Botulinum toxin augmented surgery versus conventional surgery in the management of large-angle concomitant esotropia: A randomized clinical trial.

BACKGROUND: The surgical management of large-angle concomitant esotropia is challenging with high reoperation rates. This study aims to assess the effectiveness and safety of intraoperative botulinum toxin A (BTA) augmentation compared to surgery alone in large angle concomitant esotropia. MATERIALS AND METHODS: This is a prospective randomized interventional study. Patients with large angle concomitant esotropia (≥55 prism diopter [PD]) were randomly allocated to either surgery only (Group I) or BTA augmented surgery (Group II). The surgical effect in PD/mm was calculated and compared between the study groups at all follow up intervals. Treatment was considered successful if the patients had orthotropia ± 10 PD at their final examinations. RESULTS: A total of 23 patients were included in the study, 11 in Group I and 12 in group II. The surgical effect was significantly greater in Group II compared to Group I at all follow up durations. The 1-year surgical effect was 32.5% greater in Group II compared to Group I (5.99 ± 0.69 vs. 4.52 ± 0.91 PD/mm, respectively, P = 0.001). The success rate was greater for Group II compared to Group I (75% vs. 63.64%, respectively), but this difference was not statistically significant (P = 0.901). CONCLUSION: Botulinum toxin augmented surgery is a good alternative to surgery alone in the treatment of large angle concomitant esotropia. BTA injection exerts a significant augmentation effect on medial rectus muscle recessions.

Performance evaluation of two different software programs for automated ASPECTS scoring in patients with suspected stroke.

BACKGROUND: The range of software available to radiologists has increased enormously with the advancement of AI. A good example of this is software to determine ASPECTS in the treatment of potential stroke patients. OBJECTIVE: In this study, two software packages (eASPECTS from Brainomix and VIA_ASPECTS from Siemens) were tested and compared for their performance in the daily clinical routine of a maximum care provider with a 24/7 stroke unit. METHODS: A total of 637 noncontrast CT images were obtained from consecutive patients with suspected stroke, of whom 73 were finally diagnosed with MCA infarction. Differences in agreement and quantification of agreement were analysed, as well as the correlation and sensitivity, specificity and accuracy compared to raters. RESULTS: Compared to VIA_ASPECTS, eASPECTS shows good agreement and strong correlation with the raters. VIA_ASPECTS has lower accuracy and low specificity than eASPECTS but a higher sensitivity. CONCLUSION: Both software products have the potential to be decision support tools for radiologists. There are, however, differences between the two software products in terms of their intended use.

Transversus abdominis plane block versus caudal block with bupivacaine and dexmedetomidine for unilateral inguinal hernia repair in pediatric patients: a randomized clinical trial.

BACKGROUND: This study compared the transversus abdominis plane (TAP) block with bupivacaine and dexmedetomidine to the same mixture in the caudal block in delivering postoperative analgesia in children after unilateral inguinal hernia surgery. METHODS: The current study included 80 children aged two to eight years who were scheduled for unilateral inguinal hernia surgery under general anesthesia. A caudal block (1 mL/kg 0.25% bupivacaine and one µg /kg dexmedetomidine) or a TAP block (1 mL/kg 0.25% bupivacaine and one µg /kg dexmedetomidine) was given to each participant at random. The time it took to request analgesia for the first time, the postoperative pain score, total analgesic use, sedation, family satisfaction, and side effects were all measured. The primary outcome was time to first analgesic request. RESULTS: The caudal block group had a considerably shorter time to first analgesic request than the TAP block group. The caudal block group received more rescue analgesia doses within 24 hours than the TAP block group. The mean total dose of intravenous paracetamol within the first 24 hours postoperatively was greater in the caudal block group. The caudal block group had much higher family satisfaction. CONCLUSIONS: The TAP block and caudal block provide good postoperative analgesia in children undergoing unilateral inguinal hernia repair. Adding dexmedetomidine to the TAP block was superior to the caudal block in terms of extending the length of the initial analgesic request, lowering analgesic requirement, and lowering pain scores without causing substantial adverse effects.

Conversion of archeological iron rust employing coconut husk lignin.

Rust powder collected from an archeological iron was evaluated by complementary analyses such as FTIR, XRD, XRF, and SEM/EDX. The analyses revealed that lepidocrocite (L) was the major component in the archeological iron. Coconut husk (CH) can be classified as a type of lignocellulosic biomass of renewable resources that are widely available, especially in coastal areas. In this research, the isolated lignin extracted from CH is being studied as a potential alternative for environmentally friendly applications. The isolated lignin from soda and organosolv pulping went through several analyses such as FTIR, NMR (13C and 2D-HSQC), and TGA analyses. The analyses showed that lignin isolated via soda pulping has superior antioxidant capabilities due to its greater phenolic-OH content compared to lignin isolated from organosolv pulping. The effects of lignin concentrations, pH, and reaction time were utilized in rust conversion studies of an archeological iron. 5 wt% of soda lignin (SL) was revealed as the ideal condition in this rust conversion study with a value of 84.21 %. The treated rust powder with 5 wt% of SL was then further gone through several complementary analyses, which revealed that the treated rust had nearly transformed into an amorphous state.

A case report of pedal monkeypox in a HIV patient: A challenging diagnosis with a misleading history.

Pedal Monkeypox is a disease which can mimic many other pedal conditions. It should always be considered in differential diagnosis. A young male HIV patient who presented with a tender foot lesion and diagnosed with pedal Monkeypox as a result of performed tests is discussed hereby in the case report. We expect that this case report adds to the existing literature on this subject.

Assessment of macular microvascular changes in children following treatment of anisometropic myopic amblyopia using optical coherence tomography angiography.

PURPOSE: To evaluate macular microvascular changes in the form of foveal avascular zone (FAZ) area and vessel density in the superficial, deep capillary plexuses, and choriocapillaris using optical coherence tomography angiography (OCTA) in children with anisometropic myopic amblyopia before and after treatment. METHODS: This prospective observational study included 32 patients younger than 12 years old with anisomyopic amblyopia. OCTA was done before patients' treatment with optical correction with or without patching and was repeated after successful amblyopia treatment. Outcomes included superficial, deep, and choriocapillaris vessel density (VD) and superficial and deep FAZ areas. RESULTS: The study included 13 males (40.6%) and 19 females (59.4%), and the mean age was 9.52 ± 1.33 years. Fifty-three percent (53%) of patients needed only optical correction, and the remaining 47% needed additional patching therapy. After successful treatment, there was a significant improvement in amblyopic eyes in best-corrected visual acuity (p < 0.001), with higher VD values in superficial capillary plexuses (p < 0.001), deep capillary plexuses (p < 0.001), and foveal choriocapillaris (p = 0.030). In the glasses with patching subgroup, the difference between pre-treatment and post-treatment parameters revealed a significant improvement in vessel density in superficial retinal plexuses (foveal and parafoveal; p values 0.023 and < 0.001, respectively) and deep retinal plexuses (whole image, foveal, and parafoveal; p values 0.003, < 0.001, and 0.002, respectively). While amblyopic eyes treated with glasses alone had a significantly greater difference in choriocapillaris foveal VD (p value = 0.022). CONCLUSION: After effective amblyopia treatment, amblyopic eyes exhibited improved best-corrected visual acuity and better macular perfusion along the superficial, deep vascular density, and choriocapillaris foveal VD. CLINICAL TRIAL REGISTRATION: CinicalTrials.gov Identifier: NCT05223153.

Measuring the sustainability of neighborhoods: A systematic literature review.

Neighborhoods have received worldwide interest in sustainability assessment due to their suitable scale for representing the relationship between the individual and the city. Consequently, this has led to a focus on developing neighborhood sustainability assessment (NSA) systems and, thereby, studying the prominent NSA tools. Alternatively, this study aims to uncover formative concepts shaping the assessment of sustainable neighborhoods based on a systematic review of the empirical work by researchers. The study included a Scopus database search for papers measuring neighborhood sustainability and a literature review of 64 journal articles published between 2019 and 2021. Our results suggest that criteria related to sustainable form and morphology are the most widely measured criteria in the reviewed papers, interconnected with multiple aspects of neighborhood sustainability. The paper contributes to expanding the existing knowledge on neighborhood sustainability evaluation, further adding to the literature on designing sustainable cities and communities and achieving Sustainable Development Goal 11.

A roadmap toward implementing health technology assessment in Egypt.

Background: The Egyptian healthcare system is currently in the early phase of health technology assessment (HTA) implementation. The aim of this study is to propose an implementation roadmap based on the national healthcare system status. Methods: A survey was conducted among Egyptian healthcare sector decision-makers to assess the current and future (preferred) HTA implementation status in Egypt based on a widely used international scorecard methodology. Subsequently, interviews were conducted with experts representing middle- and top-tier management in the Egyptian healthcare system to interpret the survey results and recommend specific actions. Results: Experts recommended more capacity-building programs for HTA and health economics. Additionally, they proposed establishing HTA units in separate healthcare authorities and merging them into a single central HTA unit in the long term. Regarding the scope of implementation, experts recommended commencing with the assessment of innovative pharmaceuticals, and thereafter, expanding the scope to cover all health technologies in the long term. Additionally, they recommended using innovative tools such as "multi-criteria decision analysis (MCDA)" for tendering, and "managed entry agreements" for reimbursement decisions. Local burden of diseases and costing studies were also recommended to facilitate the implementation of HTA. Conclusion: Experts agreed that several actions are required for successful HTA implementation in Egypt, including coordination between HTA bodies, application of an explicit MCDA framework, and strengthening of local evidence generation. To implement these actions, investment in technical capacity-building is indispensable. Most experts favored using multiple and soft cost-effectiveness thresholds. Efforts should be made to publish HTA submission guidelines and timelines of the processes.

Development and validation of a decision support tool for the diagnosis of acute heart failure: systematic review, meta-analysis, and modelling study.

OBJECTIVES: To evaluate the diagnostic performance of N-terminal pro-B-type natriuretic peptide (NT-proBNP) thresholds for acute heart failure and to develop and validate a decision support tool that combines NT-proBNP concentrations with clinical characteristics. DESIGN: Individual patient level data meta-analysis and modelling study. SETTING: Fourteen studies from 13 countries, including randomised controlled trials and prospective observational studies. PARTICIPANTS: Individual patient level data for 10 369 patients with suspected acute heart failure were pooled for the meta-analysis to evaluate NT-proBNP thresholds. A decision support tool (Collaboration for the Diagnosis and Evaluation of Heart Failure (CoDE-HF)) that combines NT-proBNP with clinical variables to report the probability of acute heart failure for an individual patient was developed and validated. MAIN OUTCOME MEASURE: Adjudicated diagnosis of acute heart failure. RESULTS: Overall, 43.9% (4549/10 369) of patients had an adjudicated diagnosis of acute heart failure (73.3% (2286/3119) and 29.0% (1802/6208) in those with and without previous heart failure, respectively). The negative predictive value of the guideline recommended rule-out threshold of 300 pg/mL was 94.6% (95% confidence interval 91.9% to 96.4%); despite use of age specific rule-in thresholds, the positive predictive value varied at 61.0% (55.3% to 66.4%), 73.5% (62.3% to 82.3%), and 80.2% (70.9% to 87.1%), in patients aged <50 years, 50-75 years, and >75 years, respectively. Performance varied in most subgroups, particularly patients with obesity, renal impairment, or previous heart failure. CoDE-HF was well calibrated, with excellent discrimination in patients with and without previous heart failure (area under the receiver operator curve 0.846 (0.830 to 0.862) and 0.925 (0.919 to 0.932) and Brier scores of 0.130 and 0.099, respectively). In patients without previous heart failure, the diagnostic performance was consistent across all subgroups, with 40.3% (2502/6208) identified at low probability (negative predictive value of 98.6%, 97.8% to 99.1%) and 28.0% (1737/6208) at high probability (positive predictive value of 75.0%, 65.7% to 82.5%) of having acute heart failure. CONCLUSIONS: In an international, collaborative evaluation of the diagnostic performance of NT-proBNP, guideline recommended thresholds to diagnose acute heart failure varied substantially in important patient subgroups. The CoDE-HF decision support tool incorporating NT-proBNP as a continuous measure and other clinical variables provides a more consistent, accurate, and individualised approach. STUDY REGISTRATION: PROSPERO CRD42019159407.

Biomechanical behavior of endodontically treated premolars restored with different endocrown designs: Finite element study.

PURPOSE: Although endocrown is a successful restorative approach for endodontically treated molars, its survival rate in endodontically treated premolars with extensive loss of coronal structure has been debated. The aim of this study was to evaluate the biomechanical behavior of endodontically treated maxillary premolars restored with different lithium disilicate endocrown designs. MATERIALS AND METHODS: Based on cone-beam computed tomography (CBCT) of an intact maxillary premolar, five models were designed. Model A: fiber post, core, and crown; Model B: endocrown, 5 mm pulpal extension and butt margin; Model C: endocrown, 5 mm pulpal extension and axial extension; Model D: Endocrown, 3 mm pulpal extension and butt margin; Model E: Endocrown, 3 mm pulpal extension and axial extension. The bone geometry was simplified as a cylinder of compact and trabecular bone. All models were imported into finite element analysis (FEA) software, where the base of the bone cylinder was chosen as fixed support. Axial and oblique loads of 100 N each were applied separately to each model, and static structural analysis was performed. RESULTS: Regardless of the design of the endocrown, the resulting von Mises stresses were far below the yield strength of the tooth structure and the flexural strength of the ceramic material. The generated von Mises stresses on the restoration decreased by 15% in the models with 3 mm pulp extension (D and E) compared to the 5-mm pulpal extension models. In addition, the resulting von Mises stresses on the tooth structure decreased also by 15% in models C and E with the axial extension compared to models B and D with the butt margin. CONCLUSION: Endocrown is a suitable restoration for endodontically treated maxillary premolars. Furthermore, reducing the depth of the pulpal extension to 3 mm with the addition of an axial extension resulted in a more favorable stress distribution within the tooth-restoration interface.

Does Radial Artery Cannulation Affect the Perfusion of the Dominant Hand in Adult Patients with Normal Modified Allen's Test Undergoing Cardiac Surgeries? Data Derived from the Peripheral Perfusion Index.

OBJECTIVES: This study aimed to evaluate the effect of radial artery cannulation on hand perfusion in patients with normal modified Allen's test undergoing cardiac surgeries using cardiopulmonary bypass (CPB). DESIGN: Prospective follow-up study. SETTING: Single institution, Assiut University Cardiothoracic Hospital. PARTICIPANTS: Forty-nine patients who underwent cardiac surgeries using cardiopulmonary bypass were enrolled. INTERVENTIONS: Cannulation of radial artery in the dominant hand using a 20-gauge catheter. MEASUREMENTS AND MAIN RESULTS: The primary outcomes were the mean peripheral perfusion index (PPI) >60 seconds (mean PPI60) and the thumb temperature, which were measured at different times before and during the surgery. There was a statistically significant difference in the mean PPI60 between both hands (p = 0.033). Before skin incision, the mean PPI60 was significantly higher in the noncannulated hand (p < 0.001). Also, there was a statistically significant difference in the thumb temperature between both hands (p = 0.013). At low core body temperature, the thumb temperature was significantly lower in the noncannulated hand (p = 0.017). CONCLUSIONS: In adult patients undergoing cardiac surgeries using CPB, even with normal modified Allen's test, radial artery cannulation may affect the perfusion of the dominant hand, especially at low arterial blood pressure or low core body temperature. Since the PPI is one of the noninvasive methods used for intraoperative assessment of the peripheral perfusion, the authors recommend the use of the noncannulated hand for this purpose to not misguide this assessment.

Corrigendum to "Outcome of a Low-Cost Glaucoma Implant versus the Baerveldt Glaucoma Implant for Paediatric Glaucoma in a Tertiary Hospital in Egypt".

[This corrects the article DOI: 10.1155/2019/5134190.].

Amenorrhea, premenstrual tension syndrome, and dysmenorrhea among women of reproductive age on hemodialysis: A national study in Egypt.

BACKGROUND AND AIM: The current literature concerning the reproductive health of end stage renal disease (ESRD) females is scarce, outdated, and largely unknown in women living in developing countries. This study aims to estimate the prevalence of menstrual abnormalities and their associated factors among ESRD women in reproductive age undergoing chronic hemodialysis (HD) in Egypt. METHODS: Thirty-five dialysis centers were selected by simple random sampling to represent the different regions of Egypt. Non-pregnant women in the reproductive age (15-50 years) receiving dialysis at the participating centers completed a questionnaire about their menstrual health during a routine hemodialysis session. Their responses were verified by reviewing the medical records and assessing their clinical data. RESULTS: Out of the 472 women, 32.6% had amenorrhea. Menstrual irregularities were reported in 37% of the menstruating women. Premenstrual tension syndrome (PMS) was reported in 70% while dysmenorrhea in 58%. Amenorrhea was more prevalent in non-working women who started hemodialysis after the age of 30. PMS was more encountered in women with hypertension or in those with obstructive uropathy or autoimmune disease as a cause of ESRD. Dysmenorrhea was more prevalent among patients with autoimmune disease or chronic hepatitis C virus and those who started dialysis after the age of 30. CONCLUSION: Secondary amenorrhea, dysmenorrhea, and PMS are common among premenopausal women with ESRD on dialysis. Several factors including socio-economic factors, cause of ESRD, and hypertension contribute to these disorders. Future studies are needed to understand the underlying pathophysiologic mechanisms and management of these abnormalities.

Thin-Flap Laser In Situ Keratomileusis-Associated Dry Eye: A Comparative Study Between Femtosecond Laser and Mechanical Microkeratome-Assisted Laser In Situ Keratomileusis.

OBJECTIVE: To assess and compare postlaser in situ keratomileusis (LASIK) dry eye after LASIK with planned thin flaps created by a femtosecond laser (FS) and mechanical microkeratome (MK). METHODS: Patients were stratified according to the flap creation technique into FS and MK groups with planned 100 µm flap thickness in all eyes. Dry eye parameters including tear film break-up time (TBUT), Schirmer I test, ocular surface disease index (OSDI), and lower tear meniscus height and area (tear meniscus height [TMH] and tear meniscus area [TMA]) were assessed before surgery and at 3 and 6 months after surgery. RESULTS: The study included 102 eyes of 55 patients (52 eyes underwent FS-LASIK/50 eyes underwent MK-LASIK). The preoperative characteristics including age, gender, and spherical equivalents were similar in both groups (P>0.05). The difference in postoperative flap thickness was statistically significant (P<0.05). In each group, dry eye parameters showed a statistically significant worsening (P value<0.001) at 3 months with later significant improvement at 6 months but did not return to baseline. The mean TBUT, Schirmer I, and lower TMH and TMA were statistically higher, and the mean OSDI was statistically lower in FS-LASIK than the MK-LASIK group at both 3 and 6 months (P value<0.001). The depth of ablation had a statistically significant correlation with Schirmer I at 6 months and OSDI at both 3 and 6 months post-LASIK (P<0.05). CONCLUSION: The use of femtosecond laser technology in performing thin-Flap LASIK eye surgeries has improved the outcome of post-LASIK dry eye when compared with the mechanical microkeratome.

Biomechanics in Removable Partial Dentures: A Literature Review of FEA-Based Studies.

The present study was aimed at reviewing the studies that used finite element analysis (FEA) to estimate the biomechanical stress arising in removable partial dentures (RPDs) and how to optimize it. A literature survey was conducted for the English full-text articles, which used only FEA to estimate the stress developed in RPDs from Jan 2000 to May 2021. In RPDs, the retaining and supporting structures are subjected to dynamic loads during insertion and removal of the prosthesis as well as during function. The majority of stresses in free-end saddle (FES) RPDs are concentrated in the shoulder of the clasp, the horizontal curvature of the gingival approaching clasp, and the part of the major connector next to terminal abutments. Clasps fabricated from flexible materials were beneficial to eliminate the stress in the abutment, while rigid materials were preferred for major connectors to eliminate the displacement of the prosthesis. In implant-assisted RPD, the implant receive the majority of the load, thereby reducing the stress on the abutment and reducing the displacement of the prosthesis. The amount of stress in the implant decreases with zero or minimal angulation, using long and wide implants, and when the implants are placed in the first molar area.

An in vitro / in vivo release test of risedronate drug loaded nano-bioactive glass composite scaffolds.

Three-dimensional (3D) matrices scaffolds play a noteworthy role in promoting cell generation and propagation. In this study, scaffolds prepared from chitosan/polyvinyl alcohol loaded with/without an osteoporotic drug (risedronate) and nano-bioactive glass (nBG) have been developed to promote healing of bone defects. The scaffolds were characterized by scanning electron microscopy (SEM), porosity test as well as mechanical strength. The pattern of drug release and ability to promote the proliferation of Saos-2osteosarcoma cells had also been reported. Osteogenic potential of the scaffolds was evaluated by testing their effect on healing critical-sized dog's mandibular bone defects. Increasing chitosan and nBG in the porous scaffolds induced decrease in drug release, increased the scaffold's strength and supported their cell proliferation, alkaline phosphatase (ALP) activities, as well as increased calcium deposition. Histological and histomorphometric results demonstrated newly formed bone trabeculae inside critical-sized mandibular defects when treated with scaffolds. Trabecular thickness, bone volume/tissue volume and the percentage of mature collagen fibers increased in groups treated with scaffolds loaded with 10% nBG and risedronate or loaded with 30% nBG with/without risedronate compared with those treated with non-loaded scaffolds and empty control groups. These findings confirmed the potential osteogenic activity of chitosan/polyvinyl alcohol-based scaffolds loaded with risedronate and nBG.

Preoperative gabapentin versus bisoprolol for haemodynamic and surgical field optimisation during endoscopic sinus surgery: A randomised controlled trial.

BACKGROUND AND AIMS: Appropriate premedication can optimise haemodynamics and hence surgical field visibility during endoscopic sinus surgery (ESS). This study aimed to compare the intraoperative effect of gabapentin 1200 mg versus bisoprolol 2.5 mg, given 2 hours before ESS. METHODS: Patients were assigned into one of three groups. Patients of gabapentin group received preoperative oral gabapentin 1200 mg while, patients of bisoprolol and control groups received oral bisoprolol 2.5 mg and placebo respectively 2 hours before ESS. Primary outcome: reduction of blood loss and surgical field quality. Secondary outcome: haemodynamic control. mean arterial pressure (MAP) and heart rate (HR) were recorded as baseline, before and after induction of anaesthesia, at 1, 5, 10, 15 minutes after intubation and then every 15 minutes until the end of surgery. Data also included Fromm and Boezaart category scale (assessed every 15 min), intraoperative blood loss, surgeon satisfaction score, intraoperative anaesthetic/analgesic and vasoactive medications requirements. RESULTS: Out of 66 eligible patients, 60 patients completed the study. Intraoperative MAP and HR were significantly lower and more stable in gabapentin and bisoprolol groups compared to control group (p < 0.05). The volume of blood loss was significantly lower (p 0.000) and operative field was more visible in gabapentin and bisoprolol groups than those in control group (p 0.000). CONCLUSION: The beneficial effect of gabapentin 1200 mg on intraoperative haemodynamic control and surgical field visibility is comparable to that of bisoprolol 2.5 mg when either of them is given as a single oral dose 2 hours before ESS.

Haemodynamic effects of the nitroxyl donor cimlanod (BMS-986231) in chronic heart failure: a randomized trial.

AIMS: Nitroxyl provokes vasodilatation and inotropic and lusitropic effects in animals via post-translational modification of thiols. We aimed to compare effects of the nitroxyl donor cimlanod (BMS-986231) with those of nitroglycerin (NTG) or placebo on cardiac function in patients with chronic heart failure with reduced ejection fraction (HFrEF). METHODS AND RESULTS: In a randomized, multicentre, double-blind, crossover trial, 45 patients with stable HFrEF were given a 5 h intravenous infusion of cimlanod, NTG, or placebo on separate days. Echocardiograms were done at the start and end of each infusion period and read in a core laboratory. The primary endpoint was stroke volume index derived from the left ventricular outflow tract at the end of each infusion period. Stroke volume index with placebo was 30 ± 7 mL/m2 and was lower with cimlanod (29 ± 9 mL/m2 ; P = 0.03) and NTG (28 ± 8 mL/m2 ; P = 0.02). Transmitral E-wave Doppler velocity on cimlanod or NTG was lower than on placebo and, consequently, E/e' (P = 0.006) and E/A ratio (P = 0.003) were also lower. NTG had similar effects to cimlanod on these measurements. Blood pressure reduction was similar with cimlanod and NTG and greater than with placebo. CONCLUSION: In patients with chronic HFrEF, the haemodynamic effects of cimlanod and NTG are similar. The effects of cimlanod may be explained by venodilatation and preload reduction without additional inotropic or lusitropic effects. Ongoing trials of cimlanod will further define its potential role in the treatment of heart failure.

Pediatric Stainless-Steel Crown Cementation Finite Element Study.

OBJECTIVE: To study the effect of using different cement types under pediatric stainless-steel crown (SSC) around mandibular second primary molar using three-dimensional (3D) finite element analysis. MATERIALS AND METHODS: A 3D finite element model was built for pediatric mandibular molar by laser scanning of natural extracted tooth. Four types of cement (zinc phosphate, glass ionomer, resin-modified glass ionomer, and resin) of 200 µm layers thickness were tested under a stainless-steel crown of 130-µm thickness. Twelve case studies were reported within this research, as the applied load of 330 N was tested with three angulations: vertical, oblique at 45°, and laterally. RESULTS: Linear static stress analysis was performed. The resultant stresses and deformations' distribution patterns did not change with cement type, while the values were altered. All deformations and stresses were found within the normal range. CONCLUSIONS: Analysis results indicated that using stiffer cement material increases tooth structure stresses and reduces crown body stresses and deformations, while bone was nearly insensitive to cement type.

Quantification of Macular Microvascular Changes in Retinitis Pigmentosa Using Optical Coherence Tomography Angiography.

PURPOSE: To investigate macular structural and microvascular changes in retinitis pigmentosa (RP) eyes compared to age-matched controls using spectral domain optical coherence tomography (SD-OCT) and OCT angiography (OCTA). METHODS: This was a cross-sectional study. The foveal and parafoveal thickness and extent of ellipsoid zone (EZ) disruption were measured on OCT. The foveal avascular zone (FAZ) area and retinal vessel density (VD) were automatically calculated for superficial (SCP) and deep capillary plexuses (DCP) and choriocapillaris using OCTA-integrated software. VD was assessed for the whole 6 × 6 mm image, foveal and parafoveal regions. Quantitative measures were compared between healthy and diseased eyes. RESULTS: The study included 30 eyes of 30 RP patients and 24 eyes of 24 controls. Mean age was 26.9±6.4 years for RP patients and 27.4±4.9 years for controls (p=0.76). Mean LogMAR visual acuity (VA) was 0.9±0.5 for RP patients and 0.05±0.05 for controls (p <0.001). Foveal and parafoveal thicknesses were significantly lower in RP cases as compared to the control group. EZ disruption was observed in RP cases only (869±211 µm). Mean FAZ area was significantly larger in RP eyes in both SCP and DCP. VD was significantly reduced in RP eyes at the level of SCP, DCP and choriocapillaris. VA, deep parafoveal VD, foveal, parafoveal and whole image choriocapillaris VD were negatively correlated with the extent of EZ disruption. CONCLUSION: We report OCTA findings in a relatively young cohort of RP patients. We demonstrated a reduction of retinal microvascular density in all studied layers on OCTA. We believe studying retinal vasculature in these patients is important, as a healthy blood supply is a prerequisite for the success of new cell-based therapies under trial for RP.