To evaluate the effect of a fluoride toothpaste containing nano-sized sodium hexametaphosphate (HMPnano) on enamel demineralization on the biochemical composition and insoluble extracellular polysaccharide (EPS) in biofilm formed in situ.
MethodsThis crossover double-blind study consisted of four phases (7 days each), in which 12 volunteers wore intraoral appliances containing four enamel bovine blocks. The cariogenic challenge was performed using 30% sucrose solution (6×/day). Blocks were treated 3×/day with the following toothpastes: no F/HMP/HMPnano (Placebo), conventional fluoride toothpaste, 1100 ppm F (1100F), 1100F + 0.5% micrometric HMP (1100F/HMP), and 1100F + 0.5% nano-sized HMP (1100F/HMPnano). The percentage of surface hardness loss (%SH), integrated loss of subsurface hardness (ΔKHN), and enamel calcium (Ca), phosphorus (P), and fluoride (F) were determined. Moreover, biofilms formed on the blocks were analyzed for F, Ca, P, and insoluble extracellular polysaccharide (EPS) concentrations. Data were analyzed using one-way ANOVA, followed by Student–Newman–Keuls’ test (p < 0.001).
Results1100F/HMPnano promoted the lowest %SH and ΔKHN among all groups (p < 0.001). The addition of HMPnano to 1100F significantly increased Ca concentrations (p < 0.001). The 1100F/HMPnano promoted lower values of EPS when compared with 1100F (~ 70%) (p < 0.001) and higher values of fluoride and calcium in the biofilms (p < 0.001).
Conclusion1100F/HMPnano demonstrated a greater protective effect against enamel demineralization and on the composition of biofilm in situ when compared to 1100F toothpaste.
Clinical relevanceThis toothpaste could be a viable alternative to patients at high risk of caries.
相似文献This ex vivo study was performed to investigate the effect of radiotherapy (RT) delivery time on fracture resistance of mandibular premolars filled with Biodentine or gutta-percha/sealer (GPS).
Materials and methodsSeventy-two mandibular premolars were used in this study. Randomly selected 24 teeth were kept intact for the control groups (with and without irradiation). Then, the remaining 48 teeth were randomly assigned into 4 groups (n = 12) according to RT delivery time (irradiated before or after root canal treatment) and obturation materials as follows: Group RT + GPS, Group: GPS + RT, Group RT + Biodentine and Group Biodentine + RT. The samples were either initially endodontically treated and then irradiated or initially irradiated and then endodontically treated with one of the abovementioned materials. The samples were irradiated at 2 Gy per fraction, 5 times a week for a total dose of 60 Gy in 30 fractions over 6 weeks. The roots were embedded in self-polymerizing acrylic resin. The fracture resistance was evaluated in a universal testing machine. Data was analyzed by one-way ANOVA and Games-Howell post hoc test at p < 0.05.
ResultsRadiation therapy significantly reduced fracture resistance of intact teeth (p < 0.05). The highest fracture resistance was observed in intact/non-irradiated teeth and the lowest fracture resistance in Biodentine + RT group (p < 0.05). The effect of RT delivery time was insignificant when GPS was preferred as the root canal filling material (p > 0.05); it was significant when preferring Biodentine (p < 0.05). When RT was applied to the teeth after Biodentine obturation, the fracture resistance decreased significantly compared to the teeth that were obturated with GPS after or before RT application (p < 0.05).
ConclusionBoth RT time and obturation materials (Biodentine or gutta-percha/sealer) affect the fracture resistance of the endodontically treated teeth.
Clinical relevanceEndodontic treatment could be completed with both materials after RT; however, when the endodontic treatment was initially completed and the teeth were subsequently exposed to RT, it was shown that the reinforcement effect of Biodentine decreased.
相似文献This study aims to compare the degree of conversion of two different curing protocols used during adhesive cementation. The following resin luting agents were tested: Hri Flow (MF) and pre-heated Hri Micerium (MH); light-cure Nexus Third Generation (NX3L) and dual-cure Nexus Third Generation (NX3D); dual cured RelyX Ultimate (RXU) and light-cure RelyX Veneers (RXL). For each tested material, ten samples were prepared and divided into two groups which had different curing protocols (P1 and P2): in P1, samples were cured for 40 s; in P2, samples were cured for 5 s, and then, after 20 s, cured again for additional 40 s. The degree of conversion (DC) was evaluated both during the first 5 min of the curing phase and after 1, 2, 7, 14 and 28 days (p = 0.05). Different trends were observed in DC values after 5 min by comparing P1 and P2. In both P1 and P2, DC decreased as follows, MH > MF > NX3L > RXL > RXU > NX3D. There were significant differences of DC values among all resin luting agents (p < 0.05) in P1, while no significant differences existed between MH and MF, and NX3L and RXL in P2. At 1, 2, 7, 14 and 28 days the light curing luting agents had a higher DC than the dual luting agents (p < 0.05). P1 and P2 were not statistically different at each time point (p > 0.05). Both P1 and P2 protocols let achieve an acceptable DC after 28 days. The tested P2 can be safely used to lute indirect restorations, simplifying the removal of cement excesses.
相似文献This study aimed to evaluate the effects of chronic consumption of cachaça, a Brazilian beverage containing alcohol, on submandibular glands (SM) of rats by using histomorphometric and biochemical parameters.
Materials and methodsTwenty-four male rats (40 days of age) were assigned into the following four groups (n = 6): two control groups for 75 days (C75) and 105 days (C105), and two experimental groups of cachaça ingestion with ascending concentrations for consecutive 75 days (CA75) and 105 days (CA105). On the right SM glands, the striated, granular and acini ducts were processed for histomorphometric analysis. The left SM glands were weighed and stored at − 80 °C, to evaluate through biochemical tests carried out by spectrophotometric methods, the functional activity of total acid phosphatase (TAP), tartrate-resistant acid phosphatase (TRAP), and alkaline phosphatase (ALP) and to determine the mucin levels.
ResultsThe absolute and relative weights of the SM glands in both experimental groups were reduced in relation to the controls (p < 0.05). The histomorphometric analysis showed a significant reduction of the acini area (p < 0.05) and non-relevant reduction of striated ducts (p > 0.05). The granular ducts did not show a significant increase of the area (p > 0.05). The TAP and TRAP activities were significantly decreased in the experimental groups (p < 0.05), while the ALP functional activity decreased moderately (p > 0.05). Mucin levels also had a significant reduction when compared with the control groups (p < 0.05).
ConclusionsChronic consumption of cachaça can cause morphological changes associated with glandular atrophy, loss of biochemical functionality of phosphatases, and the reduction of mucin synthesis.
Clinical relevanceThe consumption of cachaça can compromise the functions of the submandibular glands by altering their morphology and enzymatic activity.
相似文献To assess the remineralization capacity of carious, non-carious, and combined white spot lesions (WSLs) using the ICDAS and SS-OCT.
Materials and methodsThis clinical trial was based on a quasi-experimental design. Forty-two healthy subjects (median age 26.6 years), who visited university hospital and had at least one WSL with an ICDAS score of 2 or 1, were recruited. The subjects chewed a non-blind sugar-free gum containing bioavailable calcium and fluoride for 3 months. The remineralization capacities of carious and non-carious 121 WSLs were assessed using ICDAS by two calibrated non-blind examiners and optical boundary depth (BD) by SS-OCT at a monthly recall. The outcome variables, transitions of ICDAS score, mean BD, and mean BD recovery rate (RR%), were statistically analyzed using the chi-square test, two way-repeated measures ANOVA, and Wilcoxon rank sum test, respectively (alpha = 0.05).
ResultsBased on the visual inspection, OCT images at the baseline, 72 WSLs were purely carious, 20 were non-carious (developmental) lesions, while 29 were combined (carious-developmental). The responses of WSLs over time showed to be highly variable. There was a significant difference in transitions of ICDAS scores after 3 months between carious and non-carious WSLs (p < 0.05) and non-carious and combined WSLs (p < 0.05). Carious and combined WSLs underwent significant changes in the mean BD between baseline (161.8 ± 56.8 μm) and 2 months (130.7 ± 57.4 μm) or 3 months (119.1 ± 57.5 μm) (p < 0.05), while there was no significant difference between baseline (132.2 ± 26.2 μm) and 2 months (122.8 ± 24.1 μm) or 3 months (119.8 ± 22.6 μm) in non-carious WSLs (p > 0.05). There was a significant difference in mean RR% after 2 and 3 months between carious and non-carious WSLs (p < 0.05).
ConclusionsThe remineralization capacity of WSL was variable among the cases and subjects, and depended on the WSLs history, etiology (carious, non-carious, or combined lesion) and structure (histological pattern).
Clinical relevanceCarious WSLs showed the highest remineralization potential.
相似文献To compare the remaining root canal filling material, dentin removal, apical transportation, and apical extrusion of debris after the retreatment of canals filled with bioceramic or resin-based sealers using the Reciproc or Reciproc Blue instruments.
Materials and methodsSixty mandibular molars with severely curved mesial roots were selected. The samples were initially instrumented with Reciproc (R25) and then divided into four experimental groups according to the endodontic sealer and retreatment instrument (n = 15): BC Sealer/Reciproc (BCRC), BC Sealer/Reciproc Blue (BCRB), AH Plus/Reciproc (AHRC), and AH Plus/Reciproc Blue (AHRB). The procedure time was measured, and an Eppendorf tube was used in each root canal to store the debris extrusion. The samples were scanned by micro-CT before and after retreatment. The apical transportation, volume of dentin, and filling material were evaluated.
ResultsThere were no significant differences in the reduction of the volume of obturator material or dentin removal between groups (p > .05). There were also no differences in the amount of extruded material or apical transportation (p > .05). The retreatment time for the AHRC group was significantly lower than that for the other groups (p = .004).
ConclusionsAll tested instruments obtained similar efficacy in filling material removal procedures, although no system completely removed the filling material. Retreatment of canals filled with bioceramic BC Sealer may be more time consuming.
Clinical relevanceThis study reported that Reciproc and Reciproc Blue can be indicated in retreatment of severely curved root canals filled either with bioceramic or resin-based sealers.
相似文献The study aims to evaluate the effects of non-thermal atmospheric plasma (NTAP) treatments on dentin wetting and surface free energy (SFE) and compare the effects of NTAP treatment, etch-and-rinse, and self-etch protocols for application of universal adhesives.
Materials and methodsMid-coronal dentin of intact third molars was used to measure contact angles of distilled water, ethylene-glycol, and diiodomethane and calculate SFE following different NTAP preset treatments (feeding gas consisting of pure He, He + 1% O2, He + 1.5% O2), power input (1 or 3 W), and tip-to-surface distance (2, 4, or 8 mm). Contact angles of reference liquids and SFE of dentin following He + 1.5% O2 at 3-W and 4-mm treatment was compared to phosphoric acid etching. Contact angles of Single Bond Universal (SBU; 3M ESPE) and Clearfil Universal Bond (CUB; Kuraray Noritake) were measured following NTAP, etch-and-rinse, and self-etch protocols.
ResultsNTAP significantly reduced contact angles of reference liquids and increased dentin SFE compared to untreated dentin (p < 0.05). O2 intensified the effect of He NTAP (p < 0.05). NTAP and phosphoric acid increased dentin polarity and Lewis base surface characteristics. Phosphoric acid increased contact angles of adhesives compared to the self-etch protocol (p < 0.05). NTAP resulted in lower adhesive contact angles than phosphoric acid, the difference being statistically significant for CUB (p < 0.05). Compared to the self-etch protocol, NTAP slightly reduced CUB contact angle but not that of SBU (p > 0.05).
ConclusionsHe NTAP with and without O2 increased dentin wetting and SFE, surpassing the effect of phosphoric acid and lowering adhesive contact angles. NTAP produced no apparent micro-morphological changes on dentin surface comparable to acid etching.
Clinical significanceNTAP treatment of dentin prior to adhesive application increases dentin wetting and surface free energy facilitating better adhesive distribution on dentin surface compared to phosphoric acid etching and similar to the “self-etch” application protocol.
相似文献The aim of this study is to evaluate the long-term clinical performance of a glass ionomer (GI) restorative system in the restoration of posterior teeth compared with a micro-filled hybrid posterior composite.
Materials and methodsA total of 140 (80 Cl1 and 60 Cl2) lesions in 59 patients were restored with a GI system (Equia) or a micro hybrid composite (Gradia Direct). Restorations were evaluated at baseline and yearly during 6 years according to the modified-USPHS criteria. Negative replicas at each recall were observed under SEM to evaluate surface characteristics. Data were analyzed with Cohcran’s Q and McNemar’s tests (p < 0.05).
ResultsOne hundred fifteen (70 Cl1 and 45 Cl2) restorations were evaluated in 47 patients with a recall rate of 79.6% at 6 years. Significant differences were found in marginal adaptation and marginal discoloration for both restorative materials for Cl1 and Cl2 restorations (p < 0.05). However, none of the materials were superior to the other (p > 0.05). A significant decrease in color match was observed in Equia restorations (p < 0.05). Only one Cl2 Equia restoration was missing at 3 years and another one at 4 years. No failures were observed at 5 and 6 years. Both materials exhibited clinically successful performance after 6 years. SEM evaluations were in accordance with the clinical findings.
ConclusionsBoth materials showed a good clinical performance for the restoration of posterior teeth during the 6-year evaluation.
Clinical relevanceThe clinical effectiveness of Equia and Gradia Direct Posterior was acceptable in Cl1 and Cl2 cavities subsequent to 6-year evaluation.
相似文献The study was aimed at comparing implants installed with guided and conventional surgery.
Material and methodsTwenty-nine total edentulous patients were selected, and maxillary contralateral quadrants were randomly assigned to static computer-aided implant surgery (S-CAIS): flapless computer-guided surgery, and conventional surgery (CS): flap surgery with conventional planning. Tomography scans were performed at baseline and 10 days after the surgery for deviation measurement, and radiography was done at baseline and after 6 and 12 months, for peri-implant bone level (PIBL) analysis. Peri-implant fluid and subgingival biofilm were collected to evaluate bone markers and periodontal pathogens.
ResultsS-CAIS showed less linear deviation at the apical point and the midpoint and less angular deviation (p < 0.05), with greater depth discrepancy in the positioning of the platform (p < 0.05). Higher values of vertical PIBL were observed for the S-CAIS group at baseline (p < 0.05), while lower values of horizontal PIBL were observed for CS (p < 0.05). Bone markers and Tf presented higher levels in CS (p < 0.05). Flapless S-CAIS allowed smaller linear and angular deviations than the conventional technique.
ConclusionHowever, PIBL was higher in S-CAIS; the conventional technique led to a greater angiogenic and bone remodeling activity by elevating the angiogenic levels and bone markers.
Clinical relevanceEvaluating the different implant insertion techniques can guide clinical and surgical regarding the accuracy, the release pattern of bone markers, and the peri-implant bone level.
Trial registrationReBEC-RBR-8556fzp.
相似文献The purpose of the study is to evaluate and compare the effectiveness of honey mouthwash and an oral care protocol on mucositis and weight loss in patients with acute myeloid leukemia receiving chemotherapy.
Materials and methodsIn this single-blind clinical trial, 53 acute myeloid leukemia (AML) patients receiving chemotherapy were randomly assigned into three groups: honey mouthwash (n = 17), oral care (n = 17), and control (n = 19). The severity of mucositis and weights was examined blindly at the baseline and 4-week follow-up.
ResultsThe prevalence of grades of mucositis in the study groups was significant at the end of the third (p = 0.002) and fourth (p < 0.001) weeks. The mucositis severity decreased at the end of the third and fourth weeks in the honey mouthwash group (p < 0.05), whereas it increased in the control group (p < 0.001). The difference in the weight was significant between the honey mouthwash and the control groups (p < 0.05, MD = 1.95) at the end of the third week, and between the honey mouthwash group with the control (p < 0.01, MD = 2.92) and oral care groups (p < 0.05, MD = 1.95) at the end of the fourth week.
ConclusionsHoney mouthwash is effective in preventing and reducing the severity of mucositis, and weight loss and can be recommended for patients undergoing chemotherapy.
Clinical relevanceThe results of this study suggest that honey mouthwash can reduce the incidence and severity of mucositis in patients, reduce or eliminate the possibility of weight loss in them, as well as encourage some weight gain. Compared to routine oral care, honey mouthwash is also easier to use and handle.
Trial registrationIRCT2015121419919N7
相似文献To obtain radicular measurements of two separate mesiobuccal (MB) root canals in maxillary first molars using micro-computed tomography (μCT) with customized software.
Materials and methodsHuman maxillary first molar MB roots (N = 36) with two separate canals (MB1, MB2) and apical foramina were scanned by μCT and analyzed with Kappa2 software to reconstruct three-dimensional (3D) surface models of roots and canals. These models were sectioned at 0.1 mm intervals perpendicular to the central axis of each canal. Canal widths, 3D curvatures, and surrounding dentine thicknesses were measured concurrently on each section. Dentine thicknesses were analyzed statistically for differences between each direction and the different levels of both canals.
ResultsDentine walls around MB1 were thicker than MB2 (p < 0.05). Thinnest dentine was most often located at disto-inside direction in both canals. Canal widths were significantly smaller in MB2 than MB1 (p < 0.01). Apical constrictions were smaller (p < 0.05) and further (p < 0.05) from the apex in MB2 than MB1. Canal curvatures were greatest in the apical third of both canals (p < 0.001), and they were greater in MB2 than MB1 (p < 0.05).
ConclusionsMB2 canals had shorter lengths, smaller widths, and more severe curvatures and were surrounded by thinner dentine walls. In MB2, apical constrictions were between 1 and 2 mm from the apex, compared to about 1 mm for MB1.
Clinical relevanceThese detailed measurements and in-depth 3D analyses of maxillary first molar MB roots with two separate canals and apical foramina provide morphologic references for root canal therapy.
相似文献To retrospectively compare the high-angled sagittal split osteotomy (HOO) and the bilateral sagittal split osteotomy (BSSO) for the correction of skeletal dysgnathias regarding intra- and postoperative complications.
MethodsThe electronic medical records of all patients treated with an orthognathic surgery at the Department for Oral, Maxillofacial and Facial Plastic Surgery, University Hospital Frankfurt, Germany, between the years 2009 and 2019 were retrospectively reviewed.
ResultsTwo hundred ninety-one patients were included. The overall complication rates were 19.78% (BSSO) compared to 12.5% (HOO) (p = 0.14). Significant differences were found regarding the operation time (HOO < BSSO, p = 0.02), material failure (HOO > BSSO, p = 0.04), and early recurrence requiring revision surgery (HOO < BSSO, p = 0.002). The use of a ramus plate significantly reduced the risk of plate failure (2.8% < 13.6%, p = 0.05). More bad splits (p = 0.08) and early sensory disorders (p = 0.07) occurred in the BSSO group.
ConclusionThe HOO presents a possible alternative to the BSSO since newly developed osteosynthesis material significantly reduces the risk of material failure. The BSSO is accompanied by higher risks of developing complications like a bad split and sensory disorders but, however, remains the standard for large anterior–posterior transpositions of the mandible.
相似文献The aim of this study was to investigate in vitro the effect of clodronate on interleukin-1ß (IL-1ß)–stimulated human periodontal ligament fibroblasts (HPdLFs) with the focus on inflammatory factors of orthodontic tooth movement with and without compressive force.
Materials and methodsHPdLFs were incubated with 5 μM clodronate and 10 ng/mL IL-1ß. After 48 h, cells were exposed to 3 h of compressive force using a centrifuge. The gene expression of cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), matrix metalloproteinase 8 (MMP-8), and the tissue inhibitor of MMP (TIMP-1) was analyzed using RT-PCR. Prostaglandin E2 (PGE-2), IL-6, and TIMP-1 protein syntheses were quantified via ELISA.
ResultsCompressive force and IL-1ß induced an overexpression of COX-2 gene expression (61.8-fold; p < 0.05 compared with control), diminished by clodronate (41.1-fold; p < 0.05 compared with control). Clodronate slowed down the compression and IL-1ß induced IL-6 gene expression (161-fold vs. 85.6-fold; p < 0.05 compared with control). TNF-α was only slightly affected without statistical significance. Clodronate reduced IL-1ß-stimulated MMP-8 expression with and without compressive force. TIMP-1 on gene and protein level was downregulated in all groups. Analyzing the MMP-8/TIMP-1 ratio, the highest ratio was detected in IL-1ß-stimulated HPdLFs with compressive force (21.2-fold; p < 0.05 compared with control). Clodronate diminished IL-1ß-induced upregulation of MMP-8/TIMP-1 ratio with (11.5-fold; p < 0.05 compared with control) and without (12.5-fold; p < 0.05 compared with control) compressive force.
ConclusionOur study demonstrates a slightly anti-inflammatory effect by clodronate under compressive force in vitro. Additionally, the periodontal remodeling presented by the MMP-8/TIMP-1 ratio seems to be diminished by clodronate.
Clinical relevanceReduction of pro-inflammatory factors and reduction of periodontal remodeling might explain reduced orthodontic tooth movement under clodronate intake.
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