Resumo em Inglês:

Abstract Studies to assess the effects of therapies on pain and masticatory muscle function are scarce. Objective To investigate the short-term effect of transcutaneous electrical nerve stimulation (TENS) by examining pain intensity, pressure pain threshold (PPT) and electromyography (EMG) activity in patients with temporomandibular disorder (TMD). Material and Methods Forty patients with myofascial TMD were enrolled in this randomized placebo-controlled trial and were divided into two groups: active (n=20) and placebo (n=20) TENS. Outcome variables assessed at baseline (T0), immediately after (T2) and 48 hours after treatment (T1) were: pain intensity with the aid of a visual analogue scale (VAS); PPT of masticatory and cervical structures; EMG activity during mandibular rest position (MR), maximal voluntary contraction (MVC) and habitual chewing (HC). Two-way ANOVA for repeated measures was applied to the data and the significance level was set at 5%. Results There was a decrease in the VAS values at T1 and T2 when compared with T0 values in the active TENS group (p<0.050). The PPT between-group differences were significant at T1 assessment of the anterior temporalis and sternocleidomastoid (SCM) and T2 for the masseter and the SCM (p<0.050). A significant EMG activity reduction of the masseter and anterior temporalis was presented in the active TENS during MR at T1 assessment when compared with T0 (p<0.050). The EMG activity of the anterior temporalis was significantly higher in the active TENS during MVC at T1 and T2 when compared with placebo (p<0.050). The EMG activity of the masseter and anterior temporalis muscle was significantly higher in the active TENS during HC at T1 when compared with placebo (p<0.050). Conclusions The short-term therapeutic effects of TENS are superior to those of the placebo, because of reported facial pain, deep pain sensitivity and masticatory muscle EMG activity improvement.

Resumo em Inglês:

Abstract Natural compounds capable of modulating the host response have received considerable attention, and herbal products are suggested as adjunctive agents in periodontal disease treatment. Objective This study aimed to demonstrate the effect of grape seed extract (GSE) on periodontitis. Material and Methods Ligature induced periodontitis was created in 40 rats and they were assigned to four equal groups. One group was fed laboratory diet (group A) while three groups received GSE additionally. Silk ligatures were placed around the cervical area of the mandibular first molars for four weeks to induce periodontitis. The GSE groups were reallocated regarding GSE consumption as: for two weeks before ligation (group B; totally eight weeks), from ligation to two weeks after removal of the ligature (group C; totally six weeks), and for two weeks from ligature removal (group D; totally two weeks). Sections were assessed histologically and immunohistochemically. Inflammatory cell number (ICN), connective tissue attachment level (CAL), osteoclast density (OD), IL-10 and TGF-β stainings in gingival epithelium (GE), connective tissue (GC), and periodontal ligament (PL) were used as the study parameters. Results Lower ICN, higher CAL, and lower OD were observed in the GSE groups (p<0.05). IL-10 was more intensive in the GSE groups and in the GEs (p<0.05). Group B showed the highest IL-10 for PL (p<0.05). TGF-ß was higher in the GEs of all groups (p<0.017). Conclusions The results suggest anti-inflammatory activities of GSE, but further investigations are needed for clarification of these activities.

Resumo em Inglês:

Abstract Periodontitis can contribute to the development of insulin resistance. Gestational diabetes is a risk factor for type 2 diabetes. Therefore, periodontitis, when associated with gestational diabetes, could increase the risk for the development of type 2 diabetes after pregnancy. Objective The aim of this study was to verify the incidence on the development of type 2 diabetes in women with previous gestational diabetes with and without periodontitis after a three-year time interval. Material and Methods Initial sample of this follow-up study consisted of 90 women diagnosed with gestational diabetes who underwent periodontal examination. After three years, 49 women were subjected to new periodontal examination and biological, behavioral, and social data of interest were collected. Additionally, the quantification of the C-reactive protein in blood samples was performed. Fasting glucose and glycated hemoglobin levels were requested. Saliva samples were collected for quantification of interleukin 6 and 10, tumor necrosis factor α, matrix metalloproteinase 2 and 9. Results The incidence of type 2 diabetes mellitus was 18.4% and of periodontitis was 10.2%. There was no significant difference in the incidence of type 2 diabetes mellitus among women with and without periodontitis. It was observed impact of C-reactive protein in the development of type 2 diabetes mellitus. However, it was not observed impact of periodontitis on the development of type 2 diabetes mellitus among women with previous gestational diabetes. Conclusions It was not observed impact of periodontitis on the development of type 2 diabetes among women with previous gestational diabetes. The impact of C-reactive protein in the development of type 2 diabetes mellitus highlights the importance of an inflammatory process in the diabetes pathogenesis.

Resumo em Inglês:

Abstract Alternative photoinitiators with different absorption wavelengths have been used in resin composites (RCs), so it is crucial to evaluate the effectiveness of light-curing units (LCUs) on these products. Objective Using Fourier transform infrared analysis (FTIR) in vitro, the effects of varying radiant exposure (RE) values generated by second and third generation LED LCUs on the degree of conversion (DC) and maximum rate of polymerization (Rpmax) of an experimental Lucirin TPO-based RC were evaluated. Material and Methods 1 mm or 2 mm thick silicon molds were positioned on a horizontal attenuated total reflectance (ATR) unit attached to an infrared spectroscope. The RC was inserted into the molds and exposed to varying REs (18, 36 and 56 J/cm2) using second (Radii Plus, SDI) and third generation LED LCUs (Bluephase G2/Ivoclar Vivadent) or a quartz tungsten based LCU (Optilux 501/SDS Kerr). FTIR spectra (n=7) were recorded for 10 min (1 spectrum/s, 16 scans/spectrum, resolution 4 cm-1) immediately after their application to the ATR. The DC was calculated using standard techniques for observing changes in aliphatic to aromatic peak ratios both prior to, and 10 min after curing, as well as during each 1 second interval. DC and Rpmax data were analyzed using 3-way ANOVA and Tukey’s post-hoc test (p=0.05). Results No significant difference in DC or Rpmax was observed between the 1 mm or 2 mm thick specimens when RE values were delivered by Optilux 501 or when the 1 mm thick composites were exposed to light emitted by Bluephase G2, which in turn promoted a lower DC when 18 J/cm2 (13 s) were delivered to the 2 mm thick specimens. Radii Plus promoted DC and Rpmax values close to zero under most conditions, while the delivery of 56 J/cm2 (40 s) resulted in low DC values. Conclusions The third generation LCU provided an optimal polymerization of Lucirin TPO-based RC under most tested conditions, whereas the second generation LED-curing unit was useless regardless of the RE.

Resumo em Inglês:

Abstract Saliva when compared to blood collection has the following advantages: it requires no specialized personnel for collection, allows for remote collection by the patient, is painless, well accepted by participants, has decreased risks of disease transmission, does not clot, can be frozen before DNA extraction and possibly has a longer storage time. Objective and Material and Methods This study aimed to compare the quantity and quality of human DNA extracted from saliva that was fresh or frozen for three, six and twelve months using five different DNA extraction protocols: protocol 1 – Oragene™ commercial kit, protocol 2 – QIAamp DNA mini kit, protocol 3 – DNA extraction using ammonium acetate, protocol 4 – Instagene™ Matrix and protocol 5 – Instagene™ Matrix diluted 1:1 using proteinase K and 1% SDS. Briefly, DNA was analyzed using spectrophotometry, electrophoresis and PCR. Results Results indicated that time spent in storage typically decreased the DNA quantity with the exception of protocol 1. The purity of DNA was generally not affected by storage times for the commercial based protocols, while the purity of the DNA samples extracted by the noncommercial protocols typically decreased when the saliva was stored longer. Only protocol 1 consistently extracted unfragmented DNA samples. In general, DNA samples extracted through protocols 1, 2, 3 and 4, regardless of storage time, were amplified by human specific primers whereas protocol 5 produced almost no samples that were able to be amplified by human specific primers. Depending on the protocol used, it was possible to extract DNA in high quantities and of good quality using whole saliva, and furthermore, for the purposes of DNA extraction, saliva can be reliably stored for relatively long time periods. Conclusions In summary, a complicated picture emerges when taking into account the extracted DNA’s quantity, purity and quality; depending on a given researchers needs, one protocol’s particular strengths and costs might be the deciding factor for its employment.

Resumo em Inglês:

Abstract Reports have indicated that serotonin plays an important role in cell migration and differentiation during the organogenesis of several tissues, including the oral types. Administration of selective serotonin reuptake inhibitor (SSRI) drugs during pregnancy could affect the delivery of serotonin to embryonic tissues altering its development. Objective This study aimed to assess the effects of fluoxetine, a selective serotonin reuptake inhibitor, on the formation of the periodontal ligament during pregnancy and lactation in rat pups. Material and Methods Twelve pregnant rats of Wistar lineage were divided into four study groups. In the control group, 0.9% sodium chloride solution was administered orally, throughout the entire period of the 21 days of pregnancy (CG group) and in the CGL group, it was administrated during pregnancy and lactation (from day 1 of pregnancy to the 21st day after birth). Fluoxetine was administered orally at the dose of 20 mg/kg in a group treated during pregnancy only (FG group), and during pregnancy and lactation (FGL group). Histometrical, histochemical and immunohistochemical analysis of the maxillary first molar periodontium region of the 24 rat pups was made under light microscopy, and periodontal ligament collagen was qualitatively evaluated under a polarizing light microscope. Results The quantity of fibroblasts (p=0.006), osteoblasts (p=0.027) and cementoblasts (p=0.001) was reduced in pups from the rats that received fluoxetine during pregnancy and lactation. No alterations were seen in the collagen fibers. Conclusion These findings suggest that periodontal tissue may be sensitive to fluoxetine, and its interference in reducing periodontal cells depends on exposure time during lactation.

Resumo em Inglês:

Abstract Objective The objective of this study was to evaluate the local effects of statins as adjuvants for treatment by scaling and root planing (SRP) of periodontal disease induced in rats. Material and Methods Ninety rats were used in the present experiment. Periodontal disease was induced in all animals using a cotton thread placed in the left first mandibular molar. After 7 days of induction, the bandage was removed and the animals were divided into three groups: 1) NT group (n=30), no treatment; 2) SRP group (n=30): SRP and irrigation with control gel; 3) S group (n=30) - SRP and irrigation with Simvastatin. Ten animals from each group were euthanized at 7, 15 and 30 days after treatment. Gingival biopsy specimens were processed to analyze the expression of matrix metalloproteinase 8 (MMP-8). The mandibles were removed and submitted to radiographic and laboratory processing for histometric analysis. Results The S group showed a significantly lower expression of MMP-8 compared to NT and SRP groups in all experimental periods. In the radiographic and histometric analyses between the groups, S group showed a significantly lower bone loss (BL) compared to NT and SRP groups in all experimental periods. Conclusions Within the limits of this study, it can be concluded that locally applied statin was effective as an adjuvant treatment for SRP in rats with induced periodontal disease.

Resumo em Inglês:

Abstract Objective To prepare nanocomposite cements based on the incorporation of bioactive glass nanoparticles (nBGs) into BiodentineTM (BD, Septodent, Saint-Maur-des-Fosses Cedex, France) and to assess their bioactive properties. Material and Methods nBGs were synthesised by the sol-gel method. BD nanocomposites (nBG/BD) were prepared with 1 and 2% nBGs by weight; unmodified BD and GC Fuji IX (GIC, GC Corporation, Tokyo, Japan) were used as references. The in vitro ability of the materials to induce apatite formation was assessed in SBF by X-ray diffraction (XRD), attenuated total reflectance with Fourier transform infrared spectroscopy (ATR-FTIR), and scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis. BD and nBG/BD were also applied to dentine discs for seven days; the morphology and elemental composition of the dentine-cement interface were analysed using SEM-EDX. Results One and two percent nBG/BD composites accelerated apatite formation on the disc surface after short-term immersion in SBF. Apatite was detected on the nBG/BD nanocomposites after three days, compared with seven days for unmodified BD. No apatite formation was detected on the GIC surface. nBG/BD formed a wider interfacial area with dentine than BD, showing blockage of dentine tubules and Si incorporation, suggesting intratubular precipitation. Conclusions The incorporation of nBGs into BD improves its in vitro bioactivity, accelerating the formation of a crystalline apatite layer on its surface after immersion in SBF. Compared with unmodified BD, nBG/BD showed a wider interfacial area with greater Si incorporation and intratubular precipitation of deposits when immersed in SBF.

Resumo em Inglês:

Abstract Oral mucosa has been highlighted as a suitable source of epidermal cells due to its intrinsic characteristics such as its higher proliferation rate and its obtainability. Diabetic ulcers have a worldwide prevalence that is variable (1%-11%), meanwhile treatment of this has been proven ineffective. Tissue-engineered skin plays an important role in wound care focusing on strategies such autologous dermal-epidermal substitutes. Objective The aim of this study was to obtain autologous dermal-epidermal skin substitutes from oral mucosa from diabetic subjects as a first step towards a possible clinical application for cases of diabetic foot. Material and Methods Oral mucosa was obtained from diabetic and healthy subjects (n=20 per group). Epidermal cells were isolated and cultured using autologous fibrin to develop dermal-epidermal in vitro substitutes by the air-liquid technique with autologous human serum as a supplement media. Substitutes were immunocharacterized with collagen IV and cytokeratin 5-14 as specific markers. A Student´s t- test was performed to assess the differences between both groups. Results It was possible to isolate epidermal cells from the oral mucosa of diabetic and healthy subjects and develop autologous dermal-epidermal skin substitutes using autologous serum as a supplement. Differences in the expression of specific markers were observed and the cytokeratin 5-14 expression was lower in the diabetic substitutes, and the collagen IV expression was higher in the diabetic substitutes when compared with the healthy group, showing a significant difference. Conclusion Cells from oral mucosa could be an alternative and less invasive source for skin substitutes and wound healing. A difference in collagen production of diabetic cells suggests diabetic substitutes could improve diabetic wound healing. More research is needed to determine the crosstalk between components of these skin substitutes and damaged tissues.

Resumo em Inglês:

Abstract Decalcification of enamel during fixed orthodontic appliance treatment remains a problem. White spot lesions are observed in nearly 50% of patients undergoing orthodontic treatment. The use of fluoride-containing orthodontic materials has shown inconclusive results on their ability to reduce decalcification. The aims of this investigation were to compare the levels of Streptococcus mutans (SM) in saliva and biofilm adjacent to orthodontic brackets retained with a resin-modified glass ionomer cement (RMGIC) (Fuji ORTHO LC) and a light cured composite resin (Transbond XT), and to analyze the influence of topical application of the 1.23% acidulated phosphate fluoride (APF) on SM counts. In a parallel study design, two groups (n=14/15) were used with random allocation and high salivary SM counts before treatment. Biofilm was collected from areas adjacent to the brackets on teeth 13, 22, 33, and 41. Both saliva and biofilm were collected on the 7th, 21st, 35th, and 49th days after appliance placement. Topical fluoride application was carried out on the 35th day. Bonding with RMGIC did not alter SM counts in saliva or biofilm adjacent to the brackets. On the other hand, the biofilm adjacent to brackets retained with composite resin showed a significant increase in SM counts along the trial period. Topical application of 1.23% APF did not reduce salivary or biofilm SM counts regardless of the bonding material. In conclusion, fluoride topical application did not show efficacy in reducing SM. The use of RMGIC as bonding materials allowed a better control of SM cfu counts in dental biofilm hindering the significant increase of these microorganisms along the trial period, which was observed in the biofilm adjacent to the composite material.

Resumo em Inglês:

Abstract Objective This study evaluated the fracture resistance of endodontically treated teeth restored with fiber reinforced composite posts, using three resin composite core build-up materials, (Clearfil Photo Core (CPC), MultiCore Flow (MCF), and LuxaCore Z-Dual (LCZ)), and a nanohybrid composite, (Tetric N-Ceram (TNC)). Material and Methods Forty endodontically treated lower first premolars were restored with quartz fiber posts (D.T. Light-Post) cemented with resin cement (Panavia F2.0). Samples were randomly divided into four groups (n=10). Each group was built-up with one of the four core materials following its manufacturers’ instructions. The teeth were embedded in acrylic resin blocks. Nickel-Chromium crowns were fixed on the specimens with resin cement. The fracture resistance was determined using a universal testing machine with a crosshead speed of 1 mm/min at 1350 to the tooth axis until failure occurred. All core materials used in the study were subjected to test for the flexural modulus according to ISO 4049:2009. Results One-way ANOVA and Bonferroni multiple comparisons test indicated that the fracture resistance was higher in the groups with CPC and MCF, which presented no statistically significant difference (p>0.05), but was significantly higher than in those with LCZ and TNC (p<0.05). In terms of the flexural modulus, the ranking from the highest values of the materials was aligned with the same tendency of fracture loads. Conclusion Among the cores used in this study, the composite core with high filler content tended to enhance fracture thresholds of teeth restored with fiber posts more than others.

Resumo em Inglês:

Abstract Objective To explore the effects of hyaluronic acid (HA) on bleeding and associated outcomes after third molar extraction. Methods Forty patients who had undergone molar extraction were randomly divided into two groups; 0.8% (w/v) HA was applied to the HA group (n=20) whereas a control group (n=20) was not treated. Salivary and gingival tissue factor (TF) levels, bleeding time, maximum interincisal opening (MIO), pain scored on a visual analog scale (VAS), and the swelling extent were compared between the two groups. Results HA did not significantly affect gingival TF levels. Salivary TF levels increased significantly 1 week after HA application but not in the control group. Neither the VAS pain level nor MIO differed significantly between the two groups. The swelling extent on day 3 and the bleeding time were greater in the HA group than in the control group. Conclusions Local injection of HA at 0.8% prolonged the bleeding time, and increased hemorrhage and swelling in the early postoperative period after third molar extractions.

Resumo em Inglês:

Abstract Objective The aim of this study was to compare the prevalence of periodontal pathogens, systemic inflammatory mediators and lipid profiles in type 1 diabetes children (DM) with those observed in children without diabetes (NDM), both with gingivitis. Material and methods Twenty-four DM children and twenty-seven NDM controls were evaluated. The periodontal status, glycemic and lipid profiles were determined for both groups. Subgingival samples of periodontal sites were collected to determine the prevalence of periodontal microorganisms by PCR. Blood samples were collected for IL-1-β, TNF-α and IL-6 analysis using ELISA kits. Results Periodontal conditions of DM and NDM patients were similar, without statistical differences in periodontal indices. When considering patients with gingivitis, all lipid parameters evaluated were highest in the DM group; Capnocytophaga sputigena and Capnocytophaga ochracea were more prevalent in the periodontal sites of DM children. “Red complex” bacteria were detected in few sites of DM and NDM groups. Fusobacterium nucleatum and Campylobacter rectus were frequently found in both groups. Similar levels of IL-1-β, TNF-α and IL-6 were detected in DM and NDM children. Conclusion Clinical and immunological profiles are similar between DM and NDM children. The presence of Capnocytophaga sputigena and Capnocytophaga ochracea were associated with gingivitis in DM children.

Resumo em Inglês:

Abstract Objective To compare periapical radiograph (PR) and cone-beam computed tomography (CBCT) in the diagnosis of alveolar and root fractures. Material and Methods Sixty incisor teeth (20 higid and 40 with root fracture) from dogs were inserted in 60 anterior alveolar sockets (40 higid and 20 with alveolar fracture) of 15 macerated canine maxillae. Each fractured socket had a root fractured tooth inserted in it. Afterwards, each maxilla was submitted to PR in two different vertical angulation incidences, and to CBCT imaging with a small field of view (FOV) and high-definition protocol. Images were randomized and posteriorly analyzed by two oral and maxillofacial radiologists two times, with a two-week interval between observations. Results Sensitivity and specificity values were good for root fractures for PR and CBCT. For alveolar fractures, sensitivity ranged from 0.10 to 0.90 for PR and from 0.50 to 0.65 for CBCT. Specificity for alveolar fractures showed lower results than for root fractures for PR and CBCT. Areas under the ROC curve showed good results for both PR and CBCT for root fractures. However, results were fair for both PR and CBCT for alveolar fractures. When submitted to repeated measures ANOVA tests, there was a statistically significant difference between PR and CBCT for root fractures. Root fracture intraobserver agreement ranged from 0.90 to 0.93, and alveolar fracture intraobserver agreement ranged from 0.30 to 0.57. Interobserver agreement results were substantial for root fractures and poor/fair for alveolar fractures (0.11 for PR and 0.30 for CBCT). Conclusion Periapical radiograph with two different vertical angulations may be considered an accurate method to detect root fractures. However, PR showed poorer results than CBCT for the diagnosis of alveolar fractures. When no fractures are diagnosed in PR and the patient describes pain symptoms, the subsequent exam of choice is CBCT.

Resumo em Inglês:

Abstract Regenerative endodontic procedure (REP) has been proposed as a new approach to treat immature permanent teeth. However, materials used in REP for root canal disinfection or cervical sealing may induce tooth discoloration. Objectives To assess tooth crown’s color after intracanal treatment with triple antibiotic paste (TAP) or calcium hydroxide (CH); cervical sealing with glass ionomer cement (GIC) or mineral trioxide aggregate (MTA); and bleaching with carbamide peroxide. Material and Methods After pulp removal and color spectrophotometer measurement, 50 bovine incisors were divided into 4 experimental groups and one control (untreated). Experiments were performed in phases (Ph). Ph1: TAP (ciprofloxacin, metronidazole, minocycline), TAPM (ciprofloxacin, metronidazole, amoxicillin), DAP (ciprofloxacin, metronidazole), or CH treatment groups. After 1 and 3 days (d); 1, 2, 3 weeks (w); and 1, 2, 3 and 4 months (m), color was measured and medications were removed. Ph2: GIC or MTA cervical sealing, each using half of the specimens from each group. Color was assessed after 1d, 3d; 1w, 2w, 3w; 1m and 2m. Ph3: Two bleaching sessions, each followed by color measurement. Data were analyzed with ANOVA and post-hoc Holm-Sidak method. Results Ph1: Specimens of TAP group presented higher color alteration (ΔE) mean than those of TAPM group. No significant difference was found among TAP or TAPM and CH, DAP or Control groups. Ph2: cervical sealing materials showed no influence on color alteration. Ph3: Different ΔE means (from different groups), prior to bleaching, became equivalent after one bleaching session. Conclusions TAP induces higher color alteration than TAPM; color alteration increases over time; cervical sealing material has no influence on color alteration; and, dental bleaching was able to recover, at least partially, the tooth crown’s color.