycline. Thirty patients with type 2 diabetes and diagnosis of chronic periodontitis were treated with scaling and root planning (SRP; N = 15) or SRP plus phenothiazine chloride photosensitizer-induced aPDT (SRP + aPDT, N = 15). Patients of both groups took doxycycline (100 mg/day) for 2 weeks and plaque index, bleeding on probe (BOP), probing pocket depth (PPD), suppuration, clinical attachment level (CAL), and glycated hemoglobin levels (HbA1c) were measured at baseline and 3 months after therapy. An improvement in clinical parameters such as PPD, CAL, S, and BOP between groups was observed but without statistical significance (p > 0.05). Intragroup analysis showed a significant reduction of HbA1c (8.5 ± 0.9 to 7.5 ± 0.1, p < 0.01) in the SRP + aPDT group. The differences of HbA1c between baseline and 3 months were greater for the SRP + aPDT (11.4 %) than SRP (10 %) (0.87 ± 0.9 and 0.4 ± 0.84 respectively; p < 0.05). A single application of the aPDT as an adjunct to periodontal treatment did not show additional benefits in the clinical parameters but resulted in a slight greater decrease in HbA1c.

Buccal bone remodeling after tooth extraction using the flapless approach with and without synthetic bone grafting. A histomorphometric study in dogs.

OBJECTIVE: The aim of this study was to evaluate buccal bone remodeling of fresh sockets following tooth extraction using the flapless approach, with or without synthetic graft materials. MATERIAL AND METHODS: Eight dogs had the mandibular bicuspids extracted without flaps, and two alveoli on each side (total of 4) were selected. The following groups were devised: one socket on each side received a grafting material (test group), and the other remained only with a blood clot (control group). Ground sections were prepared from 12-week healing biopsies, and histomorphometry was performed. RESULTS: The buccal crest level (BCL) relative to the new bone (i), in the test group, showed numerically better data when compared with the control group, but without statistical relevance. The BCL relative to the old bone (ii) was very similar for the groups without statistical relevance. The alveolar ridge width (ARW) showed similar results without statistically significant difference between the groups. The total bone area (TBA) showed statistically significant differences between the test (38.60%) and control (47.18%) groups. The new bone area (NBA) presents a numerical difference between the test (15.62%) and control (22.24%), but without statistically significant differences. The old bone and the bone marrow were similar for both groups. CONCLUSION: It was observed that there was no loss of the buccal bone crest in relation to the lingual bone crest, especially in the test group.

A Randomized comparative clinical study of two surgical procedures to improve root coverage with the acellular dermal matrix graft.

AIM: This randomized, controlled, clinical study compared two surgical techniques for root coverage with the acellular dermal matrix graft (ADMG) to evaluate which procedure could provide better root coverage and greater amounts of keratinized tissue. MATERIALS AND METHODS: Fifteen pairs of bilateral Miller Class I or II gingival recessions were treated and assigned randomly to the test group, and the contra-lateral recessions were assigned to the control group. The ADMG was used in both groups. In the control group, the graft and flap were positioned at the level of the cemento-enamel junction (CEJ), and in the test group, the graft was positioned 1 mm apical to the CEJ and the flap 1 mm coronal to the CEJ. The clinical parameters were taken before the surgeries and after 6 months. The gingival recession area, a new parameter, was measured in standardized photographs through a special device and software. RESULTS: There were statistically significant differences favouring the proposed technique for all parameters except for the amount of keratinized tissue at 6 months. CONCLUSIONS: The proposed test technique is more suitable for root coverage procedures with ADMG, and the new parameter evaluated appears valuable for root coverage analysis. (Clinicaltrials.gov Identifier: NCT01175720).

Enamel matrix derivative and transforming growth factor-beta1 in Class III furcation defects. A histomorphometric study in dogs.

The objective of this study was to evaluate histomorphometrically, in dogs, the effect of enamel matrix derivative (EMD), with or without transforming growth factor-beta1 (TGF-beta1), in a periodontal Class III furcation model. Class III furcation defects were created in P3 and P4 of six dogs. The defects were allowed to stabilize for 21 days. Four experimental conditions were established: G1: control (propylene glycol alginate); G2: EMD; G3: TGF-beta1 and G4: EMD + TGF-beta1. After 12 weeks, the dogs were euthanized. Their jaws were removed, fixed, decalcified, dehydrated and embedded in paraffin. Semi-serial sections were obtained, stained and examined with light microscopy. The furcation defects were not completely closed in any specimen, with downgrowth of the junctional epithelium into the furcation area. The morphologic characteristics of the newly formed tissues in the test groups were similar to the control group, with slight differences in average values, but with no statistically significant differences between the groups. This study was not able to provide histological evidence that EMD, TGF-beta1 and EMD + TGF-beta1 present additional advantages in periodontal bone formation in a Class III furcation model in dogs.

Buccal bone plate remodeling after immediate implant placement with and without synthetic bone grafting and flapless surgery: radiographic study in dogs.

Recent studies in animals have shown pronounced resorption of the buccal bone plate after immediate implantation. The use of flapless surgical procedures prior to the installation of immediate implants, as well as the use of synthetic bone graft in the gaps represent viable alternatives to minimize buccal bone resorption and to favor osseointegration. The aim of this study was to evaluate the healing of the buccal bone plate following immediate implantation using the flapless approach, and to compare this process with sites in which a synthetic bone graft was or was not inserted into the gap between the implant and the buccal bone plate. Lower bicuspids from 8 dogs were bilaterally extracted without the use of flaps, and 4 implants were installed in the alveoli in each side of the mandible and were positioned 2.0 mm from the buccal bone plate (gap). Four groups were devised: 2.0-mm subcrestal implants (3.3 × 8 mm) using bone grafts (SCTG), 2.0-mm subcrestal implants without bone grafts (SCCG), equicrestal implants (3.3 × 10 mm) with bone grafts (ECTG), and equicrestal implants without bone grafts (ECCG). One week following the surgical procedures, metallic prostheses were installed, and within 12 weeks the dogs were sacrificed. The blocks containing the individual implants were turned sideways, and radiographic imaging was obtained to analyze the remodeling of the buccal bone plate. In the analysis of the resulting distance between the implant shoulder and the bone crest, statistically significant differences were found in the SCTG when compared to the ECTG (P = .02) and ECCG (P = .03). For mean value comparison of the resulting linear distance between the implant surface and the buccal plate, no statistically significant difference was found among all groups (P > .05). The same result was observed in the parameter for presence or absence of tissue formation between the implant surface and buccal plate. Equicrestally placed implants, in this methodology, presented little or no loss of the buccal bone. The subcrestally positioned implants presented loss of buccal bone, even though synthetic bone graft was used. The buccal bone, however, was always coronal to the implant shoulder.

The effect of a single episode of antimicrobial photodynamic therapy in the treatment of experimental periodontitis. Microbiological profile and cytokine pattern in the dog mandible.

The purpose of this study was to evaluate the effect of a single application of antimicrobial photodynamic therapy (aPDT) on microbiological profile and cytokine pattern in dogs. Periodontal disease was induced by placing 3.0 silk ligatures around the mandibular pre-molars bilaterally during 8 weeks. The dogs were randomly treated with aPDT using a dye/laser system, scaling and root planning (SRP), or with the association of treatments (SRP + aPDT). Plaque samples were collected at baseline, 1, 3, and 4 weeks, and the mean counts of 40 species were determined using DNA-DNA hybridization. Gingival biopsies were removed and the expression of tumor necrosis factor alpha (TNF-α), receptor activator of NF-kB ligand (RANKL), osteoprotegerin (OPG), matrix metalloproteinase (MMP-1), interleukin (IL) 6, IL-10 and total bacterial load by analysis of 16 S rRNA gene were evaluated through real-time PCR. The results shows that the levels of the majority of the species were reduced 1 week post-therapy for all treatments, however, an increase in counts of Prevotella intermedia (p = 0.00), Prevotella. nigrescens (p = 0.00) and Tannerella forsythia (p = 0.00) was observed for aPDT and SRP + aPDT. After 4 weeks, a regrowth of Porphyromonas gingivalis (p = 0.00) and Treponema denticola (p = 0.00), was observed for all treatments. Also, a strikingly reduction of counts on counts of Aggregatibacter actinomycetemcomitans was observed for the aPDT (p = 0.00). For the cytokine pattern, the results were similar for all treatments, and a reduction in the expression of cytokines and bacterial load was observed throughout the study. Our results suggest that SRP, aPDT in a single application, and SRP + aPDT affects different bacterial species and have similar effects on the expression of cytokines evaluated during the treatment of ligature-induced periodontitis.

Potential of bioactive glass particles of different size ranges to affect bone formation in interproximal periodontal defects in dogs.

BACKGROUND: The aim of this study was to compare the potential of bioactive glass particles of different size ranges to affect bone formation in periodontal defects, using the guided tissue regeneration model in dogs. METHODS: In six dogs, 2-wall intrabony periodontal defects were surgically created and chronified on the mesial surfaces of mandibular third premolars and first molars bilaterally. After 1 month, each defect was randomly assigned to treatment with bioabsorbable membrane in association with bioactive glass with particle sizes between 300 and 355 microm (group 1) or between 90 and 710 microm (group 2), membrane alone (group 3), or negative control (group 4). The dogs were sacrificed 12 weeks after surgeries, and histomorphometric measurements were made of the areas of newly formed bone, new mineralized bone, and bioactive glass particle remnants. RESULTS: With regard to the area of bioactive glass particle remnants, there was a statistically significant difference between groups 1 and 2, favoring group 1. There were greater areas of mineralized bone in groups 1 and 2 compared to groups 3 and 4 (P <0.05). CONCLUSION: The bioactive glass particles of small size range underwent faster resorption and substitution by new bone than the larger particles, and the use of bioactive glass particles favored the formation of mineralized bone.

Comparison between two surgical techniques for root coverage with an acellular dermal matrix graft.

AIM: The aim of this randomized, controlled, clinical study was to compare two surgical techniques with the acellular dermal matrix graft (ADMG) to evaluate which technique could provide better root coverage. MATERIAL AND METHODS: Fifteen patients with bilateral Miller Class I gingival recession areas were selected. In each patient, one recession area was randomly assigned to the control group, while the contra-lateral recession area was assigned to the test group. The ADMG was used in both groups. The control group was treated with a broader flap and vertical-releasing incisions, and the test group was treated with the proposed surgical technique, without releasing incisions. The clinical parameters evaluated before the surgeries and after 12 months were: gingival recession height, probing depth, relative clinical attachment level and the width and thickness of keratinized tissue. RESULTS: There were no statistically significant differences between the groups for all parameters at baseline. After 12 months, there was a statistically significant reduction in recession height in both groups, and there was no statistically significant difference between the techniques with regard to root coverage. CONCLUSIONS: Both surgical techniques provided significant reduction in gingival recession height after 12 months, and similar results in relation to root coverage.

Subepithelial connective tissue graft for root coverage in smokers and non-smokers: a clinical and histologic controlled study in humans.

BACKGROUND: The aim of this study was to evaluate root coverage of gingival recessions and to compare graft vascularization in smokers and non-smokers. METHODS: Thirty subjects, 15 smokers and 15 non-smokers, were selected. Each subject had one Miller Class I or II recession in a non-molar tooth. Clinical measurements of probing depth (PD), relative clinical attachment level (CAL), gingival recession (GR), and width of keratinized tissue (KT) were determined at baseline and 3 and 6 months after surgery. The recessions were treated surgically with a coronally positioned flap associated with a subepithelial connective tissue graft. A small portion of this graft was prepared for immunohistochemistry. Blood vessels were identified and counted by expression of factor VIII-related antigen-stained endothelial cells. RESULTS: Intragroup analysis showed that after 6 months there a was gain in CAL, a decrease in GR, and an increase in KT for both groups (P <0.05), whereas changes in PD were not statistically significant. Smokers had less root coverage than non-smokers (58.02% +/- 19.75% versus 83.35% +/- 18.53%; P <0.05). Furthermore, the smokers had more GR (1.48 +/- 0.79 mm versus 0.52 +/- 0.60 mm) than the non-smokers (P <0.05). Histomorphometry of the donor tissue revealed a blood vessel density of 49.01 +/- 11.91 vessels/200x field for non-smokers and 36.53 +/- 10.23 vessels/200x field for smokers (P <0.05). CONCLUSION: Root coverage with subepithelial connective tissue graft was negatively affected by smoking, which limited and jeopardized treatment results.

Effects of periodontal therapy on glycemic control and inflammatory markers.

BACKGROUND: Periodontitis, a complication of diabetes mellitus (DM), can induce or perpetuate systemic conditions. This double-masked, placebo-controlled study evaluated the effects of periodontal therapy (scaling and root planing [SRP]) on the serum levels of glycated hemoglobin (HbA1c) and on inflammatory biomarkers. METHODS: Thirty subjects with type 2 DM and periodontitis were treated with SRP + placebo (SRP; N = 15) or with SRP + doxycycline (SRP+Doxy; N = 15), 100 mg/day, for 14 days. Clinical and laboratory data were recorded at baseline and at 3 months after treatment. RESULTS: After 3 months, the reduction in probing depth was 0.8 mm for the SRP group (P <0.01) and 1.1 mm for the SRP+Doxy group (P <0.01) followed by a 0.9% (SRP; P = 0.17) and 1.5% (SRP+Doxy; P <0.01) reduction in HbA1c levels. A significant reduction in interleukin (IL)-6; interferon-inducible protein 10; soluble fas ligand; granulocyte colony-stimulating factor; RANTES; and IL-12 p70 serum levels were also verified (N = 30). To our knowledge, this is the first report on the effects of periodontal therapy on multiple systemic inflammatory markers in DM. CONCLUSIONS: Periodontal therapy may influence the systemic conditions of patients with type 2 DM, but no statistical difference was observed with the adjunctive systemic doxycycline therapy. Moreover, it is possible that the observed improvement in glycemic control and in the reduction of inflammatory markers could also be due to diet, which was not controlled in our study. Therefore, a confirmatory study with a larger sample size and controlled diet is necessary.

Comparison of two surgical procedures for use of the acellular dermal matrix graft in the treatment of gingival recessions: a randomized controlled clinical study.

BACKGROUND: The aim of this randomized, controlled, clinical investigation was to compare two surgical techniques for root coverage with the acellular dermal matrix graft to evaluate which technique provided better root coverage, a better esthetic result, and less postoperative discomfort. METHODS: Fifteen patients with bilateral Miller Class I or II gingival recessions were selected. Fifteen pairs of recessions were treated and assigned randomly to the test group, and the contralateral recessions were assigned to the control group. The control group was treated with a broader flap and vertical releasing incisions; the test group was treated with the proposed surgical technique, without vertical releasing incisions. The clinical parameters evaluated were probing depth, relative clinical attachment level, gingival recession (GR), width of keratinized tissue, thickness of keratinized tissue, esthetic result, and pain evaluation. The measurements were taken before the surgeries and after 6 months. RESULTS: At baseline, all parameters were similar for both groups. At 6 months, a statistically significant greater reduction in GR favored the control group. The percentage of root coverage was 68.98% and 84.81% for the test and control groups, respectively. The esthetic result was equivalent between the groups, and all patients tolerated both procedures well. CONCLUSIONS: Both techniques provided significant root coverage, good esthetic results, and similar levels of postoperative discomfort. However, the control technique had statistically significantly better results for root coverage of localized gingival recessions.

Histologic analysis of the acellular dermal matrix graft incorporation process: a pilot study in dogs.

Clinical results with acellular dermal matrix graft (ADMG) in periodontal surgeries suggest that the material is incorporated by the host tissues. However, histologic studies of the ADMG incorporation process are limited. The objective of this study was to evaluate the incorporation of ADMG into gingival tissues in a dog model. Gingival recession-type defects were created at the canines of six dogs. After 6 weeks, periodontal surgeries to repair the defects were performed using ADMG. Two animals each were sacrificed after 4, 8, and 12 weeks. At 4 weeks, thick collagen fibers from the ADMG were clearly seen in the connective tissue, and some blood vessels were penetrating into the ADMG. At 8 weeks, blood vessel penetration was enhanced, and collagen fiber bundles from the ADMG were seen sending branches into the connective tissue in all directions. After 12 weeks, the ADMG and the connective tissue seemed to be well integrated into a single highly vascularized structure, indicating almost complete incorporation of the ADMG.

Effects of granule size on the osteoconductivity of bovine and synthetic hydroxyapatite: a histologic and histometric study in dogs.

Two bovine hydroxyapatites (BHAs), one with granule size of 150 to 200 microm and one with granule size of 300 to 329 micro, and 2 synthetic hydroxyapatites (SHAs), with granule size of 150 and 300 microm, respectively, were compared for effectiveness in repairing circumferential bone defects in dogs. The hydroxyapatites (HAs) were characterized through powder x-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). Three trephined bone defects (5.0 mm wide x 4 mm long) were created in the humeruses of 8 dogs. In a random manner, the defects on each side were treated with either BHA with small granules (BHA[s]), BHA with large granules (BHA[L]), SHA with small granules (SHA[s]), SHA with large granules (SHA[L]), or left to heal unaided (bilateral control). Four dogs were sacrificed after 6 and 12 postoperative weeks, respectively. Ground sections of each defect were submitted to histologic and histomorphometric analysis (percentage of area occupied by bone, bone marrow, and biomaterial). As a rule, the HA granules exhibited direct bone contact, regardless of the origin and the size of the granules. Control sites were related and had an increased amount of connective tissue infiltration. At 12 weeks, BHA(s) exhibited improved bone formation compared with SHA(s) and SHA(L). The SHA(s) delivered reduced amounts of bone compared with the remaining groups (control included). The area of bone measured in BHA(s) sites was significantly higher at 12 weeks than 6 weeks. The XRD revealed the tested HA samples to be highly crystalline, while BHA appeared with rougher surface at SEM analysis. The BHA(s) performed better than the SHA(s) and SHA(L), as assessed by the amount of bone measured in both implantation sites at 12 weeks. The BHA's material characteristic itself rather than granules size accounted for the distinctive biological behavior. The increased roughness of the BHAs' surface, as assessed through SEM, seemed to benefit the osteoconduction process.

Treatment of Class III furcation defects with expanded polytetrafluoroethylene membrane associated or not with anorganic bone matrix/synthetic cell-binding peptide: a histologic and histomorphometric study in dogs.

BACKGROUND: Up until now, no predictable periodontal regeneration of Class III furcation defects has been demonstrated after treatment with different available techniques. Recently, a bone graft enriched with a peptide was developed and has shown satisfactory results when applied in intrabony defects. The aim of this study was to compare the use of expanded polytetrafluoroethylene (ePTFE) membrane associated (test group) or not (control group) with anorganic bovine-derived bone matrix (ABM)/synthetic peptide, in the treatment of Class III furcation defects in dogs. METHODS: Six mongrel dogs were used in this study, and the second and fourth mandibular lower premolars were extracted. Class III furcation defects were surgically created in the third premolars and filled with impression material. Afterwards, the defects were surgically assessed for debridement and root planing. Teeth were randomly assigned into test and control groups. The membranes were removed after 4 weeks, and the animals were sacrificed 12 weeks later. RESULTS: Comparisons between groups by the Wilcoxon signed rank test showed no statistically significant differences in the parameters evaluated. In the control group, a new bone area (NBA) of 41.71%+/-24.07%, connective tissue area (CTA) of 36.34%+/-15.50%, and epithelium tissue area (ETA) of 9.39%+/-5.85% were observed. The new cementum extension (NCE) was 24.16%+/-13.18%. The test group presented an NBA of 31.84%+/-12.58%, CTA of 47.72%+/-11.33%, ETA of 9.17%+/-6.81%, and an NCE of 30.13%+/-16.43%. CONCLUSION: There was no statistically significant difference between the two therapies: ePTFE membrane associated with ABM/synthetic peptide flow or ePTFE membrane only.

Anorganic bovine matrix/p-15 "flow" in the treatment of periodontal defects: case series with 12 months of follow-up.

BACKGROUND: Nowadays there is a trend in developing biologic modalities that may enhance wound healing of specific sites. In this regard, a cell-binding activity of type I collagen provided by a synthetic peptide (P-15) was incorporated in a scaffold (anorganic bovine matrix [ABM]) to facilitate the attachment, migration, and differentiation of cells. This case series describes a surgical protocol for the placement of ABM/P-15 "flow" during regenerative procedures. METHODS: Wide periodontal defects were treated with sulcular incisions preserving the papillae, full-thickness flap reflection, granulation tissue debridement, mechanical and chemical root surface treatment, placement of the ABM/P-15 "flow," and wound-closure sutures. Weekly, and then monthly, deplaquing was performed until the 12-month postoperative recall, in which the clinical parameters were reevaluated. RESULTS: Significant clinical changes, including probing depth reduction and relative clinical attachment level gain, were achieved after the 12-month period. The radiographs demonstrated increase in radiopacity when compared to those taken initially, suggesting hard tissue improvements. CONCLUSIONS: The topography of the defects described here could be understood as a challenge for regeneration, once the previous breakdown of the supporting tissues had diminished the source of cells for the healing process and reduced the number of residual walls to retain the graft material. Thus, it seems that the ABM/P-15 "flow" contributed to the clinical success achieved. Based on this result, ABM/P-15 "flow" could be a useful and beneficial material for the treatment of periodontal defects.

Effect of early membrane removal on regeneration of Class II furcation defects in dogs.

BACKGROUND: This study evaluated the influence of early removal of an expanded polytetrafluoroethylene (ePTFE) membrane on periodontal regeneration. METHODS: The third and fourth mandibular bicuspids of six healthy mongrel dogs were used. Class II furcation lesions were surgically created making lesions chronic for 21 days. Full flaps were elevated, and ePTFE membranes were adapted over the defects. The membranes were removed at 2 weeks on the experimental sides (test group [TGr]) and at 4 weeks on the control side (control group [CGr]). The dogs were sacrificed 12 weeks following placement of the membranes, and the teeth were histologically processed. Area measurements of new tissue (NT), epithelium (EP), connective tissue (CT), and new bone (NB) and linear measurements of bone height (BH) and new cementum (NC) were made. Wilcoxon signed rank test (P <0.05; N = 6) was carried out to determine differences between groups. RESULTS: The area measurements (in mm2) for TGr and CGr, respectively, were as follows: 14.32 +/- 4.01 and 12.46 +/- 3.54 (NT); 0.04 +/- 0.09 and 0.01 +/- 0.04 (EP); 2.31 +/- 2.60 and 1.91 +/- 2.96 (CT); and 9.56 +/- 3.77 and 8.79 +/- 2.99 (NB). The results of the linear measurements (in mm) for TGr and CGr, respectively, were as follows: 3.85 +/- 1.21 and 4.03 +/- 0.94 (BH) and 10.91 +/- 1.72 and 10.59 +/- 1.80 (NC). There were no statistically significant differences between TGr and CGr for any measurement. CONCLUSION: The early removal of ePTFE membranes in Class II furcation defects in dogs did not affect periodontal regeneration.

Crestal bone loss minimized when following the crestal preparation protocol: a histomorphometric study in dogs.

Initial breakdown of the implant-tissue interface generally begins at the crestal region in successfully osseointegrated implants. The purpose of this study was to evaluate the effect on crestal bone loss (CBL) around implants specially developed for immediate loading with a unique crestal drill. After 8 weeks postextraction, 6 young male mongrel dogs received 48 implants (XiVE) in the region corresponding to the 4 mandibular premolars. The implant sites were prepared according to the manufacturer's protocol with conventional standard drills. Before implant placement, the crestal drill was used in the experimental group but not in the control group. After a healing period of 12 weeks, the dogs were sedated and euthanized. Through linear measurements, from the top of the implant to the first bone-implant contact, the amount of CBL was determined. The histomorphometric results of CBL (mean +/- SEM) were 0.88 +/- 0.13 mm (range 0.0-3.0 mm) in the experimental group and 1.69 +/- 0.17 mm (range 0.0-4.2 mm) in the control group. The difference was statistically significant (P < .05) when the implants were used as the experimental units. The statistical analysis also revealed significance when the dogs were used as the experimental units (P < .05). When the median was used for analyses, the CBL was 0.44 mm for the experimental group and 1.91 mm for the control group. Crestal bone loss was minimized when the crestal preparation protocol was carefully followed by using the osseocondensating XiVE implant system.