Slow Expansion Research Articles

Modified transpalatal arch: An effective slow expansion and multi-utility appliance—A clinical pearl

Modified transpalatal arch: An effective slow expansion and multi-utility appliance—A clinical pearl

Stability of palatal rugae after orthodontic/orthopaedic expansion: a scoping review

Abstract Objective The palatal rugae are connective tissue located in the anterior third of the hard palate and present asymmetrically on each side of the palatine raphe. The stability and individualistic features of the palatal rugae have been suggested as an alternative human identification method in forensic medicine. However, there are different views about the tissue’s stability and reliability in individuals undergoing orthodontic expansion, as the palatal mucosa is stretched which likely alters palatal rugal morphology. The present review aims to summarise the available evidence regarding the stability of the palatal rugae after orthodontic expansion. Method Following the PRISMA-Scr guidelines, an extensive search was conducted using three databases (PubMed, Web of Science, and Scopus). Only studies that had control groups were included to allow for comparison. Results A total of six studies were identified. One report did not mention the type of expansion used, another used slow maxillary expansion (SME), and the other four used rapid maxillary expansion (RME). The results related to rugal length, morphological shape, and root mean square were inconclusive, likely because of data heterogeneity in expansion mechanics, the age of inclusion, and measurement outcomes. Conclusion More high-quality research is needed to substantiate the importance of palatal rugae in forensic medicine.

The relationship between morphological changes and oral function before and after slow palate expansion

ABSTRACT Purpose Recent reports indicate that Japanese children have narrow dental arches with weakening oral functions. Therefore, this study investigated the relationship between palatal morphology and oral function after expansion treatment with a slow, removable expansion appliance. Materials and Methods We evaluated changes in the deep, middle, and shallow palatal widths of 22 children with narrow dental arches who visited our hospital. We also assessed the tongue raising force, maximum occlusal force, lip closure force, and masticatory movement patterns, representing the oral function. Changes in the hyoid and resting tongue position before and after treatment were also evaluated using lateral cephalometric radiographs. Finally, the patients were divided into two groups based on the expansion frequency (once every two weeks or once per week) for measurement comparisons. Results We found that the amount of expansion at the deep width of the palate was half that at the shallow width. Furthermore, the maximum occlusal force and tongue raising forces improved after the treatment. Additionally, multiple regression analysis indicated that the resting tongue position and maximum occlusal force before the expansion treatment were significantly associated with the amount of palate expansion. Conclusions Slow plate expand can expansion the basal palate. Moreover, oral function improves after expansion therapy.

Sustainable development with city, industry, economic and environment: The role of city-industry integration on green economic growth

<p>In order to avoid the real economy development lags behind and the deterioration of ecological problems in the process of traditional urbanization, China has been promoting city-industry deep integration, but the connection between city-industry integration and green economic growth, especially the spatial effect, has not been systematically explained. Based on the panel data from 2007 to 2018, this paper constructs an evaluation index system and uses the SEEA method to measure city-industry integration (CII) level and green economy growth (GEG) level. Then, by employing spatial Durbin model and intermediary effect model, it further systematically investigates the spatial impact of CII on GEG and the potential mechanism. The study found that: (1) On the whole, CII shows “slow-steady integration” trend, but regional heterogeneity was obvious and accompanied by “slow gap expansion”. GEG experienced “sharp increase” with “polarization” characteristic. (2) CII can directly promote regional GEG (with a marginal effect of 0.689), more effectively than traditional urbanization, and CII has obvious spatial spillover effects on GEG in both “local effect” and “neighboring effect”. (3) Interestingly, technological innovation and consumption structure upgrading are significant mediating mechanisms. (4) The direct positive effect of CII shows the regional imbalance characteristic. Finally, the corresponding policy implications are put forward.</p>

Double-edged sword of diabetes mellitus for abdominal aortic aneurysm.

Diabetes mellitus (DM) has been proved to contribute to multiple comorbidities that are risk factors for abdominal aortic aneurysm (AAA). Remarkably, evidences from epidemiologic studies have demonstrated a negative association between the two disease states. On the other hand, hyperglycemic state was linked to post-operative morbidities following AAA repair. This review aims to provide a thorough picture on the double-edged nature of DM and major hypoglycemic medications on prevalence, growth rate and rupture of AAA, as well as DM-associated prognosis post AAA repair. We performed a comprehensive search in electronic databases to look for literatures demonstrating the association between DM and AAA. The primary focus of the literature search was on the impact of DM on the morbidity, enlargement and rupture rate, as well as post-operative complications of AAA. The role of antidiabetic medications was also explored. Retrospective epidemiological studies and large database researches associated the presence of DM with decreased prevalence, slower expansion and limited rupture rate of AAA. Major hypoglycemic drugs exert similar protective effect as DM against AAA by targeting pathological hallmarks involved in AAA formation and progression, which were demonstrated predominantly by animal studies. Nevertheless, presence of DM or postoperative hyperglycemia was linked to poorer short-term and long-term prognosis, primarily due to greater risk of infection, longer duration of hospital stays and death. While DM is a positive factor in the formation and progression of AAA, it is also associated with higher risk of negative outcomes following AAA repair. Concomitant use of antidiabetic medications may contribute to the protective mechanism of DM in AAA, but further studies are still warranted to explore their role following AAA repair.

Numerical Simulation Study of ground surface subsidence caused by filling mining on surface buildings and facilities in a mining area: a case study

The filling mining method is planned to be adopted in Chentaigou Iron Mine. There are many significant buildings and facilities in the mining area, making it necessary to evaluate the influences of underground mining on the surface buildings and facilities. The main purpose of this research was to evaluate the extent of the surface subsidence basin and the degree of damage of buildings and facilities after filling mining by numerical simulation. To this end, a three-dimensional numerical model of the whole mining area was established. Secondly, a Discrete Fracture Network (DFN) in 3DEC numerical simulation software was adopted to obtain the strength parameters of each representative elemental volume (REV). Furthermore, FLAC3D numerical simulation software was utilized to evaluate the range of influence of the surface subsidence basin after filling mining. Finally, the maximum major principal strain on the surface was calculated. The results show that the surface subsidence basin of underground mining in this iron mine undergoes slow expansion then rapid expansion. Expansion of the surface subsidence basin is restricted by fault F1. After the mining orebody, the maximum major principal strain of surface meets design requirements, and the surface buildings and facilities are deemed safe.

Dimensional changes of upper airway after slow vs rapid miniscrew-supported maxillary expansion in adolescents: a cone-beam computed tomography study

BackgroundTo date, the effects of different activation rates of miniscrew-supported expanders on the airway have not been compared. Hence, the purpose of this retrospective study was to evaluate and compare the effects of slow and rapid miniscrew-supported maxillary expansion on the upper airway dimensions using cone-beam computed tomography (CBCT).MethodsData of 20 patients (Age 12 to 16 years old) treated using miniscrew-supported expanders at the Faculty of Dentistry, Alexandria University was collected. The patients were equally divided into two groups according to the activation protocol; slow maxillary expansion (SME): activation once every other day, and rapid maxillary expansion (RME): activation twice daily. CBCT scans obtained pre-expansion and 5 months post-expansion were used to evaluate the changes in the upper airway dimensions. Comparisons between the two time points within each group were done using paired samples t-test. SME and RME groups were compared using independent samples t-test. Significance level was set at p < 0.05.ResultsBoth groups showed a significant increase in anterior, middle, and posterior nasal cavity width. SME resulted in significantly greater increase of the anterior nasal cavity width than RME (Mean difference between the groups, 2.64 mm; 95% CI, 0.83, 4.45; p = 0.007). The dimensions of the retropalatal and retroglossal airways did not change significantly in either group. Both groups resulted in a significant increase of maxillary width, palatal width, and inter-molar width. RME showed a significantly larger increase of inter-molar width than SME (Mean difference between the groups, − 2.44 mm; 95% CI, − 3.88, − 1.00; p = 0.002).ConclusionsThe use of either a slow or rapid activation protocol is effective in expanding the nasomaxillary complex, with greater expansion achieved in the anterior section of the nasal cavity using the slow rate. However, the expander design employed in the current study does not affect the dimensions of the retropalatal or retroglossal airways.

A Novel Diffuse Plasma Jet Without Airflow and Its Application in the Real-Time Surface Modification of Titanium

Real-time modification is a promising method for improving the clinical surface performance of titanium (Ti) implants, which requires a simple structure, short treatment time, and long duration of hydrophilicity. Hence, a novel diffuse jet without airflow was developed in this paper to address these three requirements. The diffuse jet produces cone-shaped plasma with a maximum radial size of 16 mm and a typical characteristic of diffuse discharge. Due to the absence of airflow, the diffuse jet with a simple structure and a mild discharge meets the first requirement. The diffuse jet remains quasiuniform and stable when contacting with metals. The effective modification area is approximately 200 mm2, which is seven times larger than that of the current plasma jets. A super-hydrophilic surface with the original multilevel microporous structure can be obtained after just 40 s of treatment with the diffuse jet, and remain viable for at least 30 mins, which meets the other two requirements. The carbon-cleaning effect and oxygen-attaching effect of the diffuse jet, along with the higher intensities of the C = O/O-H together with the lower intensities of C-C/C-H after modifications, are responsible for the super-hydrophilicity. Because the slow expansion and the long reaction time of the active particles caused by the absence of airflow, a longer treatment time is more beneficial for the duration of the super-hydrophilicity. The results above successfully meet all the requirements and present a novel efficient method for the clinical real-time surface modification of Ti.

Surface explosion and subsequent core expansion of laser-heated clusters probed by time-resolved photoelectron spectroscopy

The dynamics of nanoplasma produced by an intense near-infrared pulse was investigated by time-resolved soft x-ray photoelectron spectroscopy. The pump-probe electron spectra indicate transient evolution of the electronic states of the constituent atoms and ions during plasma formation and disintegration. The delay dependence of photoelectron yields supports two-step fragmentation of laser-heated clusters, i.e., rapid explosion of surface ions followed by slow expansion of neutral atoms. The speed of the neutral core expansion was evaluated by comparing the experimental data with a model of uniform neutral core expansion.

Patient-reported outcomes of slow vs rapid miniscrew-supported maxillary expansion in adolescents: secondary outcomes of a randomized clinical trial.

To compare patient-reported experience between a Penn expander activated every other day vs twice daily. A total of 30 patients aged 12-16 years with transverse maxillary deficiency were recruited from the outpatient clinic, Faculty of Dentistry, Alexandria University (February 2019-December 2020). They were randomly allocated to two groups using block randomization (block size of six) and an allocation ratio of 1:1, which was concealed using opaque, sealed, sequentially numbered envelopes. Both groups received Penn expanders anchored by four palatal miniscrews. The slow maxillary expansion (SME) group activated the appliance once every other day. The rapid maxillary expansion (RME) group activated the appliance twice daily. Outcome measures were pain, pressure, headache, dizziness, speech difficulty, chewing difficulty, and swallowing difficulty scores rated by the participants on an 11-point numeric rating scale (NRS) at the following four time points: before appliance insertion (t1), after first activation (t2), after 1 week of activation (t3), and after last activation (t4). Data of 24 patients in the SME group (n = 12, mean age = 14.30 ± 1.37 years) and RME group (n = 12, mean age = 15.07 ± 1.59 years) were analyzed. Median scores for all outcomes were in the bottom quartiles of the NRS. No difference was found between the two groups at t1 or t2. Significantly higher scores for all variables, except dizziness and headache, were reported in the RME group at t4. Activation of miniscrew-supported expanders resulted in mild to moderate discomfort and functional limitation. Slow activation resulted in a better overall patient experience compared with rapid activation.

Experimental study on progressive deformation and failure mode of loess fill slopes under freeze-thaw cycles and earthquakes

Earthquakes and freeze-thaw cycles are two important causes of landslides, but knowledge of their combined effect is limited. Therefore, a freeze-thaw test and large-scale shaking table tests were carried out to simulate the progressive deformation and failure mode of loess fill slopes. The process of frost-heaving deformation and seismic deformation was observed, and the failure mode was analyzed by comparing with the accelerations. The results showed that the slope stability decreased after freeze-thaw cycles. Freezing and thawing causes the crest and upper portion melted, and settled to the lower portion, creating frost-heaving zones and irreversible cracks. Comparisons between the freezing-thawing slope and nonfreezing-thawing slope allowed to highlight, through the analysis of seismic responses, the possible and not negligible effect of both frost-heaving spatial distribution of slope surface soil and freeze-thaw interface during the seismic shaking in initiation and development of landslides. The peak ground acceleration (PGA) amplification factors of freezing-thawing slope were higher, especially in the frost-heaving zones. Cracks in freezing-thawing slope developed faster and deformation was greater. The freeze-thaw interface became a potential slip surface and a multistep landslide suddenly occurred under 1.2 g seismic loads, while the nonfreezing-thawing slope was stable. The freezing-thawing slope shows a brittle superficial shear failure, and its failure mode is freeze-thaw cycles - forming potential sliding surface and irreversible cracks - slow expansion of cracks - rapid development and penetration of cracks - superficial shear sliding.

Rapid maxillary expansion vs slow maxillary expansion in patients with cleft lip and/or palate: a systematic review and meta-analysis.

To compare the dentoalveolar outcomes of slow maxillary expansion (SME) and rapid maxillary expansion (RME) used for maxillary expansion before secondary alveolar bone grafting in patients with cleft lip and/or palate (CL/P). Secondarily, the advantages and disadvantages of SME vs RME were reviewed. A systematic search was conducted up to November 2021, including Medline (via PubMed), Embase (via Ovid), Web of Science, Cochrane Central, and Google Scholar. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Risk-of-bias assessment was performed using the Risk of Bias (RoB 2.0) and Risk Of Bias In Non-randomized Studies of Interventions (ROBINS I) tool. Overall quality was assessed using the Grading of Recommendations Assessment, Development, and Evaluation tool. Of 4007 records, five studies met the inclusion criteria. The randomized control trial (RCT) had a low risk of bias, the non-RCTs presented with a moderate risk of bias. Arch width and perimeter increased significantly with both SME and RME treatments. No difference in the increase in palatal depth was found. The meta-analysis showed a greater anterior-to-posterior expansion ratio for the Quad Helix (QH) appliance. The results for dental tipping were not conclusive. SME and RME promote equal posterior expansion in cleft patients. The anterior differential expansion is greater with SME (QH appliance). No clear evidence exists concerning the amount of dental adverse effects of SME and RME in cleft patients.

Slow expansion in orthodontics -A review article

One of the most common problems faced by an orthodontist while treating young as well as adult patients is the constricted maxillary arch. Expansion of the maxillary arch has been a topic of debate since centuries. The commonly used methods for constricted arch include slow maxillary expansion, rapid maxillary expansion and surgically assisted rapid palatal expansion (SARPE). Slow palatal expansion is a procedure to expand the maxillary arch in transverse dimension to correct the constricted maxillary arch with light forces. The following review article provides detailed information of various slow maxillary expansion appliances with their implications in orthodontics.

Evaluation of rapid versus slow maxillary expansion in early adolescent patients with skeletal maxillary constriction using cone-beam computed tomography: A short-term follow-up randomized controlled trial.

Maxillary expansion is one of the treatment options for the correction of the skeletal constriction of the upper jaw. However, evidence regarding the best treatment effects with the use of rapid vs. slow maxillary expansion in the early adolescence period (i.e., between the age of 12 and 16 years) is still lacking in the available literature. The aim of the present study was to investigate the effectiveness of rapid and slow maxillary expansion in treating posterior skeletal constriction, and to compare the 2 techniques in terms of skeletal and dentoalveolar changes by using cone-beam computed tomography (CBCT). The sample consisted of 34 patients (15 males and 19 females) suffering from posterior skeletal constriction. They were randomly allocated either to the rapid maxillary expansion (RME) group (17 patients aged 13.76 ±0.32 years) or to the slow maxillary expansion (SME) group (17 patients aged 14.02 ±0.28 years). The skeletal and dental landmarks, and changes in the posterior dimensions were examined using CBCT radiographs at the beginning of treatment (T1) and at the end of the observation period (T2). There were no significant differences between the 2 groups in terms of skeletal and dental changes except the amount of change in the inter-premolar width at the root apex, which was greater in the SME group (p = 0.007), as well as the amount of change in the skeletal palatal width in the molar region, which was also greater in the SME group (p = 0.008). Both maxillary expansion protocols were effective in treating posterior skeletal constriction. The average changes in the skeletal and dental widths were generally similar in both groups. Therefore, SME can be considered as an alternative to RME in patients with skeletal maxillary constriction in the early adolescence period.

Rapid maxillary expansion-A review

Maxillary expansion treatments have been used for more than a century to correct maxillary transverse deficiency. Three expansion treatment modalities are used today: rapid maxillary expansion (RME), slow maxillary expansion (SME) and surgically assisted maxillary expansion. Since each treatment modality has advantages and disadvantages, controversy regarding the use of each exists. Rapid Maxillary expansion or palatal expansion as it is sometimes called, occupies unique niche in dentofacial therapy. Rapid Maxillary expansion is a skeletal type of expansion that involves the separation of the mid-palatal suture and movement of the maxillary shelves away from each other.

Electroconversion synthesis of Ni/Co layered nanomaterials for high-performance supercapacitors

Ni/Co(OH) 2 nanosheets were prepared through an electroconversion reaction with CoCl 2 .6 H 2 O and NiCl 2 .6 H 2 O as raw materials and without an added structural guiding agent. NiCo 2 O 4 was obtained by calcination with Ni/Co(OH) 2 as a precursor. The structure and morphology of Ni/Co(OH) 2 and NiCo 2 O 4 were characterized by XRD, FTIR, XPS, and SEM. The characterization results show that the particle size range of Ni/Co(OH) 2 with a three-dimensional nanostructure is 10–84 nm, and it is formed by staggered stacking of nanosheets with a thickness of approximately 19 nm. The electrochemical test results show that the specific capacitance of the Ni/Co(OH) 2 nanosheet electrode in 1 M KOH electrolyte and 1 A/g current density is as high as 908.33 F/g, which can be attributed to its unique three-dimensional nanolayered structure, and as a result, more redox reaction active sites can be provided in the charge storage process. In addition, the structure of the Ni/Co(OH) 2 nanosheet electrode can slow down the volume change during the charge–discharge cycle and maintain the stability of the structure. Under the high current density of 10 A/g, the specific capacitance retention rate is 71% at 1500 cycles and 74% at 3500 cycles, but then it shows a downwards trend. The capacitance retention rate fluctuates between 60% and 30%. After 10000 cycles, the specific capacitance retention rate is still 30%, indicating that the electrode exhibits a good cycle performance. Ni/Co(OH) 2 and NiCo 2 O 4 nanosheets are successfully prepared by electroconversion-heat treatment method without adding a structural directing agent, which can be used as electrode materials for supercapacitors. The specific capacitance of the binder-free Ni/Co(OH) 2 nanosheet electrodes at a current density of 1 A/g in 1 M KOH electrolyte is 990.91 F/g. When the current density increases to 10 A/g, the specific capacitance of Ni/Co(OH) 2 nanosheet electrode can still reach 604.17 F/g. The specific capacitance retention rate is 71% at 1500 cycles and even increased to 74% at 3500 cycles. This work provides a facile and efficient synthesis strategy for surfactant-free preparation of three-dimensional nano hierarchical Ni/Co(OH) 2 electrode materials for high-performance supercapacitors. • Ni/Co(OH) 2 and NiCo 2 O 4 are prepared by electroconversion-heat treatment method without any structural directing agents. • Ni/Co(OH) 2 shows better electrochemical performance, with a specific capacitance of 990.91 F/g at 1 A/g. • The three-dimensional structure of Ni/Co(OH) 2 has a large specific surface area and small diffusion resistance, which can accelerate ion diffusion and electron transport, and slow down volume expansion.

Intrinsic blocking effect of FeSi alloy in LiPF6 electrolyte solutions

FeSi anode materials have attracted extensive attention because of their slow volume expansion. However, the side reactions between electrolytes and FeSi anodes have been neglected and rarely studied. In this work, the side reactions and corrosion kinetics of a FeSi alloy and LiPF6 electrolyte were elucidated using corrosion behavior analysis, electrochemical properties, and surface morphology, while the reaction mechanism was analyzed via X-ray photoelectron spectroscopy (XPS). The results show that the reaction rate of the FeSi alloy in the electrolyte decreases with an increase in silicon content and exposure time. The electrolyte transforms Fe (0) on the FeSi alloy interface into Fe (2+), which is further oxidized to Fe (3+). Finally, a fluoride film is deposited and accumulated on the alloy surface, which can prevent the LiPF6 electrolyte corroding the FeSi alloy matrix and prevent the occurrence of side reactions. Electrochemical tests show that the presence of a FeSi2 phase in the FeSi alloy can promote electron transmission, reduce impedance, and achieve a large reversible capacity (927.6 mAh·g−1) after 100 cycles. For lithium ion batteries, the FeSi alloy exhibits better cycle stability and a wider application market than those of the Si anode materials.

CBCT Analysis of Dento-Skeletal Changes after Rapid versus Slow Maxillary Expansion on Deciduous Teeth: A Randomized Clinical Trial.

The aim of the present study was to compare skeletal and dental changes after rapid maxillary expansion (RME) and slow maxillary expansion (SME) performed by a Leaf Expander (LE) with upper deciduous teeth as anchorage and using 3D CBCT (Cone Beam Computed Tomography) analysis. Mixed dentition patients were randomly divided in two groups, according to the different expansion used anchored on maxillary primary second molars: the RME group (n = 16) was treated with a Hyrax type expander, whereas the SME group (n = 16) was treated with an LE expander. CBCT scans were performed before (T1) and after treatment (T2) and analyzed with a custom landmarks system. A paired t-test was used for intragroup analysis between T1 and T2, and a Student t-test was used for intergroup analysis; statistical significance was set at 0.05. Both RME and SME groups showed a statistically significant increase in dental and skeletal diameters. Group comparisons between T1 and T2 showed a significant expansion rate in the RME group for upper permanent molars (p = 0.025) but not for deciduous molars (p = 0.790). Moreover, RME showed higher increases for skeletal expansion evaluated at nasal walls (p = 0.041), whereas at pterygoid plates did not show any significant differences compared with the SME group (p = 0.849). A significant transverse expansion could be achieved with the expander anchored on deciduous teeth. RME and SME produced effective both skeletal and dentoalveolar transverse expansion; RME produced more anterior expansion than SME but less control regarding the permanent molar decompensation. SME by LE therefore could be an efficient and helpful alternative in the treatment of transverse maxillary deficiency in growing patients.

Patterns in climate and seedling establishment at a dry tropical treeline

In some internal valleys of the northern Andes, precipitation at treeline elevation is seasonal, with one or two dry periods that could exert a strong control on tree seedling survival. However, little is known about (1) the severity of the dry periods, due to a lack of climate data, or (2) the effect of drought on tree seedling demographic dynamics and how this is modulated by local plant interactions in these tropical-alpine ecosystems. We studied annual precipitation variation and seedling demography and ecophysiology in relation to microclimate and neighboring plants in a dry treeline ecotone at 3100 m a.s.l in the Venezuelan Andes. We selected seedlings of the dominant tree species Cybianthus marginatus and Clusia multiflora at three sites, each with three adjacent 10 × 10-m plots within the forest, forest border, and páramo. For both species, seedling density was zero in the páramo and did not differ between border and forest. Growth rates were low for both species, but higher for Cybianthus in the border than in the forest. Survival rates were high in both environments. Low assimilation and transpiration rates were found in both species regardless of the environment. The spatial association of seedlings with moisture-regulating elements such as mosses, ferns and basal rosettes may indicate a benefit of better hydric conditions in their neighborhood. Our study shows a strong limitation for tree establishment in the páramo, but high rates of survival at the edge of the forest. This suggests a scenario of slow potential forest expansion at this tropical treeline, tree cover advancing in a closed front by the successive formation of forest-edge vegetation allowing tree seedling establishment outside of the forest.

Viscous Fingering Dynamics and Flow Regimes of Miscible Displacements in a Sealed Hele-Shaw Cell

Miscible viscous fingering occurs when a less viscous fluid displaces a more viscous one in porous media or a Hele–Shaw cell. Such flow instabilities are of particular interest in a variety of applications in flows and displacements in subsurface energy and environment systems. In this study, we investigate the miscible viscous fingering dynamics experimentally using water to displace glycerol in a sealed Hele–Shaw cell with two wells located in it instead of at the boundary or corners. We comprehensively examine the spatial and temporal variations of fingering dynamics, different flow regimes, and how they are affected by the water injection rate and control of pressure or rate at the outlet. Alongside the widely recognized diffusion-dominated and convection-dominated flow regimes, we identify three new regimes: a slow expansion regime prior to breakthrough, a rapid shrinkage regime immediately after breakthrough, and a uniform, slow expansion regime without fingering instability. Each regime is characterized by interesting flow dynamics, which has not been reported previously. The duration of each regime depends on the water injection rate and whether constant pressure or a constant production rate is applied at the outlet. The variations of swept area, interfacial length, and count of fingers are also quantitatively examined. This study provides new insights into the fundamental mechanisms for miscible fluid displacements in a variety of applications such as CO2 sequestration, hydrogen storage, enhanced oil recovery, and groundwater contaminate remediation.