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1.
Mol Syst Biol ; 20(5): 573-589, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38531971

RESUMO

Characterising RNA-protein interaction dynamics is fundamental to understand how bacteria respond to their environment. In this study, we have analysed the dynamics of 91% of the Escherichia coli expressed proteome and the RNA-interaction properties of 271 RNA-binding proteins (RBPs) at different growth phases. We find that 68% of RBPs differentially bind RNA across growth phases and characterise 17 previously unannotated proteins as bacterial RBPs including YfiF, a ncRNA-binding protein. While these new RBPs are mostly present in Proteobacteria, two of them are orthologs of human mitochondrial proteins associated with rare metabolic disorders. Moreover, we reveal novel RBP functions for proteins such as the chaperone HtpG, a new stationary phase tRNA-binding protein. For the first time, the dynamics of the bacterial RBPome have been interrogated, showcasing how this approach can reveal the function of uncharacterised proteins and identify critical RNA-protein interactions for cell growth which could inform new antimicrobial therapies.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , RNA Bacteriano , Proteínas de Ligação a RNA , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , RNA Bacteriano/metabolismo , RNA Bacteriano/genética , Proteoma/metabolismo , Ligação Proteica , Regulação Bacteriana da Expressão Gênica , Humanos
2.
Proc Natl Acad Sci U S A ; 119(37): e2110342119, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36067284

RESUMO

To swim and navigate, motile bacteria synthesize a complex motility machinery involving flagella, motors, and a sensory system. A myriad of studies has elucidated the molecular processes involved, but less is known about the coordination of motility expression with cellular physiology: In Escherichia coli, motility genes are strongly up-regulated in nutrient-poor conditions compared to nutrient-replete conditions; yet a quantitative link to cellular motility has not been developed. Here, we systematically investigated gene expression, swimming behavior, cell growth, and available proteomics data across a broad spectrum of exponential growth conditions. Our results suggest that cells up-regulate the expression of motility genes at slow growth to compensate for reduction in cell size, such that the number of flagella per cell is maintained across conditions. The observed four or five flagella per cell is the minimum number needed to keep the majority of cells motile. This simple regulatory objective allows E. coli cells to remain motile across a broad range of growth conditions, while keeping the biosynthetic and energetic demands to establish and drive the motility machinery at the minimum needed. Given the strong reduction in flagella synthesis resulting from cell size increases at fast growth, our findings also provide a different physiological perspective on bacterial cell size control: A larger cell size at fast growth is an efficient strategy to increase the allocation of cellular resources to the synthesis of those proteins required for biomass synthesis and growth, while maintaining processes such as motility that are only needed on a per-cell basis.


Assuntos
Quimiotaxia , Proteínas de Escherichia coli , Escherichia coli , Quimiotaxia/genética , Escherichia coli/citologia , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Flagelos/metabolismo , Expressão Gênica , Regulação Bacteriana da Expressão Gênica
3.
J Clin Periodontol ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561985

RESUMO

AIM: To apply high-frequency ultrasound (HFUS) echo intensity for characterizing peri-implant tissues at healthy and diseased sites and to investigate the possible ultrasonographic markers of health versus disease. MATERIALS AND METHODS: Sixty patients presenting 60 implants diagnosed as healthy (N = 30) and peri-implantitis (N = 30) were assessed with HFUS. HFUS scans were imported into a software where first-order greyscale outcomes [i.e., mean echo intensity (EI)] and second-order greyscale outcomes were assessed. Other ultrasonographic outcomes of interest involved the vertical extension of the hypoechoic supracrestal area (HSA), soft-tissue area (STA) and buccal bone dehiscence (BBD), among others. RESULTS: HFUS EI mean values obtained from peri-implant soft tissue at healthy and diseased sites were 122.9 ± 19.7 and 107.9 ± 24.7 grey levels (GL); p = .02, respectively. All the diseased sites showed the appearance of an HSA that was not present in healthy implants (area under the curve = 1). The proportion of HSA/STA was 37.9% ± 14.8%. Regression analysis showed that EI of the peri-implant soft tissue was significantly different between healthy and peri-implantitis sites (odds ratio 0.97 [95% confidence interval: 0.94-0.99], p = .019). CONCLUSIONS: HFUS EI characterization of peri-implant tissues shows a significant difference between healthy and diseased sites. HFUS EI and the presence/absence of an HSA may be valid diagnostic ultrasonographic markers to discriminate peri-implant health status.

4.
Biophys J ; 122(16): 3207-3218, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37403359

RESUMO

Bacterial cells that stop growing but maintain viability and the capability to regrow are termed dormant and have been shown to transiently tolerate high concentrations of antimicrobials. Links between tolerance and cellular energetics as a possible explanation for the tolerance, have been investigated and have produced mixed and seemingly contradictory results. Because dormancy merely indicates growth arrest, which can be induced by various stimuli, we hypothesize that dormant cells may exist in a range of energetic states that depend on the environment. To energetically characterize different dormancies, we first induce them in a way that results in dormant populations and subsequently measure both of their main energy sources, the proton motive force magnitude and the concentration of ATP. We find that different types of dormancy exhibit characteristic energetic profiles that vary in level and dynamics. The energetic makeup was associated with survival to some antibiotics but not others. Our findings portray dormancy as a state that is rich in phenotypes with various stress survival capabilities. Because environmental conditions outside of the lab often halt or limit microbial growth, a typologization of dormant states may yield relevant insights on the survival and evolutionary strategies of these organisms.


Assuntos
Antibacterianos , Bactérias , Antibacterianos/farmacologia
5.
Periodontol 2000 ; 91(1): 182-198, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35950734

RESUMO

The aim of this study was to compare patient-reported outcome measures (PROMs) of soft tissue substitutes versus autogenous grafts for soft tissue augmentation procedures at implant sites. Comprehensive and systematic literature searches were performed until December 2021. A focused question was formulated based on the Population, Intervention, Comparison and Outcome criteria (PICO): In patients with dental implants undergoing soft tissue augmentation (P), do soft tissue substitutes (I) compared to autogenous soft tissue graft (SCTG [subepithelial connective tissue graft]) (C) limit the post-operative morbidity and other patient reported-outcomes measures (O). Randomized controlled clinical trials, prospective-, retrospective- and case-series studies were included. Meta-analyses were performed whenever possible and the results were expressed as weighted mean differences (WMD). A total of 29 clinical studies were included. For mucosal thickness gain, soft tissue substitutes significantly reduced the pain perception compared to SCTG (n = 4; WMD = 14.91 Visual Analog Scale [VAS] units; 95% confidence interval [CI] 6.42-23.40; P < .0006) based on a 0-100 VAS scale. Based on a 0-10 VAS scale, a borderline significance of pain reduction was found when soft tissue substitutes were applied (n = 4; WMD = 1.62 VAS units; 95% CI 0.01-3.23; P = .05). For keratinized tissue gain, soft tissue substitutes significantly reduced the pain perception after keratinized tissue augmentation compared to SCTG based on a 0-100 VAS scale (n = 2; WMD = 21.43 VAS units; 95% CI 12.58-30.28; P < .0001). Based on the 0-10 VAS scale, soft tissue substitutes significantly reduced the pain as compared to SCTG (n = 4; WMD = 1.65 VAS units; 95% CI 0.66-2.64; P = .001). Regarding pain medication, soft tissue substitutes required less painkillers (n = 6; WMD = 1.56 tablets; 95% CI 1.22-1.91; P < .00001) after soft tissue augmentation. The surgery time was significantly reduced when soft tissue substitutes were used (n = 5; WMD = 10.9 minutes; 95% CI 4.60-17.19; P < .00001). There were no significant differences in satisfaction, aesthetics, and quality of life (OHIP-14) between soft tissue substitutes and autogenous grafts following soft tissue augmentation at implants sites. Soft tissue substitutes, compared to autogenous grafts, significantly improve PROMs following soft tissue augmentation at implant sites. Soft tissue substitutes can reduce pain perception, amounts of painkillers and surgery time while achieving similar levels of patient´s satisfaction as autogenous grafts without impairing the clinical outcomes. The current evidence indicates that they constitute a valid and reliable alternative to minimize the invasiveness in soft tissue augmentation procedures at implant sites.


Assuntos
Implantes Dentários , Humanos , Gengiva/cirurgia , Colágeno/uso terapêutico , Tecido Conjuntivo/transplante , Estudos Prospectivos , Qualidade de Vida , Estudos Retrospectivos , Dor
6.
J Clin Periodontol ; 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37861110

RESUMO

AIM: To assess the Doppler ultrasonographic tissue perfusion at dental implant sites augmented with connective tissue graft (CTG) using coronally advanced flap (CAF) or tunnel technique (TUN). MATERIALS AND METHODS: Twenty-eight patients presenting with isolated healthy peri-implant soft-tissue dehiscence (PSTD) were included in this randomized clinical trial. PSTDs were treated with either CAF + CTG or TUN + CTG. Ultrasound scans were taken at baseline, 1 week, 1 month, 6 months and 12 months. Tissue perfusion at the mid-facial, mesial and distal aspects of the implant sites was assessed by colour Doppler velocity (CDV) and power Doppler imaging (PDI). Early vascularization of the graft and the flap at 1 week and at 1 month were evaluated via dynamic tissue perfusion measurements (DTPMs), including flow intensity (FI), mean perfusion relief intensity (pRI) and mean perfused area (pA). RESULTS: Regression analysis did not reveal significant differences in terms of mid-facial CDV and PDI changes between CAF and TUN over 12 months (p > .05), while significant differences between the two groups were observed at the interproximal areas (p < .001 for both CDV and PDI changes). Higher early DTPMs were observed at the TUN-treated sites in terms of mean FI of the graft (p = .027) and mean FI (p = .024) and pRI of the flap (p = .031) compared with CAF-treated sites at 1 week. Assessment of the FI direction showed that CTG perfusion at 1 week and at 1 month mainly occurred from the flap towards the implant/bone. Early tissue perfusion outcomes were found to be associated with the 12-month mean PSTD coverage and mucosal thickness gain. CONCLUSIONS: Doppler ultrasonography shows tissue perfusion changes occurring at implant sites augmented with CTG. The main differences in tissue perfusion between CAF and TUN were observed at the interproximal sites, with early perfusion associated with clinical and volumetric outcomes at 12 months.

7.
J Clin Periodontol ; 50(7): 980-995, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36935199

RESUMO

AIM: To evaluate the efficacy of coronally advanced flap (CAF) versus tunnel technique (TUN) in covering isolated mid-facial peri-implant soft tissue dehiscences (PSTDs). MATERIALS AND METHODS: Twenty-eight participants presenting with isolated non-molar implants exhibiting PSTDs were enrolled and randomized to receive either CAF or TUN, both with a connective tissue graft (CTG). The primary outcome of the study was the percentage of mean PSTD coverage at 12 months. Secondary endpoints included the frequency of complete PSTD coverage, changes in keratinized mucosa width (KMW) and horizontal mucosal thickness (MT), as assessed with transgingival probing, 3D optical scanning and ultrasonography, professional aesthetic evaluation and patient-reported outcome measures (PROMs). RESULTS: At 12 months, the mean PSTD coverage of the CAF and TUN groups was 90.23% and 59.76%, respectively (p = .03). CAF-treated sites showed a substantially higher frequency of complete PSTD coverage (p = .07), together with significantly greater gain of KMW (p = .01), increase in MT (p = .02), volumetric gain (p < .01) and professional aesthetic outcomes (p = .01). Both interventions showed an improvement in patient-reported aesthetics and a reduction of the anxiety related to the appearance of the implant compared to baseline, with the CAF group obtaining significantly higher scores (p = .03 for both PROMs). CONCLUSIONS: CAF + CTG resulted in superior PSTD coverage outcomes, greater gain in KMW and MT, and better PROMs than TUN + CTG for the treatment of isolated PSTDs (ClinicalTrials.gov NCT03498911).


Assuntos
Gengiva , Retração Gengival , Humanos , Gengiva/cirurgia , Retração Gengival/cirurgia , Resultado do Tratamento , Raiz Dentária/cirurgia , Estética Dentária , Tecido Conjuntivo/transplante
8.
Clin Oral Implants Res ; 34 Suppl 26: 28-42, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37750532

RESUMO

OBJECTIVES: To review the available literature on the medium- and long-term effects of soft tissue augmentation (STA) at implant sites and to explore the effects of the different approaches on clinical-, patient-reported, and health-related parameters. MATERIALS AND METHODS: A comprehensive electronic and manual search was performed to identify prospective clinical studies that assessed the medium- and long-term (≥36 months) outcomes following STA, including number of sites maintaining peri-implant health and number of sites developing peri-implant disease, incidence of complications, stability of the clinical, volumetric, and radiographic parameters, and patient-reported outcome measures (PROMs). RESULTS: Fifteen studies were included in the qualitative analysis. STA was performed with either a bilaminar- or an apically positioned flap (APF) approach, in combination with autogenous grafts (free gingival graft [FGG] and connective tissue graft [CTG]) or substitutes (acellular dermal matrix [ADM] and xenogeneic cross-linked collagen matrix [CCM]). An overall high survival rate was observed. Most of the augmented implant sites maintained peri-implant health in the medium and long term, with the incidence of peri-implant mucositis and peri-implantitis ranging from 0% to 50% and from 0% to 7.14%, respectively. The position of the soft tissue margin following APF + FGG and bilaminar approaches involving CTG or CCM was found to be stable over time. No substantial changes were reported for plaque score/index, bleeding on probing/bleeding index, and probing depth between early time points and following visits. CTG-based STA procedures resulted in a stable or increased dimension of keratinized mucosa width (KMW) and mucosal thickness (MT)/volumetric outcomes over time, when compared with early follow-ups. Most of the included studies described stable marginal bone levels at the grafted implant sites over time. No substantial changes for patient-reported outcomes and professionally assessed esthetic results were reported at different time points. CONCLUSIONS: Implants that received STA showed overall high survival rate and relatively low incidence of peri-implantitis in the medium and long term. Augmented sites seem to maintain the level of soft tissue margin and marginal bone over time, while non-augmented implants may exhibit apical shift of the soft tissue margin. The overall favorable early outcomes obtained with STA are maintained in the medium and long term, with an increase in KMW and MT that may be expected over time at CTG-augmented sites.


Assuntos
Derme Acelular , Implantes Dentários , Procedimentos Cirúrgicos Bucais , Peri-Implantite , Humanos , Estudos Prospectivos , Implantes Dentários/efeitos adversos
9.
J Esthet Restor Dent ; 35(8): 1264-1270, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37317633

RESUMO

STATEMENT OF PROBLEM: Emerging evidence indicates that the emergence profile and subsequent restorative angle play a crucial role in clinical outcomes and can potentially affect the development and progression of peri-implant diseases. However, the traditional evaluation of the emergence profile and angle has been limited to mesial and distal sites using periapical x-rays, without considering the buccal sites. PURPOSE: To describe a novel 3D method to estimate the emergence profile and restorative angles around single implant-supported crowns including buccal sites. MATERIALS AND METHODS: A total of 30 implant-supported crowns (11 molars, 8 premolars, 8 central incisors and 1 canine) were extra-orally scanned using an intraoral scanner and the STL files produced were imported into a 3D software. The crown/abutment interface of each crown was delineated, and apico-coronal lines were automatically drawn following the shape of the crown. Three reference points were defined on the apico-coronal lines at the transition edge of the biological (BC) and the esthetic zone (EC) and the resulting angles were then calculated. The reliability of the measurements (2D and 3D) were assessed using the intraclass correlation coefficient (ICC). RESULTS: In anterior restorations, the mean angle of the esthetic zone amounted to 162 ± 14° at mesial sites, to 140 ± 10° at buccal sites and to 163 ± 11° at distal sites. The corresponding angles at the biological zones, amounted to 155 ± 13° at mesial sites, 139 ± 15° at buccal sites and 157 ± 5° at distal sites. In posterior restorations, the mean angle of the esthetic zone amounted to 162 ± 12° at mesial sites, to 157 ± 13 at buccal sites and to 162 ± 11 at distal sites. The corresponding angles at the biological zone, amounted to 158 ± 8 at mesial sites, 150 ± 15° at buccal sites and 156 ± 10 at distal sites. The ICC for all measurements ranged between 0.77 and 0.99 indicating a good intra-examiner reliability. CONCLUSION: Within the limitations of the present study, the 3D analysis seems to be a reliable and applicable method for the quantitative evaluation of the emergence profile in daily practice. Future randomized clinical trials are needed to assess whether a 3D analysis with the ensuing the emergence profile serves as a predictor for clinical outcomes. CLINICAL SIGNIFICANCE: The development and implementation of a 3D workflow will provide technicians and dentists with the ability to assess the restorative angle of implant-supported restorations during the provisional phase and the final restoration. This approach may help achieve an aesthetically pleasing restoration while minimizing potential clinical complications.


Assuntos
Implantes Dentários para Um Único Dente , Reprodutibilidade dos Testes , Coroas , Dente Pré-Molar , Estética Dentária , Prótese Dentária Fixada por Implante
10.
J Esthet Restor Dent ; 35(1): 197-205, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36165402

RESUMO

OBJECTIVES: To describe the methodology of the "L-shape" technique in guided bone regeneration (GBR) with simultaneous implant placement and report on the clinical, esthetic, and patient satisfaction outcomes up to 14 years of follow-up. MATERIAL AND METHODS: Fourteen patients treated with the "L-shape" technique were included in this retrospective study. The L-shape technique was performed by trimming and placing a soft-type bone block made of deproteinized bovine bone mineral with 10% collagen at the buccal-occlusal aspect of the dental implant. The remaining gaps were filled with deproteinized bovine bone mineral granules and the augmented area was covered with a collagen membrane. The following parameters were recorded:  probing depth (PD), bleeding on probing (BOP), plaque index (PI), keratinized tissue width (KT) and marginal bone level (MBL). Esthetic outcomes were assessed according to the pink esthetic score (PES) and the white esthetic score (WES). Patient satisfaction was evaluated by means of a numerical rating scale (0-10). The stability of each augmented site was assessed by measuring the volumetric changes between baseline (crown delivery) and the respective follow-up. RESULTS: A total of 13 maxillary incisors and one maxillary canine in 14 patients were included. The mean follow-up period was 7.7 ± 3.8 years. PES values amounted to 10.7 ± 3.3 and WES to 8.8 ± 1.4. Patient satisfaction reached 9.4 ± 0.8. Mean PD at implant sites were 2.7 ± 0.7 mm while BOP amounted to 15.0 ± 0.2% and Pl to 5.0 ± 0.0%. Volumetric analyses revealed minimal changes at the augmented sites irrespective of the region of interest. Radiographic MBL remained relatively stable. CONCLUSIONS: Within the limitation of the present study the L-shape augmentation procedure seems to be a reliable technique when performing GBR with simultaneous implant placement in the esthetic zone. Outcomes encompassed stable clinical and esthetic results accompanied by high levels of patient satisfaction. Future randomized controlled trials are warranted to confirm possible benefits of the L-shape technique over traditional approaches. CLINICAL SIGNIFICANCE: The L-shape appears to be a simple yet promising technique in GBR with simultaneous implant placement that can easily be translated into clinical practice.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários para Um Único Dente , Animais , Bovinos , Implantação Dentária Endóssea/métodos , Estudos Retrospectivos , Resultado do Tratamento , Estética Dentária , Regeneração Óssea , Maxila/cirurgia
11.
Int J Dent Hyg ; 21(2): 417-425, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36385592

RESUMO

OBJECTIVE: Morning breath is a temporary and unpleasant malodour sourced from the mouth, which occurs upon awakening. This double-blind, crossover, randomized clinical trial aimed to evaluate the bad-breath suppression of three commercially available mouthwashes: Mentadent Professional® Chlorhexidine 0.05% with vitamin C (ChxC), Meridol Alito Sicuro® (SnF2 ) and CB12® (ZnChx) compared to a placebo (PbO) on morning halitosis. METHODS: Thirty-two subjects refraining from oral hygiene practices for 12 h before the evaluation, performed a 30-s rinse with 15 ml of mouthwash, followed by a 5-s gargle, in the evening before bedtime. In order to assess morning halitosis, visual inspection (Winkel Tongue Coating Index), organoleptic (Rosenberg index) and chromatographic measurements were used. Gas chromatography was carried out by means of a dedicated device, the Oral Chroma. The recorded measurements have to be considered solely after the rinse since no data about the pre-exposure were available. A washout period of 1 week passed between one administration and the next. RESULTS: The mean value of the organoleptic indices after administration of ChxC mouthwash is similar to ZnChx, SnF2 and PbO values. Thus, no statistically significant differences were recorded among the mouthwashes and PbO. Nevertheless, ChxC seems to be more efficient in comparison with the PbO regarding VSCs levels analysed with Oral Chroma, (CH3 SH; p = 0.0081) and [(CH3 )2 S; p = 0.0003]. CONCLUSION: Considering our limited sample, instrumental examination demonstrated that the use of the analysed mouthwashes can result in low VSCs levels after 12 h from a single rinse. Furthermore, the highest number of patients (n = 14) were proved to be free from bad smell after using a single administration of ChxC with respect to the other commercial products. The other tested mouthwashes did not show better performances with respect to the placebo after a single rinse.


Assuntos
Halitose , Antissépticos Bucais , Humanos , Antissépticos Bucais/uso terapêutico , Antissépticos Bucais/farmacologia , Halitose/prevenção & controle , Clorexidina/uso terapêutico , Higiene Bucal/métodos , Método Duplo-Cego , Língua , Estudos Cross-Over
12.
J Clin Periodontol ; 49(11): 1169-1184, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35871600

RESUMO

AIM: To evaluate the efficacy of recombinant human platelet-derived growth factor (rhPDGF)-BB combined with a cross-linked collagen matrix (CCM) for the treatment of multiple adjacent gingival recession type 1 defects (MAGRs) in combination with the coronally advanced flap (CAF). MATERIALS AND METHODS: Thirty patients were enrolled in this triple-blind, randomized, placebo-controlled trial and treated with either CAF + CCM + rhPDGF, or CAF + CCM + saline. The primary outcome was mean root coverage (mRC) at 6 months. Complete root coverage, gain in gingival thickness (GT), keratinized tissue width, volumetric and ultrasonographic changes, and patient-reported outcome measures were also assessed. Mixed-modelling regression analyses were used for statistical comparisons. RESULTS: At 6 months, the mRC of the CCM + rhPDGF and CCM alone groups were 88.25% and 77.72%, respectively (p = .02). A significant gain in GT was consistently observed for both treatment arms, and more so for the patients receiving the matrix containing rhPDGF through time (0.51 vs. 0.80 mm, on average, p = .01). The rhPDGF + CCM treated patients presented greater volume gain, higher soft tissue thickness, and a superior aesthetic score. CONCLUSION: rhPDGF enhances the clinical, volumetric, and aesthetic outcomes of MAGRs above the results achieved with CAF + CCM alone (ClinicalTrials.gov NCT04462237).


Assuntos
Retração Gengival , Colágeno/uso terapêutico , Tecido Conjuntivo , Estética Dentária , Retração Gengival/tratamento farmacológico , Retração Gengival/cirurgia , Humanos , Fator de Crescimento Derivado de Plaquetas , Resultado do Tratamento
13.
J Esthet Restor Dent ; 34(1): 181-187, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34936177

RESUMO

OBJECTIVE: Soft tissue augmentation (STA) at implant sites has the potential of improving peri-implant health, esthetics, and marginal bone level stability. The present study aimed at evaluating the volumetric changes occurring following implant placement in sites that received STA compared to non-augmented sites. METHODS: A total of 26 subjects received a dental implant in a posterior edentulous site. Simultaneous STA with a xenogeneic cross-linked collagen scaffold was performed for the first 13 patients, while the remaining subjects served as the negative control. An intraoral optical scanner was used at baseline and at 12 weeks to generate digital models. RESULTS: The mean volume (Vol) gain of the test group was 38.43 mm3 , while a mean Vol of -16.82 mm3 was observed for the control group (p < 0.05). The mean thickness of the reconstructed volume (ΔD) was 0.61 and -0.24 mm, for the test and control group, respectively (p < 0.05). Higher linear dimensional changes were observed for the test group (p < 0.05), while no significant differences were observed in terms of keratinized mucosa width and pocket depth changes between the two groups. CONCLUSIONS: Simultaneous STA with xenogeneic collagen scaffold obtained statistically significant higher volumetric outcomes compared to the non-augmented group. CLINICAL SIGNIFICANCE: STA at the time of implant placement using a xenogeneic cross-linked collagen scaffold can prevent remodeling of the ridge during the first 12 weeks, as compared to non-grafted implant sites.


Assuntos
Implantes Dentários , Colágeno , Implantação Dentária Endóssea , Gengiva , Humanos
14.
Int J Mol Sci ; 23(9)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35563664

RESUMO

Several types of deproteinised bovine bone mineral (DBBM) are available on the market, and each one is obtained with a thermic and chemical process that can differ, achieving different results. Currently, several protocols using low temperature are suggested to reduce the possible particle crystallisation during the production process. This study aimed to evaluate the biomorphological reaction of periodontal fibroblast cultures in contact with different DBBM particles treated with a low-temperature protocol (Thermagen®) and without exposure to sodium hydroxide (NaOH). Morphological evaluation was performed using light, confocal laser, and scanning electron microscopy, and the biological reaction in terms of proliferation was performed using an XTT proliferation assay at 24 h (T1), 72 h (T2), and 7 days (T3). The morphological analysis highlighted how the presence of the materials stimulated a change in the morphology of the cells into a polygonal shape, surface reactions with the thickening of the membrane, and expression of actin. In particular, the morphological changes were appreciable from T1, with a progressive increase in the considered morphological characteristics at T2 and T3 follow-ups. The proliferation assay showed a statistical significance between the different experimental materials and the negative control in T2 and T3 follow-ups. The post hoc analysis did not reveal any differences between the materials. In conclusion, the grafts obtained with the low-temperature extractions protocol and not exposed to NaOH solution showed positive morphological reactions with no differences in the sizes of particles.


Assuntos
Fibroblastos , Ligamento Periodontal , Animais , Bovinos , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Minerais/metabolismo , Hidróxido de Sódio , Temperatura
15.
Medicina (Kaunas) ; 58(7)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35888585

RESUMO

Background and objectives: The purpose of the present systematic review was to analyze the effectiveness of erythritol-based air-polishing in non-surgical periodontal therapy. Materials and methods: The protocol details were registered in the PROSPERO database (CRD42021267261). This review was conducted under the PRISMA guidelines. The electronic search was performed in PubMed, Scopus, and Web of Science databases to find relevant clinical trials published until January 2022. The inclusion criteria consisted of human clinical trials which reported the use of non-surgical periodontal treatment and erythritol air-polishing compared to non-surgical periodontal treatment alone in patients with good systemic health requiring treatment for periodontal disease. Results: 810 studies were imported into the Covidence Platform. Of these, seven clinical trials met the inclusion criteria. In active periodontal therapy, for PD (probing depth), CAL (clinical attachment level), and BOP (bleeding on probing), no statistical significance was achieved at 6 months follow-up. In supportive periodontal therapy for PD, CAL, and BOP, no statistical significance was achieved at 3 months follow-up. Conclusions: The findings suggest that erythritol air-polishing powder did not determine superior improvements of periodontal parameters compared to other non-surgical periodontal therapies. Future randomized clinical trials (RCTs) with calibrated protocols for diagnosis, therapeutic approaches, and longer follow-up are needed to draw a clear conclusion about the efficiency of erythritol air-polishing powder.


Assuntos
Eritritol , Doenças Periodontais , Eritritol/uso terapêutico , Humanos , Doenças Periodontais/terapia , Pós , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Int J Mol Sci ; 22(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34445386

RESUMO

Understanding the biological and morphological reactions of human cells towards different dentinal derivate grafting materials is fundamental for choosing the type of dentin for specific clinical situations. This study aimed to evaluate human periodontal ligament fibroblasts (hPLF) cells exposed to different dentinal derivates particles. The study design included the in vitro evaluation of mineralized dentine (SG), deproteinized and demineralized dentine (DDP), and demineralized dentine (TT) as test materials and of deproteinized bovine bone (BIOS) as the positive control material. The materials were kept with the hPLF cell line, and the evaluations were made after 24 h, 72 h, and 7 days of in vitro culture. The evaluated outcomes were proliferation by using XTT assays, the morphological characteristics by light microscopy (LM) and by the use of scanning electron microscopy (SEM), and adhesion by using confocal microscopy (CLSM). Overall, the experimental materials induced a positive response of the hPLFs in terms of proliferation and adhesion. The XTT assay showed the TT, and the SG induced significant growth compared to the negative control at 7 days follow-up. The morphological data supported the XTT assay: the LM observations showed the presence of densely packed cells with a modified shape; the SEM observations allowed the assessment of how fibroblasts exposed to DDP and TT presented cytoplasmatic extensions; and SG and BIOS also presented the thickening of the cellular membrane. The CLMS observations showed the expression of the proliferative marker, as well as and the expression of cytoskeletal elements involved in the adhesion process. In particular, the vinculin and integrin signals were stronger at 72 h, while the actin signal remained constantly expressed in all the follow-up of the sample exposed to SG material. The integrin signal was stronger at 72 h, and the vinculin and actin signals were stronger at 7 days follow-up in the sample exposed to DDP material. The vinculin and integrin signals were stronger at 72 h follow-up in the sample exposed to TT material; vinculin and integrin signals appear stronger at 24 h follow-up in the sample exposed to BIOS material. These data confirmed how dentinal derivates present satisfying biocompatibility and high conductivity and inductivity properties fundamental in the regenerative processes. Furthermore, the knowledge of the effects of the dentin's degree of mineralization on cellular behavior will help clinicians choose the type of dentine derivates material according to the required clinical situation.


Assuntos
Biomarcadores/metabolismo , Substitutos Ósseos/farmacologia , Dentina/química , Ligamento Periodontal/citologia , Animais , Substitutos Ósseos/química , Bovinos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Integrinas/metabolismo , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Ligamento Periodontal/efeitos dos fármacos , Ligamento Periodontal/metabolismo , Vinculina/metabolismo
17.
Medicina (Kaunas) ; 57(2)2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562581

RESUMO

Background and Objectives: The aim of the present systematic review and meta-analysis was to investigate the efficacy of leukocyte-platelet-rich fibrin (L-PRF) in addition to coronally advanced flap (CAF) for the treatment of both single and multiple gingival recessions (GRs) compared to the CAF alone and to the adjunct of connective tissue graft (CTG). Root coverage outcomes using platelet concentrates have gained increased interest. In particular, it has been suggested that adding L-PRF to CAF may provide further benefits in the treatment of GRs. Materials and Methods: An electronic and manual literature search was conducted to identify randomized controlled trials (RTCs) investigating root coverage outcomes with CAF + L-PRF. The outcomes of interest included mean root coverage (mRC), recession reduction, keratinized tissue width (KTW) gain, gingival thickness (GT) gain, and patient-reported outcome measures (PROms) such as pain perception and discomfort. Results: A total of 275 patients and 611 surgical sites were analyzed. L-PRF in adjunct to single CAF seems to show statistically significant results regarding clinical attachment level (CAL) with a weighted means (WM) 0.43 95% CI (-0.04,0.91), p < 0.0001, GT (WM 0.17 95% CI (-0.02,0.36), p < 0.0001, and mRC (WM 13.95 95% CI (-1.99,29.88) p < 0.0001, compared to single CAF alone. Interesting results were obtained from the adjunct of PRF to multiple CAF with respect to multiple CAF alone with an increase in the mRC WM 0.07 95% CI (-30.22,30.35), p = 0.0001, and PPD change WM 0.26 95% CI (-0.06,0.58), p < 00001. On the other hand, no statistically significant data were obtained when L-PRF was added to single or multiple CAF combined with CTG according to the included outcomes such as mRC (p = 0.03 overall). Conclusions: L-PRF is a valid alternative to CAF alone. L-PRF compared to CTG in single and multiple CAF showed statistically significant results regarding pain perception and discomfort PROms (p < 0.0001). However, CTG remains the gold standard for treating gingival recession.


Assuntos
Retração Gengival , Fibrina Rica em Plaquetas , Tecido Conjuntivo , Retração Gengival/cirurgia , Humanos , Retalhos Cirúrgicos , Resultado do Tratamento
18.
Biophys J ; 118(1): 4-14, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31810660

RESUMO

The electrical membrane potential (Vm) is one of the components of the electrochemical potential of protons across the biological membrane (proton motive force), which powers many vital cellular processes. Because Vm also plays a role in signal transduction, measuring it is of great interest. Over the years, a variety of techniques have been developed for the purpose. In bacteria, given their small size, Nernstian membrane voltage probes are arguably the favorite strategy, and their cytoplasmic accumulation depends on Vm according to the Nernst equation. However, a careful calibration of Nernstian probes that takes into account the tradeoffs between the ease with which the signal from the dye is observed and the dyes' interactions with cellular physiology is rarely performed. Here, we use a mathematical model to understand such tradeoffs and apply the results to assess the applicability of the Thioflavin T dye as a Vm sensor in Escherichia coli. We identify the conditions in which the dye turns from a Vm probe into an actuator and, based on the model and experimental results, propose a general workflow for the characterization of Nernstian dye candidates.


Assuntos
Corantes/metabolismo , Fenômenos Eletrofisiológicos , Escherichia coli/fisiologia , Calibragem , Permeabilidade da Membrana Celular , Escherichia coli/citologia , Escherichia coli/metabolismo , Fluxo de Trabalho
19.
Biomacromolecules ; 20(3): 1375-1384, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30694655

RESUMO

The ability of peculiar iron oxide nanoparticles (IONPs) to evade the immune system was investigated in vivo. The nanomaterial was provided directly into the farming water of zebrafish ( Danio rerio) and the distribution of IONPs and the delivery of oxytetracycline (OTC) was studied evidencing the successful overcoming of the intestinal barrier and the specific and prolonged (28 days) organotropic delivery of OTC to the fish ovary. Noteworthy, no sign of adverse effects was observed. In fish blood, IONPs were able to specifically bind apolipoprotein A1 (Apo A1) and molecular modeling showed the structural analogy between the IONP@Apo A1 nanoconjugate and high-density lipoprotein (HDL). Thus, the preservation of the biological identity of the protein suggests a plausible explanation of the observed overcoming of the intestinal barrier, of the great biocompatibity of the nanomaterial, and of the prolonged drug delivery (benefiting of the lipoprotein transport route). The present study promises novel and unexpected stealth materials in nanomedicine.


Assuntos
Sistemas de Liberação de Medicamentos , Compostos Férricos/química , Nanopartículas Metálicas/química , Animais , Barreira Hematoencefálica , Cromatografia Líquida de Alta Pressão , Peixes , Espectrometria de Massas , Ligação Proteica
20.
Food Microbiol ; 66: 129-140, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28576361

RESUMO

This study used cell-free enzyme (CFE) extracts from Lactobacillus casei, Hafnia alvei, Debaryomyces hansenii and Saccharomyces cerevisiae to condition or accelerate Pecorino-type cheese ripening. Compositional, microbiological, and biochemical analyses were performed, and volatile and sensory profiles were obtained. Lactobacilli and cocci increased during ripening, especially in cheeses containing CFE from L. casei, H. alvei and D. hansenii (LHD-C) and L. casei, H. alvei and S. cerevisiae (LHS-C). Compared to control cheese (CC), several enzymatic activities were higher (P < 0.05) in CFE-supplemented cheeses. Compared to the CC (1907 mg kg-1 of cheese), the free amino acid level increased (P < 0.05) in CFE-supplemented cheeses, ranging from approximately 2575 (LHS-C) to 5720 (LHD-C) mg kg-1 of cheese after 60 days of CFE-supplemented ripening. As shown by GC/MS analysis, the levels of several volatile organic compounds were significantly (P < 0.05) lower in CC than in CFE-supplemented cheeses. All cheeses manufactured by adding multiple CFEs exhibited higher scores (P < 0.05) for internal structure, acid taste and juiciness than CC samples. This study shows the possibility of producing ewes' milk cheese with standardized characteristics and improved flavor intensity in a relatively short time.


Assuntos
Queijo/análise , Debaryomyces/enzimologia , Enzimas/química , Manipulação de Alimentos/métodos , Lacticaseibacillus casei/enzimologia , Leite/química , Saccharomyces cerevisiae/enzimologia , Animais , Biocatálise , Humanos , Ovinos , Paladar , Compostos Orgânicos Voláteis/análise
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