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1.
Cell ; 158(1): 41-53, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24995977

RESUMO

A hallmark of type 2 diabetes mellitus (T2DM) is the development of pancreatic ß cell failure, which results in insulinopenia and hyperglycemia. We show that the adipokine adipsin has a beneficial role in maintaining ß cell function. Animals genetically lacking adipsin have glucose intolerance due to insulinopenia; isolated islets from these mice have reduced glucose-stimulated insulin secretion. Replenishment of adipsin to diabetic mice treated hyperglycemia by boosting insulin secretion. We identify C3a, a peptide generated by adipsin, as a potent insulin secretagogue and show that the C3a receptor is required for these beneficial effects of adipsin. C3a acts on islets by augmenting ATP levels, respiration, and cytosolic free Ca(2+). Finally, we demonstrate that T2DM patients with ß cell failure are deficient in adipsin. These findings indicate that the adipsin/C3a pathway connects adipocyte function to ß cell physiology, and manipulation of this molecular switch may serve as a therapy in T2DM.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Insulina/metabolismo , Tecido Adiposo/metabolismo , Animais , Complemento C3a/metabolismo , Fator D do Complemento/genética , Fator D do Complemento/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Dieta Hiperlipídica , Glucose/metabolismo , Humanos , Inflamação/metabolismo , Insulina/metabolismo , Secreção de Insulina , Camundongos
2.
J Prosthet Dent ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38772782

RESUMO

STATEMENT OF PROBLEM: The optimal pretreatment of radicular dentin before cementing a post with glass ionomer cement is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the retention of prefabricated tapered titanium posts to endodontically treated teeth after applying different pretreatment protocols on the radicular dentin. MATERIAL AND METHODS: The coronal part of 32 single-rooted human teeth was removed 1-mm coronally to the cemento-enamel junction. All specimens received endodontic treatment, and the root canals were prepared with an instrument to a depth of 10 mm to receive a titanium post. The dentin walls of each specimen were roughened with a hand-held diamond cutting instrument. The specimens were randomly divided according to the surface treatments into 4 groups (n=8): KW: etched with 20% to 30% polyacrylic acid (PAA) (Ketac Conditioner) and rinsed with water; KWI: etched with 20% to 30% PAA, rinsed with water and 70% isopropanol; DW: etched with 30% to 50% PAA (Durelon Liquid) and rinsed with water; DWI: etched with 30% to 50% PAA, rinsed with water and 70% isopropanol. The prefabricated titanium posts were airborne-particle abraded and cemented with glass ionomer cement. The specimens were fixed in custom-made brass cylindrical holders with autopolymerizing acrylic resin with the holder parallel to the long axis of the post. All specimens were stored in water for 3 days at 37 °C. Retention was evaluated using a tensile test with a universal testing machine (Zwick Z010) at a crosshead speed of 2 mm/min. Data were statistically analyzed with a 1-way ANOVA, followed by the Tukey post hoc test for pairwise comparisons between groups (α=.05). RESULTS: Mean ±standard deviation retention values ranged from 201.8 ±55.5 N (KW) to 328.1 ±70.9 N (DWI). Groups DWI and KWI (316 ±58.3 N) showed statistically higher retention values than group KW (P<.05) but did not significantly differ from retention values obtained in group DW (P>.05). CONCLUSIONS: An additional final rinse with isopropanol after using PAA increased the retention of the post significantly for all groups. Although group DWI achieved the highest retention values, pretreatment of radicular dentin as in group KWI may also be considered.

3.
J Prosthet Dent ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38402134

RESUMO

STATEMENT OF PROBLEM: The influence of the ferrule thickness and post materials on the fracture resistance of endodontically treated teeth remains unclear. PURPOSE: The purpose of this laboratory study was to evaluate the influence of post material and ferrule thickness on the fracture resistance of endodontically treated mandibular premolars. MATERIAL AND METHODS: Sixty-four extracted and endodontically treated mandibular first premolars were used and divided into 4 test groups (n=16) depending on the ferrule thickness: F-0: without a ferrule, F-0.5: with a 0.5-mm ferrule thickness, F-1: with a 1-mm ferrule thickness, and F-1.5: with a 1.5-mm ferrule thickness. In groups with ferrules, the height ranged from 2 mm buccally/lingually to 1 mm proximally. Teeth in subgroups (n=8) were restored with either prefabricated glass fiber (FF) or titanium posts (FT) (ISO size 70 and length of 7.5 mm) and then adhesively restored with composite resin foundation materials. After foundation procedures, each specimen was restored with a cobalt chromium crown which was cemented with glass-ionomer cement. All specimens were subjected to dynamic loading in a masticatory simulator for 1 200 000 loading cycles with a nominal load of 5 Kg at 1.2 Hz and simultaneous thermocycling (5 to 55 °C). Specimens were then quasistatically loaded at 30 degrees in a universal testing machine until fracture. Fracture loads were analyzed by using 2-way ANOVA followed by the Tukey honestly significant difference test (α=.05). RESULTS: Fracture loads ranged from 610 ±45 N (no ferrule - glass fiber post) to 1216 ±169 N (1.5 mm ferrule thickness - glass fiber post). A statistically significant increase in fracture resistance was observed with increasing ferrule thickness (P<.001). However, post materials did not show a statistically significant influence (P=.977). CONCLUSIONS: Under the conditions of this laboratory study, increasing the ferrule thickness had a significant effect on the fracture resistance of endodontically treated teeth after thermomechanical fatigue, irrespective of post materials.

4.
BMC Oral Health ; 24(1): 291, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38429695

RESUMO

BACKGROUND: Achieving sufficient professional mechanical biofilm removal (PMPR) can be challenging in supportive periodontal therapy (SPT), particularly in patients with prosthetic restorations. This experimental study aimed to simulate five years of SPT with periodic PMPR near the luting gap of ceramic restorations using a rubber cup with polishing paste (RCP), air polishing with two different low-abrasive powders (LAPA-1: glycine powder, LAPA-2: erythritol powder), and non-professional mechanical cleaning (control group) to measure the extent of volume loss in the luting gap after baseline (∆V = Vbaseline-V1-5; in µm3). METHODS: Two operators randomly performed PMPR ten times for thirty seconds on one of four sides of 30 crown replicas fixed with glass-ionomer cement (CGIZ: n = 15) or adhesive bonding (CAB: n = 15). The replicas were separated in a template during PMPR, and afterward, cleaned for five seconds per side with a sonic brush under flowing water. The artificial aging process between two PMPRs simulated a 5-year SPT with two PMPRs per year. Profilometric measurements were performed at baseline and after each second PMPR to obtain the mean change of ∆V. The statistical evaluation of the data was carried out using nonparametric tests with Bonferroni correction applied for multiple tests. RESULTS: Ninety-six out of 120 sides could be included in the analysis. PMPR methods showed a loss of substance in the luting gap with a ∆V (mean(standard deviation)) of -4.35 × 106(4.8 × 106)µm3 versus 8.79 × 104(1.05 × 106)µm3 for control at V5 (p ≤ 0.001). No significant differences of ∆V1-5 values could be identified in the control (p > 0.05), whereat all PMPRs showed a significant increasing loss of substance per simulated year (p ≤ 0.001). Intergroup comparison identified LAPA-1 as having the highest significant loss of substance determined on CAB (∆V: -1.05 × 107 (7,2 × 106) µm3), followed by LAPA-2 on CAB (∆V: -6.29 × 106 (4,24 × 106) µm3), LAPA-1 on CGIZ (∆V: -4.15 × 106 (3,25 × 106) µm3), LAPA-2 on CGIZ (∆V: -3.0 × 106 (2,23 × 106) µm3), RCP on CAB (∆V: -1.86 × 106 (2,23 × 106) µm3) and CGIZ (∆V: -1.2 × 106 (1,31 × 106) µm3; p ≤ 0.001)). CONCLUSIONS: Within study limitations, all PMPRs caused a significantly higher loss of substance in the luting gap versus control without professional intervention, with the highest values in the CAB group for LAPA-1, LAPA-2 and RCP. Similar findings were observed for CGIZ, although the loss values were lower.


Assuntos
Cerâmica , Resinas Compostas , Humanos , Pós , Propriedades de Superfície , Cimentos de Ionômeros de Vidro
5.
Proc Natl Acad Sci U S A ; 117(13): 7471-7481, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32170013

RESUMO

Eps15-homology domain containing protein 2 (EHD2) is a dynamin-related ATPase located at the neck of caveolae, but its physiological function has remained unclear. Here, we found that global genetic ablation of EHD2 in mice leads to increased lipid droplet size in fat tissue. This organismic phenotype was paralleled at the cellular level by increased fatty acid uptake via a caveolae- and CD36-dependent pathway that also involves dynamin. Concomitantly, elevated numbers of detached caveolae were found in brown and white adipose tissue lacking EHD2, and increased caveolar mobility in mouse embryonic fibroblasts. EHD2 expression itself was down-regulated in the visceral fat of two obese mouse models and obese patients. Our data suggest that EHD2 controls a cell-autonomous, caveolae-dependent fatty acid uptake pathway and imply that low EHD2 expression levels are linked to obesity.


Assuntos
Proteínas de Transporte/metabolismo , Cavéolas/metabolismo , Ácidos Graxos/metabolismo , Animais , Transporte Biológico , Membrana Celular/metabolismo , Células HeLa , Humanos , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
6.
J Esthet Restor Dent ; 35(1): 64-73, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36579757

RESUMO

OBJECTIVES: To present an update on the concept of cantilevered single-retainer all-ceramic resin-bonded fixed dental prostheses (RBFDPs) first presented 25 years ago in the Journal of Esthetic Dentistry. OVERVIEW: The initially presented case of the concept was followed clinically over 26 years and is presented along with two additional clinical long-term cases using varying methods to obtain an esthetic and hygienic ovate pontic design. Veneered alumina and zirconia ceramic (3 mol% yttria-tetragonal zirconia polycrystalline ceramic; 3Y-TZP) was used and bonded with a phosphate monomer containing luting resin after 50 µm alumina particle air-abrasion at 0.25 MPa pressure. The restorations replacing incisors did not debond and soft tissues in the pontic area were maintained over 26 years. CONCLUSIONS: Cantilevered single-retainer all-ceramic RBFDPs today made from veneered 3Y-TZP zirconia ceramic can be considered a standard of care for the replacement of single incisors and provide an excellent esthetic outcome with a long-term preservation of soft tissues in the pontic area. CLINICAL SIGNIFICANCE: Bonding nonretentive oxides ceramics such as alumina and zirconia ceramic with phosphate monomer containing luting resins after alumina particle air-abrasion is durable over decades. This proves that bonding to zirconia ceramic is not of any problem when adequate methods are used. Single-retainer zirconia ceramic RBFDPs maintain soft tissues in the edentulous area of single missing incisors and often deem implants unessential for this indication.


Assuntos
Colagem Dentária , Cimentos de Resina , Óxido de Alumínio/química , Cerâmica/química , Prótese Parcial Fixa , Estética Dentária , Fosfatos/química , Cimentos de Resina/química , Zircônio/química
7.
J Prosthet Dent ; 130(1): 119-123, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34736765

RESUMO

STATEMENT OF PROBLEM: Scientific data to support scannable and computer-aided design and computer-aided manufacturing (CAD-CAM)-compatible interocclusal registration materials are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the ability of different registration materials (conventional versus scannable) to record maxillary-mandibular relationships and compare the dimensional stability of these records after storage times of 1 hour and 48 hours. MATERIAL AND METHODS: Six groups of interocclusal registration materials were tested: 3 conventional (Registrado X-tra, Futar D Fast, and O-Bite) and 3 scannable (Registrado Scan, Futar Cut & Trim Fast, and O-Bite Scan). Eight registrations were made for each group by using a custom-made device with a dial gauge to measure vertical discrepancies. Records were stored at room temperature, and discrepancies measured after 1 hour and 48 hours. The data were statistically analyzed with the Wilcoxon test with respect to time and the Kruskal-Wallis test with respect to materials, followed by the Mann-Whitney test with the Bonferroni-Holm correction (α=.05). RESULTS: The median vertical discrepancies ranged from -2 µm (FS) to 11 µm (O-Bite) after 1 hour and from 3 µm (Futar Cut & Trim Fast) to 13 µm (Registrado X-tra and O-Bite) after 48 hours. A statistically significant difference (P<.001) was found between the results after 1 hour and 48 hours for all materials. All scannable interocclusal registration materials showed significantly lower vertical discrepancies than the corresponding conventional materials after 1 hour and 48 hours (P<.05). CONCLUSIONS: All registration materials showed vertical discrepancies that might be clinically acceptable. Vertical discrepancies increased after 48 hours of storage for all materials but were still clinically acceptable.


Assuntos
Materiais para Moldagem Odontológica , Siloxanas , Registro da Relação Maxilomandibular , Polivinil , Oclusão Dentária , Desenho Assistido por Computador
8.
J Prosthet Dent ; 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37438166

RESUMO

STATEMENT OF PROBLEM: Scientific data on the decontamination effectiveness of a newly introduced cleaning agent are lacking. PURPOSE: The purpose of this in vitro study was to evaluate and compare the tensile bond strength (TBS) of 3 different restorative bonding surfaces after contamination with saliva following different cleaning protocols. MATERIAL AND METHODS: A total of 192 disk specimens were made out of 3 materials (n=64); Katana Avencia (A), Katana Zirconia (Z), and e.max CAD (L). The bonding surfaces of all disks were polished, steam cleaned, and then pretreated by following the recommended protocol for each material. The specimens of each group were divided into 4 subgroups (n=16). The first subgroup served as the reference (R), where no contamination was applied. The 3 other subgroups were contaminated with saliva and subsequently rinsed with water for 20 seconds and dried with oil- and water-free air spray. They were then either not treated with any cleaning method (0), cleaned with Katana Cleaner (K), or cleaned with Ivoclean (I). The bonding surfaces of the specimens were perpendicularly luted to plexiglass tubes filled with dual-polymerizing composite resin (Clearfil DC Core) with resin cement (Panavia V5) after the recommended surface conditioning. Each subgroup was further subdivided into 2 groups: stored in 37 °C water for 3 days or subjected to thermal-cyclic loading for 150 days with 37 500 thermal cycles (7500 per month), temperature 5 to 55 °C, and dwell time of 30 seconds. All specimens were subjected to TBS testing in a universal testing machine. Three-way ANOVA was applied. A significant interaction (P<.01) was detected between the 3 different variables (material, treatment, aging). After significant interactions had been revealed by 3-way ANOVA, additional statistical analysis was performed by using separate 2-way ANOVAs, then separate 1-way ANOVAs followed by the Tukey-HSD test for post hoc pairwise comparisons among groups (α=.05 for all tests). All specimens underwent failure mode analysis after TBS testing RESULTS: All specimens survived the storage with thermocycling except for group Z-0, where all specimens debonded during thermocycling. The mean ±standard deviation TBS values ranged from 18.3 ±5.3 MPa to 34.0 ±5.4 MPa after 3 days and from 6.7 ±5.5 MPa to 26.9 ±5.4 MPa after 150 days. CONCLUSIONS: Contaminated groups that did not receive any cleaning had significantly lower TBS. Thermocycling had a negative effect on the TBS but was not statistically significant for all groups. Using the same cleaning method, the restorative material did had a significant effect on the TBS after 150 days.

9.
Int J Comput Dent ; 26(3): 257-264, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36695627

RESUMO

AIM: The aim of the present article is to describe a new method to reduce the undesirable loss of material thickness that results from overmilling due to the tool diameter compensation correction of common CAD/CAM software. MATERIALS AND METHODS: Today's CAD/CAM software (eg, 3Shape or Exocad) specifies the same tool diameter compensation for different ceramics. In the case of zirconia ceramics milled in the raw state, this leads to excessive milling of the inner surfaces of crowns, which results in unnecessarily large cementation gaps and a restoration that is thinned out from the inside. By manually reducing the preset correction in the digital design process by the volumetric sintering shrinkage factor specified by the manufacturer, excessive thinning of the zirconia can be avoided. RESULTS: The inner geometry of the restorations changes only slightly after manually reducing the preset tool diameter compensation correction. Consequently, a design of the restoration with the required minimum interocclusal thickness yet with accurate passive seating and marginal fit is possible without any further interventions. CONCLUSIONS: Understanding the specifics of the subtractive fabrication process as well as the properties of the restorative materials is a key factor in achieving optimal clinical outcomes with all-ceramic restorations fabricated with CAD/CAM technology. The use of monolithic zirconia combined with a calculated reduction in the preset tool diameter compensation correction might be beneficial in cases with thin or uneven geometry.


Assuntos
Adaptação Marginal Dentária , Planejamento de Prótese Dentária , Humanos , Planejamento de Prótese Dentária/métodos , Materiais Dentários , Cerâmica , Coroas , Zircônio , Desenho Assistido por Computador , Porcelana Dentária , Teste de Materiais
10.
Int J Comput Dent ; 0(0): 0, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37417447

RESUMO

AIM: To investigate the effect of using different materials for the fabrication of implant abutments and crowns on the mechanical behavior of implant-supported single crowns after artificial aging. The materials were tested in different combinations to reveal whether using stiff or resilient materials as an abutment or a crown material might influence the fracture strength of the whole structure. MATERIALS AND METHODS: A total of 40 implants (blueSKY, bredent GmbH & Co. KG) were restored with identical custom-made CAD/CAM abutments milled out of lithium disilicate or ceramic-reinforced PEEK and were divided into 5 test groups (n = 8 each). Forty crowns made of three different materials (zirconia, lithium disilicate, and ceramic-reinforced PEEK) were used to restore the abutments. Specimens were subjected to mechanical load up to 1,200,000 cycles in a chewing simulator (Kausimulator, Willytech) with additional thermal cycling. The surviving specimens were subjected to quasi-static loading using a universal testing machine (Z010, Zwick). RESULTS: PEEK abutments with zirconia crowns showed the highest median failure load (3890.5 N), while PEEK abutments with lithium disilicate crowns exhibited the lowest (1920 N). Fracture and deformation occurred in both crowns and abutments. CONCLUSION: The failure load of the restorations was influenced by the material of the abutment and the crown. Restoring PEEK abutments with zirconia crowns showed a high failure load and no screw loosening.

11.
J Prosthodont ; 32(3): e52-e63, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35771977

RESUMO

PURPOSE: Various surface roughness parameters are utilized to describe the surface in the tooth to ceramics abrasion and to assess the resulting wear. The use of three-dimensional parameters may offer a better estimation for wear and an improved deduced clinical surface treatment. The aim of this study was to determine the influence of various surface roughness parameters of zirconia and lithium disilicate ceramics on the wear of steatite antagonists. MATERIAL AND METHODS: Forty zirconia specimens with a diameter of 7 mm and a thickness of 3 mm and 40 lithium disilicate specimens with the dimensions 10×10×4 mm were each divided into five subgroups. Two subgroups were treated with different clinically established diamond burs; a third subgroup was treated with a silicone polishing set. Two additional subgroups were produced by glazing the surfaces after treatment. Surface roughness parameters were determined by laser scanning microscopy. All specimens underwent 1.2 million loading cycles using steatite antagonists. After regular intervals of cycles, precision impressions were made to assess the wear. The correlation between wear and different roughness parameters was evaluated using the Spearman correlation test. RESULTS: For the glazed zirconia, unglazed zirconia, and glazed lithium disilicate specimens no significant correlations (p > 0.05) between the investigated roughness parameters and antagonist wear could be found. In the unglazed lithium disilicate groups, significant (p ≤ 0.05) correlations with steatite substance loss could be found for several roughness parameters after 1.2 million cycles. CONCLUSIONS: For lithium disilicate, it seems not sufficient to use only one roughness parameter to indicate the wear behavior of the surface. There was no correlation between wear and the tested roughness parameters of zirconia surfaces.


Assuntos
Cerâmica , Porcelana Dentária , Propriedades de Superfície , Teste de Materiais , Zircônio
12.
J Evid Based Dent Pract ; 23(1S): 101794, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36707170

RESUMO

BACKGROUND: When dental patients seek care, treatments are not always successful,that is patients' oral health problems are not always eliminated or substantially reduced. Identifying these patients (treatment non-responders) is essential for clinical decision-making. Group-based trajectory modeling (GBTM) is rarely used in dentistry, but a promising statistical technique to identify non-responders in particular and clinical distinct patient groups in general in longitudinal data sets. AIM: Using group-based trajectory modeling, this study aimed to demonstrate how to identify oral health-related quality of life (OHRQoL) treatment response patterns by the example of patients with a shortened dental arch (SDA). METHODS: This paper is a secondary data analysis of a randomized controlled clinical trial. In this trial SDA patients received partial removable dental prostheses replacing missing teeth up to the first molars (N = 79) either or the dental arch ended with the second premolar that was present or replaced by a cantilever fixed dental prosthesis (N = 71). Up to ten follow-up examinations (1-2, 6, 12, 24, 36, 48, 60, 96, 120, and 180 months post-treatment) continued for 15 years. The outcome OHRQoL was assessed with the 49-item Oral Health Impact Profile (OHIP). Exploratory GBTM was performed to identify treatment response patterns. RESULTS: Two response patterns could be identified - "responders" and "non-responders." Responders' OHRQoL improved substantially and stayed primarily stable over the 15 years. Non-responders' OHRQoL did not improve considerably over time or worsened. While the SDA treatments were not related to the 2 response patterns, higher levels of functional, pain-related, psychological impairment in particular, and severely impaired OHRQoL in general predicted a non-responding OHRQoL pattern after treatment. Supplementary, a 3 pattern approach has been evaluated. CONCLUSIONS: Clustering patients according to certain longitudinal characteristics after treatment is generally important, but specifically identifying treatment in non-responders is central. With the increasing availability of OHRQoL data in clinical research and regular patient care, GBTM has become a powerful tool to investigate which dental treatment works for which patients.


Assuntos
Prótese Parcial Removível , Qualidade de Vida , Humanos , Prótese Parcial Removível/psicologia , Arco Dental , Saúde Bucal , Dente Molar
13.
Clin Oral Implants Res ; 33(10): 1030-1037, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35869607

RESUMO

OBJECTIVES: To investigate the chewing efficiency and oral health-related quality of life of edentulous patients wearing complete dentures, successively supported by one, two, and three implants in the mandible. METHODS: Thirteen (13) edentulous patients of at least 50 years of age received three implants in the mandible. After a conventional submerged healing period, the central implant was uncovered and connected to the denture base using a stud attachment. Two months later, chewing efficacy was evaluated, and the two lateral implants were uncovered and connected to the denture base. The central retention element was replaced by a short healing abutment with no connection to the denture base. Chewing efficiency was evaluated two months later. Afterward, the healing abutment of the central implant was replaced by a stud attachment and again connected to the denture base. Two months later, chewing efficacy was evaluated again. Oral health-related quality of life (OHRQoL) was measured at each recall visit using the summary score of the oral health impact profile. For statistical analysis of chewing efficacy, the changes from baseline (with no implants) to one, two, and three implants were used and tested by analysis of variance with repeated mesurements. RESULTS: Chewing efficacy clearly increased after implant loading, with a significant increase when two implants were loaded (p ≤ .05), compared to the chewing efficacy with no implants. OHRQoL also significantly improved after implant loading. CONCLUSIONS: Within the limitations of the present clinical trial regarding the number of patients, chewing efficacy as well OHRQoL of edentulous patients improve after implant placement in the mandible, irrespective of the number of implants. The best chewing efficacy was achieved with two implants.


Assuntos
Implantes Dentários , Arcada Edêntula , Boca Edêntula , Prótese Dentária Fixada por Implante , Retenção de Dentadura , Revestimento de Dentadura , Humanos , Arcada Edêntula/cirurgia , Mandíbula/cirurgia , Mastigação , Boca Edêntula/cirurgia , Satisfação do Paciente , Qualidade de Vida
14.
Clin Oral Investig ; 26(12): 6973-6983, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35906341

RESUMO

OBJECTIVES: The aim of this study is to analyze the esthetic perception of selected canine features, namely crown length, shade, inclination, and angle of incisal edge tip. MATERIALS AND METHODS: The anterior maxillary teeth of a Central European woman were photographed and digitally modified in order to investigate esthetic perceptions of the above four categories. Three groups of examiners with different levels of experience in the field of dentistry (laypersons/inexperienced dental students, advanced dental students, dentists) evaluated the photographs twice with the help of visual analogue scales. RESULTS: The best-evaluated canines have approximately the same length as the central incisor, have the same shade as the other anterior teeth, are best embedded in a lighter overall tooth shade, are neutral to slightly palatal inclined, and have a right angled to rounded incisal edge (≥ 90°). The canines evaluated as least esthetic, however, are longer than the central incisors, darker, inclined labially, and have a tapered incisal edge. No significant differences could be found between the evaluations of the groups with regard to the four feature categories. CONCLUSIONS: Laypersons, advanced dental students, and dentists generally evaluate according to the same esthetic standards. Gender does not have a significant influence on evaluation. Clear definitions of esthetically favored shades, incisal edge shapes, inclination, and lengths of the canines can be given. CLINICAL RELEVANCE: Since the esthetics of the smile line play a critical role for patients, dentists, dental technicians, and their supplying industry, knowledge of the esthetically preferred morphology of canines is essential. CLINICAL SIGNIFICANCE: The aim of this study is to give clear definitions of esthetically favored shades, incisal edge shapes, and lengths of the canines, as the esthetics of the smile line play a critical role for patients, dentists, dental technicians, and their supplying industry (e.g., denture tooth manufacturers). Precise knowledge of esthetic preferences is important in clinical practice for both dentists and dental technicians, for example, in order to adequately advise patients regarding esthetic corrections. Also, in the case of missing teeth, this knowledge is essential for optimal and satisfactory restorations. Thus, this study can contribute to the satisfaction of general practitioners and patients.


Assuntos
Estética Dentária , Incisivo , Humanos , Incisivo/anatomia & histologia , Odontólogos , Maxila/anatomia & histologia , Percepção
15.
Clin Oral Investig ; 26(3): 3311-3323, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34985576

RESUMO

OBJECTIVES: The aim of this study is to investigate vascular and neurosensory complications in edentulous patients following the installation of mandibular midline single implants in relation to lingual canals. MATERIALS AND METHODS: After performing a cone beam computed tomography scan for the 50 recruited patients, the relationship between the potential implant site and the lingual canals was assessed, and all vascular and neurosensory complications were recorded. RESULTS: Six patients (12%) reported profuse bleeding during implant placement, and 13 (26%) reported transient neurosensory changes, which were resolved after 3 months. According to the virtual implant planning, 44 patients (88%) would have their implants touching the lingual canals, six of them reported vascular changes (14%), and 12 out of 44 patients reported neurosensory changes (27%). For the six patients who would have their implants not touching the lingual canals, one patient reported transient neurosensory changes. CONCLUSIONS: The mandibular lingual canals are constant anatomic landmarks. Injury to the supra-spinosum lingual canals may occur during midline implant placement, depending on the implant length and the bone height. CLINICAL RELEVANCE: Despite that injury to the supra-spinosum lingual canals during implant insertion does not result in permanent vascular or neurosensory complications, caution is required to avoid the perforation of the lingual cortices.


Assuntos
Implantes Dentários , Mandíbula , Pontos de Referência Anatômicos , Tomografia Computadorizada de Feixe Cônico , Implantação Dentária Endóssea/métodos , Humanos , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia
16.
Int J Mol Sci ; 23(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35216336

RESUMO

(1) Adipsin is an adipokine that may link increased fat mass and adipose tissue dysfunction to obesity-related cardiometabolic diseases. Here, we investigated whether adipsin serum concentrations and adipose tissue (AT) adipsin mRNA expression are related to parameters of AT function, obesity and type 2 diabetes (T2D). (2) Methods: A cohort of 637 individuals with a wide range of age and body weight (Age: 18-85 years; BMI: 19-70 kg/m2) with (n = 237) or without (n = 400) T2D was analyzed for serum adipsin concentrations by ELISA and visceral (VAT) and subcutaneous (SAT) adipsin mRNA expression by RT-PCR. (3) Results: Adipsin serum concentrations were significantly higher in patients with T2D compared to normoglycemic individuals. We found significant positive univariate relationships of adipsin serum concentrations with age (r = 0.282, p < 0.001), body weight (r = 0.264, p < 0.001), fasting plasma glucose (r = 0.136, p = 0.006) and leptin serum concentrations (r = 0.362, p < 0.001). Neither VAT nor SAT adipsin mRNA expression correlated with adipsin serum concentrations after adjusting for age, sex and BMI. Independent of T2D status, we found significantly higher adipsin expression in SAT compared to VAT (4) Conclusions: Our data suggest that adipsin serum concentrations are strongly related to obesity and age. However, neither circulating adipsin nor adipsin AT expression reflects parameters of impaired glucose or lipid metabolism in patients with obesity with or without T2D.


Assuntos
Tecido Adiposo/metabolismo , Fator D do Complemento/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Obesidade/metabolismo , Idoso , Glicemia/metabolismo , Índice de Massa Corporal , Feminino , Humanos , Insulina/metabolismo , Gordura Intra-Abdominal/metabolismo , Masculino , Pessoa de Meia-Idade , Circunferência da Cintura/fisiologia
17.
Clin Oral Implants Res ; 32(2): 212-221, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33258136

RESUMO

OBJECTIVES: This multicenter randomized controlled clinical trial was conducted to investigate whether the loading protocol of single dental implants placed in the midline of edentulous mandibles will influence the implant survival or prosthetic maintenance. MATERIALS AND METHODS: In total, 158 patients were randomly assigned either to the immediate loading group (n = 81) or to the delayed loading group (n = 77). All implants were loaded with an overdenture retained by a ball attachment. RESULTS: After 5 years, 102 patients attended the follow-up investigation. Immediately loaded single implants in the midline of the edentulous mandible revealed a statistically significant lower survival rate than implants loaded conventionally over an observation period of 5 years. In the immediate loading group, 9 implants failed within the first three months of implant loading. No further implant loss was recorded for this group. Two implants failed in the delayed loading group, whereas one implant had to be removed during second-stage surgery and the second five years after implant loading. Non-inferiority of the survival rate of the midline implant of the immediate loading group, compared with the delayed loading group, could not be shown (p = .79, CI immediate loading: 74.9%; 100.0%, CI delayed loading: 73.0%; 100.0%). The observed difference in implant survival between the two treatment groups over time was statistically significant. CONCLUSIONS: The results of the present study indicate that immediate loading of a single mandibular implant in the edentulous mandible should be considered only in exceptional cases.


Assuntos
Implantes Dentários , Carga Imediata em Implante Dentário , Arcada Edêntula , Implantação Dentária Endóssea , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Revestimento de Dentadura , Humanos , Arcada Edêntula/cirurgia , Mandíbula/cirurgia , Resultado do Tratamento
18.
J Oral Rehabil ; 48(6): 738-744, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33713361

RESUMO

BACKGROUND: Few long-term studies on treatments in the shortened dental arch (SDA) are available. OBJECTIVE: The objective of this trial was to analyse the long-term success of two different treatment concepts. METHODS: Patients over 35 years of age with missing molars in one jaw and at least the canine and one premolar present on both sides were eligible. In the partial removable dental prosthesis (PRDP) group (N = 81), molars and missing second premolars were replaced by a precision attachment retained prosthesis. In the SDA group (N = 71), the dental arch ended with the second premolar that had to be present or replaced by a cantilever fixed dental prosthesis. Follow-up examinations were carried out over 15 years. RESULTS: A comprehensive outcome variable comprised four failure categories for which Kaplan-Meier survival (success) analyses were conducted. Half of the patients exhibited a continuous preservation of the per protocol prosthetic status that remained totally unaffected by complications for more than 10 years. The event-free success rates for moderate or worse failure implied a loss of the per protocol prosthetic status. The respective survival rates fell below 50% at 14.2 years in the PRDP group and 14.3 years in the SDA group. In none of the analyses, a significant group difference was found. CONCLUSIONS: In patients with an SDA condition, changes in the prosthetic status have to be expected. The affected proportion increases almost linearly from shortly after treatment and comprises the majority after 15 years. The influence of the examined treatments on success appears to be low.


Assuntos
Prótese Parcial Removível , Arcada Parcialmente Edêntula , Perda de Dente , Dente Pré-Molar , Arco Dental , Humanos
19.
J Esthet Restor Dent ; 33(3): 415-421, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32945608

RESUMO

OBJECTIVE: Single-retainer resin-bonded fixed dental prostheses (RBFDPs) are described as an excellent minimally invasive treatment modality for the replacement of a single missing incisor even in cases of congenitally missing teeth that are often associated with hard and soft tissue defects that need to be properly managed to optimize the esthetic outcome. The lack of a retentive form due to the minimally invasive preparation form makes the adhesive bonding procedure for RBFDPs relatively technique-sensitive and might discourage practitioners from offering this treatment modality. CLINICAL CONSIDERATIONS: A patient with both maxillary lateral incisors congenitally missing was assessed for eligibility for treatment with RBFDPs. Bilateral horizontal ridge defects were present and treated through ridge augmentation to ensure an ovate pontic design and enhance the esthetic outcome. A minimally invasive preparation within enamel was conducted; the restorations were digitally designed and milled out of (3Y-TZP) zirconia ceramic with labial veneering with feldspathic ceramic for enhanced esthetics. An improved design of positioning splints was used for the adhesive bonding procedure to ensure exact, secure, and flawless insertion of the restorations. CONCLUSIONS: RBFDPs offer a highly esthetic treatment modality for missing teeth in the anterior area. Tissue defects could be overcome be means of a minor oral surgery, while using improved positioning splints might ensure flawless adhesive bonding and promote the usage of RBFDPs. CLINICAL SIGNIFICANCE: Hard and soft tissue defects can be remarkably optimized through a minor ridge augmentation. Improved positioning splints allow an easy and secure positioning as well as visual inspection of the seating in end-position and complete removal of resin cement excess. Implementing the concept of insertion splints might promote RBFDPs for anterior tooth replacement as it helps preventing bonding errors.


Assuntos
Colagem Dentária , Prótese Adesiva , Cerâmica , Prótese Parcial Fixa , Humanos , Cimentos de Resina , Contenções
20.
Int J Mol Sci ; 22(9)2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33919448

RESUMO

Genome-wide association studies have identified adenylyl cyclase type 5 (ADCY5) as candidate gene for diabetes-related quantitative traits and an increased risk of type 2 diabetes. Mice with a whole-body deletion of Adcy5 (Adcy5-/-) do not develop obesity, glucose intolerance and insulin resistance, have improved cardiac function and increased longevity. Here, we investigated Adcy5 knockout mice (Adcy5-/-) to test the hypothesis that changes in adipose tissue (AT) may contribute to the reported healthier phenotype. In contrast to previous reports, we found that deletion of Adcy5 did not confer any physiological or biochemical benefits. However, this unexpected finding allowed us to investigate the effects of Adcy5 depletion on AT independently of lower body weight and a metabolically healthier phenotype. Adcy5-/- mice exhibited an increased number of smaller adipocytes, lower mean adipocyte size and a distinct AT gene expression pattern with midline 1 (Mid1) as the most significantly downregulated gene compared to control mice. Our Adcy5-/- model challenges previously described beneficial effects of Adcy5 deficiency and suggests that targeting Adcy5 does not improve insulin sensitivity and may therefore limit the relevance of ADCY5 as potential drug target.


Assuntos
Adenilil Ciclases/fisiologia , Tecido Adiposo/patologia , Intolerância à Glucose/patologia , Resistência à Insulina , Insulina/metabolismo , Obesidade/patologia , Tecido Adiposo/metabolismo , Animais , Intolerância à Glucose/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/metabolismo
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