Anti-Fibronectin Aptamer Modifies Blood Clot Pattern and Stimulates Osteogenesis: An Ex Vivo Study.

BACKGROUND: Scaffold (SCA) functionalization with aptamers (APT) provides adsorption of specific bioactive molecules on biomaterial surfaces. The aim of this study was to observe if SCA enriched with anti-fibronectin APT can favor coagulum (PhC) and osteoblasts (OSB) differentiation. METHODS: 20 µg of APT was functionalized on SCA by simple adsorption. For PhC formation, SCAs were inserted into rat calvaria defects for 17 h. Following proper transportation (buffer solution PB), OSBs (UMR-106 lineage) were seeded over PhC + SCAs with and without APT. Cells and PhC morphology, PhC cell population, protein labeling and gene expression were observed in different time points. RESULTS: The APT induced higher alkaline phosphatase and bone sialoprotein immunolabeling in OSB. Mesenchymal stem cells, leukocytes and lymphocytes cells were detected more in the APT group than when scaffolds were not functionalized. Additionally, an enriched and dense fibrin network and different cell types were observed, with more OSB and white blood cells in PhC formed on SCA with APT. The gene expression showed higher transforming growth factor beta 1 (TGF-b1) detection in SCA with APT. CONCLUSIONS: The SCA functionalization with fibronectin aptamers may alter key morphological and functional features of blood clot formation, and provides a selective expression of proteins related to osteo differentiation. Additionally, aptamers increase TGF-b1 gene expression, which is highly associated with improvements in regenerative therapies.

Root coverage using coronally advanced flap with porcine-derived acellular dermal matrix or subepithelial connective tissue graft: a randomized controlled clinical trial.

OBJECTIVE: The aim of this study is to investigate the use of a porcine-derived acellular dermal matrix (MD) in root coverage procedures combined with extended coronally positioned flap (eCAF), in comparison to the subepithelial connective tissue graft (SCTG) associated with the eCAF. MATERIAL AND METHODS: Eighteen adult patients presenting bilateral type 1 gingival recession were randomly assigned to SCTG or MD groups. Clinical and patient-based outcomes were recorded at 3 and 6 months after the surgical procedure. RESULTS: Both groups showed a significant reduction in the mean recession height of 3.33 ± 0.89 mm to 1.24 ± 1.10 mm (MD) and 3.21 ± 0.8 mm to 0.83 ± 0.86 mm (SCTG) without difference between groups. Six patients in the test group and eight in the control group obtained complete root coverage. The keratinized tissue height and thickness (KTT) showed a significant increase after 3 and 6 months in both groups. The average KTT gains were 0.39 ± 0.4 mm (MD) and 0.51 ± 0.5 mm (SCTG) (p < 0.05). Performing multivariate analysis suggests that MD addition to coronally advanced flaps may be similar to SCTG. CONCLUSION: The MD had similar results in comparison to SCTG and in the context of reducing patient morbidity it can be used as an alternative for the treatment of gingival recessions. CLINICAL RELEVANCE: The SCTG is the gold standard therapy for root coverage. The MD has been widely used in mucogingival surgery as a substitute for SCTG and proposed similar results. A substitute is very important for clinicians and patients. It will give a better postoperative and possibilities to treat multiples recession. (Clinicaltrials.gov Identifier: NCT03675334).

Root coverage of gingival recessions with non-carious cervical lesions: a controlled clinical trial.

OBJECTIVE: The non-carious cervical lesion (NCCL) is commonly produced by improper toothbrushing techniques, occlusion trauma, anatomic mal-positioned teeth, and acid erosion, thus sharing the same etiology of gingival recession (GR). The association of a graft to the coronally advanced flap had demonstrated the best long-term outcome for root coverage (RC). However, substitutes for the autogenous graft must be studied. This split-mouth clinical trial investigates the RC and the increase in keratinized tissue (KT) when comparing RC of NCCLs associated with GR with intact roots using an extended coronally advanced flap (ECAF) associated with the acellular dermal matrix graft (ADMG), a connective tissue replacement graft. MATERIAL AND METHODS: Seventeen individuals with bilateral GR were included in the study. One side had a NCCL (TG) and the opposite root was intact (CG). All patients were treated with the ECDF associated with ADMG. All clinical parameters were assessed at baseline and 6 months postoperative. RESULTS: Root coverage means (CG, 69.5 ± 19 and TG. 72.2 ± 16.5; p value = 0.849570) were not significantly different between control and test groups. In addition, the KT had an increase in the follow-up period for both groups. CONCLUSION: GR associated with NCCLs can be successfully treated with the ECDF and ADMG. CLINICAL RELEVANCE: Patients frequently search for GR treatment due to cervical wear, root sensitivity, and compromising aesthetics. The NCCL participates with the same issues. The present study contributes to the literature that GR associated with NCCLs can be successfully treated with the ECAF and the ADMG.

Association between Genetic Polymorphisms in RANK, RANKL and OPG and Peri-Implant Diseases in Patients from the Amazon Region.

The present study evaluated polymorphisms in RANK, RANKL and OPG-encoding genes to assess whether they are associated with mucositis and peri-implantitis in a population from the Brazilian Amazon region. One hundred and fourteen patients with dental implants were included in the study. After clinical and radiographic examination, the sample was categorized into 4 groups, according to the peri-implant status: Healthy (n=71), Mucositis (n=30), Peri-implantitis (n=13) and Diseased (Mucositis + Peri-implantitis, n=43). Genomic DNA was extracted from buccal cells from saliva, and the genetic polymorphism in osteoprotegerin (OPG), Kappa nuclear factor activator receptor (RANKL) and nuclear kappa factor activator receptor (RANK) were genotyped by the real time PCR. Univariate and multivariate statistical analyses were performed to compare clinical variables among groups and to evaluate genotypes and alleles distributions and the established alpha was 5%. Age, peri-implant biotype, diabetes and presence of peri-implant biofilm were associated with mucositis (p<0.05) and peri-implantitis (p<0.05). Smoking, alcoholism, and periodontal biofilms were also associated with the presence of peri-implantitis (p<0.05). Univariate and multivariate analysis did not demonstrate an association of peri-implantitis or mucositis with any genetic polymorphism in RANK (rs3826620), RANKL (rs9594738) and OPG (rs2073618) (p>0.05). The studied genetic polymorphism in RANK, RANKL and OPG were not associated with mucositis and peri-implantitis in a Brazilian population from the Amazon region.

Experimental and clinical studies on plastic periodontal procedures.

We have compiled, in this Periodontology 2000 review, all Latin American literature on experimental and clinical studies of periodontal plastic procedures. The body of literature on this subject has led to a discussion of the features and treatment outcomes of root-coverage procedures. Over time, knowledge on periodontal plastic procedures has become less empirical and more supportive of the clinical management of recession-type defects. Gingival recession etiology, animal studies, free gingival grafts, pedicle flaps (semilunar, laterally positioned, and coronally positioned), and subepithelial connective tissue grafts are extensively reviewed. The use of allografts as an alternative to subepithelial connective tissue grafts, the treatment of multiple gingival recessions, and the rationale for use of guided tissue regeneration and enamel matrix derivative in plastic periodontal procedure is discussed. We also assess how smoking can affect the treatment outcomes in plastic surgery procedures. Minimally invasive procedures are of great value in improving the features of the final tissues. The following aspects identified in this compilation were of great interest: (a) some factors, anatomical in nature, favor the formation of root recessions, but it is the inflammatory process (caused by the presence of biofilm and/or by traumatic toothbrushing) that is responsible for the development of root recessions; and (b) pedicle flap procedures (especially the coronally positioned flap) are extremely versatile and have the most predictable outcome of all root-coverage procedures, especially when combined with subepithelial connective tissue grafting and/or allogeneic grafts. In summary: subepithelial connective tissue grafting is considered as the first option to augment gingival width and thickness, and it may provide better long-term results; the same principles of root-coverage procedures in individual sites appear be used in clinical practice also for multiple-recession type defects; an allograft is an efficient alternative to a subepithelial connective tissue graft and, when it is the treatment option of choice, the use of wide, extended flaps should be considered; because of the superiority of plastic periodontal procedures over guided tissue regeneration and the technical difficulty of the latter, guided tissue regeneration has become obsolete for root-coverage procedures; there is rather a large body of evidence attesting that smoking negatively influences root-coverage procedures, especially subepithelial connective tissue grafts; and minimally invasive techniques may be of great value for improving the results obtained with plastic periodontal procedures, but these techniques need to be better addressed in clinical trials, both in terms of the quality and quantity of the new tissue generated.

Antimicrobial photodynamic therapy as adjunct to non-surgical periodontal treatment in smokers: a randomized clinical trial.

OBJECTIVES: This study aims to investigate the additional influence of multiple applications of antimicrobial photodynamic therapy (aPDT) in smokers with chronic periodontitis. MATERIALS AND METHODS: Twenty smokers with chronic periodontitis were treated in a split-mouth design study with aPDT adjunct to Scaling and Root Planing (SRP) or SRP. aPDT was performed by using a laser light source with 660 nm wavelength associated with a photosensitizer. The applications were performed in four episodes (at days 0, 2, 7, and 14). All patients were monitored for 90 days. Plaque index, probing depth, clinical attachment level, and bleeding on probing were performed at baseline, 30, and 90 days after the SRP. Gingival crevicular fluid and subgingival plaque samples were collected for immunological and microbiological analysis, respectively. Data obtained were statistically analyzed. RESULTS: aPDT as an adjunct to SRP did not demonstrate statistically significant advantages on clinical parameters when compared with SRP alone. No statistic significant differences between groups were observed (p < 0.05). Levels of anti-inflammatory cytokines and bacterial species were comparable in both groups at day 90 after treatment. CONCLUSION: Periodontal treatment with SRP + aPDT in multiples episodes was not able to promote additional clinical, immunological, and microbiological benefits in smokers when compared SRP alone in patients with chronic periodontitis. CLINICAL RELEVANCE: Multiple episodes of aPDT adjunctive to non-surgical treatment did not improve significantly the clinical, immunological, and microbiological parameters when compared with SRP alone. More randomized clinical trials are needed to evaluate adjuvant therapies for scaling and root planning in smokers with chronic periodontitis. ClinicalTrials.gov Identifier: NCT03039244.

Microbiologic effect of two topical anti-infective treatments on ligature-induced peri-implantitis: A pilot study in dogs.

BACKGROUND: The aim of this split-mouth design pilot study in dogs was to assess microbiologic effects of two topical anti-infective treatment protocols on dental implants subjected to ligature-induced peri-implantitis, without use of systemic antibiotics. METHODS: Eight adult Beagle dogs each received four dental implants in contralateral, edentulated, mandibular jaw quadrants. After 8 weeks, silk ligatures were installed, to be removed after another 8 weeks. After 6 additional weeks, induced peri-implantitis lesions were subjected to either antimicrobial photodynamic therapy (aPDT) or a topical tetracycline (TTC) hydrochloride (50 mg/mL) solution. Microbiologic samples were collected from the deepest proximal peri-implantitis site in each jaw quadrant before and after treatment. The samples were analyzed using DNA-DNA hybridization checkerboard technique. RESULTS: Peri-implantitis induction successfully produced lesions with microbiologic characteristics similar to those found in humans. Overall results showed effective bacterial count reductions for both protocols. aPDT demonstrated major reductions of the red complex, but no statistical differences between groups were observed when adjusted for multiple comparisons. CONCLUSION: aPDT and TTC successfully decontaminated infected implant surfaces. Implant decontamination with aPDT appears to be a viable alternative to TTC in the management of peri-implantitis infection.

Effects of local administration of tiludronic acid on experimental periodontitis in diabetic rats.

BACKGROUND: Tiludronic acid (TIL) presents antiresorptive and anti-inflammatory properties and has not been evaluated in the periodontitis-diabetes mellitus (DM) association to date, to the best knowledge of the authors. This study evaluates effects of local administration of TIL on experimental periodontitis (EP) in rats with streptozotocin-induced DM. METHODS: Thirty-two animals (Rattus norvegicus albinus, Wistar) were divided into groups DM/C (Control), DM/EP, DM/EP/TIL1, and DM/EP/TIL3. In EP groups, a ligature was placed around mandibular first molars. In groups DM/EP/TIL1 and DM/EP/TIL3, TIL solutions (1 and 3 mg/kg, respectively) were injected into the gingival tissue of mandibular molars every other day for 10 days, until euthanasia. Periodontal tissues were analyzed by microcomputed tomography (micro-CT), histomorphometry, immunohistochemistry (tartrate-resistant acid phosphatase [TRAP], receptor activator of nuclear factor-κB ligand [RANKL], osteoprotegerin, cleaved caspase 3), and quantitative reverse transcription-polymerase chain reaction (interleukin [IL]-1ß, vascular endothelial growth factor [VEGF]). RESULTS: In micro-CT analyses, groups DM/EP/TIL1 and DM/EP/TIL3 presented reduced alveolar bone resorption (P < 0.05). Group DM/EP/TIL3 presented decreased attachment loss (P < 0.05). The amount of TRAP-positive multinucleated cells was decreased in TIL groups (P < 0.05). Group DM/EP/TIL3 presented a lower immunolabeling pattern for RANKL (P < 0.05). TIL treatment decreased genic expression of IL-1ß, and in group DM/EP/TIL3, expression of VEGF was increased (P < 0.05). CONCLUSION: Local administration of TIL promoted a protective effect against tissue destruction in EP in diabetic rats, and the dosage of 3 mg/kg of TIL promoted the best results regarding its antiresorptive and anti-inflammatory effects.

Comparison between two antimicrobial protocols with or without guided bone regeneration in the treatment of peri-implantitis. A histomorphometric study in dogs.

OBJECTIVES: This study used a dog model to evaluate two antimicrobial protocols with or without guided bone regeneration (GBR) in the surgical reconstruction of peri-implantitis defects. MATERIAL AND METHODS: Eight beagle dogs subject to ligature-induced peri-implantitis were used. The animals either received antimicrobial photodynamic therapy or topical tetracycline hydrochloride combined with GBR or as stand-alone surgical interventions. Block biopsies of the defect sites for histological analysis were obtained at euthanasia, 12 weeks postsurgery. The primary outcome of the study was re-osseointegration; secondary outcomes included alveolar bone gain and remaining defect characteristics. The effects of the implant site, early exposure, and type of antimicrobial protocol on bone regeneration were also evaluated. RESULTS: No significant differences were observed between the two antimicrobial protocols, and the adjunctive use of GBR failed to significantly improve re-osseointegration or bone gain using either protocol. Buccal sites and implant early exposure negatively affected bone regeneration. CONCLUSION: Both antimicrobial therapies stand-alone or combined with GBR allowed similar and limited bone gain.

The effect of a flapless alveolar ridge preservation procedure with or without a xenograft on buccal bone crest remodeling compared by histomorphometric and microcomputed tomographic analysis.

OBJECTIVES: This study evaluated buccal bone crest remodeling, socket composition after healing, and dimensional ridge preservation after flapless tooth extraction procedures with or without a xenograft comparing histomorphometric and microcomputed tomographic (micro-CT) data. MATERIAL AND METHODS: The mandibular premolars of eight dogs were extracted without flaps. One socket on each side received a grafting material (test group), and the other remained only with a blood clot (control group). Twelve weeks after treatment, buccal bone crest, alveolar ridge dimensions, and composition were analyzed by histomorphometry and micro-CT. RESULTS: Two- and three-dimensional evaluations showed better results for the grafted group when compared to the non-grafted group. CONCLUSION: The flapless alveolar ridge preservation procedure with deproteinized bovine bone material enhanced buccal bone crest, alveolar ridge dimensions and bone formation when compared to sockets with the blood clot only, as observed by histomorphometric and micro-CT analysis.

Comparison between one-session root canal treatment with aPDT and two-session treatment with calcium hydroxide-based antibacterial dressing, in dog's teeth with apical periodontitis.

To evaluate one-session endodontic treatment with aPDT and two-session treatment with calcium hydroxide (CH)-based dressing in dog's teeth with apical periodontitis. After experimental induction of apical periodontitis, 48 teeth were randomly assigned to the following groups: groups OS/aPDT120d and OS/aPDT180d (one-session treatment with aPDT) and groups TS/CH120d and TS/CH180d (two-session treatment with CH-based dressing-control groups). The animals were euthanized after 120 and 180 days. After histotechnical processing, microscopic and radiographic analyses were performed. Data were analyzed by Kruskal-Wallis and Fisher's exact tests (α = 0.05). Groups TS/CHs presented repaired resorbed cemental areas, with collagen bundles and few inflammatory cells. In groups OS/aPDTs, the areas of cemental resorption were not repaired with reduced presence of cells and fibers. In the analysis of the apical closure, fluorescence microscopy and percentage of radiographic reduction of lesions, there was significant difference between groups TS/CH120d and OS/aPDT120d and between TS/CH180d and OS/aPDT180d (p < 0.05). Groups TS/CHs had weak RANKL expression and positive immunostaining for RANK and OPG. In OS/aPDT120d, there was positive immunostaining for RANKL. In OS/aPDT180d, the three osteoclastogenesis markers were expressed. The results using aPDT were worse than those obtained with two-session endodontic treatment using a CH-based dressing in teeth with apical periodontitis.

Adjunctive effect of antimicrobial photodynamic therapy in induced periodontal disease. Animal study with histomorphometrical, immunohistochemical, and cytokine evaluation.

Scaling and root planing (SRP) may not always be effective in preventing periodontal disease (PD) progression. The aim of this study was to evaluate the adjunctive effect of antimicrobial photodynamic therapy (aPDT) to SRP on induced PD in rats, analyzing histomorphometrical, immunohistochemical, and immunoenzymatic parameters. Ligatures were placed around the first mandibular molars and second maxillary molars of 60 rats to induce PD. After 14 days, they were removed and the animals were divided into six groups, with nine animals each: G1 = no treatment, G2 = SRP, G3 = light-emitting diode (LED), G4 = SRP + aPDT, G5 = aPDT, and G6 = erythrosine. The animals were euthanized after 3, 7, and 15 days. There were also two control groups (n = 3): without PD (WPD) induction and with maximum PD (PD+). In the histomorphometrical analysis of linear bone loss, G4 showed a statistically significant difference from the other experimental groups after 3 and 15 days. The tartrate-resistant acid phosphatase (TRAP)-positive cell counting was significantly lower in G4 when compared to G2 and PD+ after 3 days. Immunoenzymatic assay shows the values of the ratio (RANKL/OPG × 100). The lowest value is from the WPD group, and the group that received the SRP + aPDT treatment tended to approach this value over time. After 3 days, statistically significant differences were observed between G4 and all other experimental groups, as well as versus PD+ (one-way ANOVA + Tukey's post hoc test were performed, p < 0.05). It was concluded that the adjunctive use of aPDT in combination with SRP showed the best therapeutic results in the treatment of periodontal disease in rats.

A Randomized Comparative Study of Two Techniques to Optimize the Root Coverage Using a Porcine Collagen Matrix.

The aim of this randomized controlled clinical study was to compare the extended flap technique (EFT) with the coronally advanced flap technique (CAF) using a porcine collagen matrix (PCM) for root coverage. Twenty patients with two bilateral gingival recessions, Miller class I or II on non-molar teeth were treated with CAF+PCM (control group) or EFT+PCM (test group). Clinical measurements of probing pocket depth (PPD), clinical attachment level (CAL), recession height (RH), keratinized tissue height (KTH), keratinized mucosa thickness (KMT) were determined at baseline, 3 and 6 months post-surgery. At 6 months, the mean root coverage for test group was 81.89%, and for control group it was 62.80% (p<0.01). The change of recession depth from baseline was statistically significant between test and control groups, with an mean of 2.21 mm gained at the control sites and 2.84 mm gained at the test sites (p=0.02). There were no statistically significant differences for KTH, PPD or CAL comparing the two therapies. The extended flap technique presented better root coverage than the coronally advanced flap technique when PCM was used.

Palatal harvesting technique modification for better control of the connective tissue graft dimensions.

Subepithelial connective tissue graft (SCTG) has been extensively used for a variety of clinical applications. However, the surgical procedure may not allow control of graft thickness. The purpose of this case series is to illustrate a modification to the single incision palatal harvesting technique in order to control the SCTG thickness without increasing patient discomfort. Fifty cases from thirty systemically and periodontally healthy patients with at least one multiple gingival recession were treated with coronally advanced flaps combined with a SCTG. The palatal area served as the donor site, from where a single perpendicular incision was made to obtain a full thickness flap. Next, 1-2 mm of the flap was elevated and dissected to obtain a partial thickness flap. The graft remained attached to the full-partial thickness flap. After determining the desired SCTG thickness, the graft was harvested from the palatal flap. The patients healed uneventfully at 7 days postoperatively and primary closure was obtained for all palatal donor sites. The SCTG length and width varied depending on the needs of each case, but the SCTG thickness was well controlled with only 0.24 mm standard deviation. The suggested modification granted control of the SCTG dimensions and achieved complete wound closure within a week.

Early peri-implant endosseous healing of two implant surfaces placed in surgically created circumferential defects. A histomorphometric and fluorescence study in dogs.

OBJECTIVE: Several implant surfaces are being developed, some in the nanoscale level. In this study, two different surfaces had their early healing properties compared in context of circumferential defects of various widths. MATERIAL AND METHODS: Six dogs had the mandibular premolars extracted. After 8 weeks, four implants were placed equicrestally in each side. One acted as control, while the others were inserted into sites with circumferential defects of 1.0, 1.5 and 2.0 mm wide and 5 mm deep. A nano-modified surface was used on one side and a micro-rough on the other. Bone markers were administered on the third day after implant placement and then after 1, 2, 4 weeks to investigate the bone formation dynamic through fluorescence analysis. Ground sections were prepared from 8-week healing biopsies and histomorphometry was performed. RESULTS: The fluorescence evaluation of the early healing showed numerically better results for the nano-modified group; however this trend was not followed by the histomorphometric evaluation. A non-significant numerical superiority of the micro-rough group was observed in terms of vertical bone apposition, defect bone fill, bone-to-implant contact and bone density. In the intra-group analysis, the wider defects showed the worse results while the control sites showed the best results for the different parameters, but without statistical relevance. CONCLUSION: Both surfaces may lead to complete fill of circumferential defects, but the gap width has to be considered as a challenge. The nano-scale modification was beneficial in the early stages of bone healing, but the micro-rough surface showed numerical better outcomes at the 8-week final period.

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.

The influence of restorations and prosthetic crowns finishing lines on inflammatory levels after non-surgical periodontal therapy.

OBJECTIVE: The aim of the present study was to evaluate the inflammatory response in sites where crowns were placed supragingivally, at the level of the gingival margin and subgingivally. These were measured clinically and through the levels of interleukin-1 3 and matrix metalloproteinase-2, inflammatory mediators, before and after periodontal therapy. METHODS: From 68 patients analyzed, 10 were selected for this study. The gingival crevicular fluid of the patients was collected and analyzed using standard enzyme-linked immunosorbent assay (ELISA). The clinical parameters were measured and correlated with interleukin-1beta and matrix metalloproteinase-2. Both analyses were realized before (baseline) and 2 months after non-surgical periodontal therapy. The two-way variance analysis (two-way ANOVA), Tukey-Kramer multiple comparisons test (post hoc) and Pearson parametric correlation test were performed in statistical analysis. RESULTS: There were statistically significant differences before and after nonsurgical periodontal therapy when comparing supra- and subgingival margins for the plaque and bleeding indexes (p < 0.05). There was a tendency toward correlation between the reduction of plaque index and the reduction of interleukin-1beta levels, both for supragingival (r = 0.694, p = 0.026) and subgingival margins (r = 0.715, p = 0.020) post non-surgical periodontal therapy. The levels of matrix metalloproteinase-2 were not detectable by ELISA because they were below the detection threshold of the assay. CONCLUSION: Supragingival restorations appeared to be more adequate in promoting periodontal health when compared with the other possible marginal finish lines. They also presented a better response to basic periodontal treatment, according to clinical and inflammatory findings.

The effects of different loading times on the bone response around dental implants: a histomorphometric study in dogs.

PURPOSE: The aim of this study was to evaluate, through histomorphometric analysis, the effect that different loading times would have on the bone response around implants. MATERIALS AND METHODS: Three Replace Select implants were placed on each side of the mandible in eight dogs (n = 48 implants). One pair of implants was selected for an immediate loading protocol (IL). After 7 days, the second pair of implants received prostheses for an early loading protocol (EL). Fourteen days after implant placement, the third pair of implants received prostheses for advanced early loading (AEL). Following 12 weeks of prosthetics, counted following the positioning of the metallic crowns for the AEL group, the animals were sacrificed and the specimens were prepared for histomorphometric analysis. The differences between loading time in the following parameters were evaluated through analysis of variance: bone-to-implant contact, bone density, and crestal bone loss. RESULTS: The mean percentage of bone-to-implant contact for IL was 77.9% +/- 1.71%, for EL it was 79.25% +/- 2.11%, and for AEL it was 79.42% +/- 1.49%. The mean percentage of bone density for IL was 69.97% +/- 3.81%, for EL it was 69.23% +/- 5.68%, and for AEL it was 69.19% +/- 2.90%. Mean crestal bone loss was 1.57 +/- 0.22 mm for IL, 1.23 +/- 0.19 mm for EL, and 1.17 +/- 0.32 mm for AEL. There was no statistical difference for any of the parameters evaluated (P > .05). CONCLUSION: Different early loading times did not seem to significantly affect the bone response around dental implants.

Evaluation of in vitro human gingival fibroblast seeding on acellular dermal matrix.

The acellular dermal matrix (ADM) was introduced in periodontology as a substitute for the autogenous grafts, which became restricted because of the limited source of donor's tissue. The aim of this study was to investigate, in vitro, the distribution, proliferation and viability of human gingival fibroblasts seeded onto ADM. ADM was seeded with human gingival fibroblasts for up to 21 days. The following parameters were evaluated: cell distribution, proliferation and viability. Results revealed that, at day 7, fibroblasts were adherent and spread on ADM surface, and were unevenly distributed, forming a discontinuous single cell layer; at day 14, a confluent fibroblastic monolayer lining ADM surface was noticed. At day 21, the cell monolayer exhibited a reduction in cell density. At 7 days, about to 90% of adherent cells on ADM surface were cycling while at 14 and 21 days this proportion was significantly reduced. A high proportion of viable cell was detected on AMD surface both on 14 and 21 days. The results suggest that fibroblast seeding onto ADM for 14 days can allow good conditions for cell adhesion and spreading on the matrix; however, migration inside the matrix was limited.

Influence of implant surfaces on osseointegration.

The biological fixation between the dental implant surfaces and jaw bones should be considered a prerequisite for the long-term success of implant-supported prostheses. In this context, the implant surface modifications gained an important and decisive place in implant research over the last years. As the most investigated topic in, it aided the development of enhanced dental treatment modalities and the expansion of dental implant use. Nowadays, a large number of implant types with a great variety of surface properties and other features are commercially available and have to be treated with caution. Although surface modifications have been shown to enhance osseointegration at early implantation times, for example, the clinician should look for research evidence before selecting a dental implant for a specific use. This paper reviews the literature on dental implant surfaces by assessing in vitro and in vivo studies to show the current perspective of implant development. The review comprises quantitative and qualitative results on the analysis of bone-implant interface using micro and nano implant surface topographies. Furthermore, the perspective of incorporating biomimetic molecules (e.g.: peptides and bone morphogenetic proteins) to the implant surface and their effects on bone formation and remodeling around implants are discussed.