scholarly journals Accuracy of 3-Dimensionally Printed Full-Arch Dental Models: A Systematic Review

2020 ◽  
Vol 9 (10) ◽  
pp. 3357 ◽  
Author(s):  
Yasaman Etemad-Shahidi ◽  
Omel Baneen Qallandar ◽  
Jessica Evenden ◽  
Frank Alifui-Segbaya ◽  
Khaled Elsayed Ahmed

The use of additive manufacturing in dentistry has exponentially increased with dental model construction being the most common use of the technology. Henceforth, identifying the accuracy of additively manufactured dental models is critical. The objective of this study was to systematically review the literature and evaluate the accuracy of full-arch dental models manufactured using different 3D printing technologies. Seven databases were searched, and 2209 articles initially identified of which twenty-eight studies fulfilling the inclusion criteria were analysed. A meta-analysis was not possible due to unclear reporting and heterogeneity of studies. Stereolithography (SLA) was the most investigated technology, followed by digital light processing (DLP). Accuracy of 3D printed models varied widely between <100 to >500 μm with the majority of models deemed of clinically acceptable accuracy. The smallest (3.3 μm) and largest (579 μm) mean errors were produced by SLA printers. For DLP, majority of investigated printers (n = 6/8) produced models with <100 μm accuracy. Manufacturing parameters, including layer thickness, base design, postprocessing and storage, significantly influenced the model’s accuracy. Majority of studies supported the use of 3D printed dental models. Nonetheless, models deemed clinically acceptable for orthodontic purposes may not necessarily be acceptable for the prosthodontic workflow or applications requiring high accuracy.

2021 ◽  
Vol 11 (13) ◽  
pp. 5994
Author(s):  
Li Hsin Lin ◽  
Joshua Granatelli ◽  
Frank Alifui-Segbaya ◽  
Laura Drake ◽  
Derek Smith ◽  
...  

The objective of this study was to propose a standardised methodology for assessing the accuracy of three-dimensional printed (3DP) full-arch dental models and the impact of storage using two printing technologies. A reference model (RM) comprising seven spheres was 3D-printed using digital light processing (MAX UV, MAX) and stereolithography (Form 2, F2) five times per printer. The diameter of the spheres (n = 35) represented the dimensional trueness (DT), while twenty-one vectors (n = 105) extending between the sphere centres represented the full-arch trueness (FT). Samples were measured at two (T1) and six (T2) weeks using a commercial profilometer to assess their dimensional stability. Significant (p < 0.05) contraction in DT occurred at T1 and T2 with a medium deviation of 108 µm and 99 µm for MAX, and 117 µm and 118 µm for F2, respectively. No significant (p > 0.05) deviations were detected for FT. The detected median deviations were evenly distributed across the arch for MAX at <50 µm versus F2, where the greatest error of 278 µm was in the posterior region. Storage did not significantly impact the model’s DT in contrast to FT (p < 0.05). The proposed methodology was able to assess the accuracy of 3DP. Storage significantly impacted the full-arch accuracy of the models up to 6 weeks post-printing.


2021 ◽  
Vol 10 (11) ◽  
pp. e344101113370
Author(s):  
Fernanda Latorre Melgaço Maia ◽  
Ademir Franco ◽  
Daphne Azambuja Hatschbach de Aquino ◽  
Luciana Butini Oliveira ◽  
José Luiz Cintra Junqueira ◽  
...  

This study aimed to assess the reproducibility of linear measurements performed in dental models produced via intraoral scanning and three-dimensional (3D) printing using digital light processing (DLP) and fused deposition modeling (FDM). A sample of 22 participants was selected for this study. Intraoral scanning was performed in each participant with TRIOS™ (3Shape A/S™, Copenhagen, Denmark) device. The digital models were 3D printed using DLP and FDM techniques. Using a caliper, intraoral linear measurements were performed in situ (on the surface of participant’s teeth) and on the 3D printed models. The measurements taken intraoral and on the models were compared using the Intraclass Correlation Coefficient (ICC). The correlation between measurements taken in situ and on DLP models was poor (<0.4), while between in situ and FDM it ranged from poor to satisfactory (<0.75). Generalized linear model showed that the differences did not reach statistically significant levels (p>0.05). According to Bland-Altman approach, the size of measurements did not bias the outcomes. The intraoral scanning and 3D printing techniques used in this study enabled the reproducibility of linear measurements, however, discrete distortions that might be clinically significant occurred.


2021 ◽  
Vol 11 (15) ◽  
pp. 6674
Author(s):  
Benjamin Alexander Ihssen ◽  
Robert Kerberger ◽  
Nicole Rauch ◽  
Dieter Drescher ◽  
Kathrin Becker

The aim of the present study was to investigate whether base height of 3D-printed dental models has an impact on local thickness values from polyethylene terephthalate glycol (PET-G) aligners. A total of 20 aligners were thermoformed on dental models from the upper jaw exhibiting either a 5 mm high (H) or narrow (N), i.e., 0 mm, base height. The aligners were digitized using micro-CT, segmented, and local thickness values were computed utilizing a 3D-distance transform. The mean thickness values and standard deviations were assessed for both groups, and local thickness values at pre-defined reference points were also recorded. The statistical analysis was performed using R. Aligners in group H were significantly thinner and more homogenous compared to group N (p < 0.001). Significant differences in thickness values were observed among tooth types between both groups. Whereas thickness values were comparable at cusp tips and occlusal/incisal/cervical measurement locations, facial and palatal surfaces were significantly thicker in group N compared to group H (p < 0.01). Within the limits of the study, the base height of 3D-printed models impacts on local thickness values of thermoformed aligners. The clinician should consider potential implication on exerted forces at the different tooth types, and at facial as well as palatal surfaces.


2019 ◽  
Vol 56 (4) ◽  
pp. 812-816
Author(s):  
Mihaela Pantea ◽  
Robert Ciocoiu ◽  
Ana Maria Cristina Tancu ◽  
Daniela-Mădălina Nină ◽  
Alexandru Petre ◽  
...  

The purpose of this study was to assess the accuracy of two 3D printed dental models manufactured after intraoral/IO and extraoral/EO scanning. A dental study model (KaVo Dental GmbH/Germany) was used as a reference for this research; this model was scanned with an industrial scanner (XT H 225 ST/Industrial CT scan/Nikon Metrology Inc./U.S.A.) and a reference STL file was generated (coded M1). Two 3D printed models (Form2/FormLabs Inc./U.S.A.) were produced via IO scanning (TRIOS 3 Battery Cart/3 Shape/Denmark), respectively via EO scanning (Swing Dental Scanner/Dof Inc./South Korea) of the reference dental model. The 3D printed models obtained were scanned with the industrial scanner, resulting in other two STL files (coded M2, respectively M3). All the STL files obtained (reference M1; M2; M3) were compared in pairs, using a 3D analysis software. Good results were achieved in obtaining 3D printed dental models via IO or EO scanning, yet, the 3D printed dental model obtained via IO scanning (M3) showed slightly improved dimensional compatibility with the reference model (M1) in comparison with the 3D printed dental model manufactured via EO scanning (M2).


2016 ◽  
Vol 51 (2) ◽  
pp. 72-82 ◽  
Author(s):  
John Elwood Romig ◽  
William J. Therrien ◽  
John W. Lloyd

We used meta-analysis to examine the criterion validity of four scoring procedures used in curriculum-based measurement of written language. A total of 22 articles representing 21 studies ( N = 21) met the inclusion criteria. Results indicated that two scoring procedures, correct word sequences and correct minus incorrect sequences, have acceptable criterion validity with commercially developed and state- or locally developed criterion assessments. Results indicated trends for scoring procedures at each grade level. Implications for researchers and practitioners are discussed.


2021 ◽  
Vol 10 (13) ◽  
pp. 2873
Author(s):  
Cornelia Melinda Adi Santoso ◽  
Fera Ketti ◽  
Taufan Bramantoro ◽  
Judit Zsuga ◽  
Attila Nagy

Emerging evidence has linked poor oral hygiene to metabolic syndrome (MetS), but previously, no summary of evidence has been conducted on the topic. This systematic review and meta-analysis aims to evaluate the associations of oral hygiene status and care with MetS. A systematic search of the PubMed and Web of Science databases from inception to March 17, 2021, and examination of reference lists was conducted to identify eligible observational studies. A random-effects model was applied to pool the effects of oral hygiene status and care on MetS. Thirteen studies met the inclusion criteria and had sufficient methodological quality. Good oral hygiene status (OR = 0.30 (0.13–0.66); I2 = 91%), frequent tooth brushing (OR = 0.68 (0.58–0.80); I2 = 89%), and frequent interdental cleaning (OR = 0.89 (0.81–0.99); I2 = 27%) were associated with a lower risk of MetS. Only one study examined the association between dental visits and MetS (OR = 1.10 (0.77–1.55)). Our findings suggested that there might be inverse associations of oral hygiene status, tooth-brushing frequency, and interdental cleaning with MetS. However, substantial heterogeneity for tooth-brushing frequency and inconsistent results for oral hygiene status in subgroup analyses were observed. There was insufficient evidence for the association between dental visits and MetS. Further longitudinal studies are needed to investigate these associations.


2021 ◽  
Vol 49 (7) ◽  
pp. 030006052110327
Author(s):  
Weihua Liu ◽  
Wenli Yu ◽  
Hongli Yu ◽  
Mingwei Sheng

Objective To compare the clinical efficacy and safety of dexmedetomidine and propofol in patients who underwent gastrointestinal endoscopy. Methods Relevant studies comparing dexmedetomidine and propofol among patients who underwent gastrointestinal endoscopy were retrieved from databases such as PubMed, Embase, and Cochrane Library. Results Seven relevant studies (dexmedetomidine group, n = 238; propofol group, n = 239) met the inclusion criteria. There were no significant differences in the induction time (weighted mean difference [WMD] = 3.46, 95% confidence interval [CI] = −0.95–7.88, I2 = 99%) and recovery time (WMD = 2.74, 95% CI = −2.72–8.19, I2 = 98%). Subgroup analysis revealed no significant differences in the risks of hypotension (risk ratio [RR] = 0.56, 95% CI = 0.25–1.22) and nausea and vomiting (RR = 1.00, 95% CI = 0.46–2.22) between the drugs, whereas dexmedetomidine carried a lower risk of hypoxia (RR = 0.26, 95% CI = 0.11–0.63) and higher risk of bradycardia (RR = 3.01, 95% CI = 1.38–6.54). Conclusions Dexmedetomidine had similar efficacy and safety profiles as propofol in patients undergoing gastrointestinal endoscopy.


Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 868
Author(s):  
Jorge Lorenzo Calvo ◽  
Xueyin Fei ◽  
Raúl Domínguez ◽  
Helios Pareja-Galeano

Cognitive functions are essential in any form of exercise. Recently, interest has mounted in addressing the relationship between caffeine intake and cognitive performance during sports practice. This review examines this relationship through a structured search of the databases Medline/PubMed and Web of Science for relevant articles published in English from August 1999 to March 2020. The study followed PRISMA guidelines. Inclusion criteria were defined according to the PICOS model. The identified records reported on randomized cross-over studies in which caffeine intake (as drinks, capsules, energy bars, or gum) was compared to an identical placebo situation. There were no filters on participants’ training level, gender, or age. For the systematic review, 13 studies examining the impacts of caffeine on objective measures of cognitive performance or self-reported cognitive performance were selected. Five of these studies were also subjected to meta-analysis. After pooling data in the meta-analysis, the significant impacts of caffeine only emerged on attention, accuracy, and speed. The results of the 13 studies, nevertheless, suggest that the intake of a low/moderate dose of caffeine before and/or during exercise can improve self-reported energy, mood, and cognitive functions, such as attention; it may also improve simple reaction time, choice reaction time, memory, or fatigue, however, this may depend on the research protocols.


2021 ◽  
Vol 49 (3) ◽  
pp. 030006052110023
Author(s):  
Qian Zou ◽  
Jiawei Si ◽  
Yatao Guo ◽  
Jiayu Yu ◽  
Huijuan Shi

Objective To determine the association between serum visfatin levels and psoriasis and to evaluate the correlation between serum visfatin levels and the severity of psoriasis. Methods The electronic databases PubMed®, Embase® and the Cochrane Library were searched for articles published from inception to 1 May 2020. Data were extracted and then standard mean differences (SMDs) and 95% confidence intervals (CIs) were calculated for pooled estimates. Results A total of 11 studies met the inclusion criteria and were included (448 patients diagnosed with psoriasis and 377 controls). This meta-analysis demonstrated that patients with psoriasis had significantly higher levels of visfatin than the controls (SMD = 0.90, 95% CI 0.52, 1.28). Subgroup analyses showed that differences in serum visfatin levels between the patient group and the control group were associated with ethnicity, Psoriasis Area and Severity Index (PASI) and body mass index. Additionally, a meta-analysis of correlations showed that visfatin levels in patients with psoriasis were positively correlated with PASI ( r = 0.51, 95% CI 0.14, 0.75). Conclusions This meta-analysis showed that serum visfatin levels in patients with psoriasis were significantly higher than those in the controls and a positive correlation between serum visfatin levels and psoriasis severity was observed.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
V McLaughlin ◽  
C Zhao ◽  
J.G Coghlan ◽  
L.S Chung ◽  
S.C Mathai ◽  
...  

Abstract Background CTD-PAH has historically represented a PAH subtype with poor prognosis. New therapies, as well as combination therapy approaches targeting multiple pathways have been approved for PAH based on RCTs. CTD-PAH patients comprise a subgroup of the RCT populations and efficacy analyses are based on subgroup analyses which can be less reliable than the overall analysis. We conducted a meta-analysis of RCTs of approved PAH therapies to evaluate outcomes of patients with CTD-PAH. Purpose To use meta-analysis to determine response to treatment in patients with CTD-PAH. Methods The PubMed and EMBASE databases were searched for English-only articles published between January 1, 2000 and November 25, 2019. Inclusion criteria were multicenter RCTs that enrolled adults with WHO group 1 pulmonary hypertension (PAH); enrollment in 2000 or later; long-term clinical morbidity and/or mortality event or 6-minute walk distance (6MWD) as an efficacy endpoint reported for ≥30 patients with CTD-PAH; and evaluation of a US Food and Drug Administration-approved PAH therapy. The primary outcomes were treatment effect as measured by the study time to first morbidity or morality event and change in 6MWD from baseline to between 3–6 months, per the data provided in each article. Results from individual studies were combined using a random-effects model for overall study population (PAH patients) and the subgroup of CTD-PAH patients. Results Ten RCTs (N=4329 PAH patients; n=1263 (29%) with CTD-PAH) met inclusion criteria and were included in the meta-analysis. At baseline, PAH patients had a mean age of 50 years, approximately 78% were female, and approximately 58% had functional class III or IV disease. These characteristics were balanced between treatment and control groups. Baseline 6MWD was 356 m for the overall population and 337 m for patients with CTD-PAH. Five RCTs (N=3172; n=941 with CTD-PAH [30%]) reported hazard ratios (HRs) for time to a morbidity or mortality event by drug treatment and PAH etiology: overall population HR=0.63 (95% confidence interval [CI], 0.56–0.72; P&lt;0.001); CTD-PAH population HR=0.64 (95% CI, 0.51–0.80; P&lt;0.001) (Figure). Nine RCTs reported mean change with drug treatment from baseline to 3 to 6 months in 6MWD for PAH and CTD patients: 33.9 m (95% CI, 21.9–45.9; P&lt;0.001) in the overall population; 20.2 m (95% CI, 10.8–29.7; P&lt;0.001) in CTD-PAH patients. Conclusions The improvement in 6MWD in patients with CTD-PAH is smaller than in those with other types of PAH, perhaps reflecting comorbidities and CTD-induced mobility constraints, independent of their cardiopulmonary capacity. Data from long term clinical morbidity/mortality endpoint studies in this large group of patients with CTD-PAH demonstrate that these patients derive significant benefit from currently available PAH therapies which, in many patients, comprised the addition of a drug targeting a second or third pathway involved in the pathophysiology of PAH. Treatment effect on morbidity/mortality Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Actelion Pharmaceuticals US, Inc.


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