15 research outputs found

    Anterior implant restorations with a convex emergence profile increase the frequency of recession: 12-month results of a randomized controlled clinical trial

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    AIM To test whether the emergence profile (CONVEX or CONCAVE) of implant-supported crowns influences the mucosal margin stability up to 12 months after insertion of the final restoration. MATERIALS AND METHODS Forty-seven patients with a single implant in the anterior region were randomly allocated to one of three groups: (1) CONVEX (n = 15), implant provisional and an implant-supported crown both with a convex profile; (2) CONCAVE (n = 16), implant provisional and an implant-supported crown both with a concave profile; (3) CONTROL (n = 16), no provisional (healing abutment only) and an implant-supported crown. All patients were recalled at baseline, 6, and 12 months. The stability of mucosal margin along with clinical, aesthetic, and profilometric outcomes as well as time and costs were evaluated. To predict the presence of recession, multivariable logistic regressions were performed and linear models using generalized estimation equations were conducted for the different outcomes. RESULTS Forty-four patients were available at 12 months post-loading. The frequency of mucosal recession amounted to 64.3% in group CONVEX, 14.3% in group CONCAVE, and 31.4% in group CONTROL. Regression models revealed that a CONVEX profile was significantly associated with the presence of recessions (odds ratio: 12.6, 95% confidence interval: 1.82-88.48, p = .01) compared with the CONCAVE profile. Pink aesthetic scores amounted to 5.9 in group CONVEX, 6.2 in group CONCAVE, and 5.4 in group CONTROL, with no significant differences between the groups (p = .735). Groups CONVEX and CONCAVE increased the appointments and costs compared with the CONTROL group. CONCLUSIONS The use of implant-supported provisionals with a CONCAVE emergence profile results in a greater stability of the mucosal margin compared with a CONVEX profile up to 12 months of loading. This is accompanied, however, by increased time and costs compared with the absence of a provisional and may not necessarily enhance the aesthetic outcomes. TRIAL REGISTRATION German Clinical Trials Register; DRKS00009420

    Constitutive and ghrelin-dependent GHSR1a activation impairs CaV2.1 and CaV2.2 currents in hypothalamic neurons

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    The growth hormone secretagogue receptor type 1a (GHSR1a) has the highest constitutive activity of any G protein coupled receptor (GPCR). GHSR1a mediates the action of the hormone ghrelin and, its activation increases transcriptional and electrical activity in hypothalamic neurons. It is known that GHSR1a is present at some specific GABAergic presynaptic terminals; however, its impact on neurotransmitter release remains elusive. The voltage gated calcium channels, CaV2.1 and CaV2.2, control neurotransmitter release at presynaptic terminals and their activities are modulated by many GPCRs. Here we show that constitutive as well as agonist-dependent GHSR1a activation trigger a strong impairment of both CaV2.1 and CaV2.2 currents in rat and mouse neurons and in a heterologous expression system. Constitutive GHSR1a activity reduces CaV2 currents by a Gi/o-dependent mechanism that involves persistent reduction in channel density at plasma membrane, whereas, ghrelin-dependent GHSR1a inhibition is reversible and involves altered CaV2 current gating via a Gq-dependent pathway. Thus, we show that GHSR1a differentially inhibits CaV2 channels by Gi/o- or Gq-protein pathways depending on its activation mode. Moreover, we present evidence suggesting that GHSR1a-mediated inhibition of CaV2 impairs GABA release in hypothalamic neurons, a mechanism that could contribute to neuronal activation by the disinhibition of postsynaptic neurons

    Veneered zirconia abutments cemented on non‐original titanium bases: 1‐year results of a prospective case series

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    Objectives To assess clinical, technical, and esthetic outcomes of veneered zirconia reconstructions cemented on non‐original titanium bases over 1 year. Materials and methods Twenty‐four healthy patients presented with one missing tooth in the anterior maxilla or mandible and received a two‐piece dental implant. The implants were restored with a screw‐retained crown using a directly veneered zirconia reconstruction, which was extraorally cemented on a titanium base. After crown insertion, patients were scheduled for a baseline examination and re‐examined at 6 months and at 1 year of loading. Measurements included biological, technical, and esthetic parameters. Data were analyzed with nonparametric tests. Results Mean marginal bone levels measured 0.54 ± 0.39 mm (median: 0.47, range: 0.07–1.75 mm) at baseline and 0.54 ± 0.45 mm (median: 0.44, range: 0.06–1.52 mm) at 1 year. Mean probing depth (PD) (3.0 ± 0.6 mm at baseline to 3.5 ± 0.7 mm at 1 year [p = 0.002]), bleeding on probing (BOP) (27.1% ± 20.7% at baseline to 43.9% ± 28.0% at 1 year [p = 0.041]), plaque index (PI) (11.1% ± 21.2% at baseline to 18.2% ± 21.8% at 1 year [p = 0.381]) increased, whereas the width of the keratinized mucosa decreased from baseline to 1 year (3.1 ± 1.3 mm at baseline to 3.0 ± 1.2 mm at 1 year [p = 0.398]). Four implants (16.7%) were diagnosed with peri‐implantitis (BOP positive, bone loss >1 mm) during the 1‐year observation period. One implant was lost at 3 Âœ months, resulting in a 95.8% survival rate. Four technical complications occurred and led to 83.3% complication‐free reconstructions. Conclusion A significant increase in PD and BOP values was observed using directly veneered zirconia reconstructions cemented on non‐original titanium base

    Veneered zirconia abutments cemented on non-original titanium bases: 1-year results of a prospective case series

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    To assess clinical, technical, and esthetic outcomes of veneered zirconia reconstructions cemented on non-original titanium bases over 1 year

    Randomized controlled clinical trial comparing one-piece and two-piece dental implants supporting fixed and removable dental prostheses: 4- to 6-year observations

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    OBJECTIVES To test whether or not a one- (S1) and a two-piece (S2) dental implant systems render the same biological, technical, and esthetic outcomes regarding implants and implant-supported reconstructions over an observation period of 4 to 6 years. MATERIALS AND METHODS Sixty patients were randomly assigned to receive S1 or S2 implants. The implants were restored with either fixed or removable prostheses. The insertion of the final reconstruction was chosen as baseline. One-year and 4- to 6-year (FU-5) measurements included biological (e.g. marginal bone level, probing pocket depth, peri-implant mucositis, and peri-implantitis), technical (e.g. fracture or loosening of prosthetic screws, fracture or loosening of abutments, fracture of framework, and/or veneering ceramic (minor, major), loss of retention for cemented restorations), and esthetic parameters (visibility of the crown margin, shimmering of the implant through the mucosa, the level of the facial margo mucosae compared to the contralateral tooth or implant site and the modified papilla index) for implants and reconstructions. Survival and success rates of implants and reconstructions were calculated. Because of the asymmetric data distributions, nonparametric statistical methods were applied. RESULTS The implant-based analysis revealed a cumulative implant survival rate of 97.9% (S1: 96.6%; S2: 98.9%) at FU-5. The median marginal bone level for group S1 changed from 0.51 mm at baseline to 0.49 mm at FU-5 and for group S2 from 1.02 mm to 1.35 mm (P 0.05). CONCLUSIONS Both implant systems reveal high survival rates on the implant and prosthetic level. Apart from marginal bone-level changes, biological and technical outcomes did not reveal significant differences between the two implant systems

    The Computer-based Health Evaluation Software (CHES): a software for electronic patient-reported outcome monitoring

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    Abstract Background Patient-reported Outcomes (PROs) capturing e.g., quality of life, fatigue, depression, medication side-effects or disease symptoms, have become important outcome parameters in medical research and daily clinical practice. Electronic PRO data capture (ePRO) with software packages to administer questionnaires, storing data, and presenting results has facilitated PRO assessment in hospital settings. Compared to conventional paper-pencil versions of PRO instruments, ePRO is more economical with regard to staff resources and time, and allows immediate presentation of results to the medical staff. The objective of our project was to develop software (CHES – Computer-based Health Evaluation System) for ePRO in hospital settings and at home with a special focus on the presentation of individual patient’s results. Methods Following the Extreme Programming development approach architecture was not fixed up-front, but was done in close, continuous collaboration with software end users (medical staff, researchers and patients) to meet their specific demands. Developed features include sophisticated, longitudinal charts linking patients’ PRO data to clinical characteristics and to PRO scores from reference populations, a web-interface for questionnaire administration, and a tool for convenient creating and editing of questionnaires. Results By 2012 CHES has been implemented at various institutions in Austria, Germany, Switzerland, and the UK and about 5000 patients participated in ePRO (with around 15000 assessments in total). Data entry is done by the patients themselves via tablet PCs with a study nurse or an intern approaching patients and supervising questionnaire completion. Discussion During the last decade several software packages for ePRO have emerged for different purposes. Whereas commercial products are available primarily for ePRO in clinical trials, academic projects have focused on data collection and presentation in daily clinical practice and on extending cancer registries with PRO data. CHES includes several features facilitating the use of PRO data for individualized medical decision making. With its web-interface it allows ePRO also when patients are home. Thus, it provides complete monitoring of patients‘physical and psychosocial symptom burden.</p

    Digital technologies to support planning, treatment, and fabrication processes and outcome assessments in implant dentistry. Summary and consensus statements. The 4th EAO consensus conference 2015

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    OBJECTIVE The aim of this multicenter randomized controlled clinical trial was to test posterior zirconia-ceramic fixed dental prostheses (FDPs) veneered with a computer-aided design/computer- assisted manufacture (CAD/CAM) lithium disilicate veneering ceramic (CAD-on) and manually layered zirconia veneering ceram OBJECTIVE The task of this working group was to assess the existing knowledge in computer-assisted implant planning and placement, fabrication of reconstructions applying computers compared to traditional fabrication, and assessments of treatment outcomes using novel imaging techniques. MATERIAL AND METHODS Three reviews were available for assessing the current literature and provided the basis for the discussions and the consensus report. One review dealt with the use of computers to plan implant therapy and to place implants in partially and fully edentulous patients. A second one focused on novel techniques and methods to assess treatment outcomes and the third compared CAD/CAM-fabricated reconstructions to conventionally fabricated ones. RESULTS The consensus statements, the clinical recommendations, and the implications for research, all of them after approval by the plenum of the consensus conference, are described in this article. The three articles by Vercruyssen et al., Patzelt & Kohal, and Benic et al. are presented separately as part of the supplement of this consensus conference.ic with respect to survival of the FDPs, and technical and biologic outcomes. METHOD AND MATERIALS Sixty patients in need of one posterior three-unit FDP were included. The zirconia frameworks were produced with a CAD/CAM system (Cerec inLab 3D/Cerec inEOS inLab). Thirty FDPs were veneered with a CAD/CAM lithium disilicate veneering ceramic (Cad-on) (test) and 30 were veneered with a layered zirconia veneering ceramic (control). For the clinical evaluation at baseline, 6, and 12 months, the United States Public Health Service (USPHS) criteria were used. The biologic outcome was judged by comparing the plaque control record (PCR), bleeding on probing (BOP), and probing pocket depth (PPD). Data were statistically analyzed. RESULTS Fifty-six patients were examined at a mean follow-up of 13.9 months. At the 1-year follow-up the survival rate was 100% in the test and in the control group. No significant differences of the technical outcomes occurred. Major chipping occurred in the control group (n = 3) and predominantly minor chipping in the test group (minor n = 2, major n = 1). No biologic problems or differences were found. CONCLUSIONS Both types of zirconia-ceramic FDPs exhibited very good clinical outcomes without differences between groups. Chipping occurred in both types of FDPs at small amounts, yet the extension of the chippings differed. The test FDPs predominantly exhibited minor chipping, the control FDPs major chipping

    Digital technologies to support planning, treatment, and fabrication processes and outcome assessments in implant dentistry. Summary and consensus statements. The 4th EAO consensus conference 2015

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    The task of this working group was to assess the existing knowledge in computer-assisted implant planning and placement, fabrication of reconstructions applying computers compared to traditional fabrication, and assessments of treatment outcomes using novel imaging techniques.status: publishe
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