This study evaluated the effects of antimicrobial photodynamic therapy (aPDT) in the alveolar repair of rats with major risk factors for bisphosphonate-related osteonecrosis of the jaws (BRONJ). ...Senile rats received 0.45 ml of vehicle (VEH and VEH/aPDT) or 0.45 ml of zoledronate (ZOL and ZOL/aPDT) every three days for seven weeks. After three weeks of treatment, the first lower left molar was extracted. VEH/aPDT and ZOL/aPDT were submitted to aPDT on the extraction site at 0, 2 and 4 days postoperatively. Euthanasia was performed 28 days postoperatively and the extraction site was evaluated by clinical, histological, histometric, histochemical and immunohistochemical analysis. ZOL showed tissue repair impairment; lower percentage of newly formed bone tissue (NFBT); higher percentage of non-vital bone tissue (NVBT); fewer mature collagen fibers and increased immunolabeling for tumor necrosis factor (TNFα), interleukin (IL)-1β and IL-6. ZOL/aPDT showed clinical and histological characteristics of the extraction site, percentage of NFBT and percentage of mature collagen fiber similar to VEH. Percentage of NVBT and immunolabeling for inflammatory cytokines in ZOL/aPDT was lower than in ZOL. Immunolabeling for tartarato-resistant acid phosphatase (TRAP) was lower in ZOL and ZOL/aPDT. aPDT in the dental extraction site improves tissue repair process and prevents the occurrence of BRONJ-like lesions after tooth extraction.
Background
The aim of the present study was to assess the periodontal condition of individuals with Down syndrome and the association with sociodemographic and behavioural characteristics and family ...perception of oral health.
Methods
This cross‐sectional observational study was performed at a referral centre for dental assistance to disabled persons in Araçatuba, Brazil. Parents of the individuals were interviewed, and the visible plaque index, bleeding on probing, probing pocket depth and clinical attachment level were recorded by one periodontist in six sites per tooth of all teeth. The individual was the unit of analysis. The significance level was set at 5%.
Results
Sixty‐four subjects (23.8 ± 8.3 years old) were included. Eighteen (28.1%) were diagnosed with gingivitis and 46 (71.9%) with periodontitis. In the multiple logistic regression final model, age and self‐reported oral hygiene practices were associated with the occurrence of periodontitis. The chance of having periodontitis was 4.7 times higher among individuals older than 20 years and approximately 4 times higher in patients whose oral hygiene was performed by themselves and their parents, compared with those who performed oral hygiene alone. Sex, follow‐up time in the centre, education, degree of participants' dependence, flossing and family history of periodontal disease were not associated with the occurrence of periodontitis. Higher levels of plaque and bleeding were observed for participants with parents reporting bad gingival health (76.2% and 46.9%) and deficient oral hygiene (79.5% and 47.3%). The perception of parents regarding gingival bleeding was correlated with higher bleeding detected clinically (P = 0.01; 50.1%).
Conclusions
The prevalence of periodontitis in individuals with Down syndrome is high and increases with age, even in the face of the parents' perception about their children's oral condition.
Background and Objective
This study assessed the effects of the local use of Saccharomyces cerevisiae as monotherapy and as an adjuvant to the mechanical treatment of ligature‐induced periodontitis ...in rats.
Material and Methods
Periodontitis was induced in 72 rats via the installation of a ligature around the mandibular first molar. After 7 d, the ligature was removed and the rats were placed in one of the following groups: no treatment (C; n = 18); scaling and root planing (SRP; n = 18); local irrigation with probiotics (PRO; n = 18); and SRP followed by local irrigation with probiotics (SRP/PRO; n = 18). Six rats from each group were killed at 7, 15 and 30 d. The histological characteristics, alveolar bone loss (ABL) and immunolabeling of tumor necrosis factor alpha (TNF‐α), interleukin‐1beta (IL‐1β), interleukin‐10 (IL‐10) and TRAP on the furcation area of the first molar were assessed.
Results
The PRO group showed features of acceleration of the tissue‐repair process during the entire experiment. On day 15, there was less ABL in the SRP/PRO group compared with the C group. There were fewer TRAP‐positive cells in the SRP and SRP/PRO groups at 30 d. There was less immunostaining for TNF‐α in the PRO and SRP/PRO groups and less immunostaining for IL‐1β in the PRO group. However, there was more immunostaining for IL‐10 in the PRO group on day 15.
Conclusion
Local use of the probiotic did not result in any adverse effects on periodontal tissues. When used as monotherapy or as an adjuvant, the probiotic was effective at controlling periodontitis in rats.
The production of sulfonated resins is of great interest to be applied in different industrial processes such as esterification, etherification, biodiesel production and water treatment. Mathematical ...models play an important role in process control and optimization, through prediction of process variables and adjustment of parameters. Currently mathematical models for resin sulfonation processes are still scarce in literature. In the present study, mathematical tools were used to build a model that is able to describe the sulfonation process of polystyrene-co-(ethylene glycol dimethacrylate) particles. The diffusion and rate coefficients were estimated through comparison between the model and the experimental data and presented coherent values. An average activation energy of 170 kJ/mol was obtained for the sulfonation reaction. The results revealed that, for the conditions studied herein, the process is diffusion-controlled and can be represented by the shrinking core model, considering irreversible pseudo-first order reaction for sulfuric acid.
We sought to evaluate the effects of non-surgical periodontal treatment (NSPT) on periodontal clinical parameters, systemic blood pressure (BP), and plasma levels of systemic inflammation markers in ...patients with combined refractory arterial hypertension (RAH) and stage III grade B periodontitis. Twenty-seven participants with RAH and periodontitis received NSPT. The analyzed clinical parameters were probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), and plaque index (PI). An assessment was performed for systemic BP, complete blood count, coagulogram, creatinine measurement, C-reactive protein (CRP), glycated hemoglobin, cholesterol, glutamic oxaloacetic transaminase, glutamate pyruvic transaminase, waist-hip ratio, and body mass index. In the follow-up period, twenty-two patients were evaluated at baseline and after 90 and 180 days. The data were submitted for statistical analysis (α = 0.05%). As expected, the clinical results showed a significant improvement in the percentages of PI, BOP, PD, and CAL, which were statistically significant at 90 and 180 days (
< 0.0001). Importantly, NSPT significantly reduced the blood level of CRP (
< 0.02). However, no significant reduction in BP parameters was noted in the evaluated follow-up periods. NSPT, despite the benefits in periodontal clinical parameters, reduced the plasma level of CRP but not the BP in patients with combined RAH and periodontitis.
ABSTRACT Most sandy soils have low natural fertility and low levels of organic matter, making nitrogen (N) fertilization essential. Thus, five doses of N were applied (0, 75, 125, 175 and 225mg dm-³) ...in a randomized block design to evaluate the effects of nitrogen fertilization on the morphogenetic, structural and production characteristics of Brachiaria brizantha cv. Marandu in a Quartzarenic neosoil. The doses of N did not affect the height of the canopy. The leaf elongation rate, final leaf length and number of live leaves increased linearly at the doses of N. Leaf appearance rate, stem elongation rate, leaf lifespan, phyllochron, leaf senescence rate and tiller density showed a quadratic response to the rates There was also an effect of N rates in herbage mass, leaf mass, stem mass, which increased linearly. Brachiaria brizantha cv. Marandu cultivated in Quartzarenic neosoil requires higher doses of N, 175 and 225mg dm-³. Under these conditions, increases in its morphogenetic, structural and productive characteristics are observed. These findings may not be repeated in the most fertile soils with the greatest capacity to supply N.
RESUMO A maioria dos solos arenosos tem baixa fertilidade natural e baixos teores de matéria orgânica, tornando a adubação com nitrogênio (N) essencial. Assim, foram aplicadas cinco doses de N (0, 75, 125, 175 e 225mg dm-³) em delineamento de blocos ao acaso, para se avaliarem os efeitos da adubação com nitrogênio nas características morfogênicas, estruturais e produtivas da Brachiaria brizantha cv. Marandu, em um Neossolo Quartzarênico. As doses de N não afetaram a altura do dossel. A taxa de alongamento foliar, o comprimento final da folha e o número de folhas vivas aumentaram linearmente em função das doses de N. A taxa de aparecimento de folhas, a taxa de alongamento do caule, o tempo de vida da folha, o filocrono, a taxa de senescência foliar e a densidade de perfilhos apresentaram resposta quadrática às doses de N. A massa da forragem, a massa foliar e a massa do caule aumentaram linearmente. Brachiaria brizantha cv. Marandu cultivada em Neossolo Quartzarênico requer maiores doses de N, 175 e 225mg dm-³. Nessas condições, são observados aumentos em suas características morfogenéticas, estruturais e produtivas. Esses achados podem não se repetir nos solos mais férteis e com maior capacidade de suprir N.
Background and Objective
This study aimed to assess the effect of multiple sessions of a low‐level laser therapy (LLLT) adjuvant to scaling and root planing (SRP) on the treatment of experimental ...periodontitis (EP) in rats treated with 5‐fluorouracil (5‐FU).
Material and Methods
A total of 120 rats were divided into five groups: no treatment (NT); treatment with 5‐FU (60 and 40 mg/kg) and no local periodontal treatment (5FU); treatment with 5‐FU and SRP (5FU‐SRP); treatment with 5‐FU, SRP and one LLLT session (660 nm; 0.035 W; 4.2 J; 120 s) (5FU‐SRP‐1LLLT); and treatment with 5‐FU, SRP and four LLLT sessions (0, 24, 48 and 72 h) (5FU‐SRP‐4LLLT). EP was induced in the mandibular molars through ligature placement. The alveolar bone loss (ABL) area in the furcation region was analysed histometrically. TRAP, proliferating cell nuclear antigen, RANKL, osteoprotegerin and activated caspase‐3 patterns were analysed by immunolabeling. Prostaglandin E2 was quantified using an ELISA, and tumour necrosis factor α and interleukin‐6 were assessed using the multiplex method. The prevalence rates of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia and Fusobacterium nucleatum were assessed using the PCR method. The data were subjected to statistical analysis (α = 5%).
Results
5FU, 5FU‐SRP and 5FU‐SRP‐1LLLT treatment groups showed higher ABL compared with the NT group (p < 0.05), whereas the 5FU‐SRP‐4LLLT group showed lower ABL compared with the 5FU group on day 7 and decreased RANKL immunolabeling (p < 0.05).
Conclusion
Treatment with 5‐FU worsened EP, and multiple LLLT sessions adjuvant to SRP seemed to improve periodontitis in rats subjected to 5‐FU chemotherapy.
The aim of the present study was to compare the effects of Er:YAG and diode laser treatments of the root surface on intrapulpal temperature after scaling and root planing with hand instruments.
...Fifteen extracted single-rooted teeth were scaled and root planed with hand instruments. The teeth were divided into 3 groups of 5 each and irradiated on their buccal and lingual surfaces: group A: Er:YAG laser, 2.94 microm/100 mJ/10 Hz/30 seconds; group B: diode laser, 810 nm/1.0 W/0.05 ms/30 seconds; group C: diode laser, 810 nm/1.4 W/0.05 ms/30 seconds. The temperature was monitored by means of a type T thermocouple (copper-constantan) positioned in the pulp chamber to assess pulpal temperature during and before irradiation. Afterwards, the specimens were longitudinally sectioned, and the buccal and lingual surfaces of each root were analyzed by scanning electron microscopy.
In the Er:YAG laser group, the thermal analysis revealed an average temperature of -2.2 +/- 1.5 degrees C, while in the diode laser groups, temperatures were 1.6 +/- 0.8 degrees C at 1.0 W and 3.3 +/- 1.0 degrees C at 1.4 W. Electronic micrographs revealed that there were no significant morphological changes, such as charring, melting, or fusion, in any group, although the specimens were found to be more irregular in the Er:YAG laser group.
The application of Er:YAG and diode lasers at the utilized parameters did not induce high pulpal temperatures. Root surface irregularities were more pronounced after irradiation with an Er:YAG laser than with a diode laser.
The production of polymeric resins through free-radical copolymerization is an interesting procedure from an economic standpoint; however, its mathematical representation is of great complexity. In ...the present study, modeling tools were used to describe the copolymerization of styrene with ethylene glycol dimethacrylate (EGDMA) beyond the gel point. Balance of species and sequences, method of moments, and numerical fractionation technique were applied in the model's kinetic description. Diffusion effects were also taken into account. The concept of elementary gel structures (EGSs) was used in order to predict textural properties of polymer particles, such as specific surface area and swollen gel volume. Suspension copolymerizations were carried out in the presence of toluene/heptane mixtures, and data on these reactions were used to assess the model's predictability. Reactivity parameters showed similarities to styrene/divinylbenzene systems. Agreement between the model and experimental data improved when diffusion effects were considered. The fitted apparent coiling factors for dry particles were found in the range of 0.368–0.406, and a linear correlation was obtained between this parameter and toluene fraction (a good solvent), being consistent with the pore formation phenomenon.
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•A copolymerization model including post-gelation prediction was developed.•Specific surface area of gel particles can be calculated through EGS concept.•Swollen volume of particles can also be estimated during polymerization simulation.
The repair of bone defects has been the subject of many studies that have shown inconclusive results as to what is the best bone substitute.
Bone defects (Ø 2 mm) were induced on the tibia of ...seventy-two rats, which were distributed into the following four groups/treatments (n=18 each): Control: no treatment; EMD: enamel matrix derived protein; PBM: photobiomodulation therapy (660 nm, 0,035 W, 60 s); EMD + PBM: EMD and immediate treatment with PBM (660 nm, 0,035 W, 60 s). Six animals from each group were euthanized after 10, 30 and 60 days. Histological and immunohistochemistry analyses (osteocalcin - OCN and tartrate-resistant acid phosphatase - TRAP) were performed with scores for each of the biological events.
All performed treatments resulted in an increased filling and maturation of bone tissue, being greater in the EMD and EMD + PBM groups in the 30 day period, compared to the Control group. The immunostaining of OCN was greater at 60 days in all treated groups than in the Control over the same period. TRAP immunostaining was higher at 30 days in all treated groups, and lower in groups EMD and PBM after 60 days, compared to the Control over the same period. There was greater immunostaining in the EMD + PBM group after 10 days than in the Control and EMD groups in the same period.
These results lead to the conclusion that treatments with EMD and PBM, both separate and in association were effective in filling and maturing bone tissue in tibial bone cavities, with greater effectiveness in the period of 30 days in the EMD and EMD + PBM groups.
Enamel matrix proteins, low-level laser, bone, animal research.
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