Changes In Inclination Research Articles

A randomized controlled trial comparing retainers in bimaxillary proclination cases.

There is currently no recommendation for retaining corrected bimaxillary proclination cases. This study aimed to compare retention protocols for maintaining stability of such cases. In this single-center, single-blinded parallel control trial, 27 participants were assigned to three groups using block randomization with a 1:1:1 allocation ratio; fixed bonded retention (FBR), vacuum-formed retention (VFR), and dual retention (DR) comprising both types. Data were collected every 3-months from debond (T0) for 12 months (T4). The primary outcomes measured changes in soft and dental tissue parameters on traced lateral cephalograms. Secondary outcomes included intra-arch changes and the oral health impact profile (OHIP-14[M]). This trial was registered with Clinicaltrial.gov (NCT04578704). At T4, the upper lip, lower lip, and upper incisors moved anteriorly (mean difference (MD) of 1.63mm (SD 3.7), 0.48mm (SD 1.1), and 0.54mm (SD 0.97), respectively). The upper and lower incisors were proclined by 0.96 degrees (SD 2.1) and 1.11 degrees (SD 2.63), respectively. The interincisal angle was reduced by 0.56 degrees (SD 1.23). Only the upper incisor inclination (UII) change showed significant differences between groups (η² = 0.296; p = 0.015). Post-hoc comparisons revealed that the FBR and VFR groups exhibited greater proclination than the DR group (UII, MD = 3.33 degrees and 3.22 degrees, respectively). No differences were observed in OHIP-14[M] scores between the groups. All three retention protocols showed statistically small but clinically insignificant changes. Dual retention offers better control in preventing upper incisor proclination in bimaxillary proclination cases. This trial was registered with Clinicaltrial.gov (NCT04578704).

Rural Solid Waste Management: Experiences from Bihar

The pace of solid waste generation in rural areas of India has been indiscriminately increasing with the change in lifestyle and inclination towards consumer-oriented societies. The lack of solid waste management in rural areas drastically affects the overall health of the communities and ecology. The article highlights the management perspective of waste management, the impacts of community engagement and the process to be followed to plan, execute and sustain solid waste management projects for sustainable outcomes. The article is an outcome of field-based experiences from an action research project piloted in rural areas of Bihar. It was evident that various tools of community engagement, consultation with stakeholders, establishing feedback mechanisms, quality of services and motivation of sanitation workers are the building blocks of successful waste management projects.

Evaluation of angular and positional changes of maxillary third molars following premolar extraction, molar distalization, and non-extraction treatments

BackgroundTo compare the effects of first premolar extraction, molar distalization, and non-extraction treatments on the angulation and vertical positions of maxillary second molars (MxM2s) and maxillary third molars (MxM3s). To our knowledge, this is the first study to compare the effects of three different treatment types on MxM3 simultaneously.MethodsInitial (T0) and final (T1) panoramic radiographs of three different patient groups were analyzed: first premolar extraction group (n = 26 patients, 52 MxM2, 52 MxM3), molar distalization group (n = 20 patients, 40 MxM2, 40 MxM3), and non-extraction group (n = 31 patients, 62 MxM2, 62 MxM3). Descriptive data, including growth pattern, crowding, overjet, overbite, and maxillary incisor inclination, were recorded. Angular changes of maxillary third molars (MxM3) relative to the Interorbital Plane (IOP) and Palatal Plane (PP), as well as changes in inclination and vertical position according to Archer’s classification, were also documented. Differences between T0 and T1 within the same group were assessed using the paired sample t-test and Wilcoxon signed-rank test. Comparisons between groups were evaluated with one-way analysis of variance (ANOVA) and Kruskal-Wallis H test. The threshold for statistical significance was set at p < .05.ResultsIOP and PP values of MxM2 and MxM3 showed significant improvement in the extraction group (EG)(p < .001). The improvement in MxM3 IOP and PP values was not significant in the distalization group (DG)(p = .196 and p = .544, respectively). According to Archer’s classification, within-group comparisons revealed that the inclination and vertical position of MxM3 showed significant improvement in the EG, DG, and non-extraction groups (NEG)(inclination: p < .001 in EG, p = .032 in DG, p = .024 in NEG; vertical position: p < .001 in EG, p = .048 in DG, p < .001 in NEG). In between-group comparisons, the most significant improvement was observed in the EG. The number of MxM3 with vertical positions in Stages 1 and 2 at T1 were 19 in EG, 3 in DG, and 10 in NEG.ConclusionPremolar extraction has a positive effect on the angular and positional changes of MxM2 and MxM3. The changes in the inclination and vertical position of MxM3 between NEG and DG were not statistically significant.

Effect of customized 3D-printed MARPE appliance on hard tissues, soft tissues, and airway: A prospective CBCT study.

The advances in technology have enabled the customization of appliances including mini-screw-assisted rapid palatal expansion (MARPE) appliances for skeletal expansion in young adult patients. The study assessed the short-term effects of customized MARPE appliances on the hard tissues, soft tissues, and airway volume over a period of 6 months. A total of 15 patients in the age range of 15 to 25 years were treated for transverse maxillary deficiency using a three-dimensional (3D) printed customized MARPE appliance. The changes in hard tissues, soft tissues, and airway volume were evaluated using cone beam computed tomography before expansion (T0) and at 6 months post-expansion (T1). The Digital Imaging and Communications in Medicine files were analyzed for post-expansion changes using the NemoCeph 3D and 3D Slicer 5.6.1 software. An effective skeletal expansion was observed with significant changes in intercanine, interpremolar, and intermolar width; and decreased mid-palatal suture density in the anterior region (P < .05). The changes in tooth inclination and alveolar bone thickness were mostly non-significant apart from a significant decrease in buccal bone thickness in the coronal third region (P < .05). There was no significant root resorption or change in airway volumes (P > .05). The philtrum height increased significantly by 1.17 mm (P = .019) with no significant change on right and left sides. Rapid palatal expansion with 3D-printed customized MARPE enables effective and symmetrical expansion with a significant increase in philtrum height and no significant adverse effects in terms of alveolar bone thickness, dental inclination, root resorption, and airway volumes.

Dentoalveolar alterations after interventions to relieve mouth breathing : Systematic review and meta-analysis.

Mouth breathing is related to morphological and functional alterations in growing individuals. Understanding early events that can lead to these changes can prevent or decrease the need for orthodontic treatment. The goal was to assess the prognosis for dental alterations evidenced by changes in the incisor inclination and arch width after surgical intervention to normalize the mode of breathing in growing patients. Databases were searched based on the guidelines of the Preferred Report Items for Systematic Reviews and Meta-Analysis (PRISMA statement), with no restrictions on language or year of publication. Seven non-randomized studies were selected, with follow-up times ranging from 12to 60months. Differences in the inclination of the upper and lower incisors, intercanine and intermolar maxillary widths between the initial and final measurements were the primary and second outcomes. Two independent authors extracted the data independently. The Quality in Prognosis Studies tool (QUIPS tool) and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) were used to assess the risk of bias and the quality of evidence. Although four studies presented asimilar methodology and significant results regarding incisor inclination, the meta-analysis did not provide statistical evidence favoring surgical interventions for these variables (p = 0.12). No significant changes in the transverse dimension of the maxillary arch were found in the primary dentition (95% confidence interval [CI], 0.231 [-0.394/0.857], p = 0.4690). Four separate studies provided acceptable but low evidence that interventions to relieve mouth breathing in growing individuals favor normalization of lower incisor inclination. In the primary dentition, no significant changes were found in the arch width.

Aesthetic Management of Coronal Dilacerations with Enamel Hypoplasia of Permanent Maxillary Central Incisors:

Dilaceration is a peculiar developmental dental anomaly. It is associated with traumatic events of deciduous teeth affecting the permanent tooth buds. It is chiefly a precipitous change in the axial inclination between the crown and the root of a tooth. Dilacerated crown, a rare clinical presentation, is a result of the non-axial displacement of pre-formed hard tissues of a developing crown at an angle to its longitudinal axis. It conspicuously impacts the appearance of patient. Enamel hypoplasia is primarily due to the trauma or infection of primary predecessor tooth resulting in a quantitative defect in enamel of permanent successors. Occasionally, both conditions; dilacerated crown and enamel hypoplasia can occur concomitantly producing many unpropitious outcomes. This particular case is about a 14-year-old boy presenting to the Department of Operative dentistry and Endodontics for the esthetic management of anomalous maxillary central incisors. These anomalous teeth were conservatively managed using direct composite veneers.

The OsMAPK6-OsWRKY72 module positively regulates rice leaf angle through brassinosteroid signals.

Leaf angle is a major agronomic trait that determines plant architecture, which directly affects rice planting density, photosynthetic efficiency, and yield. The plant phytohormones brassinosteroids (BRs) and the MAPK signaling cascade are known to play crucial roles in regulating the leaf angle, but the underlying molecular mechanisms are not fully understood. Here, we report a rice WRKY family transcription factor gene, OsWRKY72, which positively regulates leaf angle by affecting lamina joint development and BR signaling. Phenotypic analysis showed that oswrky72 mutants had smaller leaf angles and exhibited insensitive to exogenous brassinosteroid, while the OsWRKY72 overexpression lines led to enlarged leaf angles and were hypersensitive to exogenous BR. Histological sections indicated that the change in leaf inclination was due to asymmetric cell proliferation and growth at the lamina joint. Further investigation showed that OsWRKY72 directly bound to the promoter regions of BR receptor kinase (OsBRI1), a key gene in the BR signaling pathway, and activated its expression to positively regulates rice BR signaling. In addition, we discovered that OsWRKY72 can interact with OsMAPK6 and be phosphorylated, and this phosphorylation event enhanced OsWRKY72 activity in promoting OsBRI1 expression. The genetic evidence confirmed that OsMAPK6, OsWRKY72 and OsBRI1 functions in a common pathway to regulate leaf angles. Collectively, our findings elucidate the critical role of the transcription factor OsWRKY72 in regulating rice leaf angle. These results provided valuable insights into the molecular regulatory networks governing plant architecture in rice.

Three-dimensional interpretation of geophysical and geotechnical investigation of landslides

Effective engineering design of structures requires a thorough understanding of the groundwater conditions of the substrate. In some situations, a three-dimensional survey is necessary. Landslides are examples of such cases. They are complex phenomena, and the main factors significantly influencing their behaviour over time are changes in slope geometry, inclination and water conditions. The article discusses the reconnaissance of the substrate structure in an area threatened by mass movements along a modernized section of a railway line. The analysed area is located in the marginal zone of the North Polish glacial moraine. The geological structure of the substrate consists of: glacial tills, glaciofluvial sands, lacustrine clays, and organic soils found in periodically waterlogged areas and depressions in the terrain. Colluvial deposits, mainly consisting of clayey formations, occur on the slope of the escarpment. Surface geomorphology was interpreted using LIDAR data and field observations. Two-dimensional and three-dimensional electrical resistivity tomography (ERT) was used to obtain a detailed subsurface image, which was verified by borehole drilling and laboratory analysis of soil samples for physical properties, including grain size distribution and plasticity, as well as mechanical properties of soils. This research enabled the creation of a three-dimensional substrate model, showing the spatial distribution of colluvium and areas at risk of active landslides. The results indicate that an integrated approach, combining geophysical imaging and geotechnical reconnaissance, allows for a detailed understanding of the structure and lithology of landslide areas.

Paleomagnetic inclinations and relative paleointensity variations during the upper Aptian to middle Albian in Sergipe-Alagoas Basin, South Atlantic Ocean (NE Brazil)

Summary During the Jurassic and Early Cretaceous, Earth's magnetic field experienced a high frequency of polarity reversals. This hyperactivity period is followed by a ∼38 Myr prolonged period of stable normal polarity from the Aptian until the Santonian, known as the Cretaceous Normal Superchron (CNS; chron C34n, from 121.4 to 83.65 Ma). However, the CNS might have been characterized by more variability than previously thought, but the current databaseis uneven in its spatial and temporal distribution. In this study, we integrate paleomagnetic and biostratigraphic data from the SER-03 sedimentary core, drilled onshore in the Sergipe-Alagoas Basin, NE Brazilian margin, South Atlantic Ocean. The 183-meter cored interval spans 5.2 Myr (114.7–109.5 Ma), including the Aptian–Albian transition. It records the evolution from restricted marine settings to the complete opening of the South Atlantic Ocean. Magnetic remanence and rock magnetic parameters, such as magnetic susceptibility, anhysteretic remanent magnetization, and isothermal remanent magnetization, were measured. Rock magnetic analyses indicated that primary magnetizations were preserved throughout the interval, with detrital magnetite identified as the primary magnetic carrier, predominantly in the pseudo-single domain and low-coercivity states. Normalizations by χ, ARM15mT, and IRM15mT were used to determine relative paleointensity curves and were compared to the curve resulting from the pseudo-Thellier method. The SER-03 relative paleointensity record shows marked changes in both intensity and inclination. Inclination instability results are comparable with those found in volcanic rocks from surrounding the region. The high-resolution SER-03 magnetic record revealed that the field variability was higher than expected during the CNS, but remaining substantially lower than during other periods, such as thelate Jurassic. The new SER-03can serve as a dating and correlation tool for coeval records.

Modeling of Creep Closure of Salt Rocks Drilled by Directional Wells

This paper presents a strategy for three-dimensional modelling of directional wells penetrating salt rocks, aiming at predicting the closure of these rocks due to creep. One of the major challenges in oil production in the pre-salt region is drilling through thick layers of salt rocks. During drilling, these rocks deform in the direction of the wellbore closure due to creep. The accumulated deformation of the wellbore wall over a given time interval can lead to the restriction of the drilling string's passage and even its irretrievably trapped. Directional wells in salt regions present an even greater complexity, as changes in inclination alter the stress distribution around the well, changing the configuration of the deviatoric stress, with no symmetry around the well's central axis (as in vertical wells). This paper discusses a strategy for modelling directional wells in salt regions using the commercial software Abaqus. This software implements the Finite Element Method, including its three-dimensional formulation, and allows modeling of creep deformation of materials, enabling the implementation of constitutive models different from traditional ones through subroutines. The adopted constitutive equation is the most recurrent in the literature to describe the creep phenomenon in wells through Brazilian salt rock. To verify the developed strategy, a vertical well is modelled, and the obtained results are compared with those presented by axisymmetric modeling, already consolidated in other works developed by the group. After verification, directional wells are modelled and studied, and their behavior is discussed regarding the observed displacement and stress fields, mainly along the region near the wellbore wall. This work contributes to the understanding of the creep behavior in salt rocks when drilled by directional wells, and discusses some strategies that can contribute to the stability of the rock formation, aiming at the safe and efficient construction of wells in salt regions.

Mandibular Advancement Devices in OSA Patients: Impact on Occlusal Dynamics and Tooth Alignment Modifications-A Pilot Prospective and Retrospective Study.

Background: The widespread prevalence of obstructive sleep apnea (OSA) underscores the necessity for effective therapies. Mandibular advancement devices (MADs) have emerged as valid treatment for mild to moderate cases, despite the associated dental side effects. Methods: This study evaluates the nature, onset, and long-term manifestation of these side effects. In the prospective group (n = 12), dental impressions were taken pre-MAD-insertion and at intervals of three, six, nine, and twelve months post-insertion to monitor occlusal alterations. In the retrospective group, participants (n = 8) wearing MADs for 7 years at average underwent lateral cephalogram assessments to compare with pre-treatment X-rays. All participants completed a specific questionnaire. Statistical analysis was performed via t-test and with p < 0.05 as the significance level. Results: The majority of participants in both groups consistently used MADs and reported significant sleep quality improvements, rating common symptoms like jaw tension as negligible. In both the prospective group and the retrospective group, significant reductions in overjet were observed at multiple time points, with the prospective group showing reductions at six months (p = 0.001), nine months (p > 0.001), and twelve months (p = 0.019), while the retrospective group indicated a notable decrease between baseline and follow-up assessments after a mean of seven years of device wear (p = 0.004). A slight overbite increase of 0.2 mm was prospectively observed after one year, whereas a trend towards a minimal decrease over the long term was observed in the retrospective sample (p = 0.003). Noteworthy changes in angle class or lower incisor inclination were absent. Cephalograms revealed significant IOK-NL angle alterations with a mean of 98.2° before and 95.2° upon long-term treatment (p = 0.020). Conclusions: These findings suggest that MADs are effective in treating OSA with minor adverse effects. This study advocates for moderate mandibular protrusion to balance therapeutic efficacy with dental health considerations, crucial for optimizing treatment outcomes. Nonetheless, the limited sample size warrants caution when generalizing these results to the broader population.

Assessment of Transitional Orbits from a High Eccentricity LEO to a Circumlunar Orbit

This study presents an evaluation of the achievability and execution of transitional orbits for spacecraft transitioning from a high eccentricity Low Earth Orbit (LEO) to a circumlunar orbit, with the point of distinguishing the foremost proficient and ideal trajectory while considering variables such as velocity and required fuel. Transitional orbits have a role in space exploration, and optimizing their characteristics can enormously advantage mission planning and spacecraft design. A numerical simulation model was developed to attain this objective, A gravity perturbations effect is included in the calculation of the transition. The model utilized progressed numerical integration strategies for exact trajectory analysis. Three cases were examined to investigate the impacts of varying eccentricity and the argument of perigee on the ideal transition, In the first case, eccentricity values of [0.001, 0.01, 0.1] were inspected, whereas the argument of perigee was fixed at 80 degrees. Within the second case, the argument of perigee values of [80, 170, 260] was considered, with the eccentricity fixed at 0.1. The third case included at the same time varying the eccentricity and argument of perigee values. The results showed that the three cases agreed the most favorable transition occurred when eccentricity was set to 0.001 and the argument of perigee was set to 260 degrees. This produced a velocity increase of 2.195694 km/s, which is the lowest increase in ΔV, a metric used to measure fuel efficiency and power required. This finding also demonstrated the lowest change in eccentricity, the lowest change in inclination, and the lowest change in the ascending node, all of which are indicative of increased orbit stability.

Study on the Identification Method of Planar Geological Structures in Coal Mines Using Ground-Penetrating Radar

The underground detection environment in coal mines is complex, with numerous interference sources. Traditional ground-penetrating radar (GPR) methods suffer from limited detection range, high noise levels, and weak deep signals, making it extremely difficult to accurately identify geological structures without stable feature feedback. During research, it was found that the detection energy of the same target significantly changes with the antenna direction. Based on this phenomenon, this paper proposes a geological radar advanced detection method using spatial scanning. This method overcomes constraints imposed by the underground coal mine environment on detection equipment, enhancing both detection range and accuracy compared to traditional approaches. Experiments using this method revealed pea-shaped response characteristics of planar geological structures in radar images, and the mechanisms behind their formation were analyzed. Additionally, this paper studied the changes in response characteristics under changes in target inclination, providing a basis for understanding the spatial distribution of geological structures. Finally, application experiments in underground coal mine environments explored the practical potential of this method. Results indicate that, compared to drilling data, this method achieves identification accuracies of 91.88%, 90.42%, and 78.72% for the depth and spatial extent of geological structures, providing effective technical support for coal mining operations.

Accuracy of Cup Placement Angle, Leg Lengthening, and Offset Measurement Using an AR-Based Portable Navigation System: Validation in Supine and Lateral Decubitus Positions for Total Hip Arthroplasty

Background and Objectives: Total hip arthroplasty (THA) requires accurate implant placement to ensure optimal outcomes. In this study, the AR Hip navigation system, an imageless portable navigation tool using augmented reality (AR), was evaluated for measuring radiographic inclination (RI), anteversion (RA), leg lengthening (LL), and offset (OS) changes in supine and lateral decubitus THA. Notably, this is the first report to assess the accuracy of LL and OS measurements using AR technology. Methods: We analyzed 48 hips from primary THA patients: 17 in the supine (S) group and 31 in the lateral (L) group. RI, RA, LL, and OS were measured intraoperatively using AR Hip and postoperatively using Zed Hip 3D software (Version 18.0.0.0). The absolute errors and outlier rates (≥5° for RI/RA and ≥5 mm for LL/OS) were compared between groups. Results: The mean intraoperative RI values with AR Hip were 40.1 ± 0.6° (S), 40.2 ± 1.2° (L), and 40.1 ± 1.0° (total), while the postoperative RI values with Zed Hip were 39.7 ± 2.9° (S), 39.5 ± 2.5° (L), and 39.6 ± 2.6° (total). The absolute errors were 1.8 ± 1.7° (total), with no significant group differences (p = 0.957). For RA, the errors were 2.0 ± 1.2° (total) (p = 0.771). The LL errors were 2.3 ± 2.2 mm (total) (p = 0.271), and the OS errors were 3.5 ± 2.8 mm (total) (p = 0.620). The outlier rates for RI were 11.8% (S) and 3.2% (L); for RA, 0% (S) and 3.2% (L); for LL, 29.4% (S) and 6.5% (L) with a significant difference (p = 0.031); and for OS, 23.5% (S) and 25.8% (L). No significant differences were observed for RI, RA, or OS. Conclusions: AR Hip provided accurate measurements of cup orientation, LL, and OS in both supine and lateral THA. Importantly, this study is the first to report the accuracy of LL and OS measurements using AR technology, demonstrating the potential of AR Hip for improving THA precision.

Evaluation of the Changes in the Alveolar Bone and Root Length after Maxillary Anterior Tooth Retraction and the Factors Influencing Them.

There is a scarcity of studies in which both alveolar bone remodeling and root resorption are simultaneously assessed and compared against possible influencing factors such as rate of retraction and change in inclination. The aim of our study was to assess the changes in the alveolar bone thickness and root length of the maxillary anterior teeth after retraction and correlate it to the potential influencing factors, namely rate of retraction and change in inclination. Ten patients requiring upper premolar extraction as part of their treatment were included in the study. Alveolar bone and root length changes were measured using cone beam computed tomography and the rate of retraction and change in inclination were assessed using lateral cephalograms. Two readings: Preretraction and postretraction were taken. Statistical analysis was done using Paired rank t-test and Spearman's rank correlation tests. Significance level was set at P < 0.05. The labial alveolar bone thickness showed an increase, whereas the palatal and total alveolar bone thickness showed a decrease. Root resorption was observed in all teeth. Alveolar bone changes showed a positive correlation to the rate of retraction and a negative correlation to the change in inclination. The root length change showed a positive correlation to the change in inclination.

Lip and incisor changes in patients with different ethnicities treated with extraction versus nonextraction: A cone-beam computed tomography study

This study used cone-beam computed tomography (CBCT) via voxel-based superimposition to evaluate lip and incisor changes after orthodontic treatment with four premolar extractions (Ext) versus nonextraction (Non-Ext) among African American (AA) and White (W) patients. A total of 240 CBCTs of 120 adolescent orthodontic patients with Class I skeletal/dental relationships were included. Patients were initially divided according to treatment, and then each group was subdivided according to patients' ethnicity (Ext/W = 30, Ext/AA = 30, Non-Ext/W = 30, and Non-Ext/AA = 30). CBCTs were imported into Invivo6 for voxel-based superimposition. Lip and incisor measurements were recorded. Independent t tests and two-way ANOVA were used for statistical assessment. The Non-Ext/W group had a greater increase in all outcome variables compared with the Non-Ext/AA group, with a significant change in volume and position of upper (UL) and lower lips (LL), inclination of upper (U1) and lower incisors (L1), and position of U1. The Ext/AA group had a greater decrease in all measured outcomes compared with the Ext/W group, with significant change in inclination of U1 and L1, and position and volume of LL. W patients had more crowding than AA patients in both treatment approaches. Retraction ratios of 6.5:1 and 2.1:1 were recorded between the U1 and UL positions, and L1 and LL positions, respectively. There were no direct interaction effects between ethnicity and treatment, nor were there any significant effects of ethnicity after controlling for the covariates. Ethnicity alone has no impact on incisor and lip position after treatment. However, ethnicity in the form of initial presentation of malocclusion can have a significant influence.

Is occlusal contact re-established within 6 months after bonding of a fixed anterior bite plane in adolescents with a Class II division 2 incisor relationship? A randomised controlled trial.

To determine if re-establishment of occlusal contact was achieved within 6 months after insertion of a fixed anterior bite plane in individuals with Class II division 2 incisor relationship, and to evaluate the occlusal and vertical skeletal changes and acceptance of the intra-oral scanner and bite plane. Single-centre two-arm parallel group randomised controlled trial with 1:1 allocation to intervention and control groups. Dundee Dental Hospital and Research School, UK. A total of 38 participants aged 9-16 years (11 males, 27 females) with Class II division 2 incisor relationship and increased overbite (greater than one-third incisor overlap). Participants were randomised to intervention (n = 19) and control (n = 19) groups using block randomisation. The intervention group had a fixed anterior bite plane, and the occlusion and vertical facial dimensions were monitored with intra-oral scans, lateral cephalograms and photographs. The control group received no treatment and occlusal and vertical facial dimensions were monitored with scans and photographs. Questionnaires were completed by participants and parents/carers. An intention-to-treat analysis was planned. The overbite reduced in all participants in the intervention group (mean initial overbite: 5.07 mm, 95% confidence interval [CI] = 4.15-6.00; mean overbite after 6 months: 2.45 mm, 95% CI = 1.93-2.96). There was a mean incisor intrusion of 0.29 mm (95% CI = 0.17-0.42) and mean eruption of the first molars of 0.23 mm (95% CI = 0.09-0.37). There was no significant change in incisor inclination or vertical skeletal change. Feedback from participants and their parents/carers were generally positive. Fixed anterior bite planes effectively reduce an increased overbite in adolescents with a Class II division 2 incisor relationship, due to a combination of incisor intrusion and molar eruption with no change in incisor inclination or vertical skeletal change. Intra-oral scanning and fixed anterior bite planes are acceptable in adolescents.

STEAM INDUCED SHOCKWAVE INTERACTION WITH A SUBMERGED PLATE CONFIGURED AT A RANGE OF INCLINATIONS FROM VERTICAL

Interaction of shock wave and the shear induced vortex across the steam-water layer has been vital in several transportation and chemical industrial processes. Experiments were conducted using a facility including a rectangular chamber, which housed a shock tube in it. Steam was injected into the tube to induce shock wave by bursting the Aluminum diaphragm disk and the shock wave surrounding by the steam-water shear layer induced vortex, exited the shock tube and struck the rectangular steel plate. PIV setup along with the pressure and acoustic emissions sensors were used to characterize the propagation and impingement of the shock wave on the plate as well as the behavior of the reflected shock wave and the vortex ring. In case of a vertical rectangular steel sheet stationed in front of the exit of the shock tube, the central part of the shock wave was found to interact with the central part of the vortex structure and the external part of the shock wave came into contact with the outer part of the vortex structure. Whereas in case of inclined sheet, the shockwave reflected from the sheet, came into collision with the rebound shockwave as well as with the lower portion of the vortex ring largely. However, with the further variation in the angle of inclination (i.e. 30o and larger) fromvertical axis, no further appreciable change was observed in the flow profile except the vortex ring interacted earlier with the rebounded shockwave in the lower region within the neighborhood of the plate than the interaction of the vortex ring with the rebounded shock wave in the upper region of the inclined plate. The pressure and acoustic emission measurements were symmetric with the vertical plate, however, the pressure data was asymmetric when the plate was inclined from vertical. When the angle of inclination changes to 30 degrees from the vertical, the flow becomes more asymmetric as the shockwave and the consequent vortices impinged on the surface of the plate much earlier than the 15 degrees’ inclination case.

Changes in mandibular width and frontal-lower facial profile after orthognathic surgery using sagittal split ramus osteotomy with removal of internal bone interference in patients with class III skeletal malocclusion

BackgroundThe purpose of this study is to analyze changes in mandibular width and frontal view ramus inclination using cone beam CT in patients with skeletal class III malocclusion who underwent BSSRO, with the removal of bone interference between segments. MethodsFor all 20 subjects, cone-beam CT imaging was performed prior to surgery (T1), immediately post-surgery (T2), and 6 months after surgery (T3). Reorientation was performed using R2GATE software (MegaGen, Seoul, Korea). The gonion and antegonial notch were used as reference points in the sagittal view, and the most lateral point of the condyle head was used as the reference point in the frontal view. All measurements were recorded in the frontal view.ResultsInter-gonial width decreased by 2.64 mm at T3-T2 (P < .001) and by 2.58 mm at T3-T1 (P < .05). Inter-antegonial width decreased by 1.75 mm at T3-T2 (P < .05) and by 3.5 mm at T3-T1 (P < .001). In the frontal view, the right ramus inclination based on the gonion increased by 2.07° at T3-T1 (P < .05). The left ramus inclination based on gonion increased by 2.45° at T2-T1 (P < .05) and by 3.94° at T3-T1 (P < .001). The right ramus inclination based on antegonial notch increased by 2.35° at T2-T1 (P < .05) and by 3.04° at T3-T1 (P < .01). The left ramus inclination based on antegonial notch increased by 2.73° at T2-T1 (P < .001) and by 3.18° at T3-T1 (P < .001).ConclusionsDuring bilateral sagittal split osteotomy, removing bone interference between the proximal and distal segments results in a reduction of postoperative mandibular width and an increase in frontal view ramus inclination.

Long-term outcomes of acetabular impaction grafting with cemented cups and trabecular metal for revision hip arthroplasty: a follow-up study.

Revision hip arthroplasty in the presence of complex acetabular deficiencies is challenging. Cement, allograft, reconstruction rings and porous trabecular metal now provide versatile options for acetabular fixation and restoration of acetabular offset. We compare acetabular impaction bone grafting (AIBG) and trabecular metal (TM) cups at long-term follow-up. 53 patients who underwent revision hip arthroplasty were retrospectively reviewed from local joint registry data. 36 patients were revised using AIBG and 17 with TM. Median clinical follow-up was 9.57 (2.46-18.72) years and 9.65 (7.22-12.46) years, respectively. 82% of the TM group and 63% of the AIBG group were ⩾ Paprosky 2C. Re-revision was considered failure. Radiographs demonstrating 5 mm of femoral head migration and 5° of acetabular component inclination change were considered loose. Patients receiving AIBG were younger (68 vs. 74 years) with a longer interval from initial arthroplasty to revision (17 vs. 13 years). Revisions in both groups were indicated most commonly for failed cementing (AIBG 88.9% vs. TM 70.5%). No TM reconstructions underwent re-revision, with only 1 failing at 6.3 years, compared with 9 AIBG re-revisions. When revising for sepsis, 33% of AIBG revisions failed. AIBG demonstrated high failure rates at long-term follow-up when compared to TM constructs. We recommend the use of AIBG in small cavitary defects only. We strongly advise against its use in the setting of significant bony defects and for prosthetic joint infection.