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1.
Int J Mol Sci ; 25(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39063086

RESUMO

Pyrogens are fever-inducing substances routinely investigated in health products through tests such as the Rabbit Pyrogen Test (RPT), the Limulus Amebocyte Lysate (LAL), and the Monocyte Activation Test (MAT). However, the applications of the MAT for medical devices and biomaterials remain limited. This work aimed to overview the studies evaluating the pyrogenicity of medical devices and biomaterials using the MAT, highlighting its successes and potential challenges. An electronic search was performed by December 2023 in PubMed, Scopus, and Web of Science, identifying 321 records which resulted in ten selected studies. Data were extracted detailing the tested materials, MAT variants, interferences, and comparisons between methods. Methodological quality was assessed using the ToxRTool, and the results were synthesized descriptively. The selected studies investigated various materials, including polymers, metals, and natural compounds, employing the different biological matrices of the MAT. Results showed the MAT's versatility, with successful detection of pyrogens in most materials tested, though variability in sensitivity was noted based on the material and testing conditions. Challenges remain in optimizing protocols for different material properties, such as determining the best methods for direct contact versus eluate testing and addressing the incubation conditions. In conclusion, the MAT demonstrates significant potential as a pyrogen detection method for medical devices and biomaterials. However, continued research is essential to address existing gaps, optimize protocols, and validate the test across a broader range of materials.


Assuntos
Materiais Biocompatíveis , Equipamentos e Provisões , Monócitos , Pirogênios , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Pirogênios/análise , Materiais Biocompatíveis/química , Humanos , Animais
2.
Clin Oral Implants Res ; 34(9): 920-933, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37345230

RESUMO

OBJECTIVES: The aim of the present human observational study is to provide morphologic and morphometric analysis of peri-implant connective tissue next to abutments with divergent or convergent macro-geometry and different surface micro-characteristics. MATERIALS AND METHODS: Thirty patients were rehabilitated with single implants in the posterior area and one out of three different healing abutments with a one-stage technique: machined divergent abutment (DIV-MAC), machined convergent abutment (CONV-MAC) or convergent abutment with ultrathin threaded surface (CONV-UTM). At 3 months postimplant insertion, peri-implant soft tissue was harvested; the following outcomes were investigated: histomorphometry (vertical width of connective and epithelial components) as detected by histology and polarized light; and connective tissue vertical width and 3D organization as detected by synchrotron-based high-resolution phase-contrast-based tomography (PhC-µCT). RESULTS: Significant differences in connective tissue vertical dimension (aJE-AM) were found between DIV-MAC and both CONV-MAC and CONV-UTM, both by histology and PhC-µCT, with significantly higher values for the last two groups. Moreover, 2D histological analysis did not find significant differences in the junctional epithelium vertical dimension (PM-aJE). Importantly, PhC-µCT analysis revealed, at 3D level, significant greater amount and density of collagen bundles for CONV-UTM compared with the other two groups. CONCLUSIONS: Convergent abutment profiles, regardless of their surface micro-geometry, seem to favor axial development of peri-implant connective tissue. Moreover, ultrathin threaded surfaces seem associated with denser and greater connective tissue organization, which might improve peri-implant soft tissue seal.


Assuntos
Implantes Dentários , Dente , Humanos , Tecido Conjuntivo/patologia , Colágeno , Inserção Epitelial , Dente Suporte , Titânio
3.
Clin Oral Investig ; 28(1): 28, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38147179

RESUMO

OBJECTIVES: This in vitro study is aimed at assessing whether implant primary stability is influenced by implant length in artificial bone with varying densities. MATERIALS AND METHODS: A total of 120 truncated-conical implants (60 long-length: 3p L, 3.8 × 14 mm; 60 short-length: 3p S, 3.8 × 8 mm) were inserted into 20, 30, and 40 pounds per cubic foot (PCF) density polyurethane blocks. The insertion torque (IT), removal torque (RT), and resonance frequency analysis (RFA) values were recorded for each experimental condition. RESULTS: In 30 and 40 PCF blocks, 3p S implants exhibited significantly higher IT values (90 and 80 Ncm, respectively) than 3p L (85 and 50 Ncm, respectively). Similarly, RT was significantly higher for 3p S implants in 30 and 40 PCF blocks (57 and 90 Ncm, respectively). However, there were no significant differences in RFA values, except for the 20 PCF block, where 3pS implants showed significantly lower values (63 ISQ) than 3p L implants (67 ISQ) in both the distal and mesial directions. CONCLUSIONS: These results demonstrated that the implant's length mainly influences the IT and RT values in the polyurethane blocks that mimic the mandibular region of the bone, resulting in higher values for the 3p S implants, while the RFA values remained unaffected. However, in the lowest density block simulating the maxillary bone, 3p L implants exhibited significantly higher ISQ values. CLINICAL RELEVANCE: Therefore, our data offer valuable insights into the biomechanical behavior of these implants, which could be clinically beneficial for enhancing surgical planning.


Assuntos
Implantes Dentários , Maxila , Poliuretanos , Análise de Frequência de Ressonância , Torque
5.
Int J Mol Sci ; 24(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37175457

RESUMO

The use of biomaterial for tissue repair involves the interaction between materials and cells, and the coagulum formation represents the first step of tissue healing. This process is particularly critical in the oral cavity, where the wounds are immediately subjected to the masticatory mechanical stress, saliva invasion, and bacterial attack. Therefore, the present study aimed to explore the structural features and the biological activities of a hemostatic collagen sponge on human gingival fibroblasts (HGFs) and human oral osteoblasts (HOBs). The microstructure of the collagen sponge was characterized by a scanning electron microscope (SEM) and histological analysis. The porosity was also calculated. To investigate biological activities, HGFs and HOBs were cultured on the collagen sponges, and their adhesion was observed at SEM on the third day, while cell viability was investigated at the third and seventh days by Tetrazolium (MTT) assay. For osteoblasts seeded on collagen sponge the mineralization ability was also evaluated by alkaline phosphatase (ALP) assay at the seventh day, and by Alizarin red staining on the 14th. Furthermore, the gene expression of ALP and osteocalcin (OCN) was investigated after 3, 7 and 14 days. SEM images of the sponge without cells showed a highly porous 3D structure, confirmed by the measurement of porosity that was more than 90%. The samples cultured were characterized by cells uniformly distributed and adhered to the sponge surface. Proliferation ended up being promoted, as well as the mineralization ability of the osteoblasts, mainly at the mature stage. In conclusion, this collagen sponge could have a potential use for tissue healing.


Assuntos
Hemostáticos , Humanos , Porosidade , Hemostáticos/farmacologia , Diferenciação Celular , Proliferação de Células , Colágeno/química , Osteoblastos , Fibroblastos , Células Cultivadas
6.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36834684

RESUMO

Recently, there has been an increasing interest in finding new approaches to manage oral wound healing. Although resveratrol (RSV) exhibited many biological properties, such as antioxidant and anti-inflammatory activities, its use as a drug is limited by unfavorable bioavailability. This study aimed to investigate a series of RSV derivatives (1a-j) with better pharmacokinetic profiles. At first, their cytocompatibility at different concentrations was tested on gingival fibroblasts (HGFs). Among them, derivatives 1d and 1h significantly increased cell viability compared to the reference compound RSV. Thus, 1d and 1h were investigated for cytotoxicity, proliferation, and gene expression in HGFs, endothelial cells (HUVECs), and oral osteoblasts (HOBs), which are the main cells involved in oral wound healing. For HUVECs and HGFs, the morphology was also evaluated, while for HOBs ALP and mineralization were observed. The results showed that both 1d and 1h did not exert negative effects on cell viability, and at a lower concentration (5 µM) both even significantly enhanced the proliferative rate, compared to RSV. The morphology observations pointed out that the density of HUVECs and HGFs was promoted by 1d and 1h (5 µM) and mineralization was promoted in HOBs. Moreover, 1d and 1h (5 µM) induced a higher eNOS mRNA level in HUVECs, higher COL1 mRNA in HGFs, and higher OCN in HOBs, compared to RSV. The appreciable physicochemical properties and good enzymatic and chemical stability of 1d and 1h, along with their promising biological properties, provide the scientific basis for further studies leading to the development of RSV-based agents useful in oral tissue repair.


Assuntos
Células Endoteliais , Fibroblastos , Resveratrol/farmacologia , Células Cultivadas , Fibroblastos/metabolismo , Cicatrização , RNA Mensageiro/metabolismo
7.
Periodontol 2000 ; 90(1): 62-87, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36183328

RESUMO

In recent years, the practice of dentistry and periodontology has become complicated by several risk factors, including the treatment of an increasing number of patients with substance use disorder. This review presents an update in the current literature of the impact of illegal drug use on periodontal conditions and their possible effect as risk factors or indicators. The main illegal drugs that may have an impact on periodontal health and conditions are described, including their effect, medical manifestations, risks, and the overall effect on oral health and on the periodontium. Where available, data from epidemiologic studies are analyzed and summarized. The clinical management of periodontal patients using illegal drugs is reported in a comprehensive approach inclusive of the detection of illicit drug users, screening, interviewing and counseling, the referral to treatment, and the dental and periodontal management. With regard to the impact of illegal substance use on periodontal conditions, there is moderate evidence that regular long-term use of cannabis is a risk factor for periodontal disease, manifesting as a loss of periodontal attachment, deep pockets, recessions, and gingival enlargements. Limited evidence also shows that the use of cocaine can cause a series of gingival conditions that mostly presents as chemical induced-traumatic lesions (application of cocaine on the gingiva) or necrotizing ulcerative lesions. There is a scarcity of data regarding the impact of other drug use on periodontal health. There is evidence to suggest that regular long-term use of cannabis is a risk factor for periodontal disease and that the use of cocaine can cause a series of periodontal conditions. The dental treatment of subjects that use illegal substances is becoming more common in the daily clinical practice of periodontists and other dental clinicians. When the clinicians encounter such patients, it is essential to manage their addiction properly taking into consideration the impact of it on comprehensive dental treatment. Further studies and clinical observations are required to obtain sound and definitive information.


Assuntos
Cannabis , Cocaína , Alucinógenos , Drogas Ilícitas , Doenças Periodontais , Gengiva , Humanos , Drogas Ilícitas/efeitos adversos , Doenças Periodontais/terapia , Periodonto
8.
Lasers Med Sci ; 37(9): 3671-3679, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36192667

RESUMO

This study aimed to evaluate the effects of a new photodynamic protocol (ALAD-PDT) on primary human osteoblasts (hOBs). The ALAD-PDT protocol consists of a heat-sensitive gel with 5% 5-delta aminolevulinic acid commercialized as Aladent (ALAD), combined with 630 nm LED. For this purpose, the hOBs, explanted from human mandible bone fragments, were used and treated with different ALAD concentrations (10%, 50%, 100% v/v) incubated for 45 min and immediately afterwards irradiated with a 630 nm LED device for 7 min. The untreated and unirradiated cells were considered control (CTRL). The cellular accumulation of the photosensitizer protoporphyrin IX (PpIX), the proliferation, the alkaline phosphatase (ALP) activity, and the calcium deposition were assessed. All concentrations (10, 50, 100%) determined a significant increment of PpIX immediately after 45 min of incubation (0 h) with the highest peak by ALAD (100%). The consequent 7 min of light irradiation caused a slight decrease in PpIX. At 48 h and 72 h, any increment of PpIX was observed. The concentration 100% associated with LED significantly increased hOB proliferation at 48 h (+ 46.83%) and 72 h (+ 127.75%). The 50% and 100% concentrations in combination to the red light also stimulated the ALP activity, + 12.910% and + 14.014% respectively. The concentration 100% with and without LED was selected for the assessment of calcium deposition. After LED irradiation, a significant increase in calcium deposition was observed and quantified (+ 72.33%). In conclusion, the ALAD-PDT enhanced proliferation, the ALP activity, and mineralized deposition of human oral osteoblasts, highlighting a promising potential for bone tissue regeneration.


Assuntos
Ácido Aminolevulínico , Fotoquimioterapia , Humanos , Ácido Aminolevulínico/farmacologia , Fotoquimioterapia/métodos , Cálcio , Protoporfirinas , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Osteoblastos
9.
Int J Mol Sci ; 23(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35457017

RESUMO

Regenerative medicine has constantly increased its field of influence over the last few years [...].


Assuntos
Materiais Biocompatíveis , Medicina Regenerativa , Células-Tronco , Engenharia Tecidual
10.
Int J Mol Sci ; 23(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35955456

RESUMO

A complex balanced equilibrium of the bacterial ecosystems exists in the oral cavity that can be altered by tobacco smoking, psychological stressors, bad dietary habit, and chronic periodontitis. Oral dysbiosis can promote the onset and progression of oral squamous cell carcinoma (OSCC) through the release of toxins and bacterial metabolites, stimulating local and systemic inflammation, and altering the host immune response. During the process of carcinogenesis, the composition of the bacterial community changes qualitatively and quantitatively. Bacterial profiles are characterized by targeted sequencing of the 16S rRNA gene in tissue and saliva samples in patients with OSCC. Capnocytophaga gingivalis, Prevotella melaninogenica, Streptococcus mitis, Fusobacterium periodonticum, Prevotella tannerae, and Prevotella intermedia are the significantly increased bacteria in salivary samples. These have a potential diagnostic application to predict oral cancer through noninvasive salivary screenings. Oral lactic acid bacteria, which are commonly used as probiotic therapy against various disorders, are valuable adjuvants to improve the response to OSCC therapy.


Assuntos
Carcinoma de Células Escamosas , Microbiota , Neoplasias Bucais , Bactérias/genética , Carcinoma de Células Escamosas/etiologia , Humanos , Microbiota/genética , Neoplasias Bucais/etiologia , Neoplasias Bucais/genética , RNA Ribossômico 16S/genética
11.
Clin Oral Investig ; 25(12): 6633-6642, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33893556

RESUMO

OBJECTIVE: Treatment of implants with peri-implantitis is often unsuccessful due to residual microbial biofilm hindering re-osseointegration. The aim of this study was to treat biofilm-grown titanium (Ti) implants with different modalities involving air abrasion (AA) and cold atmospheric plasma (CAP) to compare the effectiveness in surface decontamination and the alteration/preservation of surface topography. MATERIALS AND METHODS: Saliva collected from a peri-implantitis patient was used to in vitro develop human biofilm over 35 implants with moderately rough surface. The implants were then mounted onto standardized acrylic blocks simulating peri-implantitis defects and treated with AA (erythritol powder), CAP in a liquid medium, or a combination (COM) of both modalities. The remaining biofilm was measured by crystal violet (CV). Surface features and roughness before and after treatment were assessed by scanning electron microscope (SEM). The data were statistically analyzed using Kruskal-Wallis followed by Tukey's multiple comparison test. RESULTS: In the present peri-implantitis model, the human complex biofilm growth was successful as indicated by the statistical significance between the negative and positive controls. All the treatment groups resulted in a remarkable implant surface decontamination, with values very close to the negative control for AA and COM. Indeed, statistically significant differences in the comparison between the positive control vs. all the treatment groups were found. SEM analysis showed no post-treatment alterations on the implant surface in all the groups. CONCLUSIONS: Decontamination with AA delivering erythritol with or without CAP in liquid medium demonstrated compelling efficacy in the removal of biofilm from implants. All the tested treatments did not cause qualitative alterations to the Ti surface features. No specific effects of the CAP were observed, although further studies are necessary to assess its potential as monotherapy with different settings or in combination with other decontamination procedures. CLINICAL RELEVANCE: CAP is a promising option in the treatment of peri-implantitis because it has potential to improve the elimination of bacterial plaque from implant surfaces, in inaccessible pockets or during open-flap debridement, and should stimulate the process of the re-osseointegration of affected dental implants by not altering surface features and roughness.


Assuntos
Implantes Dentários , Peri-Implantite , Gases em Plasma , Abrasão Dental por Ar , Biofilmes , Humanos , Peri-Implantite/terapia , Propriedades de Superfície , Titânio
12.
Clin Oral Investig ; 25(5): 3297-3303, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33150510

RESUMO

OBJECTIVES: This animal study was conducted to evaluate the osteocyte index in the peri-implant bone around immediately restored implants under static lateral overload. MATERIAL AND METHODS: Seven mongrel dogs received three implants on each side of the mandible. Forty-two implants were distributed into three groups (14 implants per group); each animal received two implants connected to a 4.5-mm opened expansion device (experimental group); in the other mandible side, two implants were connected into an expansion device without activation (control group); one implant each side of the mandible was left submerged (unload group). After 4 months under daily mechanical and chemical plaque control, the animals were euthanized; dental implants and surrounding bone were removed and processed to obtain thin ground sections. Histomorphometry was used to evaluate the osteocyte index in the peri-implant bone contact to implant. RESULTS: A higher, statistically significant mean number of osteocytes × 10-5 µm2 (54.74 ± 23.91) was found in the control group compared with the test group (22.57 ± 22.55) (p = 0.0221). The correlation between percentage of bone-implant contact and osteocyte index for submerged implants was not statistically significant (p = 0.2667), whereas the value for immediately loaded implants was statistically significant (p = 0.0480). CONCLUSION: The lower number of osteocytes in the peri-implant bone around overloaded implants could be related to the need for functional adaptation of the bone tissue to overloading and to the hypothesized involvement of the osteocytes in the maintenance of the bone matrix in the control group. CLINICAL RELEVANCE: Osteocytes play a pivotal role in bone adaptation to mechanical loading, and the osteocyte network has been regarded as being the main mechanosensory mechanism.


Assuntos
Implantes Dentários , Placa Dentária , Animais , Implantação Dentária Endóssea , Cães , Mandíbula/cirurgia , Osseointegração , Osteócitos
13.
Clin Oral Investig ; 25(6): 3441-3451, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33155065

RESUMO

OBJECTIVES: The aim of the present study was to investigate whether peri-implant clinical parameters (modified plaque index (mPI), bleeding and/or suppuration on probing (B/SOP)) and local factors (type of prostheses, screw emergence, platform diameter, and abutment angulation) might contribute to the development of additional bone loss and peri-implantitis around dental implants. MATERIALS AND METHODS: Two hundred seventy-seven external hex connection implants placed in the posterior maxilla of 124 patients were retrospectively evaluated. They were divided into two groups: physiologic bone loss < 2 mm (PBL) or additional bone loss ≥ 2 mm (ABL). GEE logistic regression was applied to evaluate the influence of type of prostheses (implant-supported single crown (ISSC), fixed partial denture (ISFPD), and full denture (ISFD)) and clinical parameters (mPI and S/BOP) on bone loss. RESULTS: Among the 277 implants, 159 (57.4%) presented PBL and 118 (42.6%) presented ABL. Within the ABL group, 20.6% implants were diagnosed with peri-implantitis. mPI significantly correlated with the type of prosthesis and the highest value of mPI (index = 3) was observed in ISFD (23.8%). Moreover, peri-implantitis was more frequently associated with ISFD (32.79%) than ISSC and ISFDP (13.79% and 13.48, respectively) CONCLUSIONS: ISFD in the posterior maxilla presented high rates of ABL and showed a higher prevalence of peri-implantitis. None of the local factors seemed to contribute to the development of these conditions. Further investigations are needed to prospectively support the results of the present study. CLINICAL RELEVANCE: Patients rehabilitated with ISFD should be carefully monitored and have more frequent maintenance visits to prevent or control peri-implant bone loss.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Peri-Implantite , Perda do Osso Alveolar/diagnóstico por imagem , Implantes Dentários/efeitos adversos , Prótese Dentária Fixada por Implante , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Análise Multivariada , Peri-Implantite/diagnóstico por imagem , Estudos Retrospectivos
14.
Int J Mol Sci ; 22(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34576038

RESUMO

Current research on dental implants has mainly focused on the influence of surface roughness on the rate of osseointegration, while studies on the development of surfaces to also improve the interaction of peri-implant soft tissues are lacking. To this end, the first purpose of this study was to evaluate the response of human gingival fibroblasts (hGDFs) to titanium implant discs (Implacil De Bortoli, Brazil) having different micro and nano-topography: machined (Ti-M) versus sandblasted/double-etched (Ti-S). The secondary aim was to investigate the effect of the macrogeometry of the discs on cells: linear-like (Ti-L) versus wave-like (Ti-W) surfaces. The atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis showed that the Ti-S surfaces were characterized by a significantly higher micro and nano roughness and showed the 3D macrotopography of Ti-L and Ti-W surfaces. For in vitro analyses, the hGDFs were seeded into titanium discs and analyzed at 1, 3, and 5 days for adhesion and morphology (SEM) viability and proliferation (Cck-8 and MTT assays). The results showed that all tested surfaces were not cytotoxic for the hGDFs, rather the nano-micro and macro topography favored their proliferation in a time-dependent manner. Especially, at 3 and 5 days, the number of cells on Ti-L was higher than on other surfaces, including Ti-W surfaces. In conclusion, although further studies are needed, our in vitro data proved that the use of implant discs with Ti-S surfaces promotes the adhesion and proliferation of gingival fibroblasts, suggesting their use for in vivo applications.


Assuntos
Adesão Celular/efeitos dos fármacos , Implantes Dentários , Gengiva/efeitos dos fármacos , Osseointegração/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Gengiva/crescimento & desenvolvimento , Humanos , Teste de Materiais , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Propriedades de Superfície/efeitos dos fármacos , Titânio/química , Titânio/uso terapêutico
15.
J Mater Sci Mater Med ; 31(10): 84, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32989624

RESUMO

The aim of this study was to evaluate the interaction between Streptococcus oralis and Polyetheretherketone (PEEK), a novel material recently introduced in implantology. The topographical characterization and the Streptococcus oralis adhesion on this material were compared with other titanium surfaces, currently used for the production of dental implants: machined and double etched (DAE). The superficial micro-roughness of the PEEK discs was analyzed by scanning electron microscopy (SEM) and, the Energy Dispersive Spectrometer (EDS) analyzed their chemical composition. Atomic Force Microscopy (AFM) was used to characterize the micro-topography and the sessile method to evaluate the wettability of the samples. Microbiological analysis measured the colony forming units (CFUs), the biomass (OD570 detection) and the cell viability after 24 and 48 h after Streptococcus oralis cultivation on the different discs, that were previously incubated with saliva. Results showed that PEEK was characterized by a micro-roughness that was similar to machined titanium but at nano-level the nano-roughness was significantly higher in respect to the other samples. The EDS showed that PEEK superficial composition was characterized mainly by Carbonium and Oxygen. The hydrophilicity and wetting properties of PEEK were similar to machined titanium; on the contrary, double etched discs (DAE) samples were characterized by significantly higher levels (p < 0.05). PEEK was characterized by significant lower CFUs, biomass and viable cells in respect to the titanium surfaces. No differences were found between machined and DAE. The anti-adhesive and antibacterial properties showed by PEEK at 24 and 48 h against a pioneer such as S. oralis, could have an important role in the prevention of all pathologies connected with biofilm formation, like peri-implantitis in dentistry or prosthetic failures in orthopedics.


Assuntos
Benzofenonas/química , Implantes Dentários , Polímeros/química , Desenho de Prótese , Streptococcus oralis/metabolismo , Titânio/química , Antibacterianos/farmacologia , Aderência Bacteriana , Biomassa , Carbono/química , Sobrevivência Celular , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Teste de Materiais , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Oxigênio/química , Falha de Prótese , Saliva/microbiologia , Células-Tronco , Propriedades de Superfície , Molhabilidade
16.
Clin Oral Investig ; 24(8): 2543-2557, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32591868

RESUMO

OBJECTIVES: The aim of this systematic review and meta-analysis was to compare the use of platelet-rich fibrin (PRF) with other commonly utilized treatment modalities for root coverage procedures. MATERIALS AND METHODS: The eligibility criteria comprised randomized controlled trials (RCTs) comparing the performance of PRF with that of other modalities in the treatment of Miller class I or II (Cairo RT I) gingival recessions. Studies were classified into 5 categories as follows: (1) coronally advanced flap (CAF) alone vs CAF/PRF, (2) CAF/connective tissue graft (CAF/CTG) vs CAF/PRF, (3) CAF/enamel matrix derivative (CAF/EMD) vs CAF/PRF, (4) CAF/amnion membrane (CAF/AM) vs CAF/PRF, and (5) CAF/CTG vs CAF/CTG/PRF. Studies were evaluated for percentage of relative root coverage (rRC; primary outcome), clinical attachment level (CAL), keratinized mucosa width (KMW), and probing depth (PD) (secondary outcomes). RESULTS: From 976 articles identified, 17 RCTs were included. The use of PRF statistically significantly increased rRC and CAL compared with CAF alone. No change in KMW or reduction in PD was reported. Compared with PRF, CTG resulted in statistically significantly better KMW and RC. No statistically significant differences were reported between the CAF/PRF and CAF/EMD groups or between the CAF/PRF and CAF/AM groups for any of the investigated parameters. CONCLUSIONS: The use of CAF/PRF improved rRC and CAL compared with the use of CAF alone. While similar outcomes were observed between CAF/PRF and CAF/CTG for CAL and PD change, the latter group led to statistically significantly better outcomes in terms of rRC and KTW. In summary, the use of PRF in conjunction with CAF may represent a valid treatment modality for gingival recessions exhibiting adequate baseline KMW. CLINICAL RELEVANCE: The data indicate that the use of PRF in conjunction with CAF statistically significantly improves rRC when compared with CAF alone but did not improve KMW. Therefore, in cases with limited baseline KMW, the use of CTG may be preferred over PRF.


Assuntos
Retração Gengival , Tecido Conjuntivo , Gengiva , Humanos , Fibrina Rica em Plaquetas , Retalhos Cirúrgicos , Raiz Dentária , Resultado do Tratamento
17.
Int J Mol Sci ; 21(20)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066082

RESUMO

Nitric oxide (NO), a small gaseous and multifunctional signaling molecule, is involved in the maintenance of metabolic and cardiovascular homeostasis. It is endogenously produced in the vascular endothelium by specific enzymes known as NO synthases (NOSs). Subsequently, NO is readily oxidized to nitrite and nitrate. Nitrite is also derived from exogenous inorganic nitrate (NO3) contained in meat, vegetables, and drinking water, resulting in greater plasma NO2 concentration and major reduction in systemic blood pressure (BP). The recycling process of nitrate and nitrite to NO (nitrate-nitrite-NO pathway), known as the enterosalivary cycle of nitrate, is dependent upon oral commensal nitrate-reducing bacteria of the dorsal tongue. Veillonella, Actinomyces, Haemophilus, and Neisseria are the most copious among the nitrate-reducing bacteria. The use of chlorhexidine mouthwashes and tongue cleaning can mitigate the bacterial nitrate-related BP lowering effects. Imbalances in the oral reducing microbiota have been associated with a decrease of NO, promoting endothelial dysfunction, and increased cardiovascular risk. Although there is a relationship between periodontitis and hypertension (HT), the correlation between nitrate-reducing bacteria and HT has been poorly studied. Restoring the oral flora and NO activity by probiotics may be considered a potential therapeutic strategy to treat HT.


Assuntos
Pressão Sanguínea , Microbioma Gastrointestinal , Boca/microbiologia , Óxido Nítrico/metabolismo , Doenças Periodontais/microbiologia , Animais , Humanos , Boca/metabolismo , Doenças Periodontais/metabolismo , Doenças Periodontais/fisiopatologia
18.
Int J Mol Sci ; 21(21)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167597

RESUMO

This work aimed to compare the capability of Streptococcus oralis to adhere to a novel surface, double-etched titanium (DAE), in respect to machined and single-etched titanium. The secondary outcome was to establish which topographical features could affect the interaction between the implant surface and bacteria. The samples' superficial features were characterized using scanning electron microscopy (SEM) and energy dispersive x-ray spectrometry (EDS), and the wetting properties were tested through sessile methods. The novel surface, the double-etched titanium (DAE), was also analyzed with atomic force microscopy (AFM). S. oralis was inoculated on discs previously incubated in saliva, and then the colony-forming units (CFUs), biomass, and cellular viability were measured at 24 and 48h. SEM observation showed that DAE was characterized by higher porosity and Oxygen (%) in the superficial layer and the measurement of the wetting properties showed higher hydrophilicity. AFM confirmed the presence of a higher superficial nano-roughness. Microbiological analysis showed that DAE discs, coated by pellicle's proteins, were characterized by significantly lower CFUs at 24 and 48 h with respect to the other two groups. In particular, a significant inverse relationship was shown between the CFUs at 48 h and the values of the wetted area and a direct correlation with the water contact angle. The biomass at 24 h was slightly lower on DAE, but results were not significant concerning the other groups, both at 24 and 48 h. The DAE treatment not only modifies the superficial topography and increased hydrophilicity, but it also increases the Oxygen percentage in the superficial layer, which could contribute to the inhibition of S. oralis adhesion. DAE can be considered a promising treatment for titanium implants to counteract a colonization pioneer microorganism, such as S. oralis.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Implantes Dentários/microbiologia , Streptococcus oralis/metabolismo , Titânio/química , Adesivos/metabolismo , Bactérias/metabolismo , Aderência Bacteriana/fisiologia , Biofilmes/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Implantes Dentários/tendências , Humanos , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Varredura/métodos , Espectrometria por Raios X/métodos , Streptococcus oralis/patogenicidade , Propriedades de Superfície/efeitos dos fármacos
19.
J Mater Sci Mater Med ; 30(12): 136, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31802234

RESUMO

Many medical-related scientific discoveries arise from trial-error patterns where the processes involved must be refined and modified continuously before any product could be able to reach the final costumers. One of the elements affecting negatively these processes is the inaccuracy of two-dimension (2D) standard culture systems, carried over in plastic plates or similar, in replicating complex environments and patterns. Consequently, animal tests are required to validate every in vitro finding, at the expenses of more funds and ethical issues. A possible solution relies in the implementation of three-dimension (3D) culture systems as a fitting gear between the 2D tests and in vivo tests, aiming to reduce the negative in vivo outcomes. These 3D structures are depending from the comprehension of the extracellular matrix (ECM) and the ability to replicate it in vitro. In this article a comparison of efficacies between these two culture systems was taken as subject, human mesenchymal stem cells (hMSCs) was utilized and a hybrid scaffold made by a blend of chitosan, gelatin and biomineralized gelatin was used for the 3D culture system.


Assuntos
Técnicas de Cultura de Células , Células-Tronco Mesenquimais/fisiologia , Osteogênese/fisiologia , Alicerces Teciduais , Materiais Biocompatíveis , Diferenciação Celular , Humanos , Teste de Materiais
20.
J Craniofac Surg ; 30(4): 1055-1057, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30059423

RESUMO

BACKGROUND: The overall success and predictability of dental implant treatment hinge on the primary stability, direct bone-to implant contact formation, and quantity and/or quality of residual bone. Pulsed electromagnetic field has been reported to increase bone regeneration in various clinical situations. Therefore, it was hypothesized that devices which could locally generate a Pulsed electromagnetic field would stimulate bone healing and increase bone density surrounding implants. OBJECTIVE: To retrospectively assess the effects of the miniaturized electromagnetic device (MED) on the implants stability for the first time in human subjects, in a prospective case controlled series. METHODS: Twelve consecutive patients (28 implants) were included in the study.Twelve MED healing caps and 16 regular control healing caps were inserted. Resonance frequency analysis (RFA) was performed at implant placement and abutment connection and an implant stability quotient value was given for each implant. RESULTS: Twenty-eight dental implants were included in the current study. Maxillary implants stability was significantly higher with MED healing cups compared with controls at 15 days postimplantation (66.2 vs 62.1, P = .0008). Resonance frequency analysis test performed at 30 days postimplantation demonstrated significantly increased stability in MED as compared with the control 73.5 ±â€Š3.2 vs 66.7 ±â€Š4.8 in mandibular implants and 74 ±â€Š1.7 vs 65 ±â€Š2.3 in maxillary implants. At the 50 days postimplantation, RFA tests revealed markedly higher stability of the maxillary implants with MED active healing caps compared with nonactive 75.4 ±â€Š5.1 vs 68.5 ±â€Š8.5, respectively. CONCLUSIONS: We conclude that MED-abutment implants demonstrated a superior stability during the early phase of healing as compared with standard implants.


Assuntos
Implantes Dentários , Campos Eletromagnéticos , Magnetoterapia/instrumentação , Adulto , Idoso , Densidade Óssea , Regeneração Óssea , Dente Suporte , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Retenção em Prótese Dentária , Falha de Restauração Dentária , Feminino , Humanos , Pessoa de Meia-Idade , Análise de Frequência de Ressonância , Estudos Retrospectivos
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