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1.
J Phys Chem A ; 128(14): 2752-2762, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38551124

RESUMO

Aluminum monofluoride (AlF) is a suitable molecule for laser cooling and trapping. Such experiments require extensive spectroscopic characterization of the electronic structure. Two of the theoretically predicted higher-lying triplet states of AlF, the counterparts of the well-characterized D1Δ and E1Π states, had not been experimentally identified yet. We here report on the characterization of the d3Π (v = 0-6) and e3Δ (v = 0-2) states, confirming the predicted energetic ordering of these states (J. Chem. Phys. 1988, 88, 5715-5725), as well as of the f3Σ+ (v = 0-2) state. The transition intensity of the d3Π, v = 3 - a3Π, v = 3 band is negligibly small. This band gets its weak, unexpected rotational structure via intensity borrowing from the nearby e3Δ, v = 2 - a3Π, v = 3 band, made possible via spin-orbit and spin-rotation interaction between the d3Π and e3Δ states. This interaction affects the equilibrium rotational constants in both states; their deperturbed values yield equilibrium internuclear distances that are consistent with the observations. We determined the ionization potential of AlF to be 78,492(1) cm-1 by ionization from the d3Π state.

3.
Int J Oral Maxillofac Surg ; 52(4): 413-416, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36008220

RESUMO

Osseointegrated dental implants in the vicinity of oral squamous cell carcinoma (OSCC) will become more common given the increasing popularity of dental implants. Reports and studies of OSCC around dental implants are rare, as is the topic of how to handle OSCC surgically when implants are in contact with the tumour. In view of this uncertainty, a histological study was performed to assess tumour behaviour around implants. The aim was to determine whether an implant facilitates inward growth of the tumour and how this should be taken into account during staging and treatment planning. A total of 20 specimens were collected. The implants were macroscopically in contact with OSCC in 13 of the 20 specimens. Histologically, tumour tissue near the implant was indeed confirmed in nine of these cases. In seven cases, tumour invasion had led to resorption of the underlying jaw bone; tumour between the bone-implant interface was identified in only two of these cases, but without downward growth along the implant. In conclusion, no proof was found to confirm that the bone-implant interface is a preferred route for invasion. Therefore, dental implants in the vicinity of OSCC should not influence staging and treatment planning in this regard.


Assuntos
Perda do Osso Alveolar , Carcinoma de Células Escamosas , Implantes Dentários , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Implantação Dentária Endóssea
4.
ESMO Open ; 7(6): 100611, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36463731

RESUMO

BACKGROUND: In ∼3%-5% of patients with metastatic disease, tumor origin remains unknown despite modern imaging techniques and extensive pathology work-up. With long diagnostic delays and limited and ineffective therapy options, the clinical outcome of patients with cancer of unknown primary (CUP) remains poor. Large-scale genome sequencing studies have revealed that tumor types can be predicted based on distinct patterns of somatic variants and other genomic characteristics. Moreover, actionable genomic events are present in almost half of CUP patients. This study investigated the clinical value of whole genome sequencing (WGS) in terms of primary tumor identification and detection of actionable events, in the routine diagnostic work-up of CUP patients. PATIENTS AND METHODS: A WGS-based tumor type 'cancer of unknown primary prediction algorithm' (CUPPA) was developed based on previously described principles and validated on a large pan-cancer WGS database of metastatic cancer patients (>4000 samples) and 254 independent patients, respectively. We assessed the clinical value of this prediction algorithm as part of routine WGS-based diagnostic work-up for 72 CUP patients. RESULTS: CUPPA correctly predicted the primary tumor type in 78% of samples in the independent validation cohort (194/254 patients). High-confidence predictions (>95% precision) were obtained for 162/254 patients (64%). When integrated in the diagnostic work-up of CUP patients, CUPPA could identify a primary tumor type for 49/72 patients (68%). Most common diagnoses included non-small-cell lung (n = 7), gastroesophageal (n = 4), pancreatic (n = 4), and colorectal cancer (n = 3). Actionable events with matched therapy options in clinical trials were identified in 47% of patients. CONCLUSIONS: Genome-based tumor type prediction can predict cancer diagnoses with high accuracy when integrated in the routine diagnostic work-up of patients with metastatic cancer. With identification of the primary tumor type in the majority of patients and detection of actionable events, WGS is a valuable diagnostic tool for patients with CUP.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Neoplasias Primárias Desconhecidas , Humanos , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/genética , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Genômica , Sequenciamento Completo do Genoma
5.
BMC Cancer ; 22(1): 1299, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36503495

RESUMO

BACKGROUND: Many screening programs for colorectal cancer (CRC) use the fecal immunochemical test (FIT) to triage individuals for colonoscopy. Although these programs reduce CRC incidence and CRC-related mortality, the detection of advanced precursor lesions (advanced adenomas and advanced serrated polyps) by FIT could be improved. As an alternative for FIT, the antibody-based multitargetFIT (mtFIT) has been proposed. The mtFIT measures three protein markers: hemoglobin, calprotectin, and serpin family F member 2. In a retrospective diagnostic accuracy study in a large colonoscopy-controlled series (n = 1284), mtFIT showed increased sensitivity for advanced neoplasia (AN), at equal specificity, compared to FIT (42.9% versus 37.3%; p = 0.025). This increase was mainly due to a higher sensitivity of mtFIT for advanced adenomas (37.8% versus 28.1% for FIT; p = 0.006). The present mtFIT study aims to prospectively validate these findings in the context of the Dutch national CRC screening program. METHOD: The mtFIT study is a cross-sectional intervention study with a paired design. Eligible subjects for the Dutch FIT-based national CRC screening program are invited to perform mtFIT in addition to FIT. Samples are collected at home, from the same bowel movement, and are shipped to a central laboratory by postal mail. If either one or both tests are positive, participants are referred for colonoscopy. Detailed colonoscopy and pathology data are centrally stored in a national screening database (ScreenIT; Topicus, Deventer, the Netherlands) that is managed by the screening organization, and will be retrieved for this study. We aim to determine the relative sensitivity for AN, comprising of CRC, advanced adenomas and advanced serrated polyps, of mtFIT compared to FIT at an equal positivity rate. Additionally, we will use the Adenoma and Serrated Pathway to Colorectal CAncer model to predict lifetime health effects and costs for programmatic mtFIT- versus FIT-based screening. The target sample size is 13,131 participants. DISCUSSION: The outcome of this study will inform on the comparative clinical utility of mtFIT versus FIT in the Dutch national CRC screening program and is an important step forward in the development of a new non-invasive stool test for CRC screening. TRIAL REGISTRATION: Clinicaltrials.gov ; NCT05314309, registered April 6th 2022, first inclusions March 25th 2022 https://clinicaltrials.gov/ct2/results?cond=&term=NCT05314309&cntry=&state=&city=&dist =.


Assuntos
Adenoma , Neoplasias Colorretais , Pólipos , Humanos , Adenoma/diagnóstico , Adenoma/patologia , Colonoscopia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Estudos Transversais , Detecção Precoce de Câncer/métodos , Fezes/química , Hemoglobinas/análise , Programas de Rastreamento/métodos , Sangue Oculto , Estudos Retrospectivos
6.
Trials ; 23(1): 913, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307892

RESUMO

BACKGROUND: Disease recurrence is the main cause of mortality after resection of pancreatic ductal adenocarcinoma (PDAC). In 20-30% of resected patients, isolated local PDAC recurrence occurs. Retrospective studies have suggested that stereotactic body radiation therapy (SBRT) might lead to improved local control in these patients, potentially having a beneficial effect on both survival and quality of life. The "nationwide randomized controlled trial on additional treatment for isolated local pancreatic cancer recurrence using stereotactic body radiation therapy" (ARCADE) will investigate the value of SBRT in addition to standard of care in patients with isolated local PDAC recurrence compared to standard of care alone, regarding both survival and quality of life outcomes. METHODS: The ARCADE trial is nested within a prospective cohort (Dutch Pancreatic Cancer Project; PACAP) according to the 'Trials within Cohorts' design. All PACAP participants with isolated local PDAC recurrence after primary resection who provided informed consent for being randomized in future studies are eligible. Patients will be randomized for local therapy (5 fractions of 8 Gy SBRT) in addition to standard of care or standard of care alone. In total, 174 patients will be included. The main study endpoint is survival after recurrence. The most important secondary endpoint is quality of life. DISCUSSION: It is hypothesized that additional SBRT, compared to standard of care alone, improves survival and quality of life in patients with isolated local recurrence after PDAC resection. TRIAL REGISTRATION: ClinicalTrials.gov registration NCT04881487 . Registered on May 11, 2021.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Radiocirurgia , Humanos , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Estudos Prospectivos , Qualidade de Vida , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Recidiva Local de Neoplasia/patologia , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/cirurgia , Carcinoma Ductal Pancreático/radioterapia , Carcinoma Ductal Pancreático/cirurgia , Neoplasias Pancreáticas
7.
J Chem Phys ; 157(7): 074305, 2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-35987578

RESUMO

In this work, we explore the role of chemical reactions on the properties of buffer gas cooled molecular beams. In particular, we focus on scenarios relevant to the formation of AlF and CaF via chemical reactions between the Ca and Al atoms ablated from a solid target in an atmosphere of a fluorine-containing gas, in this case, SF6 and NF3. Reactions are studied following an ab initio molecular dynamics approach, and the results are rationalized following a tree-shaped reaction model based on Bayesian inference. We find that NF3 reacts more efficiently with hot metal atoms to form monofluoride molecules than SF6. In addition, when using NF3, the reaction products have lower kinetic energy, requiring fewer collisions to thermalize with the cryogenic helium. Furthermore, we find that the reaction probability for AlF formation is much higher than for CaF across a broad range of kinetic temperatures.

8.
J Chem Phys ; 156(18): 184301, 2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35568560

RESUMO

Aluminum monofluoride (AlF) possesses highly favorable properties for laser cooling, both via the A1Π and a3Π states. Determining efficient pathways between the singlet and the triplet manifold of electronic states will be advantageous for future experiments at ultralow temperatures. The lowest rotational levels of the A1Π, v = 6 and b3Σ+, v = 5 states of AlF are nearly iso-energetic and interact via spin-orbit coupling. These levels thus have a strongly mixed spin-character and provide a singlet-triplet doorway. We here present a hyperfine resolved spectroscopic study of the A1Π, v = 6//b3Σ+, v = 5 perturbed system in a jet-cooled, pulsed molecular beam. From a fit to the observed energies of the hyperfine levels, the fine and hyperfine structure parameters of the coupled states and their relative energies as well as the spin-orbit interaction parameter are determined. The standard deviation of the fit is about 15 MHz. We experimentally determine the radiative lifetimes of selected hyperfine levels by time-delayed ionization, Lamb dip spectroscopy, and accurate measurements of the transition lineshapes. The measured lifetimes range between 2 and 200 ns, determined by the degree of singlet-triplet mixing for each level.

9.
J Chem Phys ; 156(13): 134301, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35395882

RESUMO

We report on hyperfine-resolved laser spectroscopy of the A2Π â† X2Σ+ transition of magnesium monofluoride (MgF), relevant for laser cooling. We recorded 25 rotational transitions with an absolute accuracy of better than 20 MHz, assigned 56 hyperfine lines, and determined precise rotational, fine, and hyperfine structure parameters for the A2Π state. The radiative lifetime of the A2Π state was determined to be 7.2(3) ns, in good agreement with ab initio calculations. The transition isotope shift between bosonic isotopologues of the molecule is recorded and compared to predicted values within the Born-Oppenheimer approximation. We measured the Stark effect of selected rotational lines of the A2Π â† X2Σ+ transition by applying electric fields of up to 10.6 kV cm-1 and determined the permanent electric dipole moments of 24MgF in its ground X2Σ+ and first excited A2Π states to be µX = 2.88(20) D and µA = 3.20(22) D, respectively. Based on these measurements, we caution for potential losses from the optical cycling transition due to electric field induced parity mixing in the excited state. In order to scatter 104 photons, the electric field must be controlled to below 1 V cm-1.

10.
J Chem Phys ; 156(12): 124306, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35364883

RESUMO

Spectroscopic studies of aluminum monofluoride (AlF) have revealed its highly favorable properties for direct laser cooling. All Q lines of the strong A1Π â† X1Σ+ transition around 227 nm are rotationally closed and thereby suitable for the main cooling cycle. The same holds for the narrow, spin-forbidden a3Π â† X1Σ+ transition around 367 nm, which has a recoil limit in the µK range. We here report on the spectroscopic characterization of the lowest rotational levels in the a3Π state of AlF for v = 0-8 using a jet-cooled, pulsed molecular beam. An accidental AC Stark shift is observed on the a3Π0, v = 4 ← X1Σ+, v = 4 band. By using time-delayed ionization for state-selective detection of the molecules in the metastable a3Π state at different points along the molecular beam, the radiative lifetime of the a3Π1, v = 0, J = 1 level is experimentally determined as τ = 1.89 ± 0.15 ms. A laser/radio frequency multiple resonance ionization scheme is employed to determine the hyperfine splittings in the a3Π1, v = 5 level. The experimentally derived hyperfine parameters are compared to the outcome of quantum chemistry calculations. A spectral line with a width of 1.27 kHz is recorded between hyperfine levels in the a3Π, v = 0 state. These measurements benchmark the electronic potential of the a3Π state and yield accurate values for the photon scattering rate and for the elements of the Franck-Condon matrix of the a3Π-X1Σ+ system.

11.
Clin Transl Radiat Oncol ; 34: 82-89, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35372703

RESUMO

Purpose: This R-Ideal stage 1b/2a study describes the workflow and feasibility of long-course fractionated online adaptive MR-guided chemoradiotherapy with reduced CTV-to-PTV margins on the 1.5T MR-Linac for patients with esophageal cancer. Methods: Patients with esophageal cancer scheduled to undergo chemoradiation were treated on a 1.5T MR-Linac. Daily MR-images were acquired for online contour adaptation and replanning. Contours were manually adapted to match the daily anatomy and an isotropic CTV-to-PTV margin of 6 mm was applied. Time was recorded for all individual steps in the workflow. Feasibility and patient tolerability were defined as on-table time of ≤60 min and completion of >95% of the fractions on the MR-Linac, respectively. Positioning verification and post-treatment MRIs were retrospectively analyzed and dosimetric parameters were compared to standard non-adaptive conventional treatment plans. Results: Nine patients with esophageal cancer were treated with chemoradiation; eight patients received 41.4 Gy in 23 fractions and one received 50.4 Gy in 28 fractions. Four patients received all planned fractions on the MR-Linac, whereas for two patients >5% of fractions were rescheduled to a conventional linac for reasons of discomfort. A total of 183 (86%) of 212 scheduled fractions were successfully delivered on the MR-Linac. Three fractions ended prematurely due to technical issues and 26 fractions were rescheduled on a conventional linac due to MR-Linac downtime (n = 10), logistical reasons (n = 3) or discomfort (n = 13).The median time per fraction was 53 min (IQR = 3 min). Daily adapted MR-Linac plans had similar target coverage, whereas dose to the organs-at-risk was significantly reduced compared to conventional treatment (26% and 12% reduction in mean lung and heart dose, respectively). Conclusion: Daily online adaptive fractionated chemoradiotherapy with reduced PTV margins is moderately feasible for esophageal cancer and results in better sparing of heart and lungs. Future studies should focus on further optimization and acceleration of the current workflow.

12.
Ned Tijdschr Tandheelkd ; 129(4): 169-173, 2022 Apr.
Artigo em Holandês | MEDLINE | ID: mdl-35420274

RESUMO

While abroad, a healthy 36-year-old woman slammed head-on into a rock wall at high speed, resulting in significant facial trauma. The initial trauma care and first aid took place abroad. In the Netherlands, the woman was referred to the Department of Oral and Maxillofacial Surgery (OMFS) for reconstruction of her face and alveolar processes, gingiva and dentition. In view of the seriousness of the injuries, a 3D treatment plan was drawn up in a multidisciplinary collaboration with an OMF surgeon, an implantologist, dentist and dental technician. By making a digital setup of both the top and bottom front in advance, it was possible to work predictably. The first step consisted of bone augmentation by means of an iliac crest graft to reconstruct the major bone defects of the superior and inferior alveolar processes. Implants were then placed in the upper and lower jaws in the ideal position for the suprastructure by means of drill jigs. Within 10 months after the trauma, the implant bridges could be placed on individual zirconia frameworks to optimally restore oral function and aesthetics, completing the reconstruction.


Assuntos
Implantes Dentários , Adulto , Processo Alveolar , Transplante Ósseo/métodos , Implantação Dentária Endóssea/métodos , Feminino , Gengiva/cirurgia , Humanos , Mandíbula/cirurgia
13.
Int J Oral Maxillofac Surg ; 51(2): 263-268, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33933335

RESUMO

The aim of this study was to evaluate a novel soft tissue-based method to register an intraoral scan (IOS) with a cone beam computed tomography (CBCT) scan. IOS and CBCT data were obtained from eight dentate patients (mean age 21±2 years; three male, five female) and 14 fully edentulous patients (mean age 56±9 years; eight male, six female). An algorithm was developed to create a soft tissue model of the CBCT scan, which allowed a soft tissue-based registration to be performed with the IOS. First, validation was performed on dentate jaws with registration of the palatal mucosal surface and accuracy evaluation at the level of the teeth. Second, fully edentulous jaws were registered using both the palatal and alveolar crest mucosal surfaces. Distance maps were created to measure the method accuracy. The mean registration error was 0.49±0.26mm for the dentate jaws. Registration of the fully edentulous jaws had a mean error of 0.16±0.08mm at the palate and 0.16±0.05mm at the alveolar crest. In conclusion, the high accuracy of this registration method may allow the digital workflow to be optimized when no teeth are available to perform a regular registration procedure.


Assuntos
Arcada Edêntula , Boca Edêntula , Adulto , Idoso , Algoritmos , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Imageamento Tridimensional , Arcada Edêntula/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Ned Tijdschr Tandheelkd ; 128(9): 423-428, 2021 Sep.
Artigo em Holandês | MEDLINE | ID: mdl-34490766

RESUMO

In publications, implant retained overdentures have frequently been suggested to be a cost-efficient treatment alternative to conventional dentures. But whether the additional health benefits of implant retained overdentures even out the higher costs is not answered unequivocally. The qualification of the improved quality of life and the valuation of costs are strongly determined by the decision maker (insurance and/or patient). Future research must be encouraged to further elucidate patient willingness to pay for implant retained overdentures and the societal return on investment herein more generally.


Assuntos
Implantes Dentários , Revestimento de Dentadura , Prótese Dentária Fixada por Implante , Retenção de Dentadura , Humanos , Mandíbula , Satisfação do Paciente , Qualidade de Vida
15.
Radiother Oncol ; 161: 16-22, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33992628

RESUMO

PURPOSE: This study aimed to assess the smallest clinical target volume (CTV) to planned target volume (PTV) margins for esophageal cancer radiotherapy using daily online registration to the bony anatomy that yield full dosimetric coverage over the course of treatment. METHODS: 29 esophageal cancer patients underwent six T2-weighted MRI scans at weekly intervals. An online bone-match image-guided radiotherapy treatment of five fractions was simulated for each patient. Multiple conformal treatment plans with increasing margins around the CTV were created for each patient. Then, the dose was warped to obtain an accumulated dose per simulated fraction. Full target coverage by 95% of the prescribed dose was assessed as a function of margin expansion in six directions. If target coverage in a single direction was accomplished, then the respective margin remained fixed for the subsequent dose plans. Margins in uncovered directions were increased in a new dose plan until full target coverage was achieved. RESULTS: The smallest set of CTV-to-PTV margins that yielded full dosimetric CTV coverage was 8 mm in posterior and right direction, 9 mm in anterior and cranial direction and 10 mm in left and caudal direction for 27 out of 29 patients. In two patients the curvature of the esophagus considerably changed between fractions, which required a 17 and 23 mm margin in right direction. CONCLUSION: Accumulated dose analysis revealed that CTV-to-PTV treatment margins of 8, 9 and 10 mm in posterior & right, anterior & cranial and left & caudal direction, respectively, are sufficient to account for interfraction tumor variations over the course of treatment when applying a daily online bone match. However, two patients with extreme esophageal interfraction motion were insufficiently covered with these margins and were identified as patients requiring replanning to achieve full target coverage.


Assuntos
Neoplasias Esofágicas , Neoplasias da Próstata , Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Neoplasias Esofágicas/radioterapia , Humanos , Masculino , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
16.
Int J Oral Maxillofac Surg ; 50(11): 1521-1528, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33642151

RESUMO

Although the functional benefits of implants in the rehabilitation of edentulous cancer patients are well-known, most studies report on postponed implant placement. The outcome of immediate implant placement regarding successful rehabilitation, implant loading and survival is unclear. Two hundred and seven edentulous oral cancer patients that received implants during ablative surgery at the Radboud University Medical Centre between 2000 and 2011 were included. Data regarding the oncological treatment, implant placement, follow-up and prosthodontic rehabilitation were recorded retrospectively with a follow-up period of 5-17 years. Functioning implant-retained dentures were made in 73.9% of the patients. Of the surviving patients, 81.9% had functioning dentures after 2 years and 86.3% after 10 years. Patients with ASA score 1 and younger patients were rehabilitated more frequently. The median time of functioning denture placement was 336 days after surgery, with a negative influence of postoperative radiotherapy. Implant survival was 90.7%, and was lower when the implant was placed in a jaw involved in the tumour. Immediate implant placement during oral cancer surgery led to a high number of edentulous patients rehabilitated with implant-retained dentures, which are placed at an early time.


Assuntos
Implantes Dentários , Carga Imediata em Implante Dentário , Arcada Edêntula , Neoplasias Bucais , Implantação Dentária Endóssea , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Seguimentos , Humanos , Arcada Edêntula/cirurgia , Neoplasias Bucais/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
17.
Int J Oral Maxillofac Surg ; 50(9): 1249-1258, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33589294

RESUMO

The aim of this study was to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing the outcomes of short dental implants (≤7mm) versus vertical bone augmentation followed by regular dental implants (>7mm) in the deficient posterior mandible. In total, eight RCTs (six using interpositional sandwich grafting and two using a guided bone regeneration technique) were reported in 17 articles at different time points. In the meta-analysis of the sandwich group, the relative risk (RR) for implant loss at 1year was in favour of short implants (RR 0.41, P=0.02), while no significant difference was found at 3 years (RR 0.65, P=0.43), 5 years (RR 1.08, P=0.86), or 8 years (RR 1.53, P=0.52). The risk of complications was in favour of short implants (RR 0.34, P=0.0002), as was the mean difference in marginal bone resorption after 1 year (-0.09mm, P=0.17), 3 years (-0.32mm, P<0.00001), 5 years (-0.65mm, P<0.00001), and 8 years (-0.88, P<0.00001). The mean residual osseointegration length of the implants was between 2.94mm and 4.44mm in the short implants group and between 7.97mm and 8.62mm in the regular implants group after 5 years. In conclusion, in the deficient atrophic posterior mandible, short implants and regular implants demonstrate comparable outcomes within the first 5 years. Patients who are fit for surgery should be informed about the risks and benefits of both options.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Regeneração Óssea , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Humanos , Mandíbula/cirurgia , Osseointegração
18.
Int J Oral Maxillofac Surg ; 50(1): 38-42, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32593512

RESUMO

Monitoring vascular perfusion of transferred tissue is essential in reconstructive surgery to recognize early flap failure. The aim of this study was to evaluate the ability of a digital surface scanner to detect vascular perfusion disorders through the monitoring of skin colour changes. A total of 160 surface scans of the forearm skin were performed with a TRIOS 3D scanner. Vascular compromise was simulated at different time-points by intermittent occlusion of the blood supply to the forearm skin (first the arterial blood supply and then the venous blood supply). Skin colour changes were examined according to the hue, saturation, and value colour scale. Colour differences were analysed with a paired t-test. Significant differences were observed between the colour of the normal skin and that of the vascular compromised skin (P<0.01). The surface scanner could distinguish between arterial occlusion and venous congestion (P<0.01). A digital surface scan is an objective, non-invasive tool to detect early vascular perfusion disorders of the skin.


Assuntos
Procedimentos de Cirurgia Plástica , Retalhos Cirúrgicos , Antebraço/cirurgia , Humanos , Perfusão , Veias
19.
Int J Oral Maxillofac Surg ; 50(2): 273-276, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32674903

RESUMO

For decades, hyperbaric oxygen (HBO) has often been part of the treatment of osteoradionecrosis (ORN), despite controversy in the literature about its efficacy. An online survey was conducted to investigate the use of HBO in the treatment of ORN by Dutch oral and maxillofacial surgeons and to assess their perception of its efficacy. Of the 53 Dutch oral and maxillofacial surgery units contacted, 49 (92%) replied. Thirty-five were not head and neck cancer (HNC) units or preferred partner (PP-HNC) units recognized by the Dutch Head and Neck Association. All HNC and PP-HNC units (group 1) treated ORN patients, compared to only 12 (34%) of the non-HNC units (group 2). The average number of ORN patients seen and treated was higher in group 1. The units in group 1 more often referred patients for HBO therapy (HBOT) than those in group 2 (93% vs 84%). The efficacy of HBOT in curing ORN, rated on a scale of 1 to 5 points, was 3.7 in group 1 and 3.2 in group 2. This survey shows a trend towards centralization of ORN care to more experienced units. These units tend to use HBOT in curing ORN.


Assuntos
Neoplasias de Cabeça e Pescoço , Oxigenoterapia Hiperbárica , Osteorradionecrose , Humanos , Cirurgiões Bucomaxilofaciais , Osteorradionecrose/terapia , Inquéritos e Questionários
20.
Ann Surg Oncol ; 28(5): 2730-2738, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33341917

RESUMO

BACKGROUND: Patients  with esophageal cancer  that invades adjacent structures (cT4b) are precluded from surgery and usually treated with definitive chemoradiotherapy (dCRT). dCRT might result in sufficient downstaging to enable a radical resection, possibly improving survival. This study aimed to assess the perioperative and oncologic outcomes of a salvage robot-assisted minimally invasive esophagectomy (RAMIE) in patients with cT4b esophageal cancer after dCRT. METHODS: Between June 2012 and November 2019, patients who underwent a RAMIE with a gastric conduit reconstruction after completion of dCRT for cT4b esophageal carcinoma were identified from a prospectively maintained surgical database at the University Medical Center Utrecht. RESULTS: In total, 24 patients with a histopathologically confirmed T4b adenocarcinoma or squamous cell carcinoma of the esophagus were included. The adjacent organs involved were the tracheobronchial tree (67%), aorta (21%) or both (13%). No conversions or major intraoperative complications were observed. A radical resection was achieved in 22 patients (92%), and a pathologic complete response was observed in 13 (54%) patients. Postoperative grade 2 or higher complications occurred in 20 patients (83%). The disease-free survival at 24 months was 68% for the patients in whom a radical resection was achieved. CONCLUSION: In patients with cT4b esophageal cancer treated with dCRT followed by a salvage RAMIE, a radical resection rate of 92% was achieved, with acceptable complications and promising survival rates. These results demonstrate the feasibility of a curative surgical treatment for patients with initially irresectable esophageal cancer but underscore the importance of a proper preoperative patient selection.


Assuntos
Boehmeria , Neoplasias Esofágicas , Robótica , Quimiorradioterapia , Neoplasias Esofágicas/cirurgia , Esofagectomia , Humanos , Terapia de Salvação , Resultado do Tratamento
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