Evaluation of Bone Response to a Nano HA Implant Surface on Sinus Lifting Procedures: Study in Rabbits.

The aim of this study was to evaluate the bone response to two different implant surfaces on sinus lift procedures in rabbits. Bilateral sinus lifting with inorganic bovine bone associated with collagen membrane and immediate implantation were performed in 16 rabbits. Custom mini-implants were randomly installed in the prepared sites: one side received a double acid-etched (DAE) surface and the other a nano-hydroxyapatite (NHA) surface. The animals were euthanized 30 and 60 days after surgery, and biopsies were collected for microtomographic and histomorphometric analysis. After 30 days, no intra- and inter-group statistical differences were observed in microtomographic analysis, while at 60 days, bone analysis showed statistically significant differences between groups (p < 0.05) for all the evaluated parameters. Histomorphometric analysis showed, after 30 days, mean % of Bone-to-Implant Contact (BIC) for DAE and NHA of 31.70 ± 10.42% vs. 40.60 ± 10.22% (p > 0.05), respectively; for % of Bone Area Fraction Occupancy (BAFO), mean values were 45.43 ± 3.597% for DAE and 57.04 ± 5.537% for NHA (p < 0.05). After 60 days, mean %BIC and %BAFO for DAE and NHA implants were statistically significant (p < 0.05). The NHA surface showed superior biological features compared to the DAE treatment, promoting higher bone formation around the implants in an experimental model of bone repair in a grafted area.

Root coverage with tunneling technique or modified advanced flap associated with acellular dermal matrix: results from 6 months randomized clinical trial.

OBJECTIVES: This study compared two surgical techniques using acellular dermal matrix (ADM) for the treatment of multiple gingival recessions. MATERIAL AND METHODS: Twenty patients, with bilateral RT1 gingival recessions, were selected. One side received a modified extended coronally advanced flap (MECAF), and the contralateral side a supra-periosteal flap (TUN). The evaluated parameters were probing depth (PD), relative clinical attachment level, gingival index, gingival recession height (GR), width of keratinized tissue, keratinized tissue thickness, and gingival recession area at baseline and 6 months postoperative. Pain was evaluated weekly, using a visual analog scale (VAS) during first month postoperative. RESULTS: Both groups were effective in reducing GR (ΔGR: MECAF 2.28 mm; TUN 1.93 mm), without significant differences. The % of root coverage was numerically superior favoring MECAF (MECAF 61.24%; TUN 56.07%), without significant differences between groups. VAS scale failed to provide differences between groups. CONCLUSIONS: Both treatment were effective in root coverage and might be valuable for the treatment of multiple gingival recessions. The use of vertical releasing incisions and a flap design including the papillae did not hamper root coverage. CLINICAL RELEVANCE: This study compared two techniques for use of ADM in large multiple gingival recessions. Within its limitations, both treatments successfully achieved root coverage and were able to reduce gingival recession. It is expected a partial root coverage when using these techniques in large gingival recessions. The study failed to provide significant differences between groups. The use of modified extended coronally advanced flap may be advisable for the treatment of multiple gingival recessions, specially involving large defects when using ADM, to avoid early matrix exposure.

Histological and Nanomechanical Properties of a New Nanometric Hydroxiapatite Implant Surface. An In Vivo Study in Diabetic Rats.

Implant therapy is a predictable treatment to replace missing teeth. However, the osseointegration process may be negatively influenced by systemic conditions, such as diabetes mellitus (DM). Microtopography and implant surface developments are strategies associated to better bone repair. This study aimed to evaluate, in healthy and diabetic rats, histomorphometric (bone to implant contact = %BIC; and bone area fraction occupancy = %BAFO) and nanomechanical (elastic modulus = EM; and hardness = H) bone parameters, in response to a nanometric hydroxyapatite implant surface. Mini implants (machined = MAC; double acid etched = DAE, and with addition of nano-hydroxyapatite = NANO) were installed in tibias of healthy and diabetic rats. The animals were euthanized at 7 and 30 days. NANO surface presented higher %BIC and %BAFO when compared to MAC and DAE (data evaluated as a function of implant surface). NANO surface presented higher %BIC and %BAFO, with statistically significant differences (data as a function of time and implant surface). NANO surface depicted higher EM and H values, when compared to machined and DAE surfaces (data as a function of time and implant surface). Nano-hydroxyapatite coated implants presented promising biomechanical results and could be an important tool to compensate impaired bone healing reported in diabetics.

Effect of smoking on the DNA methylation pattern of the SOCS1 promoter in epithelial cells from the saliva of patients with chronic periodontitis.

BACKGROUND: The aim of the present study was to evaluate the methylation pattern in the suppressor of cytokine signaling 1 (SOCS1) gene in smokers and non-smokers with chronic periodontitis (CP). METHODS: Methylation-specific polymerase chain reaction (PCR) was performed to determine the methylation status of the SOCS1 promoter in 45 saliva samples from smokers and non-smokers with CP. RESULTS: Cells from the saliva of CP patients who smoked were 7.08 times more likely to have a methylated SOCS1 promoter than cells from the saliva of non-smoking patients. CONCLUSIONS: SOCS1 gene promoter methylation, with its potential effects on the expression of this gene, seems to be a consequence of exposure to tobacco and not to periodontal disease. Further studies are needed to elucidate the relationship between the epigenetic control of immune response gene expression, exposure to environmental factors, and the development, progression, and prognosis of CP.

Sub-antimicrobial doses of doxycycline decreased bone loss related to ligature-induced periodontitis in hypertensive rats.

BACKGROUND/OBJECTIVE: The beneficial effects of sub-antimicrobial dose doxycycline (SDD) associated with nonsurgical periodontal therapy are well documented. Recently, the effects of SDD on metalloproteinases have been investigated in the treatment of hypertension. The aim of this study was to evaluate the effects of SDD on ligature-induced periodontitis in spontaneously hypertensive rats (SHR). METHODS: Fifty-four adult male rats were divided into three groups: SHR-C, SHR-L and SHR-L-DOX (C - Control; L - Ligature). In group SHR-L-DOX, animals were treated with daily 5 mg/kg SDD administration. In L groups, a ligature remained around mandibular first molars for the first 10 days. Each group was divided for euthanasia at 10 or 21 days. Microtomographic and histometric analyses were performed. Osteoclastogenesis was evaluated by tartrate-resistant acid phosphatase (TRAP) assay and gene expression of 84 inflammatory mediators by polymerase chain reaction (PCR) array. RESULTS: Group SHR-L-DOX presented reduced systolic blood pressure when compared with group SHR-L at both 10 and 21 days (p < 0.05). Group SHR-L-DOX showed decreased bone and attachment loss in comparison with group SHR-L at both 10 and 21 days (p < 0.05). SDD treatment reduced the amount of TRAP-positive cells at 10 days (p < 0.05). Group SHR-L-DOX showed a downregulated inflammatory genes profile in comparison with SHR-L at 10 and 21 days. CONCLUSION: SDD therapy exerted systemic modulatory effect on inflammation with reduced periodontal tissue destruction in hypertensive rats.

Multiple sessions of antimicrobial photodynamic therapy associated with surgical periodontal treatment in patients with chronic periodontitis.

BACKGROUND: This double-blind, randomized, controlled clinical trial assessed the efficacy of multiple sessions of antimicrobial photodynamic therapy (aPDT) as an adjunct to surgical periodontal treatment (ST) in patients with severe chronic periodontitis (SCP). METHODS: Sixteen patients with SCP were treated with aPDT+ST (test group, TG) or ST only (control group, CG), in a split-mouth design. aPDT was applied at 0, 2, 7, and 14 postoperative days only in TG. All patients were followed up for 90 days after surgery. The following clinical and microbiological parameters were assessed: clinical attachment level (CAL), probing depth (PD), gingival recession (GR), bleeding on probing (BOP), plaque index (PI), and count of 40 subgingival microbial species (checkerboard DNA-DNA hybridization). Data were collected at baseline (preintervention), at 60 days (30 days after the end of non-surgical therapy), and at 150 days (90 days after surgery). RESULTS: A significant reduction in PD was observed at 150 days for the TG, when compared with the CG (P Ë‚ 0.05). CAL gain was significantly higher in the TG at 60 and 150 days (P Ë‚ 0.05). Changes in the subgingival microbiota were similar between the groups (P Ëƒ 0.05), but the TG revealed a larger number of bacteria associated with periodontal disease at the end of the experiment compared with the CG (P < 0.05). CONCLUSION: Multiple sessions of aPDT as an adjunct to surgical periodontal treatment significantly improved clinical parameters at 90 postoperative days.

Effects of Bifidobacterium probiotic on the treatment of chronic periodontitis: A randomized clinical trial.

AIM: This randomized placebo-controlled clinical trial evaluated the effect of Bifidobacterium animalis subsp. lactis (B. lactis) HN019-containing probiotic lozenges as adjuvant to scaling and root planing (SRP) in patients with generalized chronic periodontitis. MATERIALS AND METHODS: Forty-one chronic periodontitis patients were recruited and monitored clinically, immunologically, and microbiologically at baseline (before SRP) and 30 and 90 days after SRP. All patients were randomly assigned to a Test (SRP + Probiotic, n = 20) or Control (SRP + Placebo, n = 21) group. The probiotic lozenges were used twice a day for 30 days. The data were statistically analysed. RESULTS: The Test group presented a decrease in probing pocket depth and a clinical attachment gain significantly higher than those of the Control group at 90 days. The Test group also demonstrated significantly fewer periodontal pathogens of red and orange complexes, as well as lower proinflammatory cytokine levels when compared to the Control group. Only the Test group showed an increase in the number of B. lactis HN019 DNA copies on subgingival biofilm at 30 and 90 days. CONCLUSION: The use of B. lactis HN019 as an adjunct to SRP promotes additional clinical, microbiological, and immunological benefits in the treatment of chronic periodontitis (NCT03408548).

Evaluation of a bone substitute covered with a collagen membrane for ridge preservation after tooth extraction. Clinical and tomographic randomized controlled study in humans.

OBJECTIVE: To evaluate the use of a synthetic bone substitute covered with a collagen membrane for ridge preservation after tooth extraction, by clinical and tomographic analysis. MATERIAL AND METHODS: Fifteen patients, presenting at least two maxillary anterior teeth indicated for extraction, were selected: in the test group (TG), post-extraction sockets were filled by a synthetic bone substitute; in the control group (CG), by blood clot. In both groups, the sockets were covered by a collagen membrane. Cone-beam computerized tomography (CBCT) scans were acquired immediately after and 6 months post-surgically, and horizontal and vertical dimensional bone changes were quantified. RESULTS: Transurgical clinical analysis presented no statistically significant differences between TG and CG (p > .05). CBCT intragroup evaluation presented statistically significant reduction for the buccal alveolar measurement (TG = 1.58 mm or 21.82%, and CG = 1.66 mm or 24.08%) and horizontal cervical measurement (TG = 0.55 mm or 8.30% and CG = 1.30 mm or 17.68%), and not significant for palatal alveolar measurement (TG = 0.44 mm or 3.42% and CG = 0.26 mm or 3.89%). For alveolar height and horizontal apical measurements, this decrease was significant only for the CG, with reductions of 1.03 mm and 0.50 mm, respectively, compared to a decrease of 0.57 mm and 0.19 mm for the TG. The intergroup analysis showed significant difference for cervical horizontal measurement after 6 months (p < .05). CONCLUSION: The results showed that the use of the bone substitute covered with a collagen membrane resulted in less changes in vertical and horizontal alveolar ridge dimensions than the collagen membrane alone.

Effect of surgical periodontal treatment associated to antimicrobial photodynamic therapy on chronic periodontitis: A randomized controlled clinical trial.

AIM: This randomized controlled clinical trial evaluated the effects of an adjunctive single application of antimicrobial photodynamic therapy (aPDT) in Surgical Periodontal Treatment (ST) in patients with severe chronic periodontitis (SCP). MATERIAL AND METHODS: In a split-mouth design, 20 patients with SCP were treated with aPDT+ST (Test Group, TG) or ST only (Control Group, CG). aPDT was applied in a single episode, using a diode laser and a phenothiazine photosensitizer. All patients were monitored until 90 days after surgical therapy. Levels of 40 subgingival species were measured by checkerboard DNA-DNA hybridization at baseline, 60 and 150 days. Clinical and microbiological parameters were evaluated. RESULTS: In deep periodontal pockets depth (PPD ≥5 mm), Test Group presented a significantly higher decrease in PPD than Control Group at 90 days after surgical therapy (p < .05). Test Group also demonstrated significantly less periodontal pathogens of red complex (Treponema denticola) (p < .05). CONCLUSION: A single episode of aPDT used in adjunct to open flap debridement of the root surface in the surgical treatment of SCP: i) significantly improved clinical periodontal parameters; ii) eliminates periodontal pathogens of the red complex more effectively (NCT02734784).

Bioactive Glass Particles in Two-Dimensional and Three-Dimensional Osteogenic Cell Cultures.

This study aimed to investigate the influence of a three-dimensional cell culture model and bioactive glass (BG) particles on the expression of osteoblastic phenotypes in rat calvaria osteogenic cells culture. Cells were seeded on two-dimensional (2D) and three-dimensional (3D) collagen with BG particles for up to 14 days. Cell viability and alkaline phosphatase (ALP) activity was performed. Cell morphology and immunolabeling of noncollagenous bone matrix proteins were assessed by epifluorescence and confocal microscopy. The expressions of osteogenic markers were analyzed using RT-PCR. Mineralized bone-like nodule formation was visualized by microscopy and calcium content was assessed quantitatively by alizarin red assay. Experimental cultures produced a growing cell viability rate up to 14 days. Although ALP activity at 7 days was higher on BG cultures, cells on 3D and 3D+BG had an activity decrease of ALP at 14 days. Three-dimensional conditions favored the immunolabeling for OPN and BSP and the expression of ALP and COL I mRNAs. BG particles influenced positively the OC and OPN mRNAs expression and calcified nodule formation in vitro. The results indicated that the 3D cultures and BG particles contribute to the expression of osteoblastic phenotype and to differentiated and mineralized matrix formation.

Benefits of Bifidobacterium animalis subsp. lactis Probiotic in Experimental Periodontitis.

BACKGROUND: This study evaluates effects of topical administration of probiotic bacteria of the genus Bifidobacterium on experimental periodontitis (EP) in rats. METHODS: Thirty-two rats were divided into groups C (control; without EP), EP (EP only), C-HN019 (control+probiotic), and EP-HN019 (EP+probiotic). On day 0 of the experiment, animals of groups EP and EP-HN019 received cotton ligatures around mandibular first molars (MFMs). In groups C-HN019 and EP-HN019, 1 mL of suspensions containing Bifidobacterium animalis subsp. lactis (B. lactis) HN019 was topically administered in the subgingival region of MFMs on days 0, 3, and 7. In groups C and EP, topical administrations were performed using a sham suspension (without probiotic). All animals were euthanized at day 14. Gingival tissue, hemimandibles, and oral biofilm were collected. Data were statistically analyzed (P <0.05). RESULTS: Group EP presented greater bone porosity, trabecular separation, and connective tissue attachment loss (CTAL) as well as reduced bone volume than all other groups (P <0.05). In group EP-HN019, there were greater proportions of Actinomyces and Streptococcus-like species and lower proportions of Veillonella parvula, Capnocytophaga sputigena, Eikenella corrodens, and Prevotella intermedia-like species than group EP. Group EP-HN019 presented greater expressions of osteoprotegerin and ß-defensins than group EP (P <0.05). Group EP presented greater levels of interleukin-1ß and receptor activator of nuclear factor-kappa B ligand than group EP-HN019 (P <0.05). CONCLUSION: Topical use of B. lactis HN019 promotes a protective effect against alveolar bone loss and CTALs attributable to EP in rats, modifying immunoinflammatory and microbiologic parameters.

Preliminary Results of Non-Surgical Periodontal Treatment in Patients With Breast Cancer Undergoing Chemotherapy.

BACKGROUND: Although priority is often given to treat the cancer itself, focus should also be directed to prevention and improvement of oral complications that may occur as a result of cancer and/or its treatment. This study compares periodontal treatment results in healthy patients and patients with breast cancer undergoing chemotherapy by monitoring clinical conditions and C-reactive-protein (CRP) levels. METHODS: Thirty-five participants were allocated to one of two groups: patients with periodontitis (P) (n = 18) and patients with breast cancer and periodontitis (CAN/P) (n = 17). The following clinical parameters were assessed at baseline and 45, 90, and 180 days after non-surgical periodontal treatment (NSPT): 1) probing depth (PD); 2) clinical attachment level (CAL); 3) plaque index (PI); 4) gingival index (GI); 5) CRP; and 6) complete blood count. Clinical parameters and CRP levels were statistically analyzed. RESULTS: P and CAN/P groups presented a statistically significant decrease in PD after NSPT at 45, 90, and 180 days compared with baseline (P <0.05). There was a CAL gain in the P group and a significant reduction in PI and GI at 45, 90, and 180 days for both groups (P <0.05). At 180 days after NSPT treatment, the CAN/P group showed a higher number of residual pockets (P <0.05) compared with the P group (46.48 ± 26.80 and 7.58 ± 7.40, respectively). The P group demonstrated a significant reduction in CRP levels at 45 and 180 days after NSPT compared with baseline (P <0.05), whereas this reduction was not observed in the CAN/P group. CONCLUSION: Patients with breast cancer who were undergoing chemotherapy responded to periodontal non-surgical therapy, although with less favorable results than patients with periodontitis without cancer, and may require additional or adjunctive periodontal treatments.

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).

Comparative study of two surgical techniques for root coverage of large recessions in heavy smokers.

Reduced root coverage due to diminished periodontal vascularity can be expected in heavy smokers. The aim of this study was to evaluate the root coverage obtained for large gingival recessions in heavy smokers using two different surgical techniques. Twenty heavy smokers were selected. Each patient had large, bilateral Miller class I or II gingival recessions (Control Group (CG): 3.30 ± 1.29; Test Group (TG): 3.45 ± 0.80) on nonmolar teeth. Clinical measurements of probing pocket depth (PPD), clinical attachment level (CAL), recession height (RH), keratinized mucosa height (KMH), and keratinized mucosa thickness (KMT) were determined at baseline and after 12 months. One side received a coronally positioned flap (CPF), while the contralateral side received the extended flap technique (EFT), both procedures carried out in conjunction with a subepithelial connective tissue graft (SCTG). Saliva samples to measure cotinine levels were taken at baseline and after 12 months as an indicator of the level of exposure to nicotine. Intergroup and intragroup analysis showed no statistical differences for the evaluated clinical parameters. Patients maintained the same exposure to smoke during the evaluation period. Both techniques resulted in low root coverage (CPF: 48.60%; EFT: 54.28%), but both techniques were effective in decreasing the gingival recessions (P ≤ 0.01). The variables smoke exposure, root coverage, and the thickness and height of keratinized tissue were subjected to linear regression. Regardless of the surgical technique used, heavy smoking strongly limits root coverage, especially for large recessions.

Influence of periodontal tissue thickness on buccal plate remodelling on immediate implants with xenograft.

AIM: To evaluate the influence of gingival thickness and bone grafting on buccal bone plate remodelling after immediate implant placement in sockets with thin buccal bone, using a flapless approach. MATERIALS AND METHODS: The gingiva of eight dogs was thinned at one side of the mandible, mandibular premolars were extracted without flaps, and four implants were installed on each side at 1.5 mm from the buccal bone. The sites were randomly assigned into: TG (test group) = thin gingiva; TG + GM (TG with grafting material); CG (control group) = normal gingiva; and CG + GM (CG with grafting material). After 12 weeks the dogs were sacrificed and the samples were processed for histological analysis. RESULTS: All animals exhibited a thin buccal bone initially. In all the experimental groups the buccal gap was filled with newly formed bone and the buccal bone level was slightly apical to the implant shoulder. There were no statistically significant differences among the groups for the histomorphometric parameters. CONCLUSIONS: The thickness of the buccal bone was a fundamental factor in buccal bone plate resorption, even with flapless implantation. The gingival thickness or the addition of a biomaterial in the gap did not influence the results.

Salivary, blood and plasma nitrite concentrations in periodontal patients and healthy individuals before and after periodontal treatment.

BACKGROUND: To date, no study has employed ozone-based reductive chemiluminescence to compare nitrite concentration in the saliva of periodontal disease (PD) and healthy individuals or in the various blood compartments of the same individuals before and after periodontal treatment. We evaluated nitrite concentrations in whole, submandibular, and parotid saliva, as well as in whole blood, erythrocytes, and plasma of healthy volunteers and patients with chronic periodontitis. METHODS: Data obtained for the PD and control groups were compared before and 3 months after periodontal therapy. RESULTS: At baseline, stimulated whole saliva nitrite concentration was lower in PD patients (mean=57.3 ± 9.8 µmol/L) as compared with healthy individuals (92.5 ± 13.6 µmol/L, P<0.05). PD and periodontal treatment did not affect submandibular or parotid saliva nitrite concentrations. PD patients presented higher baseline whole blood nitrite concentration (238.4 ± 45.7 µmol/L) as compared with values recorded 3 months after therapy (141.3 ± 20.1 nmol/L, P<0.05). PD patients' erythrocytes exhibited higher baseline nitrite concentration (573.1 ± 97.8 nmol/L) as compared with three months after therapy (298.7 ± 52.1 nmol/L, P<0.05). Again, PD and PD treatment did not impact plasma nitrite concentration. CONCLUSIONS: PD patients had lower nitrite concentration in whole saliva, and this situation remained unchanged after periodontal treatment. Nevertheless, erythrocytes and whole blood nitrite levels diminished after periodontal treatment.

A modified surgical flap for root coverage in association with grafting materials.

PURPOSE: To clinically evaluate in humans the effectiveness of a modified flap for root coverage associated with connective tissue graft or acellular dermal matrix graft after a postoperative period of 12 months. MATERIALS AND METHODS: Thirty bilateral gingival recessions were selected and randomly assigned into experimental groups. All of them were treated with a modified surgical flap, with the releasing incisions placed on the mesial and distal line angles of the adjacent teeth, distant from the main defect, providing a broader flap. One site was treated with the autograft and the contralateral site, with the allograft. Probing depth, clinical attachment level, gingival recession, and keratinized tissue width were measured at baseline and after 12 months. RESULTS: Both procedures significantly improved the clinical parameters evaluated, without statistically significant differences between them. While the autograft group had a mean gingival recession reduction from 3.15 to 0.67 mm, in the allograft group, it was from 3.47 to 0.93 mm. CONCLUSION: The extended flap technique can improve the root coverage results using the subepithelial connective tissue graft or the acellular dermal matrix. CLINICAL SIGNIFICANCE: Graft survival plays a decisive role in mucogingival therapy results and the selection of the appropriate surgical technique is important to achieve it. This 12-month randomized study showed that an extended flap is able to improve the results of root coverage of localized gingival recessions not only when using the acellular dermal matrix as shown in a previous study, but also when using the subepithelial connective tissue. On this basis, this surgical technique can be suggested as the procedure of choice for treating this type of defect.

Antimicrobial photodynamic therapy as an adjunct to non-surgical treatment of aggressive periodontitis: a split-mouth randomized controlled trial.

BACKGROUND: The management of aggressive periodontitis (AgP) represents a challenge for clinicians because there are no standardized protocols for an efficient control of the disease. This randomized controlled clinical trial evaluated the effects of repeated applications of antimicrobial photodynamic therapy (aPDT) adjunctive to scaling and root planing (SRP) in patients with AgP. METHODS: Using a split-mouth design, 20 patients with generalized AgP were treated with aPDT + SRP (test group) or SRP only (control group). aPDT was applied at four periods. All patients were monitored for 90 days. Clinical, microbiologic, and immunologic parameters were statistically analyzed. RESULTS: In deep periodontal pocket analysis (probing depth [PD] ≥ 7 mm at baseline), the test group presented a decrease in PD and a clinical attachment gain significantly higher than the control group at 90 days (P < 0.05). The test group also demonstrated significantly less periodontal pathogens of red and orange complexes and a lower interleukin-1ß/interleukin-10 ratio than the control group (P < 0.05). CONCLUSION: The application of four sessions of aPDT, adjunctive to SRP, promotes additional clinical, microbiologic, and immunologic benefits in the treatment of deep periodontal pockets in single-rooted teeth in patients with AgP.

Bone Formation in a Local Defect around Dental Implants Coated with Extracellular Matrix Components.

PURPOSE: The coating of implant surfaces with components of the extracellular matrix offers an approach to influence peri-implant bone healing. In this study, bone healing around coated implants is analyzed in a peri-implant defect model. MATERIALS AND METHODS: Eight months after extraction of the premolar teeth, six dogs received 48 implants (eight per animal) in the mandible. Implant surfaces were sandblasted and acid-etched, and some were additionally coated with collagen type II and chondroitin sulfate (collagen/CS). On each side of the mandible, implants either had no peri-implant defect (control side) or a vertical defect of 5 mm in depth and 0.5, 1.0, or 2.0 mm in width. Implants healed submerged for 8 weeks. Fluorochrome staining, histology, and histomorphometry were used to analyze implant osseointegration. RESULTS: Fluorochrome labels showed an increased mineralization around collagen/CS-coated surfaces at 4 weeks (p = .031). Histomorphometry generally showed lower vertical and horizontal bone apposition with increasing gap size for both surface types. In gapless sites and 0.5-mm gaps, collagen/CS coated implants showed increased bone volume in areas directly adjacent to the implant, in comparison with uncoated implants (p < .05). CONCLUSION: The width of the peri-implant gap influences peri-implant bone formation. Complete filling of all gaps by newly formed bone could not be observed around either surface. In proximity to the surface, implant surface coating by collagen/CS positively influenced bone formation.

The influence of the periodontal biotype on peri-implant tissues around immediate implants with and without xenografts. Clinical and micro-computerized tomographic study in small Beagle dogs.

OBJECTIVE: Soft tissues and buccal bone plate remodeling after immediate implantation in sockets with thin buccal bone, using the flapless approach with or without bone graft into the buccal gap, was compared between sites with thin and normal gingiva. MATERIAL AND METHODS: Eight dogs had the gingiva of one side of the mandible thinned, the mandibular premolars were extracted without flaps, and 4 implants were installed in each side, positioned 1.5 mm from the buccal bone. The sites were randomly assigned into: TG (test group) = thin gingiva; TG + GM (TG with grafting material); CG (control group) = normal gingiva; and CG + GM (CG with grafting material). Buccal bone thickness (BBT), thickness of keratinized tissue (TKT), alveolar thickness (AT), gingival recession (GR), and probing depth (PD) were clinically evaluated. Within 12 weeks the dogs were sacrificed and the samples were analyzed by micro-computerized tomography. RESULTS: A thin BBT was observed in all the dogs. The presurgical procedures reduced TKT in the test group, with minimal changes of the AT. There were no statistically significant differences among the groups for the clinical parameters and the tomographic analysis showed similar linear and tri-dimensional bone reduction in all the groups. CONCLUSION: The thickness of the buccal bone was a fundamental factor in buccal bone plate resorption, even with flapless implantation. The decrease in gingival thickness or the addition of a biomaterial in the gap did not influence the results.