Root Movement Research Articles

Summed Tissue Resistance of Periodontal Ligaments and Alveolar Bone in Orthodontic Distal Retraction of Maxillary Canines: Mathematical Simulation of Clinical Data and Interpretation of Results

Background: The mechanical properties of either alveolar bone or periodontal ligaments under orthodontic loading, as well as orthodontic tooth movement, have been studied in recent years using computational approaches. In previous studies, we developed a theoretical mathematical approach that uses a weighting coefficient of the summed resistance of periodontal structures, namely the bone and periodontal ligaments, in relation to apex movement, the center of rotation, orthodontic force loading, and time in order to quantify the biological response to orthodontic biomechanics. Methods: We analyzed the distal retraction of three maxillary canines and integrated the clinical data obtained in the previously developed mathematical programs. Results: The values of the (σ) weighting coefficient of the tissue resistance were interpreted in the context of the clinical data obtained: the smaller the value of (σ), the higher the actual tissue resistance, with a greater difference between the crown and root movement; also, the higher the value of (σ), the lower the actual tissue resistance, with a small difference between the crown and apex movement. Conclusions: The clinical interpretation of the results allows us to set a premise for the refinement of the mathematical programs so that we can use them in assessing the orthodontic biomechanics of larger patient groups over longer periods of time and create premises of treatment protocol simplification and adjustment.

Biomechanical analysis for the distalisation of the mandibular dentition with anterior alveolar bone loss based on the location of an applied force: A finite element study

Abstract Introduction The present study analysed the tooth movement patterns and stress distribution in patients presenting with anterior alveolar bone loss, associated with the use of force vectors applied from a mini-screw to distalise the mandibular dentition. Methods Mandibular anterior teeth characterised by alveolar bone loss (zero, one third, one half of the root length) were constructed from a cone-beam computed tomography image, and a mini-screw was inserted into the mandibular buccal shelf. A distalising force of 2 N was applied from the mini-screw to three different lengths of an anterior retraction hook: 2, 7, and 12 mm. The tooth displacement and von Mises stress distribution in the periodontal ligament (PDL) were calculated via a finite element analysis. Results In all the models, significant movement was found around the anterior segment, and the stress was primarily concentrated at the cervical margin and apical area of the lateral incisor and canine teeth. With absorption of the anterior alveolar bone, extrusive lingual inclination of the anterior teeth, intrusive distal tipping of the posterior teeth and stress concentration in the PDL increased. Long retraction hooks led to lingual root and intrusive crown movement of the incisors and reduced uncontrolled distal tipping movement of the posterior teeth but also increased the range and magnitude of stress in the PDL of the anterior teeth. Conclusion During the distalisation of the mandibular dentition associated with anterior alveolar bone horizontal resorption, different retraction hook heights may be selected to control the movement of the teeth. Special consideration should be given to stress in the PDL of the mandibular incisors.

Distalization of mandibular molar with iatrogenic root fracture in Class III malocclusion: a case report

BackgroundPlacement of interradicular orthodontic miniscrews poses a potential risk of root damage, including superficial root contact and root fracture. This case report describes the iatrogenic root-injured tooth movement of a 27-year-old male with skeletal Class III malocclusion as nonsurgical orthodontic treatment.Case presentationAn orthodontic miniscrew between the mandibular right first and second molars perforated the distal root of the mandibular first molar. A root fracture was discovered 4 months after miniscrew placement. Owing to the potential risk of ankylosis related to surgical intervention, a direct orthodontic distalizing force was applied towards the fractured distal root segment without additional treatment, resulting in considerable movement of the fractured tooth with maintaining tooth vitality. However, gradual root resorption of a fractured tooth with a separate root segment was observed. The mandibular arch distalization of skeletal Class III malocclusion was successfully performed and retained for 3 years 8 months with stable occlusion.ConclusionsThis case reveals a clinical remedy when root movement of a tooth with root fracture is indicated. The use of extra-alveolar miniscrews or miniplates can be considered for mandibular arch distalization to prevent potential root injuries caused by miniscrew placement.Clinical trial numberNot applicable.

Biomechanical effects of anew crimpable gate spring combined with conventional rectangular archwires for torque adjustment of individual anterior teeth : Acomparative finite element study.

Precise root torque adjustment of anterior teeth is indispensable for optimizing dental esthetics and occlusal stability in orthodontics. The efficiency of traditional rectangular archwire manipulation within bracket slots seems to be limited. The crimpable gate spring, anovel device, has emerged as apromising alternative. Yet, there is apaucity of guidelines for its optimal clinical application. This study used finite element analysis (FEA) to investigate the biomechanical impact of the gate spring on torque adjustment of individual anterior teeth and to elucidate the most effective application strategy. AFEA model was constructed by amaxillary central incisor affixed with an edgewise bracket featuring a0.022 × 0.028 inch (in) slot. Arange of stainless steel rectangular archwires, in conjunction with agate spring, were modeled and simulated within the bracket slots. Acontrol group utilized aconventional rectangular wire devoid of agate spring. Palatal root moments were standardized to 9, 18, and 36 Nmm for both experimental and control groups. The gate spring significantly amplified palatal root movement, notably with the 0.019 × 0.025 in archwire. However, this was accompanied by an increase in stress on the tooth and periodontal ligament, particularly in the cervical regions. The synergistic use of a0.019 × 0.025 in rectangular archwire with agate spring in a0.022 × 0.028 in bracket slot was identified as most efficacious for torque control of individual anterior teeth. The gate spring is aviable auxiliary device for enhancing torque adjustment on individual teeth. However, caution is advised as excessive initial stress may concentrate in the cervical and apical regions of the periodontal ligament and tooth.

An updated method for identifying the formative factors in soil structure

AbstractSoil structure is a standard component of pedon descriptions collected to characterize the nature and function of soils as a natural body. Soil structure is an important indicator of soil development and a predictor of water, air, and root movement throughout the profile. However, inconsistencies exist within the current standardized methodologies used to describe soil structure in the field, making soil structure data difficult to use and often confusing to students encountering these concepts for the first time. Therefore, we propose an updated method of soil structure description to add an interpretive component that clearly distinguishes geogenic, pedogenic, and human‐induced structures. This method employs terminology that communicates both observable morphology and the mechanism of formation. The updated method herein differentiates three classes of structure: (a) geogenic structural formation (GS), (b) natural pedological structural formation (current nomenclature), and (c) significant human‐induced structure changes from natural pedological structure. This updated approach improves the documentation of scientifically relevant soil morphology and communicates the processes involved in the formation of all forms of soil structure. As a result, this change eases description challenges around soil structure and interpretations common in soil science classes, including soil judging.

Phosphate promotes Arabidopsis root skewing and circumnutation through reorganisation of the microtubule cytoskeleton.

Phosphate (Pi) plays a key role in plant growth and development. Hence, plants display a range of adaptations to acquire it, including changes in root system architecture (RSA). Whether Pi triggers directional root growth is unknown. We investigated whether Arabidopsis roots sense Pi and grow towards it, that is whether they exhibit phosphotropism. While roots did exhibit a clear Pi-specific directional growth response, it was, however, always to the left, independent of the direction of the Pi gradient. We discovered that increasing concentrations of KH2PO4, trigger a dose-dependent skewing response, in both primary and lateral roots. This phenomenon is Pi-specific - other nutrients do not trigger this - and involves the reorganisation of the microtubule cytoskeleton in epidermal cells of the root elongation zone. Higher Pi levels promote left-handed cell file rotation that results in right-handed, clockwise, root growth and leftward skewing as a result of the helical movement of roots (circumnutation). Our results shed new light on the role of Pi in root growth, and may provide novel insights for crop breeding to optimise RSA and P-use efficiency.

Comparison of Upper Central Incisor Torque in the ClinCheck® with and without CBCT Integration: A Cross-Sectional Study.

Controlling root movement is one of the greatest challenges in orthodontic treatment with aligners, like Invisalign® aligners. Cone Beam Computed Tomography (CBCT) integration into ClinCheck®, enabling bone and root visualisation, allows a more accurate follow-up of the teeth position. This study aims to compare torque measurements of the upper central incisors with and without CBCT and relate them to the upper incisor inclination and facial biotype. In a sample of 70 teeth, torque measurements were obtained by importing images into AutoCAD® software (version 2024). The angle between the tooth's long axis with CBCT duplicate and the tooth's long axis without CBCT was obtained to assess the difference. Statistically significant differences between torque measurements with and without CBCT were found, as well as between these measurements and the inclination of the upper incisors. No statistically significant differences were found among the facial biotypes. The average values of 27.8° ± 3.4° and 21.5° ± 3.2° were obtained for the angle between the axes. Torque without CBCT was lower than torque with CBCT, for the same tooth. The angle between the axes had a similar mean for both teeth. CBCT integration into ClinCheck® allows for a more correct torque measurement.

How accurate is predicted root movement achieved in four first-premolar extraction cases with Invisalign?

This study aims to compare the achieved and predicted root movements in adults after four first-premolar extractions and Invisalign treatment. Thirty-three consecutive adults (22 Class I, 9 Cusp-to-cusp Class II and 2 Cusp-to-cusp Class III) from a single clinical division who completed the first series of aligners after premolar extractions were included in this retrospective study. A pretreatment cone-beam computed tomography model was registered onto the pretreatment surface-scanned dental model (SSDM) to locate the pretreatment root apices of the whole dentition. These were copied and transferred to the predicted and achieved post-treatment SSDMs to acquire the locations of the predicted and achieved post-treatment root apices. The differences between predicted and achieved root movements (DPARMs) were tested using the paired t-test or Wilcoxon signed rank test. In the anteroposterior direction, posterior root movements of maxillary and mandibular anterior teeth were poorly achieved (3.24-5.74 mm DPARMs, p < .05). In the vertical direction, roots of maxillary anterior teeth achieved greater intrusion (0.70-0.93 mm DPARMs, p < .05), while those of mandibular incisors achieved less intrusion (0.57-0.65 mm DPARMs, p < .05) than predicted. In the mediolateral direction, lateral incisor roots did not move distally (-0.65 to -0.96 mm DPARMs, p < .05), while those of canines did not move buccally, compared with the prediction (-0.75 mm DPARMs, p < .05). In the four first-premolar extraction treatments with Invisalign, root movements were not achieved as predicted, particularly for anterior teeth in the anteroposterior direction.

A comparative study of a two-stage surgical approach combining coronectomy with microimplant anchorage traction for extraction of impacted mandibular third molars with different traction angles

Objective: To establish a two-stage surgical procedure of impacted mandibular third molars (IMTMs) extractions assisted by coronectomy and microimplant anchorage traction and to investigate the influencing factors of root movement and the effects of different traction angles on the clinical outcomes. Methods: Fifty-three IMTM in contact with inferior alveolar nerve (IAN) that underwent tooth extraction in the Peking University School of Stomatology from January 2022 to June 2023 were included, with coronectomy and microimplant anchorage implantation in the first stage of the surgery, root traction was achieved with orthodontic elastic and microimplant anchorages by about 600 g of force, when the IMTM root was detached from IAN, a second surgery was performed to extract the residual root. The basic information of patients and M3M, data on the microimplant anchorage implantation and traction, imaging measurements, and complications were recorded and analyzed. Results: The movement distance of the residual roots was (1.80±0.92) mm, and the duration of traction was (32.9±7.9) d. Multiple linear regression analysis showed that the residual root movement distance was significantly correlated with age, gender, number of roots, traction angle, and depth of the distal bone defect of the second molar (P<0.05). The smaller the traction angle, the more significant the movement of the residual roots (P=0.044). In one case (1.9%, 1/53), the patient experienced abnormal sensation in the lower lip 16 days after traction. Conclusions: The two-stage surgical method of combined coronectomy with rapid traction technique to extract the IMTM allows for rapid movement of the residual root and reduces the risk of IAN injury. The efficiency of root movement can be accelerated by appropriately reducing the traction angle during surgery. The traction effect can be predicted based on indicators such as age, gender, number of roots and depth of distal bone defects of second molar.

Impact of contact rotation on the vacuum arc root movement

Impact of contact rotation on the vacuum arc root movement

The Risks Behind Fixed Retainers After Orthodontic Treatment.

Bonded fixed retainers are frequently used nowadays as the main and often the only retention protocol after orthodontic treatment. The expectations for long-lasting lifetime stability of the occlusion led orthodontists to seek the ultimate retention protocol with minimal patient compliance. Fixed retainers have many disadvantages and risks that should be considered in advance. Different failures of fixed retainers are described and categorized. The workflow for the retreatment of relapse caused in spite of the fixed retainers is described with 3 case presentations: Open bite, Root movement and Bimaxillary protrusion, all treated with clear aligner treatment (CAT). A revised retention protocol is suggested.

Biomechanical effects of clear aligner with different shape design at extraction space area during anterior teeth retraction.

This study aimed to investigate the biomechanical effects of clear aligner (CA) with different shape designs at extraction space (CAES) area during space closing. A finite-element method (FEM) model of mandibular dentition, periodontal ligaments, attachments, and corresponding CA was established. The connecting rod design of CAES was modelled for the control group. Eight test groups with different heights of CAES from -4 mm to +4 mm were designed. Tooth displacement tendencies were calculated. The maximum principal stress in PDLs, teeth, and CAs was analysed. Both global coordinate system and local coordinate system were also used to evaluate individual tooth movements. Across all groups, stresses concentrated on the lingual outer surface of CAESs. For the lowered CAES groups, both the stress value and the stress distribution area at CAESs were increased. The lowered CAES groups showed reduced movement in anterior teeth and less tipping tendency of the canines. The shape of CAES has a biomechanical impact on anterior teeth movement and should be considered in aligner design. The results suggest that increasing the height of CAES can enhance anterior teeth retraction, while lowered CAES may facilitate controlled root movement. Changes in the shape of CAES represent a potential direction for biomechanical improvement of clear aligner in extraction cases and are worth exploring.

Evaluating the Injection of Platelet-Rich Plasma on Second Lower Molars Protraction: A Randomized Controlled Clinical Trial.

Background The use of platelet-rich plasma (PRP) in dentistry was entered several decades ago, yet its clinical use in orthodontics still requires further investigation. The aim of this study was to evaluate the possible effects of local injection of PRP on the rate and typeof mandibular second molar protractionmovement compared with the comparator (no PRP) group. Material and methods Eighteen patients aged between 17 and 25 years were randomly allocated in a split-mouth study design to receive PRP injections on one sideimmediately before the start of molar protraction (PRP group), while the other side received only saline solution (comparator group). Eligibility criteria included bilaterally extracted mandibular first molars casesand indicated mandibular second molars protraction. The primary outcome of the study consisted of measuring the rate of molar protraction from the beginning of protraction (T0) to the end of the seventh month (TF), using a digital gauge. The secondary outcome included measuring the typeof second molar protraction movement between T0 and TFby lateral cephalometric images. Randomization of the intervention side was performed by picking out opaque sealed envelopes. The blinding of the principal investigator was impossible but blinding of the patient was achieved by injection of saline. Analyses were done using paired samples T-test to compare the changes in all variables between T0 and TF. The level of significance was taken at a P-value < 0.05. Results No significant difference was detected between the PRP and comparator groups in the rate of second lower molar protraction during seven months (0.56±0.07 mm per month in the comparator group, whereas, was 0.6±0.11 mm per month in the PRP group). Molar protraction parameters in both groups showed second lower molars moving by controlled tipping closer to bodily movement (Root Movement:Crown Movement≈0.8). Conclusions Platelet-rich plasma (PRP) is ineffective in accelerating the rate of orthodontic tooth movement (OTM) during molar protraction, and it has no effect on the type of tooth movement. In addition, the mechanics that we used (6 mm power arm in combination with miniscrews) are effective in mandibular second molar protraction by controlled tipping closer to bodily movement.

A system for the study of roots 3D kinematics in hydroponic culture: a study on the oscillatory features of root tip

BackgroundThe root of a plant is a fundamental organ for the multisensory perception of the environment. Investigating root growth dynamics as a mean of their interaction with the environment is of key importance for improving knowledge in plant behaviour, plant biology and agriculture. To date, it is difficult to study roots movements from a dynamic perspective given that available technologies for root imaging focus mostly on static characterizations, lacking temporal and three-dimensional (3D) spatial information. This paper describes a new system based on time-lapse for the 3D reconstruction and analysis of roots growing in hydroponics.ResultsThe system is based on infrared stereo-cameras acquiring time-lapse images of the roots for 3D reconstruction. The acquisition protocol guarantees the root growth in complete dark while the upper part of the plant grows in normal light conditions. The system extracts the 3D trajectory of the root tip and a set of descriptive features in both the temporal and frequency domains. The system has been used on Zea mays L. (B73) during the first week of growth and shows good inter-reliability between operators with an Intra Class Correlation Coefficient (ICC) > 0.9 for all features extracted. It also showed measurement accuracy with a median difference of < 1 mm between computed and manually measured root length.ConclusionsThe system and the protocol presented in this study enable accurate 3D analysis of primary root growth in hydroponics. It can serve as a valuable tool for analysing real-time root responses to environmental stimuli thus improving knowledge on the processes contributing to roots physiological and phenotypic plasticity.

Hybrid Orthodontics for Aesthetic Deep Bite Correction—Case Series and General Clinical Considerations

Background: A range of psychosocial and aesthetic factors motivate patients to undergo orthodontic treatment. The appliance choice depends not only on the type of malocclusion, but also on the aesthetic and functional demands of the patients themselves. Nowadays, digital planning enables the manufacture of individualised and customised orthodontic appliances. However, the predictability of movements with aligner treatment has long been under discussion. This article illustrates, through a series of case reports, how a hybrid approach combining individualised aesthetic orthodontic appliances can improve the predictability of tooth movements, thereby providing additional tools for clinicians charged with choosing the best indicated and biomechanically advantageous technique. To this end, three patients with different malocclusions were treated via a hybrid approach involving clear aligners in the upper arch followed by lingual fixed appliances in the upper and lower arches. All patients were treated using ALIAS lingual PSL 0.018 × 0.018-inch slot brackets and in-house 3D-printed aligners. Findings: The hybrid approach combining aligners and fixed lingual appliances led to the successful resolution of all three complex cases in the series without prolonging treatment time. The superimpositions demonstrate the predictability of even traditionally difficult movements. In particular, the Alias PSL lingual system, used from the beginning, enabled good control of both the torque and inclination of the lower incisors. Conclusions: Combining clear aligners and fixed lingual appliances provides a highly efficient means of treating malocclusions aesthetically. In our cases, the aligners offset the lack of bite-plate effect from the lingual brackets and appliances, providing advantageous biomechanics for rotation correction and control of tip, torque and root movements. Understanding how to exploit the strengths of each appliance enables the clinician to treat adult patients efficaciously, efficiently and aesthetically.

Biomechanical effect of dual-dimensional archwire on controlled movement of anterior teeth compared with rectangular archwire: A finite element study

This study aimed to determine and compare the effectiveness of the use of the dual-dimensional archwire and conventional rectangular archwire on tooth movement patterns when combined with various lengths of power arms. Displacements of the maxillary central incisor and the deformation of the wire section were calculated when applying retraction forces from different lengths of power arms using the finite element method. Torque control of the incisor could be carried out more effectively when using the dual-dimensional archwire combined with long power arms than with the rectangular archwire. The use of the dual-dimensional archwire produced bodily movement of the central incisor at height levels of the power arm between 8 and 10 mm and lingual root tipping at the level of 10 mm. The use of the dual-dimensional archwire provided better-controlled movement of the incisor, including bodily movement or root movement, than the rectangular archwire.

Effect of dynamic neuromuscular stabilization training using the inertial load of water on functional movement and postural sway in middle-aged women: a randomized controlled trial

BackgroundChronic stress and diseases occur more frequently in middle-aged compared to younger women and this is often the result of physical, psychological and socio-economic changes. These health consequences reduce lower body muscle mass and flexibility, leading to generalized impairments in functional movement and balance. Dynamic Neuromuscular Stabilization (DNS) training using the inertial load of water is known for its positive impact on functional strength improvement and muscle stabilization.ObjectiveThis study aimed to determine the effect of DNS training using inertial water loads on functional movement and postural sway in middle-aged women.MethodA sample of 24 middle-aged women participated in the study and were randomly divided into two groups: the experimental group, n = 12 (age: 58.33 ± 1.48 yrs, height: 162.16 ± 1.27 cm, weight: 61.77 ± 2.21 kg) and control group, n = 12 (age: 59.58 ± 1.13 yrs, height: 160.1 ± 1.13 cm, weight: 57.51 ± 1.12 kg). Center of Pressure (COP), moving distance, Root Mean Square (RMS), movement area and Functional Movement Screen (FMS) were conducted and analyzed pre- and post-examination. Participants engaged in the DNS training regimen, which utilized the inertial load of water, for 60 min each session, conducted twice weekly for 12 weeks.ResultsThere were significant differences in the COP distance (p < 0.001), RMS (p < 0.05), COP area and FMS test (p < 0.001) in the pre-post comparison of each group. And significant differences were found in COP distance (p < 0.05), RMS (p < 0.05), COP area (p < 0.05) and FMS test (p < 0.05) between groups. The DNS training improved the dynamic stability of single-leg standing, torso stability and functional movement in middle-aged women.ConclusionDNS training programs using the inertial load of water have been shown to be effective in movement improvement and posture retention ability, which is beneficial for functional movement, equilibrium strategy, and dynamic stability of middle-aged women. Furthermore, the DNS training method designed in this study can be useful for trainees who require posture correction in a safe and effective way regardless of their age and gender.

Christene wat Joodse gebruike opneem: Die Hebrew Roots-leerstellings, beoordeel vanuit Handelinge 10:9-29, Handelinge 15:1-35 en Galasiërs 2 en pentekostalistiese hermeneutiek

Christians taking up Jewish Customs: The Hebrew Roots doctrines evaluated from Acts 10:9–29, Acts 15:1-35, Galatians 2, and Pentecostalist hermeneutics. Numerous Pentecostal and Christian adherents are encountering Hebrew Roots teachings, with a significant global presence, notably in the USA, Israel, Europe, South America, and South Africa. In 2012, the South had a substantial number of adherents. A prominent ministry, 119 ministries, offers an interactive map listing Hebrew Roots ministries worldwide. In South Africa, over 120 such ministries are listed, primarily in Gauteng and the Western Cape. Hebrew Roots proponents claim authenticity by reverting to Jewish and Mosaic roots, advocating adherence to Old Testament precepts, including rituals and customs. This article critically assesses these claims, focusing on key texts such as Acts 10:9-29, Acts 15:1-35, and Galatians 2, in the context of the Mosaic-Hebrew roots movement. This movement argues that non-Jewish Christians should observe the Mosaic laws integral to God’s covenant with Israel. Employing a comparative literature analysis and grammatical-historical exegesis, the study contrasts Pentecostal beliefs with those of the Hebrew Roots movement concerning non-Jewish Christians’ ethical responsibilities regarding the Mosaic laws. The article first outlines the historical evolution of the Hebrew Roots movement, emphasizing its theological foundations. Subsequent sections systematically analyse the scriptural passages, examining their influence on these movements’ doctrines through a Pentecostal hermeneutical lens. One central concern highlighted is the potential for Hebrew Roots teachings to challenge the exclusive role of Christ in salvation by emphasizing adherence to the Old Testament’s legal framework, raising questions about Christ’s divinity.Intradisciplinary/intradisciplinary implications: This research seeks to prompt a critical examination within the field of Dogmatics, specifically with regard to the precise delineation of a Christian’s obligations concerning the Mosaic Law, particularly in the context of the Decalogue.

Motion behavior of a high-current fault electric arc occurred in the dead zone of protection in a substation

Since the dead-zone fault in substations often has a relatively long removal time, it may damage the insulation of power equipment and even threaten the stability of the power system. In this paper, the movement of the dead-zone fault electric arc in a 220-kV substation is investigated. The arc chain model for the dead-zone fault electric arc is developed; the influences of electromagnetic force, thermal buoyancy, and the air resistance stressed on the electric arc are comprehensively considered. The electric arc velocity and displacement are computed. Then, the spreading characteristics of the dead-zone electric arc under various conditions are studied. The spreading trend of the dead-zone fault electric arc is summarized. Finally, measures to inhibit the spreading of the electric arc are suggested. The study indicates that the movement of the electric arc in the dead zone during the early stage is primarily influenced by the electromagnetic force resulting from the overpass and conductor, and the arc is concave and has an irregular trajectory. The inclination angle of the conductor significantly affects the direction of the electromagnetic force. If the conductor is laid horizontally, the electric arc is subjected to a smaller force. The electromagnetic force stressed on the electric arc is mainly attributed to the fault phase conductor and the electric arc body itself, whereas those from the other phase conductors are minor. The initial position of the arc root has a certain impact on the movement of the electric arc. The use of the insulating materials restricts the arc root movement.

Orchid fruit and root movement analyzed using 2D photographs and a bioinformatics pipeline for processing sequential 3D scans.

Most studies of the movement of orchid fruits and roots during plant development have focused on morphological observations; however, further genetic analysis is required to understand the molecular mechanisms underlying this phenomenon. A precise tool is required to observe these movements and harvest tissue at the correct position and time for transcriptomics research. We utilized three-dimensional (3D) micro-computed tomography (CT) scans to capture the movement of fast-growing Erycina pusilla roots, and built an integrated bioinformatics pipeline to process 3D images into 3D time-lapse videos. To record the movement of slowly developing E. pusilla and Phalaenopsis equestris fruits, two-dimensional (2D) photographs were used. The E. pusilla roots twisted and resupinated multiple times from early development. The first period occurred in the early developmental stage (77-84 days after germination [DAG]) and the subsequent period occurred later in development (140-154 DAG). While E. pusilla fruits twisted 45° from 56-63 days after pollination (DAP), the fruits of P. equestris only began to resupinate a week before dehiscence (133 DAP) and ended a week after dehiscence (161 DAP). Our methods revealed that each orchid root and fruit had an independent direction and degree of torsion from the initial to the final position. Our innovative approaches produced detailed spatial and temporal information on the resupination of roots and fruits during orchid development.