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1.
J Clin Med ; 13(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38999234

RESUMO

Background: An accurate determination of the biological width and the relationship of the cemento-enamel junction with the border of the alveolar bone is crucial during a clinical crown-lengthening (CCL) procedure. The aim of this study was to present a technical note about the retraction techniques in cone beam computed tomography (CBCT) prior to CCL, highlighting the significant enhancement in procedural accuracy and predictability that these techniques offer. Methods: Clinical and radiological examinations should be performed before a CCL procedure. It is necessary to determine the length of the tooth crowns, the periodontal pockets' depth, and the phenotype of the gingiva. The ideal CBCT examination should be performed with soft tissue retraction. This can be achieved using retractors or cotton rolls. Results: Retraction of the lips, cheeks, and tongue allows one to assess the marginal gingiva, the cemento-enamel junction, and the alveolar bone. A detailed plan of the CCL procedure, which involves retraction, ensures both the aesthetic appeal and the achievement of a newly defined gingival zenith, enhancing the overall visual harmony. Conclusions: Compared with conventional radiographic imaging, the soft tissue retraction maneuver in CBCT prior to CCL surgery offers an effective approach to the evaluation and diagnosis of soft and hard tissue. This is because of the detailed planning of the aesthetic CCL procedure. Such an approach leads to superior aesthetic outcomes in dentistry, contributing to the advancement of aesthetic dentistry through a harmonious blend of art and science.

2.
J Clin Med ; 13(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38999468

RESUMO

Background: Tooth infraocclusion is a process in which a completely or partially erupted tooth gradually moves away from the occlusal plane. Submerged teeth can lead to serious complications. Treating teeth with infraocclusion is very challenging. One of the procedures allowing for the replacement of a missing tooth is autotransplantation. The aim of this paper is to review the literature on teeth autotransplantation, supported by a case report involving the autotransplantation of a third mandibular molar into the site of an extracted infraoccluded first mandibular molar, as well as the utilization of advanced platelet-rich fibrin (A-PRF) alongside autogenous dentin grafts for bone tissue regeneration. Methods: A severely infraoccluded first permanent right mandibular molar was extracted and then ground to obtain the dentin graft. A-PRF clots (collected from the patient's peripheral blood) were added to the autogenous dentin graft, to create the A-PRF membrane. An atraumatic extraction of the lower left third molar was performed and then it was transplanted into the socket of tooth no. 46. Immediately after transplantation, tooth no. 38 was stabilized with orthodontic bracket splints for 3 months. The patient attended regular follow-up visits within 12 months. Results: After one year, the patient did not report any pain. In the clinical examination, the tooth and surrounding tissues did not show any signs of infection. However, radiographically, cervical inflammatory resorption, unchanged pulp canal dimensions, absent root growth, periapical radiolucency, and lack of apical and marginal healing were observed. Reconstruction of the bone defect was obtained and the alveolar ridge of the mandible was preserved. Due to poor stability of the tooth and severe resorption, the tooth needed to be extracted. Conclusions: This study is designed to critically evaluate the efficacy of autotransplantation, the application of growth factors, and the integration of autogenous dentin grafts in remedying dental deficiencies resulting from reinclusion. We aim to point out the possible causes of treatment failure.

3.
Int J Mol Sci ; 25(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38673924

RESUMO

Chronic odontogenic maxillary sinusitis (COMS), a prolonged inflammation of the maxillary sinus lasting over 12 weeks, is often a result of periapical lesions, marginal periodontitis, and complications like oro-antral communication (OAC) and fistula (OAF). OAC, commonly emerging post-teeth extraction in the lateral maxilla, lacks documented treatments using advanced platelet-rich fibrin (A-PRF). This study evaluates A-PRF's efficacy in treating COMS and immediately sealing extensive OAC. A case of a 28-year-old male with COMS linked to a periapical lesion and supernumerary molars is presented. Treatment involved extracting specific teeth while preserving adjacent ones and using A-PRF for immediate OAC closure. A-PRF, enriched with growth factors, was pivotal in healing, showcasing enhanced tissue regeneration, pain reduction, and faster recovery. The findings suggest A-PRF as an effective adjunct in treating extensive OAC and COMS, proposing its inclusion in standard treatment protocols. This study underscores A-PRF's potential in improving outcomes for patients with COMS and related complications.


Assuntos
Sinusite Maxilar , Fibrina Rica em Plaquetas , Humanos , Fibrina Rica em Plaquetas/metabolismo , Masculino , Adulto , Sinusite Maxilar/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Extração Dentária , Seio Maxilar/cirurgia , Fístula Bucoantral/cirurgia
4.
Medicina (Kaunas) ; 60(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38541149

RESUMO

The gradual movement of a tooth away from the occlusal plane is called infraocclusion or reinclusion. Reincluded teeth are most often deciduous molars, and permanent teeth are less frequently affected. Depending on the level of the infraocclusion, the severity of the disorder is classified as mild, moderate, or severe. The etiology of the phenomenon is not fully known. Tooth submerging can lead to serious complications, such as abnormal position of adjacent teeth, displacement of the bud of the permanent successor, shortening of the dental arch, or developmental disturbances of alveolar process. Early diagnosis of the tooth infraocclusion and regular monitoring of its progression help to avoid serious permanent sequelae. The treatment of reinclusion often involves only observation. However, in some cases, the therapeutic procedure requires interdisciplinary treatment by specialists from various fields of dentistry. This study presents current methods of diagnosis and treatment of patients with submerged teeth.


Assuntos
Dentição Permanente , Má Oclusão , Humanos , Dente Decíduo , Má Oclusão/diagnóstico , Má Oclusão/etiologia , Má Oclusão/terapia , Extração Dentária/efeitos adversos , Mandíbula , Erupção Dentária
5.
Molecules ; 29(3)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38338434

RESUMO

2-ethylhexanol, an oxo alcohol competitively priced on the global market, has not been explored intensively as a raw material for surfactants, due to its weak hydrophobic character. However, its sequenced propoxylation and ethoxylation yield an innovative amphiphilic structure, which exhibits unique interfacial activity. The paper presents the differences in the fractional composition of innovative surfactants derived from 2-EH alcohol prepared using alkali and dimetalcyanide catalysts, as well as examples of excellent adsorption and interfacial properties of the latter. The adsorption behavior of the synthesized compounds was explored using equilibrium surface tension (the du Noüy ring method), dynamic surface tension (the maximum gas bubble pressure method) and static/dynamic contact angle (the sessile drop method). The results from the adsorption tests conducted at the air/aqueous surfactant solution interface underwent comprehensive qualitative and quantitative analyses. Moreover, based on the experimentally obtained dynamic surface tension isotherms and the developed algorithm, the diffusion coefficients for these preparations were estimated, and it was shown that the diffusivity of these surfactants is higher compared to the commercial formulations. The study's outcomes in the testing of wettability indicate that new synthesized nonionic and anionic surfactants constitute an interesting group of amphiphiles with a wide application potential as effective wetting agents, especially in relation to the polymer surface. It should therefore be emphasized that the innovative surfactants described in this article, derived from 2-EH alcohol and prepared using dimetalcyanide catalysts, can successfully compete with conventional preparations such as ABS (Dodecylbenzenesulfonic Acid) or AES (Alcohol Ethoxysulphate) acid salts.

6.
Medicina (Kaunas) ; 59(11)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38004081

RESUMO

Background: The risk of palatally displaced canines (PDCs) rises in patients with tooth agenesis. The orthodontic extrusion and alignment of PDCs require adequate anchorage to enable tooth movement and control the side effects. There is no paper presenting treatment in the case of severe oligodontia with simultaneous PDCs and the use of mini-implants (MIs) for their orthodontic extrusion. Case presentation: A 15-year-old patient presented with non-syndromic oligodontia and bilateral PDCs. Cone beam computed tomography revealed that both PDCs were in proximity to the upper incisors' roots. There was no evident external root resorption of the incisors. The "canines first" approach was chosen. MIs were used both as direct and indirect anchorage. First, the extrusive forces of cantilevers were directed both occlusally and distally. Next, the buccal directions of forces were implemented. Finally, fixed appliances were used. PDCs were extruded, aligned, and torqued. Proper alignment and occlusion were achieved to enable further prosthodontic restorations. Conclusions: The use of MIs made it possible to avoid collateral effects, reduce the risk of complications, and treat the patient effectively. MIs provide adequate anchorage in demanding cases. The use of MIs for the extrusion of PDCs made it possible to offer this treatment option to patients with severe oligodontia. The presented protocol was effective and served to circumvent treatment limitations associated with an inadequate amount of dental anchorage and a high risk of root resorption.


Assuntos
Reabsorção da Raiz , Dente Impactado , Humanos , Adolescente , Reabsorção da Raiz/terapia , Reabsorção da Raiz/etiologia , Dente Canino/cirurgia , Dente Impactado/cirurgia , Dente Impactado/complicações , Incisivo , Maxila
7.
Biomedicines ; 11(9)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37760830

RESUMO

There is no unequivocal scientific consensus for the temporary anchorage device (TAD) positioning in the infrazygomatic crest area (IZC). The two principal aims of this systematic review were to assess bone availability in the IZC and to establish both the target site and the need for cone-beam computed tomography (CBCT) prior to miniscrew placement. The study was performed following PRISMA guidelines (PROSPERO: CRD42023411650). The inclusion criteria were: at least 10 patients, three-dimensional radiological examination, and IZC assessment for the TAD placement. ROBINS-I tool and Newcastle-Ottawa Scale were used for quality evaluation. No funding was obtained. The study was based on the information coming from: PubMed, Google Scholar, Web of Science Core Collection, MDPI, Wiley, and Cochrane Libraries. The last search was carried out on 1 August 2023. Fourteen studies were identified for analysis. A narrative synthesis was performed to synthesize the findings of the different studies. Unfortunately, it is not possible to establish the generally recommended target site for IZC TAD placement. The reasons for this are the following: heterogeneity of available studies, inconsistent results, and significant risk of bias. The high variability of bone measurements and the lack of reliable predictors of bone availability justify the use of CBCT for TAD trajectory planning. There is a need for more high-quality studies aiming three-dimensional bone analysis of the IZC.

8.
Materials (Basel) ; 14(21)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34771758

RESUMO

The thermal and moisture properties of building envelope materials determine their performance over many years of use. Moisture has a particularly negative impact, impairing all the technical parameters and adversely affecting the microclimatic conditions inside the building. This article presents research and analysis on the moisture behavior of partitions made of autoclaved aerated concrete. Autoclaved aerated concrete is a very popular material for building external walls because of its relatively good thermal insulation and sufficient strength, if it is not subjected to increased moisture. This study investigated how the moisture content of this material changes with the change in relative air humidity. The four most popular density classes were studied. The sorption isotherms were determined by the static gravimetric method throughout the whole hygroscopic range. Moreover, the applicability of various models to describe sorption isotherms of this material group has been extensively evaluated. The tested models (Peleg, Redlich, Chen, Oswin, Henderson, Lewicki, Caurie, and GAB) all provided a very good fit with the experimental results for the tested material group (R2 ranged from 0.9599 to 0.9978). This paper indicates that the use of two additional approximation parameters (SSE and RMSE) allows a more precise assessment of the quality of individual models.

9.
J Orofac Orthop ; 82(3): 198-208, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33544175

RESUMO

PURPOSE: The aims of this retrospective cross-sectional study were to measure and compare labial and palatal alveolar bone heights of maxillary central incisors in unilateral cleft lip and palate patients, following STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines. PATIENTS AND METHODS: The study group consisted of 21 patients with a mean age of 16 years. High-resolution cone-beam computed tomography was performed at least one year after secondary alveolar bone grafting. The experimental side was the cleft side and the contralateral side without congenital cleft was the control. Measurements were performed on incisors' midsagittal cross-sections. The Wilcoxon signed-rank test was used for intergroup comparisons. RESULTS: The labial and palatal distances between alveolar bone crests and cementoenamel junctions were significantly greater on the cleft side than on the noncleft side. Mean differences were 0.75 and 1.41 mm, respectively. The prevalence of dehiscences at the cleft side maxillary central incisors was 52% on the labial surface and 43% on the palatal surface. In the controls, it was 19% and 14%, respectively. CONCLUSION: The cleft-adjacent maxillary central incisors had more apically displaced alveolar bone crests on the labial and palatal sides of the roots than the controls. Higher prevalence of dehiscences was found on the cleft side. Bone margin differences predispose to gingival height differences of the central incisors. These differences could increase the demands of patients to obtain more esthetic treatment results with orthodontic extrusion and periodontal intervention on the cleft side.


Assuntos
Fenda Labial , Fissura Palatina , Adolescente , Fenda Labial/diagnóstico por imagem , Fenda Labial/epidemiologia , Fissura Palatina/diagnóstico por imagem , Fissura Palatina/epidemiologia , Fissura Palatina/cirurgia , Tomografia Computadorizada de Feixe Cônico , Estudos Transversais , Estética Dentária , Humanos , Incisivo/diagnóstico por imagem , Maxila/diagnóstico por imagem , Estudos Retrospectivos
11.
Clin Oral Investig ; 25(4): 1967-1975, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32803441

RESUMO

OBJECTIVES: This retrospective cross-sectional study aimed to present a new method for secondary alveolar bone grafting (SABG) assessment and to qualitatively evaluate the SABG results in unilateral cleft lip and palate patients. MATERIALS AND METHODS: Research was conducted according to the STROBE guidelines. The study group consisted of 21 patients with a mean age of 16 years. High-resolution cone-beam computed tomography (CBCT) was performed at least 1 year after grafting. The experimental side was the cleft side, and the contralateral side without a congenital cleft was the control. Measurements were performed at four levels of the maxillary central incisors' roots according to the new scale with scores from 0 to 3. The sum of the scores provided a general assessment of bone architecture. The Wilcoxon signed-rank test was used for intergroup comparisons, and a Kappa coefficient was used for reproducibility measurements. RESULTS: High individual variability was found, and the bone architecture was significantly worse on the cleft side than on the noncleft side. The results showed 28.57% failure, 33.33% poor, 19.05% moderate, and 19.05% good results from the surgical procedure. Kappa coefficients produced results from 0.92 to 1.00 for intra-rater and from 0.81 to 1.00 for inter-rater reproducibility. CONCLUSIONS: CBCT provides detailed information about alveolar bone morphology. The new assessment method is useful at every treatment stage and provides excellent repeatability. SABG did not provide good bone morphology, in most cases. CLINICAL RELEVANCE: This research presents a new universal alternative for the assessment of SABG by utilizing CBCT.


Assuntos
Enxerto de Osso Alveolar , Fenda Labial , Fissura Palatina , Adolescente , Fenda Labial/diagnóstico por imagem , Fenda Labial/cirurgia , Fissura Palatina/diagnóstico por imagem , Fissura Palatina/cirurgia , Tomografia Computadorizada de Feixe Cônico , Estudos Transversais , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos
12.
J Craniomaxillofac Surg ; 47(4): 578-585, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30733132

RESUMO

INTRODUCTION: The development of 3D X-ray diagnostics has led to new methods for secondary alveolar bone grafting (SABG) assessment. The aim of this study was to collect and present literature from the years 2007-2018, and review on the current treatment outcome assessment methods for SABG. MATERIALS AND METHODS: A systematic review of literature from 2007 to 2018 was carried out, following PRISMA guidelines. 426 records were identified after duplicate references had been removed. 25 articles were included in the review. The Cochrane Collaboration tool or the methodological index for non-randomized studies was used for quality evaluation. RESULTS: Computed tomography and cone beam computed tomography were preferentially used for SABG treatment outcome verification. There were different assessment protocols. Due to the ways in which results were presented, methods were divided into five groups: linear measurements, volumetric measurements, density measurements, percentage ratios, and scales. There was only one randomized, controlled trial with high methodological quality. CONCLUSIONS: 1. Currently, 3D X-ray imaging is a standard treatment outcome verification method for SABG. 2. It is necessary to establish the required postoperative follow-up time for best SABG treatment outcome assessment. More prospective studies to assess bone graft outcomes after 6 months and 1 year are required.


Assuntos
Enxerto de Osso Alveolar , Fenda Labial , Fissura Palatina , Processo Alveolar , Fenda Labial/cirurgia , Tomografia Computadorizada de Feixe Cônico , Humanos , Resultado do Tratamento
13.
Ultrason Sonochem ; 48: 249-258, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30080548

RESUMO

The aim of these studies was to investigate the influence of airborne ultrasound-assisted convective drying and microwave-assisted convective drying, as well as their combination, on process kinetics, total color change, water activity, content of carotenoids, polyphenols and antioxidant activity of carrots (Daucus carota L.). The global model of drying kinetics based on coupled ordinary differential equations was used to describe the moisture and material temperature profiles during drying. Application of ultrasound and microwave in convective drying reduced drying time in the range of 9-81%, but the shortest drying time was observed for simultaneous action of convection, ultrasound and microwave. The results of qualitative analysis showed a product improvement due to ultrasound as compared to convective drying and microwave-convective drying. The proposed mathematical model of drying kinetics successfully simulated real drying processes. The proposed mathematical model of drying kinetics successfully simulated real hybrid drying processes.


Assuntos
Daucus carota/química , Daucus carota/normas , Conservação de Alimentos/métodos , Micro-Ondas , Controle de Qualidade , Ondas Ultrassônicas , Antioxidantes/análise , Carotenoides/análise , Cor , Conservação de Alimentos/normas , Cinética , Polifenóis/análise , Água
14.
Ultrason Sonochem ; 34: 531-539, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27773279

RESUMO

The effectiveness of hybrid drying based on convective drying with application of ultrasound and microwave enhancement is the main subject of the studies. The drying kinetics, energy consumption as well as the quality aspect of green pepper is analysed. It was shown that hybrid drying methods shorten significantly the drying time, reduce the energy consumption and affect positively the quality factors. Each of the analysed aspects depend on combination of the convective-ultrasound-microwave drying programs. Besides, based on the drying model elaborated earlier by one of the authors, the effects of ultrasound on convective drying assessed by such phenomena as "heating effect", "vibration effect" and "synergistic effect" are presented.


Assuntos
Ar , Capsicum/química , Convecção , Dessecação/métodos , Manipulação de Alimentos/métodos , Micro-Ondas , Ondas Ultrassônicas , Dessecação/instrumentação , Manipulação de Alimentos/instrumentação , Modelos Teóricos , Fatores de Tempo
15.
Nat Commun ; 5: 5521, 2014 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-25422853

RESUMO

The quest for new antimalarial drugs, especially those with novel modes of action, is essential in the face of emerging drug-resistant parasites. Here we describe a new chemical class of molecules, pyrazoleamides, with potent activity against human malaria parasites and showing remarkably rapid parasite clearance in an in vivo model. Investigations involving pyrazoleamide-resistant parasites, whole-genome sequencing and gene transfers reveal that mutations in two proteins, a calcium-dependent protein kinase (PfCDPK5) and a P-type cation-ATPase (PfATP4), are necessary to impart full resistance to these compounds. A pyrazoleamide compound causes a rapid disruption of Na(+) regulation in blood-stage Plasmodium falciparum parasites. Similar effect on Na(+) homeostasis was recently reported for spiroindolones, which are antimalarials of a chemical class quite distinct from pyrazoleamides. Our results reveal that disruption of Na(+) homeostasis in malaria parasites is a promising mode of antimalarial action mediated by at least two distinct chemical classes.


Assuntos
Amidas/farmacologia , Antimaláricos/farmacologia , Benzimidazóis/farmacologia , Eritrócitos/parasitologia , Malária/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Pirazóis/farmacologia , Sódio/metabolismo , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Feminino , Homeostase/efeitos dos fármacos , Humanos , Masculino , Plasmodium berghei/efeitos dos fármacos , Plasmodium berghei/genética , Plasmodium berghei/metabolismo , Plasmodium falciparum/enzimologia , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas de Protozoários
17.
J Pept Sci ; 14(11): 1163-72, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18646253

RESUMO

Further improvements related to the synthesis of peptides containing HmS are presented. Efficient synthetic protocols have been developed to synthesize "difficult" sequences containing a C-terminal HmS residue, MeA-HmS or consecutive HmS. Preparative methods for orthogonal N- and/or C-protected HmS(Ipr) derivatives are described. Their compatibility with standard solution or solid-phase peptide chemistry protocols allows synthetic flexibility toward HmS-containing peptides. In the synthesis of the sterically hindered dipeptides with the C-terminal HmS(Ipr) residue, HATU proves the highest efficiency, as compared with the fluoride and PyBroP/DMAP coupling methods. The HATU method also outperforms the fluoride activation in the solid-phase assembly of HmS homosequence. Specific protocols are described to overcome an undesired cyclization to diketopiperazines that occurs during the removal of Fmoc from dipeptides with the C-terminal HmS(Ipr) or HmS residues, thus precluding their C-->N elongation. The successful protocols involve: (i) the 2+1 condensation using mixed anhydride activation yielding the desired product with the highest optical integrity or (ii) use of the 2-chlorotrityl resin as a solid support sterically suppressing the undesired cleavage due to diketopiperazine formation. The latter approach allows the mild conditions of peptide cleavage from solid support, preserving the isopropylidene protection and minimizing the undesired N-->O-acyl migration that was observed under prolonged acid treatment used for cleaving the HmS peptide from the Wang resin.


Assuntos
Química/métodos , Serina/química , Alcenos/química , Anidridos/química , Espectroscopia de Ressonância Magnética , Modelos Químicos , Fragmentos de Peptídeos/química , Peptídeos/química , Ligação Proteica , Estrutura Terciária de Proteína , Soluções , Temperatura
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