Carla Andreotti Damante

Clinical evaluation of the effects of low-intensity laser (GaAlAs) on wound healing after gingivoplasty in humans

Low-intensity laser therapy aims at pain suppression, edema reduction and acceleration of wound healing. The main goal of this study was to clinically evaluate the effects of Aluminum Gallium Arsenate laser - 670nm in wound healing after gingivoplasty in 11 patients. Surgery was performed in anterior superior and/or inferior regions. The right side of the patient (test group) received a laser energy density of 4J/cm², in a 48-hour interval, during one week, totalizing four sessions. The irradiation was punctual in a contact mode in three points. The left side did not receive irradiation (control group). Clinical evaluation was performed by five specialists in periodontology through photography of the treated areas at post-surgical periods of 7, 15, 21,30,60 days. The observers pointed the best healed side. The Sign test was used for statistical analysis with a confidence level of 5% (P<0.05). The examiners found a better pattern of healing sometimes in the test and sometimes in the control group until 21 days after surgery. After this period there was no apparent difference between them. There was no statistical difference between the sides (p>0.05). These results have shown that low-intensity laser therapy did not accelerate oral mucosa healing after gingivoplasty.

Long-term evaluation of periodontal parameters and implant outcomes in periodontally compromised patients: a systematic review.

BACKGROUND The aim of this systematic review is to evaluate the long-term outcomes of patients with periodontitis submitted to periodontal therapy/maintenance and implant placement. METHODS Studies reporting clinical and/or long-term implant outcomes from partially edentulous patients with periodontitis who were treated and followed periodontal maintenance for ≥5 years were considered eligible for the review. Screening of the articles, data extraction, and quality assessment were conducted independently and in duplicate. RESULTS Search of MEDLINE, EMBASE, and CENTRAL databases resulted in 959 papers, and of them 931 were excluded after title/abstract assessment. The full texts of 28 potentially eligible publications were screened, but only 10 studies met inclusion criteria. Most of the included studies (77.8%) presented a medium/high methodologic quality. The results demonstrated that patients with a diagnosis of periodontitis had satisfactory implant outcomes. Implant survival was high (92.1%) within studies reporting 10 years of follow-up. Parameters related to probing depth, clinical attachment level, and bone loss around teeth increased the occurrence of peri-implantitis and implant loss. Non-attendance to periodontal maintenance and smoking habits were also associated with less favorable implant outcomes. CONCLUSIONS This systematic review confirmed that implant therapy can be successfully used in patients with a diagnosis of periodontitis who underwent proper therapy and regular periodontal maintenance. Residual pockets, non-attendance to the periodontal maintenance program, and smoking were considered to be negative factors for the long-term implant outcomes.

Evaluation of tissue reaction to Aroeira (Myracrodruon urundeuva) extracts: a histologic and edemogenic study

Objectives This study evaluated subcutaneous tissue response to Aroeira (Myracrodruon urundeuva) extract employing edemogenic and histological analyses. Material and methods Test groups consisted of aqueous and ethanolic Aroeira extracts and saline (control). For edema quantification, 18 rats received an intravenous injection of Evans Blue. After 30 min, the extracts and saline were injected on the dorsum of the rats, which were then sacrificed after 3 and 6 h. Readings were performed in a spectrophotometer. For subcutaneous implantation, 30 rats received a polyethylene tube containing the extracts on their dorsum and then they were killed after 7 and 28 days. The samples were processed for histological analysis and evaluated with a light microscope. The inflammatory infiltrate was quantified. Results There were no statistically significant differences between aqueous extract and saline groups in relation to edema quantification in the different periods (p>0.05). Ethanolic solution resulted in more edema independently of the experimental period (p<0.05). Histological analysis showed similar results on the 7-day period for the 3 groups. There was a notable reduction on inflammatory cell number for saline and aqueous extract groups at 28 days. Conclusion The aqueous extract showed biocompatible properties similar to those of saline.

Demineralization of the Contacting Surfaces in Autologous Onlay Bone Grafts Improves Bone Formation and Bone Consolidation

BACKGROUND Autologous bone grafts are usually well consolidated after 4 to 5 months but can be incompletely interlocked with the native bone. This study investigated the effect of acid demineralization of the graft-bed interface on graft consolidation. METHODS Onlay bone grafts were performed on the calvaria of 36 guinea pigs. Half of the animals had the graft-bed contacting surfaces demineralized with 50% citric acid (pH 1.0) for 3 minutes (test group). The other half received no demineralization (control group). The bone grafts were immobilized by a resorbable membrane glued to the recipient bed with cyanoacrylate. After 7, 30, and 90 days, specimens (n = 6) were obtained for light microscopy. Data from qualitative analysis and computerized histomorphometry were statistically processed at a significance level of 5%. RESULTS Osteogenesis was not seen at the interface after 7 days. After 30 days, the test group showed 34.39% ± 13.4% of the interface area filled with mineralized tissue, compared to 17.14% ± 8.6% in the control group (P = 0.026). After 90 days, the mean percentages of mineralized tissue at the interface in the test and control specimens were 54.00% ± 11.23% and 38.65% ± 7.76% (P = 0.041), respectively. Within groups, a higher percentage of the area filled with mineralized tissue was seen at 90 days compared to 30 days (P = 0.004 for control and 0.041 for test). CONCLUSIONS Demineralization of the contacting surfaces between autologous bone graft and bone bed improved new bone formation and bone consolidation. These data need to be confirmed in humans.

Fluoride modulates preosteoblasts viability and matrix metalloproteinases-2 and -9 activities.

This study evaluated the influence of fluoride on cell viability and activity of matrix metalloproteinases (MMP) -2 and -9 secreted by preosteoblasts. Preosteoblasts (MC3T3-E1 murine cell line) were cultured in MEM medium supplement with 10% Fetal Bovine Serum (FBS) and nucleosides/ribonucleosides without ascorbic acid. Adherent cells were treated with different concentrations of F (as sodium fluoride-NaF) in medium (5 x 10(-6) M, 10(-5) M, 10(-4) M and 10(-3) M) for 24, 48, 72 and 96 h at 37ºC, 5% CO(2). Control cells were cultivated in MEM only. After each period, preosteoblast viability was assessed by MTT assay. MMP-2 and -9 activities were performed by gel zymography. Also, alkaline phosphatase (ALP) activity was quantified by colorimetry in all experimental groups. It was shown that cultured cells with the highest dose of F (10(-3) M) for 96 h decreased preosteoblast viability while lower doses of F did not alter it, when compared to untreated cells. No differences were observed in ALP activity among groups. Moreover, compared to control, the treatment of cells with F at low dose slightly increased MMP-2 and -9 activities after 24 h. It was concluded that F modulates preosteoblast viability in a dose-dependent manner and also may regulate extracellular matrix remodeling.

Bone demineralization with citric acid enhances adhesion and spreading of preosteoblasts.

BACKGROUND Previous studies have demonstrated that bone demineralization can improve consolidation in bone grafts. The biologic mechanisms underlying this phenomenon remain unclear. METHODS Twelve adult male guinea pigs were used in this experiment. Forty-five bone samples removed from the calvaria of nine animals were divided in groups (n = 9) according to the time of demineralization with citric acid (50%, pH 1): 15, 30, 90, and 180 seconds and non-demineralized samples (control). Preosteoblasts (MC3T3-E1) were cultured on the bone samples for 24, 48, and 72 hours (n = 3). Fifteen samples removed from the remaining three animals were analyzed by scanning electron microscopy/energy dispersive spectrometry (SEM/EDS) after demineralization (n = 3). RESULTS The number of preosteoblasts increased significantly with time in all groups. The bone surface area covered by these cells increased with time, except in the control group. Intragroup differences occurred between 24 and 72 hours (P < 0.05). Samples demineralized for 30 seconds showed greater area covered by preosteoblast cells than for the other times of demineralization in all periods of cell culture (P < 0.05) without a statistically significant difference compared with 15 seconds. SEM/EDS showed diminished content of calcium (Ca) after 15 seconds of demineralization, but the Ca content increased after 180 seconds of demineralization (P < 0.05). The phosphorus (P) amount increased significantly only after 30 seconds of demineralization (P < 0.5). The sulfur (S) content was increased in demineralized samples in relation to non-demineralized ones, reaching the highest level after 90 seconds, when the difference became significant in relation to all the other times of demineralization (P < 0.05). Magnesium (Mg) content did not differ significantly between demineralized and non-demineralized samples. CONCLUSIONS Bone surfaces demineralized for 30 seconds increased the spreading of preosteoblasts as well as the surface area covered by these cells. Bone demineralization deserves to be studied in periodontal and maxillofacial regenerative procedures.

Mouth floor enlargements related to the sublingual glands in edentulous or partially edentulous patients: a microscopic study

Mouth floor enlargements (MFE) are observed in edentulous and partially edentulous patients, impairing denture fitting, and have recently been described in the literature as hyperplasias of the sublingual glands. Objective: This study aims at describing the microscopic aspects of MFE that contribute to their final diagnosis. Methods: Twenty-four specimens were surgically removed from the enlarged mouth floor of 19 patients (15 females and 4 males). Patient age ranged from 48 to 74 years, with a mean of 57 years. The main surgical indication was to permit or improve the fitting of dentures. Six patients were completely edentulous and 13 were partially edentulous. The material was processed for microscopic examination and stained with hematoxylin-eosin, Mallorys trichrome and periodic-acid Schiff (PAS). Results and Conclusions: The epithelium of the mouth floor was normal in 17 cases, hyperplastic in 4 and atrophic in 3. Six of the 24 sublingual glands removed were microscopically normal, while the other specimens presented acinar atrophy with hyperplasia of duct-like structures. Interstitial fibrosis was observed in 18 cases and was accompanied by adipose tissue infiltration in 15. Decreased lymphoid tissue was observed in 16 samples and oncocytosis was present in 5 cases. We suggest that MFE in edentulous or partially edentulous patients should be considered as an entity for the text books.

Prevention and Periodontal Treatment in Down Syndrome Patients: A Systematic Review.

The aim of this systematic literature review was to evaluate which type of periodontal preventive and therapeutic approaches presents superior outcomes in patients with Down syndrome (DS). Studies reporting different methods of periodontal care from DS patients were considered eligible. Included clinical studies should indicate at least two periodontal parameters in different periods of assessment. Screening of the articles, data extraction and quality assessment were conducted independently and in duplicate. Electronic search according to the PICO search, with both Key-words and MESH terms were conducted in MEDLINE, EMBASE and CENTRAL databases until March 2016. Manual search was conducted in four journals, namely Journal of Periodontology, Journal of Clinical Periodontology, Journal of Periodontal Research and Special Care in Dentistry and their electronic databases were searched. Electronic and manual search resulted in 763 papers, and of them 744 were excluded after title/abstract assessment. The full text of 19 potentially eligible publications was screened and 9 studies met inclusion criteria. The results demonstrated the importance to introduce youngest DS patients in preventive programs, as well as participation of parents, caregivers or institutional attendants in supervising/performing oral hygiene. In studies with higher frequency of attendance, all age groups presented superior preventive and therapeutic results, irrespective of the therapeutic approach used (surgical/nonsurgical/periodontal care program). The important factors for reducing periodontal parameters were the frequency of the appointments and association with chlorhexidine/plaque disclosing agents as adjuvant treatment. This systematic review demonstrated that early introduction in periodontal care, participation of parents/caregivers/institutional attendants, frequency of attendance and association with chemical adjuvants (independently of the periodontal treatment adopted) seems to improve periodontal outcomes in preventive and periodontal treatment of DS patients. Registration number (Prospero): CRD42016038433.

Experimental Calcium Silicate-Based Cement with and without Zirconium Oxide Modulates Fibroblasts Viability

The aim of this study was to verify whether the use of zirconium oxide as a radiopacifier of an experimental calcium silicate-based cement (WPCZO) leads to cytotoxicity. Fibroblasts were treated with different concentrations (10 mg/mL, 1 mg/mL, and 0.1 mg/mL) of the cements diluted in Dulbeccos modified Eagles medium (DMEM) for periods of 12, 24, and 48 h. Groups tested were white Portland cement (WPC), white Portland cement with zirconium oxide (WPCZO), and white mineral trioxide aggregate Angelus (MTA). Control group cells were not treated. The cytotoxicity was evaluated through mitochondrial-activity (MTT) and cell-density (crystal violet) assays. All cements showed low cytotoxicity. In general, at the concentration of 10 mg/mL there was an increase in viability of those groups treated with WPC and WPCZO when compared to the control group (p<0.05). A similar profile for the absorbance values was noted among the groups: 10 mg/mL presented an increase in viability compared to the control group. On the other hand, smaller concentrations presented a similar or lower viability compared to the control group, in general. A new dental material composed of calcium silicate-based cement with 20% zirconium oxide as the radiopacifier showed low cytotoxicity as a promising material to be exploited for root-end filling.

In vitro evaluation of adhesion/proliferation of human gingival fibroblasts on demineralized root surfaces by toluidine blue O in antimicrobial photodynamic therapy

BACKGROUND Antimicrobial photodynamic therapy (aPDT) in Dentistry has important effects as bacterial destruction in areas with periodontal disease. Some dyes applied in aPDT could present low pH and, consequently, result in tooth demineralization. This study evaluated demineralization produced by aPDT with toluidine blue O (TBO) at low pH and analyzed adhesion/proliferation of human gingival fibroblasts (HGF). METHODS In the 1st phase, bovine enamel and root dentin fragments received 2 treatments: PDT4 group (TBO-100 μg/ml-pH 4-60s) plus laser (660 nm, 45 J/cm(2), 1.08 J, 30 mW, 30 s, spot 0.024 cm(2), 1.25 W/cm(2), sweeping, non-contact) and CA group (citric acid plus tetracycline-pH 1-180 s). Surface hardness loss and tooth wear were statistically analyzed (Students t test, ANOVA/Tukey, p<0.05). In the 2nd phase, human dentin fragments were divided in C (control group-scaling and root planing), PDT4 and CA. HGF (10(4), 5th passage) were cultured on these fragments for 24, 48 and 72 h and counted in scanning electron microscopy photographs. Number of HGF was analyzed using repeated-measures ANOVA and Tukey (p<0.05). RESULTS Percentage of surface hardness loss was similar in dentin for PDT4 (71.5%) and CA (76.1%) (p>0.05) and higher in enamel for CA (68.0%) compared to PDT4 (34.1%) (p<0.05). In respect to wear, no difference was found between PDT4 (dentin: 12.58 μm, enamel: 12.19 μm respectively) and CA (dentin: 11.74 μm and enamel: 11.03 μm) (p>0.05). Number of HGF was higher after 72 h in CA group (2.66, p<0.05) compared to PDT4 (2.2) and C (1.33). CONCLUSION PDT4 is not as aggressive as CA for enamel. However, dentin demineralized promoted by PDT4 does not stimulate HGF adhesion and proliferation as CA.