Vertical Deviation Research Articles

Comparison of Low-speed Drilling and Conventional Drilling in Implant Surgery: an Experimental Study.

To compare accuracy, duration of drilling and accumulation of bone chips between low-speed drilling and conventional drilling in freehand implant placement surgery. The implant surgery procedures were performed using identical drill bits on pig ribs in the low-speed drilling group and the conventional drilling group. CBCT images of the preoperative implant design and postoperative implant positions were compared by using the space vector formula to calculate the angular deviation of the implants between the two groups, as well as the horizontal and vertical deviations of the implant necks and roots. The duration of the procedure was recorded, and the bone chips were collected and compared using a screening method and scanning electron microscopy. There were no significant differences in any of the four primary outcome variables relating to accuracy between the low-speed and conventional drilling methods. However, the results revealed that the length of the procedure differed significantly between the two groups and more large bone fragments could be collected when performing low-speed drilling. Low-speed drilling does not affect the accuracy of implant nest preparation, but it can harvest large bone chips which may have better osteogenic activity. Low-speed drilling could be an alternative to conventional drilling.

Clinical pattern and burden of strabismus in a teaching institute of Northeast India

ABSTRACT Purpose: To determine the clinical pattern and burden of strabismus in a teaching institute of Northeast (NE) India. Methods: In this hospital-based, cross-sectional study, detailed clinical evaluation of patients with manifest strabismus was carried out for a period of one and half years. Results: Out of the 7222 new outpatient department attendances, a total of 110 new patients with manifest strabismus were found, with a hospital-based burden of 1.52% [95% confidence interval: 1.3–1.8]. Comitant strabismus was seen in 84.55%, and incomitant in 15.45%. Exotropia comprised 70%, esotropia 26.36%, hypertropia 10%, and hypotropia 2.72%. The angle of deviation was large in most of the participants (69.09%) with a mean of 34.90 ± 17.08 PD for horizontal and 13.29 ± 8.97 PD for vertical deviations. A cause of strabismus could be identified in 30.91%. Paralytic strabismus was seen in 15.45%, sensory in 11.82%, infantile in 1.82%, and accommodative in 1.82%. Amblyopia was found in 5.45%. In our study, 25.45% patients underwent strabismus surgery, while 74.55% patients either needed conservative management or were being worked up for surgery till the end of this study. Conclusion: This study determined the pattern and burden of strabismus in a teaching institute of NE India. Since the institute caters to patients from different states of NE India, this study gives an indirect picture of the burden of strabismus of the whole of NE India. It is hoped that these data will aid in determining the overall burden of strabismus in the country. They will also help the family medicine and primary care physicians to have an idea about the burden and pattern of strabismus in the community, thus enabling them to create awareness about strabismus, remove the undue apprehensions of patients, and do timely referrals for treatment and prevent irreversible visual loss.

The Frequency of Occurrence of Strabismus in Infants Post Lensectomy.

Purpose To identify and characterize incident cases of strabismus and interocular visual acuity among infants post lensectomy for congenital cataract. Method This was a single-centre retrospective chart review of all children aged less than 12 months who underwent lensectomy from 1st January 2014 to 1st January 2021. Cases were identified from theatre coding and electronic medical records. Cases with strabismus prior to cataract surgery were excluded. Results Seventy-five children (114 aphakic eyes) were included, 36 (48%) had unilateral cataract surgery while 39 (52%) had bilateral. The mean age at the time of cataract surgery was 3.0±2.5 months (range 1 - 10 months). The mean follow-up period was 41.2±22.8 months (range 2 -72 months). Nineteen out of 75 patients (25%) developed strabismus, most of whom (18 cases) had unilateral surgery. Out of the 19 strabismus cases recorded, esotropia was reported in 74% of the cases, followed by exotropia -16%, while esotropia associated with dissociated vertical deviation (DVD) and esotropia associated with inferior oblique each made up 5% of the population. Most children who developed strabismus [17 patients (89.5%)] had lensectomy prior to 6 months of age. A significant difference of 0.65 logMAR was recorded in the interocular visual acuity (IOVA) difference between the strabismic and non-strabismic groups, and the unilateral and bilateral lensectomy groups. Conclusion Strabismus, most commonly esotropia, is common after congenital lensectomy, particularly in those children who underwent unilateral cataract surgery, and in those less than 6 months of age.Monitoring IOVA and strabismus incidence post-cataract surgery is crucial for early intervention and amblyopia prevention.

Application of 3D-printed resin guides for the removal of molar fiber posts

To evaluate the digital guide technique for removing fiber posts from molars and compare it with the conventional microscope-assisted ultrasound method. Two mandibular dentition models, each comprising six extracted molars, were prepared. Two thick and straight canals distributed separately in the distal and mesial roots of each molar were selected for placing the fiber posts. The 24 posts in the two dentition models were removed using 3D-printed resin guides, or a microscope and an ultrasonic device. The time taken to remove the fiber post from each tooth was recorded. The volume loss, deviation values (angular deviation and horizontal and vertical deviations of the tip), and formation of microcracks before and after fiber post removal were determined using micro-computed tomography images. The digital guide technique took significantly less time than the microscope-assisted ultrasound technique (p < 0.05). No significant differences in horizontal and vertical tip deviations were observed between the two groups. The angular deviation and volume loss in the guide group were significantly lower than those in the ultrasound group (p < 0.05). New dentin microcracks were formed in the ultrasound group but not in the digital guide group. Using a 3D-printed resin guide plate can shorten the fiber post removal time and improve the stability and safety compared to the microscope-assisted ultrasound technique. 3D-printed resin guides can reduce the fiber post removal time and provide better stability and safety than the conventional method.

An artificial intelligence platform for the screening and managing of strabismus.

Considering the escalating incidence of strabismus and its consequential jeopardy to binocular vision, there is an imperative demand for expeditious and precise screening methods. This study was to develop an artificial intelligence (AI) platform in the form of an applet that facilitates the screening and management of strabismus on any mobile device. The Visual Transformer (VIT_16_224) was developed using primary gaze photos from two datasets covering different ages. The AI model was evaluated by 5-fold cross-validation set and tested on an independent test set. The diagnostic performance of the AI model was assessed by calculating the Accuracy, Precision, Specificity, Sensitivity, F1-Score and Area Under the Curve (AUC). A total of 6194 photos with corneal light-reflection (with 2938 Exotropia, 1415 Esotropia, 739 Vertical Deviation and 1562 Orthotropy) were included. In the internal validation set, the AI model achieved an Accuracy of 0.980, Precision of 0.941, Specificity of 0.979, Sensitivity of 0.958, F1-Score of 0.951 and AUC of 0.994. In the independent test set, the AI model achieved an Accuracy of 0.967, Precision of 0.980, Specificity of 0.970, Sensitivity of 0.960, F1-Score of 0.975 and AUC of 0.993. Our study presents an advanced AI model for strabismus screening which integrates electronic archives for comprehensive patient histories. Additionally, it includes a patient-physician interaction module for streamlined communication. This innovative platform offers a complete solution for strabismus care, from screening to long-term follow-up, advancing ophthalmology through AI technology for improved patient outcomes and eye care quality.

Gas dynamic optimization of the work process of a single-stage cooled axial turbine with an inside baffle

The article presents the results of optimization of the work process of a single-stage axial turbine in order to increase its efficiency. During optimization, it was necessary to preserve the construction of the original turbine as much as possible. To solve this problem, a parameterization scheme for turbine blades and path contours was developed, taking into account the design and technological limitations. The turbine nozzle blade had an inside baffle. To control the possibility of placing the baffle, a special program was developed that automatically monitors the spatial position of the sections of the blade of the nozzle set. A post-processing program was developed to control the flow parameters at the turbine outlet in height. The efficiency and the vertical deviation of the angle of the outflow from the turbine from the original one were used as optimization criteria. The limitations were the mass flow rate of the working fluid and the total pressure ratio of the turbine. The problem was solved in several stages with different changing variables. As a result of solving the problem, it was possible to increase the turbine efficiency by 0.9%

Use of a Microelectromechanical Systems Sensor for Objective Measurements of Abnormal Head Posture in Congenital Superior Oblique Palsy Patients.

The purpose of this study was to design an objective method for measurement of head positions as achieved with use of a microelectromechanical systems (MEMS) sensor. In addition, to use this system to observe the abnormal head position (AHP) in patients with congenital superior oblique palsy (SOP) before and after their surgery. An MEMS sensor was designed for recording of the pitch, roll, and yaw values of the head position in real time. The MEMS sensor was then fixed on the synoptophore from -30 degrees to +30 degrees positions horizontally and vertically to test the accuracy of these measurements. Then, we tested 13 participants with AHP using the MEMS method and the photographic method and compared their correlations. Finally, the pitch, roll, and yaw values of head positions were measured using this MEMS sensor in 31 patients with congenital SOP as performed before and after their surgery. The MEMS sensor (LPMS-B2; Alubi, Guangzhou, China; 400 hertz [Hz]), as based on the theory of a gyroscope, was designed and connected to a smartphone via Bluetooth. It was able to conveniently record the patient's pitch, roll, and yaw head positions in real time, recordings which were consistent with the scales of the synoptophore (P > 0.05) and good correlations with the photographic method (P < 0.001). The main preoperative AHP in patients with SOP was roll (22/31, 71%). Pre- and postoperative vertical deviations were 16.4 ± 7.3 prism diopters (PD) and 4.1 ± 4.2 PD, respectively (P = 0.001). The AHP in patients with SOP was positively correlated with the angle of extorsion in the dominant eye (P = 0.01), rather than that of the vertical deviation. The MEMS sensor described in this report is a simple, practical, and accurate objective device for use in head position measurements. In patients with SOP, the AHP is related to the angle of extorsion in the dominant eye. The MEMS sensor was designed as a micro-wireless dynamic high-precision device for AHP measurement, which has the potential for use in a clinic.

Control Analysis of Building Under Construction from Indoor Mobile Mapping Systems

Abstract. During the execution phase of construction projects, quality defects arise due to various factors such as human intervention, technical aspects, logistical issues and environmental influences. Early detection of these defects is imperative to minimize their impact and prevent possible delays, increased costs and safety hazards. This paper explores the effectiveness of indoor mobile laser scanners for geometric quality control, adhering to established European technical norms and Spanish standards. Our developed approach presents a simple method for rapid assessment, capable of identifying vertical deviations in columns and walls, axis deviation in columns, flatness deviation in horizontal planes and level deviation using LIDAR data from Mobile Mapping Systems. This methodology has been validated through a real-world case study, demonstrating its practical applicability.

Examining the Influence of Freehand, Pilot-Guided, and Fully Guided Surgical Protocols on the Accuracy of Immediately Placed Implants—An In Vitro Study

This study aimed to evaluate the influence of the guidance level on the accuracy of immediately placed implants. Methods: Eighteen identical maxillary models (randomly split into three groups (n = 6): fully guided (FG), pilot-guided (PG), and freehand (FH)) were used to place 72 implants (n = 24). After placement, the mean global, angular, mesial–distal, buccal–palatal, and vertical deviation at the platform and apex of the placed implants, relative to the preoperatively planned positions, was calculated. Results: Significant differences in global and mesial–distal deviation were found between implants in the FG group and implants in the PG and FH groups. Significant differences were also found between the implants in the FG and FH groups as well as the implants in the PG and FH groups in terms of angular and mesial–distal apex deviation. Finally, significant differences were found between the implants in the FG and PG groups in terms of buccal–palatal platform deviation. Conclusions: The results of this in vitro study show that immediate implants placed using fully guided surgical guides have significantly less deviation, and are therefore more accurate, than implants placed freehand or using pilot guides, but this should be further validated in a clinical trial.

Comprehensive analysis of strabismus reoperations: clinical insights and progression factors

BackgroundTo compare and analyze clinical characteristics of patients undergoing two surgeries and multiple surgeries and explore relevant factors to lay the foundation for clinical prediction.MethodsA retrospective analysis was conducted on clinical data from all patients who underwent twice and multiple strabismus surgeries at Tianjin Eye Hospital between October 2012 and September 2021. Patients were divided into Group A (two surgeries) and Group B (more than two surgeries) based on the cumulative number of surgeries performed. Clinical details at the first recurrence, including sex, age, native place, overall medical history, onset time, visual acuity, affected muscle(s), etc., were documented. Non-parametric tests and chi-square tests were used to analyze clinical characteristics in each group. Binary and ordered logistic regression analysis assessed parameters associated with multiple reoperations. A linear mixed-term model observed factors impacting affected muscle(s) during surgery. Researchers examined clinical traits related to secondary strabismus variables.ResultsAmong the 910 included patients, 840 required two surgeries (Group A) and 70 underwent more than two surgeries (Group B). Significant differences were found in age, onset time, interval time, and secondary factors. Regression analysis highlighted the significant impact of interval time on the reoperation rate, effectively predicting outcomes in patients with concomitant strabismus. Other ophthalmoplegia and secondary factors significantly influenced reoperation rates in patients with non-concomitant strabismus. Interval time, esotropia, and exotropia were linked to concomitant secondary strabismus patients, while the number of surgeries, DVD, esotropia, exotropia, and esotropia V-pattern were associated with non-concomitant secondary strabismus patients. In a longitudinal study, patients with multiple surgeries showed a correlation between the vertical deviation angle magnitude and the number of involved extraocular muscles. Regression analysis revealed that in patients with concomitant strabismus, interval time, exotropia, and esotropia influenced the total number of muscles during surgery. For patients with non-concomitant strabismus, interval time, secondary factors, and SOP impacted the total number of muscles during surgery.ConclusionsInterval time in patients with concomitant strabismus, as well as secondary and other ophthalmoplegia in non-concomitant strabismus, are the main factors for multiple reoperations.

LARGE INFERIOR RECTUS RECESSION WITHOUT LOWER LID RETRACTION: TWO INCREDIBLE TECHNIQUES

Relevance. Lower lid retraction is a frequent undesirable result following inferior rectus recession operations. Especially in relatively larger amounts of recession, a special and close relationship between lower lid retractors and muscular fascia makes the complication more severe. Purpose of the study. To introduce two methods that allow wide inferior rectus recession without causing lower eyelid retraction and to evaluate the long-term results. Material and methods. There were 25 cases and 18 control group cases in first operation technique named ‘ninety percent of posterior fibers recession of inferior rectus’ which can be perform for any vertical deviation without muscle fibrosis; and 8 cases were in second operation technique which named ‘muscle elongation with both organic tissue and non-absorbable suture’. Results and conclusion. In both technique patients’ deviation corrected and all ocular movement was free. Both operation techniques, which introduces by us, does not affected lower lid retractor and operations has both effective results and no lid problem.

A multifunctional scannable mounting device for computer guided implant surgery: An in vitro study

As part of the growing digitization of the dental field, clinicians are looking for ways to simplify digital workflow, reduce chairside time, and provide new work patterns for future applications. Whether scanning with a multifunctional apparatus (MFA) scan body results in improved scanning is unclear. The purpose of this in vitro study was to compare the horizontal, vertical, and angular deviations with the MFA scan body with a commercially available scan body (SBIO). Sixteen identically printed edentulous maxillary models were used to plan two Ø3.8×11.5-mm implants in the right maxillary first molar and left maxillary central incisor locations. Two implants in each model were installed using a surgical guide. The models were scanned using an intraoral scanner with MFA and then rescanned twice, with SBIO using the intraoral scanner and a laboratory 3D scanner. The implants were digitally positioned according to the scanned MFA and SBIO locations in standard tessellation language (STL) files. These STL files were superimposed on the reference laboratory 3D scanner STL files. Linear measurements included implant apex/cervical horizontal/vertical deviations, as well as implant axis angular deviations. Normality was evaluated with the Shapiro-Wilk test. Paired samples t tests (2 sided) were used for the mean SBIO-MFA deviation difference. To compare the molar/incisor sites, paired samples Wilcoxon tests were used (α=.05 for all tests). No statistically significant differences were found between the MFA/ SBIO deviations, for each of the 10 sites × deviation combinations (P>.05). Overall, the lowest endpoint of the 95% confidence intervals among the 8 linear measurement comparisons was -0.107 mm (coronal vertical deviation, right maxillary first molar site) and -0.30 degrees between the 2 angular measurement comparisons. The current in vitro study demonstrated high accuracy for the novel MFA device, similar to that of the standard SBIO scan body. Furthermore, the current study offers an alternative technique to evaluate the accuracy of implant placement by using scanning and back programming over the traditional postplacement cone beam computed tomography (CBCT) scanning.

Coexistence of congenital superior rectus muscle fibrosis and Marcus Gunn jaw-winking phenomenon

A 6-year-old male involving a coexistence of congenital fibrosis of the superior rectus muscle (SR) with Marcus Gunn Jaw-Winking phenomenon presented with an elevation of the upper eyelid along with a chronically open mouth that had been present since early infancy. There was extropia and hypertropia, a limitation of elevation and depression in the right eye, and an abnormal head posture (AHP) with a left head tilt, right face turn, and a chin-up head position. He also displayed an upper eyelid retraction and a 2-mm lagophthalos in the right eye. Results of the forced duction test indicated a constricted SR of the right eye. A dissection of the SR from the levator palpebrae superioris and a 5-mm SR recession was performed within the right eye. At 2 months post surgery, there was a 3 prism diopters (PD) hypertropia in the right eye when the left eye was fixated on the target and a 10 PD hypotropia in the left eye when the right eye was fixated on the target, along with an improvement in his AHP. In this rare case with a coexistence of congenital fibrosis of the SR and Marcus Gunn jaw-winking phenomenon, we found that the performance of an individualized surgical protocol proved effective in reducing the vertical deviation and improving AHP.

DATA INVESTIGATION OF PK-LQP AIRPLANE VERTICAL DEVIATION USING CLASS 1 AND TIER 1 DATASETS

The vertical deviation is one of the important stages in commercial aircraft flights because indications of malfunction can be detected faster by the pilot rather than in other flight phases. The purpose of this study is to investigate whether the PK-LQP airplane experienced unusual altitude movements during the vertical deviation phase since the airplane taking off from Seattle (Boeing Manufacture's home base) until the airplane crash. The airplane, which is of the type B737 MAX8, had operated for 83 days, during which it completed 438 flights using a total of 107 flight codes, and it travelled to 36 airports. According to the findings of an investigation of the data, we found that only 69 (39%) were included in tier 1, which had an ADS-B data update interval message below 10 seconds, complying with ICAO and FAA-AVN standards. With this class 1 and tier 1 dataset, we conducted an EDA to find the data insight, which revealed that there was a disturbance in the speed and altitude indications on the airplane instrumentation, causing a misperception for the pilot and causing the airplane to drastically drop in altitude (more than 100 feet).

Anterior Nasal Superior Oblique Tendon Syndrome: A Case Series

PurposeTo evaluate the clinical characteristics and management of patients with an anteriorly and nasally inserted superior oblique tendon. DesignRetrospective interventional case series. MethodsInstitutional clinical records between 2020 and 2024 were retrospectively reviewed for 9 consecutive patients in whom the superior oblique (SO) tendon was inserted anterior to the equator and nasal to the superior rectus muscle. Information collected included age, sex, ocular and surgical history, preoperative and postoperative data (ophthalmologic examinations, strabismus measurements, ductions and versions), intraoperative findings, need for additional surgery, and follow-up time. ResultsAll nine patients were found to have an anomalous insertion of the SO tendon. Three were of congenital origin and six were acquired following ocular surgery. Among the acquired cases, all but one resulted from incarceration of the tendon from post-surgical scar tissue formation. The remaining acquired case was due to a prior deliberate anterior and nasal transposition of the superior oblique. This case series demonstrated varying degrees of vertical deviations, lateral incomitance, and limited depression. Repositioning the SO to its normal insertion site yielded equivocal improvement in ocular alignment. ConclusionAnterior nasal superior oblique tendon syndrome is a rare clinical entity characterized by an anti-depressor effect. Vertical deviations, hypertropia worse in downgaze, limited depression worse in adduction for congenital cases and in abduction for acquired cases, and lateral incomitance may be indicative of this anomaly. In acquired cases following surgery, additional findings may include limited depression worse in abduction, esotropia in abduction, V-pattern esotropia, and enophthalmos in downgaze. Surgical repositioning of the SO along its normal anatomical trajectory is recommended for treatment. However, outcomes may be variable and achieving a complete resolution of this syndrome can be challenging.

Automated position control of tunnel boring machine during excavation using deep reinforcement learning

Position control of tunnel boring machines (TBM) is critical to ensure precise construction and meets design specifications. However, the high dependence on human intervention largely affects the efficiency and reliability of the operations due to slow response, inconsistent judgment and high risk of errors. Targeting to automate the position control of the TBM to enable it to the planned route in a more efficient and reliable manner, this research proposes a deep reinforcement learning (DRL) method considering spatial-temporal dynamics to perform automated real-time TBM operations. The DRL algorithm is embedded with a time-series deep learning model to simulate the working environment with dynamic time-space variations. The whole process is coupled with the designed reward and evaluation metrics for model enhancement. To showcase the viability and applicability of the suggested approach, a project from Singapore is utilized as an illustrative example. The outcomes indicate that the suggested method exhibits robust capabilities in forecasting and controlling TBM positions, with an R2 of 0.86 and 0.92 in forecasting the horizontal and vertical deviations of the TBM tail three steps ahead and an overall improvement of 50.7 %. The proposed method is capable of providing an optimal strategy to intelligently forecast and control the TBM deviation. The novelty of this method comes from the feasible integration of time series prediction and DRL to simulate the spatial-temporal dynamics along with TBM excavation and obtain a position control model for optimal tunneling strategy, contributing to the effective facilitation of TBM tunneling to improve efficiency and reliability.

Anteriorization of the inferior oblique muscle versus anteriorization and resection for asymmetrical dissociated vertical deviation

ABSTRACT Purpose To compare the efficacy of two methods: first, bilateral symmetric anteriorization of the inferior oblique muscle and second: combined resection and anteriorization of the inferior oblique (IO) muscle for asymmetric dissociated vertical deviation (DVD). Design Prospective randomized clinical trial. Methods This study included fifty-four patients presenting with bilateral asymmetric DVD and inferior oblique overaction (IOOA). Two equal groups were randomly allocated by odd and even number distribution. Twenty-seven patients underwent bilateral symmetric anteriorization of the IO muscle and twenty-seven patients underwent anteriorization of the IO of one eye and anteriorization with IO resection in the eye with the larger deviation. According to the difference in measured DVD between the two eyes whether less or more than 5 PD; a 3 or 5 mm resection was done, respectively. Results The mean post-operative reduction of DVD in the anteriorization group was 9.19 ± 3.40 PD in the right eye and 8.78 ± 4.17 PD in the left eye, which were highly significant. (p-value .0002). The resection group had a mean post-operative DVD reduction of 11.7 ± 2.74 PD in resected eyes and 7.3 ± 3.72 PD in non-resected eyes. These reductions were also highly significant (p-value 0.0001). Reduction of inter-ocular difference between both groups failed to show a statistical difference (p-value 0.285). The IOOA was significantly reduced in both groups. Improvement in the average post-operative DVD between the two groups and the post-operative improvement in IOOA failed to show a statistically significant difference (p-value 0.265 and 0.804 respectively) which showed that both procedures are effective. Conclusion Both surgical modalities are effective in managing asymmetric dissociated vertical deviation associated with IOOA.

Relationship between binocular vision and Govetto’s stage in monocular idiopathic epiretinal membrane

Govetto’s staging system (stages 1–4) for epiretinal membrane (ERM) based on optical coherence tomography images is a useful predictor of monocular visual function; however, an association between Govetto’s stage and binocular vision has not been reported. This study aimed to investigate the factors associated with Govetto’s stage among the monocular and binocular parameters. This retrospective study included consecutive patients with treatment-naïve eyes with unilateral ERM without pseudo-hole. We investigated Govetto’s stage, degrees of aniseikonia and metamorphopsia, foveal avascular zone area, central retinal and choroidal thickness, vertical ocular deviation, stereopsis, and binocular single vision (BSV). We compared the parameters between the BSV-present and BSV-absent groups and investigated correlations between Govetto’s stage and the monocular and binocular parameters. Twenty-eight eyes of 28 patients were examined (age, 66.6 ± 10.2 years). In multivariate correlation analyses, Govetto’s stage correlated with BSV (P = 0.04, β = − 0.36) and central retinal thickness (P < 0.001, β = 0.74). Of the eyes, 18 were assigned to the BSV-present group and 10 to the BSV-absent group. Govetto’s stage was significantly more advanced in the BSV-absent group than in the BSV-present group (3.2 ± 0.8 vs 2.5 ± 0.7, P = 0.03). Of the 28 patients, 11 (39%) showed small-angle vertical deviations (1–12Δ). In conclusion, our findings showed that Govetto’s stage correlated with binocular vision in patients with monocular ERM. Govetto’s staging is a useful parameter for predicting not only monocular but also binocular vision.

Accuracy of Implant Placement Using Digital Prosthetically-Derived Surgical Guides: A Systematic Review

Dental implant placement is crucial in oral rehabilitation, requiring precision for successful outcomes. Digital technologies, including surgical guides, enhance predictability and efficiency in implant procedures. However, their impact on implant positioning accuracy is still under investigation. This systematic review aimed to evaluate the literature on implant accuracy using digital prosthetically-derived surgical guides. Registered in PROSPERO (CRD 42023483194), the review employed a PICO strategy and searched PubMed for English-language, in vivo studies from 2013 to 2023 on restrictive digital prosthetically-derived surgical guides. Two reviewers independently assessed records, with a third verifying the decisions. PRISMA guidelines were followed, yielding 24 results after excluding nine duplicates. Ten studies met the criteria after title, abstract, and keyword review, with three included after verification. These studies showed coronal deviations of 0.44 mm to 0.56 mm, apical deviations of 0.64 mm to 1.03 mm, angular deviations of 2.03° to 2.42°, and vertical deviations of 0.19 mm to 0.45 mm. Superior accuracy was noted with static guided techniques, while bilateral guides offered stability and printed guides were cost-effective. A surgical guide that comes from a planning with a primary wax-up of the prosthesis leads to the placement of a dental implant that can be functionally and esthetically rehabilitated. Further research is needed to standardize outcomes and improve implant protocols and patient outcomes.

Surgical treatment of unilateral acquired superior oblique muscle palsy in adults by inferior oblique belly transposition: a retrospective analysis.

Evaluate and analyze the efficacy of inferior oblique belly transposition (IOBT) in treating adult patients with diplopia and small-angle hypertropia caused by mild to moderate inferior oblique overaction (IOOA) secondary to acquired superior oblique palsy (SOP). Nine adult patients with diplopia and small-angle hypertropia associated with mild to moderate IOOA secondary to unilateral acquired SOP were included in the current retrospective study. All patients received the IOBT procedure between February 2019 and May 2023 at The Second People's Hospital of Jinan and were followed up for more than 6months after the surgery. During the procedure, the belly of the inferior oblique muscle was fixed to the sclera at 5mm posterior to the temporal insertion of the inferior rectus muscle. The following indicators were reviewed pre- and post-surgery: the vertical deviation (VD) in the primary position and in the Bielschowsky test, the fovea disc angle (FDA) of the affected eye, changes in IOOA, and diplopia. After IOBT, the VD in the primary position decreased from 7.22△ ± 1.72△ (range 4△-10△) to 1.22△ ± 1.30△ (range 0△-3△). The VD in the Bielschowsky test decreased from 13.00△ ± 1.80△ to 3.22△ ± 1.09△. The FDA decreased from 10.02° ± 3.34° to 6.26° ± 1.91°. The grade of IOOA was reduced from 2.00 (1.00, 2.00) to 0.00 (0.00, 1.00). All changes were statistically significant (P < 0.001 or P = 0.006). Diplopia was resolved completely for all patients. IOBT can effectively treat adults with diplopia and small-angle hypertropia caused by mild to moderate IOOA secondary to acquired SOP.