Photogrammetry technology in implant dentistry: A systematic review.

STATEMENT OF PROBLEM: Photogrammetry technology may be useful in implant dentistry, but a systematic review is lacking and is indicated before routine use in clinical practice. PURPOSE: The purpose of this systematic review was to assess the role of the photogrammetry technology used in implant dentistry and determine its validity as an accurate tool with clinical applications. MATERIAL AND METHODS: Four major databases, PubMed MEDLINE, Google Scholar, Scopus, and Web of Science, were selected to retrieve articles published from January 2011 to February 2021 based on custom criteria. The search was augmented by a manual search. After screening of the collected articles, data, including study design and setting, type of application, digitizer used, reference body, method of evaluation, and overall outcomes, were extracted. RESULTS: Twenty articles were included based on the selection criteria. Most of the articles confirmed that the use of photogrammetry was promising as an implant coordinate transfer system. However, few articles showed its use for 3-dimensional scanning, which might require more development. CONCLUSIONS: The initial reports of using photogrammetry technology considered this method as a valid and reliable clinical tool in implant dentistry. More studies to develop the photogrammetry technology and to assess the results with evidence-based research are recommended to enhance its application in different clinical situations.

Ultrasound-guided quadratus lumborum block in pediatrics: trans-muscular versus intra-muscular approach.

PURPOSE: Quadratus lumborum (QL) block has four approaches. However, there is difference between the four approaches regarding efficacy, safety and adverse effects. The primary objective of this study is to compare the analgesic effect between trans-muscular and intra-muscular approaches of the QL block in pediatric patients for elective lower abdominal surgery. METHODS: 54 patients aged between 1 and 6 years were enrolled. Patients of both genders were selected. The patients were randomly classified into two groups: Group TQL includes patients (27 patients) in whom bilateral QL block was performed using trans-muscular approach, and Group IQL (27 patients), which underwent bilateral QL block using an intra-muscular approach. The primary outcome measure was the number of patients who require rescue analgesia in the first 24 h. The secondary outcome measures were FLACC score, heart rate, non-invasive blood pressure at 2, 4, 6, 12, and 24 h postoperatively, and postoperative complications (e.g., quadriceps muscle weakness, local hematoma). RESULTS: In the first 24 h after surgery, 13 patients in the IQL group (48.1%) required rescue analgesia, whereas only five patients in the TQL group (18.5%) required rescue analgesia. The FLACC score was lower in the TQL group than the IQL group at all time intervals up to 24 h postoperatively. In the TQL group, eight patients (29.6%) developed quadriceps weakness; whereas, only one patient (3.7%) in the IQL group developed quadriceps weakness. CONCLUSION: TQL is better than IQL in the analgesic efficacy following the pediatric lower laparotomy.

Longitudinal analysis of head and somatic growth in fetuses with congenital heart defects.

PURPOSE: Fetal head and somatic growth dynamics differs in fetuses with congenital heart defects (CHD). We longitudinally characterized fetal head and somatic growth in relation to the type of CHD. METHODS: Four hundred eleven exams from isolated CHD were compared with 1,219 controls. Head and somatic growth was assessed using head circumference (HC), brain volume (BrV = 1/6 × π × (HC/π)3)/2), fetal cephalization index (FCI = BrV/[estimated fetal weight]), and growth percentile. Umbilical and middle cerebral artery Doppler indices were obtained. CHD were grouped as: (1) d-transposition of great arteries (n = 11); (2) left ventricular outflow tract obstruction with retrograde isthmic flow (n = 18); (3) left ventricular outflow tract obstruction with antegrade isthmic flow (n = 16); (4) pulmonary outflow tract obstructions (n = 22). RESULTS: The smallest head size was seen in group 1. Growth asymmetry was diagnosed in group 2. Brain sparing was seen in groups 2 and 4 (p < 0.0001). HC and BrV percentiles decreased with advancing gestational age (p < 0.001) in group 2, and a significant drop was observed around 28 weeks. CONCLUSIONS: d-Transposition of great arteries and left-sided CHD leading to isthmic blood flow reversal are associated with delayed head growth. Prenatal evaluation of central hemodynamics in CHD may be contributive for predicting neurodevelopmental risks in CHD and help directing prenatal interventions. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:96-104, 2017.

Design and synthesis of some substituted thiazolo[3,2-a]pyrimidine derivatives of potential biological activities.

In continuation to our previous work, thiazolopyrimidines 2a-x were synthesized through intramolecular cyclization of 2-phenacylthio-dihydropyrimidine hydrobromides 1a-x using polyphosphoric acid. On the other hand, thiazolo[3,2-a]pyrimidine-3-one 3 was coupled with aryldiazonium salts or condensed with isatin to afford compounds 4a-c or 5, respectively. Chemical structure of the target compounds was substantiated by IR, FT-IR, (1)H-, (13)C and DEPT-(13)C NMR, MS as well as microanalyses. Moreover, the lipophilicity of the target compounds is expressed as Clog P. The antimicrobial screening of the test compounds 2a-x, 4a-c and 5 revealed moderate activity in comparison to reference drugs. Compounds 2a-c, 2e, 2o and 2v showed a gradual increase in their anti-inflammatory activity reaching its maximum at 5 h compared to indomethacin. Furthermore, the analgesic activity of compounds 2a-c, 2e, 2o and 2v revealed a maximum activity after 5 h of injection compared to aspirin and the LD50 of compounds 2e and 2v was determined.

Molecular modeling studies and synthesis of novel methyl 2-(2-(4-oxo-3-aryl-3,4-dihydroquinazolin-2-ylthio)acetamido)alkanoates with potential anti-cancer activity as inhibitors for methionine synthase.

Cobalamin-dependant cytosolic enzyme methionine synthase (MetS) catalyses the transfer of a methyl group from the methyltetrahydrofolate (MTHF) to homocysteine (Hcy) to produce methionine and tetrahydrofolate (THF). MetS is over-expressed in the cytosol of certain breast and prostate tumour cells. Methionine used as a source of one carbon atom for the building of the DNA of the tumour cells, structural protein and enzymes. In this study, we designed, synthesized and evaluated the cytotoxic activity of a series of substituted methyl 2-(2-(4-oxo-3-aryl-3,4-dihydroquinazolin-2-ylthio)acetamido)acetate and dipeptide that mimic the substructure of MTHF. These inhibitors were docked in to the MTHF binding domain in such the same way as MTHF in its binding domain. The free energies of the binding were calculated and compared to the IC50 values. This series has been developed by dicyclohexylcarbodiimide (DCC) and azide coupling methods of amino acid esters with carboxylic acid derivatives, respectively. Compound methyl 3-hydroxy-2-(2-(3-(4-methoxyphenyl)-4-oxo-3,4-dihydroquinazolin-2-ylthio)acetamido)propanoate exhibited the highest IC50 value 20 µg/mL against PC-3 cell line and scored the lowest free energy of the binding (-207.19 kJ/mol).

Anterior lamellar recession versus bilamellar tarsal rotation in upper lid cicatricial trichiasis.

PURPOSE: In recent years, there has been a significant shift from this destructive procedure to a reconstructive procedure such as anterior lamellar recession (ALR) and bilamellar tarsal rotation (BLTR). The aim is to report the outcomes and success rates of ALR compared to BLTR in patients with upper lid cicatricial trichiasis. MATERIALS AND METHODS: Our study is a prospective, interventional, comparative study that was conducted at the Ophthalmology Department of Al-Azhar University Hospital, New Damietta, Egypt. Our study was conducted on 62 eyes of 45 consecutive patients suffering from upper lid cicatricial trichiasis that required surgical intervention (17 patients were bilateral and 28 were unilateral). Thirty-three of them were treated by ALR (group 1), and 29 of them by BLTR (group 2). All statistical analysis was performed using the SPSS version 26. RESULTS: As regards the immediate postoperative correction, we found that adequate correction was significantly higher in the ALR group at all follow-up periods (P < 0.05). However, the overcorrection and undercorrection were significantly higher in the BLTR group (P < 0.05). Compared to the ALR group, the BLTR group saw a greater undercorrection at 1, 3, and 6 months (9.3%% vs. 0%; P = 0.048, 18.6% vs. 1.8%%; P = 0.009, 18.6%% vs. 1.8%; P = 0.009, 18.6%% vs. 1.8%; P = 0.009, respectively). CONCLUSION: ALR is better than BLTR in the treatment of upper lid cicatricial trichiasis.

Comparing the success rate of external dacryocystorhinostomy with anterior flap versus flap excision in managing chronic dacryocystitis.

Background: Nasolacrimal duct obstruction (NLDO) is characterized by epiphora and recurrent episodes of acute dacryocystitis. Despite the temporary effect of antibiotics in the acute phase, it is primarily managed by dacryocystorhinostomy (DCR). There is a new modification of external DCR that is performed without either anterior or posterior flaps. This study aimed to compare the outcomes of flapless and single-flap external DCR in adult patients with chronic symptomatic dacryocystitis secondary to NLDO. Methods: In this retrospective, non-randomized, interventional, comparative study of patients with chronic dacryocystitis secondary to primary acquired NLDO, we compared the surgical outcomes and complication rates of flapless external DCR to those of external DCR with only anterior flap suturing. We excluded patients who declined participation and those with soft stops, nasal problems, lid margin abnormalities, lid malposition or laxity, previous lacrimal surgery, lacrimal fistula, trauma involving the lacrimal drainage system, lack of adequate follow-up, or severe septal deviation or turbinate hypertrophy. Anatomical and functional success rates were determined at the last follow-up visit and were compared. Postoperative complications were recorded and compared between groups. Results: We included 53 patients with a male-to-female ratio of 16 (30.2%) to 37 (69.8%); 25 eyes underwent flapless DCR (group 1) and 28 eyes underwent anterior flap suturing DCR (group 2). The two groups had comparable demographic characteristics (all P > 0.05). Furthermore, anatomical (92.0% in group 1 and 92.9% in group 2) and functional (84.0% in group 1 and 92.9% in group 2) success rates at final follow-up were comparable between groups (both P > 0.05). At the one-month postoperative examination, premature tube extrusion was more often reported in group 1 (12.0%) compared to group 2 (7.1%). At the two-month follow-up examination, tube extrusion was noted in 4.0% in group 1 and 0.0% in group 2, yet the difference failed to attain statistical significance (P > 0.05). Conclusions: We found that neither surgical method was superior in terms of anatomical or functional success rate at a maximum of one year after external DCR. Flapless DCR is a simple, effective, and reproducible alternative to the single anterior flap suturing technique for managing NLDO in adults with chronic dacryocystitis. However, further randomized clinical trials with larger sample sizes and longer follow-up periods are recommended before generalization can be justified.

Development of a hypoxia-selective near-infrared fluorescent probe for non-invasive tumor imaging.

A near-infrared fluorochrome, GPU-311, was designed, synthesized and evaluated for its application in non-invasive imaging of tumor hypoxia. Efficient synthesis was achieved by nucleophilic substitution and click chemistry ring using the bifunctional tetraethylene glycol linker 2 containing thiol and azide groups for the conjugation of the propargylated nitroimidazole 1 and the heptamethine cyanine dye 3 bearing a 2-chloro-1-cyclohexenyl ring. GPU-311 exhibited long excitation and emission wavelength (Ex/Em=785/802 nm) and a decent quantum yield (0.05). The water solubility and hydrophilicity of GPU-311 increased. After in vitro treatment of SUIT-2/HRE-Luc pancreatic cancer cells with GPU-311, a higher level of fluorescence was observed selectively in hypoxia than in normoxia. However, in vivo fluorescence imaging of a mouse xenograft model after GPU-311 administration revealed inadequate accumulation of GPU-311 in tumors due to its rapid elimination through the liver.

Performance of Graphene-Based and Polyether-Ether-Ketone Polymers as Removable Partial Denture Esthetic Clasp Materials after Cyclic Fatigue.

The esthetic clasp material is a clinical demand for a satisfactory removable partial denture. The purpose of this study is to assess the mechanical performance of graphene-based polymer (GBP) and polyether-ether-ketone (PEEK) materials as clasp materials. Thirty-two clasps were fabricated by CAD-CAM from two materials, GBP and PEEK. All clasps were tested for retention force after 10,000 cycles of insertion and removal and thermocycling. The clasp arms' deformation was measured, and areas of stress−strain concentration were explored. The Mann−Whitney U test was used to compare the retentive force of the studied groups, while the independent sample t-test was applied to check the difference in clasp arm deformation at α = 0.5. The results showed a significantly higher retentive force (2.248 ± 0.315 N) in PEEK clasps, at p < 0.001. The deformation of the clasp arm of the GBP clasps was significantly higher than PEEK clasps. Areas of stress−strain concentration were seen at the junction of the retentive arm to the minor connector and at the retentive arm terminal. It could be concluded that PEEK polymer had a better mechanical performance as an esthetic clasp material than the GBP. An optimization study for GBP might be required to check the validity of such an application.

Biomechanical Performance of PEEK and Graphene-Modified PMMA as Telescopic Removable Partial Denture Materials: A Nonlinear 3D Finite Element Analysis.

PURPOSE: To assess stress and deformation in telescopic removable partial denture (RPD) frameworks manufactured with polyether ether ketone (PEEK) or graphene-modified polymethyl methacrylate (PMMA), as well as the stress of the underlying mucosa, via nonlinear 3D finite element analysis. MATERIALS AND METHODS: The 3D model of a full mandible was merged with a 3D-scanned Kennedy Class I model with bilaterally missing molars. The tissues, the telescopic crowns, and the RPD framework were designed and created using dental CAD software. The model was duplicated, and two materials-PEEK and graphene-modified PMMA-were assigned to the telescopic crowns and their frameworks. A force of 200 N was applied perpendicularly to the molars, and constraints were placed in the mandibular ramus and the inferior border. The generated von Mises stress and deformation of the frameworks, as well as the stresses of the telescopic crowns and mucosa, were also assessed. Statistical analysis of the differences between the tested materials was conducted via an independent samples t test at (α = .05). RESULTS: The von Mises stresses of the telescopic crowns and their frameworks in the graphene-modified PMMA model were significantly higher than in the PEEK model. In contrast, the deformation of the telescopic RPD framework of the PEEK model was significantly higher than the graphene-modified PMMA model. The stresses of the mucosa in both models showed an insignificant difference. CONCLUSION: PEEK material showed better biomechanical performance than the graphene-modified PMMA in telescopic RPDs.

Trueness of 3D printed partial denture frameworks: build orientations and support structure density parameters.

PURPOSE: The purpose of the study was to assess the influence of build orientations and density of support structures on the trueness of the 3D printed removable partial denture (RPD) frameworks. MATERIALS AND METHODS: A maxillary Kennedy class III and mandibular class I casts were 3D scanned and used to design and produce two 3D virtual models of RPD frameworks. Using digital light processing (DLP) 3D printing, 47 RPD frameworks were fabricated at 3 different build orientations (100, 135 and 150-degree angles) and 2 support structure densities. All frameworks were scanned and 3D compared to the original virtual RPD models by metrology software to check 3D deviations quantitatively and qualitatively. The accuracy data were statistically analyzed using one-way ANOVA for build orientation comparison and independent sample t-test for structure density comparison at (α = .05). Points study analysis targeting RPD components and representative color maps were also studied. RESULTS: The build orientation of 135-degree angle of the maxillary frameworks showed the lowest deviation at the clasp arms of tooth 26 of the 135-degree angle group. The mandibular frameworks with 150-degree angle build orientation showed the least deviation at the rest on tooth 44 and the arm of the I-bar clasp of tooth 45. No significant difference was seen between different support structure densities. CONCLUSION: Build orientation had an influence on the accuracy of the frameworks, especially at a 135-degree angle of maxillary design and 150-degree of mandibular design. The difference in the support's density structure revealed no considerable effect on the accuracy.

Optimization of Digital Light Processing Three-Dimensional Printing of the Removable Partial Denture Frameworks; The Role of Build Angle and Support Structure Diameter.

The optimal three-dimensional (3D) printing parameters of removable partial denture (RPD) frameworks should be studied to achieve the best accuracy, printing time, and least materials consumed. This study aimed to find the best build angle and support structures' diameter of the 3D printed (RPD) framework. Sixty (RPD) frameworks (10 in each group) were manufactured by digital light processing (DLP) 3D printing technology at three build angles (110-D, 135-D, and 150-D) and two support structures diameters (thick, L, and thin, S). Six groups were named according to their printing setting as (110-DS, 135-DS, 150-DS, 110-DL, 135-DL, and 150-DL). Frameworks were 3D scanned and compared to the original cast surface using 3D metrology software (Geomagic Control X; 3D Systems, Rock Hill, SC). Both printing time and material consumption were also recorded. Data were tested for the significant difference by one-way analysis of variance (ANOVA) test at (α = 0.05). The correlations between outcome parameters were also calculated. The 110-DL group showed the least accuracy. Significantly, the printing time of the 150-D groups had the lowest time. Material consumption of group 110-DS presented the lowest significantly statistical value. Printing time had a linear correlation with both accuracy and material consumption. Within the study limitations, the 150-degree build angle and thin diameter support structures showed optimal accuracy and time-saving regardless of material consumption.

IgG4-Related Dacryoadenitis in Egyptian Patients: A Retrospective Study.

Purpose: To report clinical, serological, and histopathological findings in Egyptian patients with dacryoadenitis associated with ImmunoglobulinG4-related disease (IgG4-RD). Methods: We retrospectively revised medical records of patients presented to Al-Azhar University Hospitals with lacrimal gland (LG) swelling between June 2016 and February 2022. We included patients with definite IgG4-related disease (IgG4-RD) diagnosis and excluded those with possible, probable, or unlikely IgG4-RD based on The Japanese Ministry of Health, Labour, and Welfare's 2011 guidelines. Results: Sixteen cases were included in the study (Fourteen females and two males, mean age 39.2±12.2 years); Seven cases met the criteria of Mikulicz disease, and nine cases met full clinical, serological, and histopathological criteria. Mean reported serum IgG was 1792.5 ± 313.7 (range 1063-2134) mg/dl, mean serum IgG4 was 576.25±215.3 (range 112-841) mg/dl, and mean Serum IgG4/IgG ratio was 31.9 ± 12.4%. The mean number of IgG4+ plasma cells/HPF was 74 ± 21.2, and the mean IgG4+ plasma cell percentage was 55 ± 9.7%. Serum IgG4 level showed a positive correlation to tissue IgG4+plasma cell percentage, while serum IgG4/IgG ratio positively correlated to both percentage and number of IgG4+plasma cells. Steroids had a good initial response, but recurrences were common. Conclusion: A considerable proportion of patients with lacrimal gland swelling fall within the range of IgG4-RD. Proper diagnosis requires clinical, serological, and histopathologic correlation. Patients require long follow-up periods.

Hormonal, follicular and endometrial dynamics in letrozole-treated versus natural cycles in patients undergoing controlled ovarian stimulation.

The objective of this study was to compare letrozole-stimulated cycles to natural cycles in 208 patients undergoing intrauterine insemination (IUI) between July of 2004 and January of 2007. Group I (n = 47) received cycle monitoring only (natural group), Group II (n = 125) received letrozole 2.5 mg/day on cycle days three to seven, and Group III (n = 36) received letrozole 5 mg/day on cycle days three to seven. There were no differences between the groups in endometrial thickness or P4 on the day of hCG. Estradiol levels had higher variation in the second half of the follicular phase in both letrozole-treated groups compared to the control group. Estradiol per preovulatory follicle was similar in both letrozole cycles to that observed in the natural cycles. LH was lower on the day of hCG administration in the letrozole 2.5 mg/day group vs. the natural group. In summary, letrozole results in some minor changes in follicular, hormonal and endometrial dynamics compared to natural cycles. Increased folliculogenesis and pregnancy rates were observed in the letrozole-treated groups compared to the natural group. These findings need to be confirmed in larger, prospective studies.

Transvaginal Doppler sonography for evaluation of irregular uterine bleeding with DMPA.

BACKGROUND: The main cause for discontinuation of depot medroxyprogesterone acetate (DMPA) use is irregular menstrual bleeding. The exact pathophysiological mechanisms of irregular bleeding have remained unclear. Transvaginal Doppler is a non-invasive method for studying changes in blood flow which may highlight the underlying pathology in those cases with irregular uterine bleeding. The aim of this study was to quantify the uterine and subendometrial microvasculature in DMPA users with irregular bleeding pattern in comparison to DMPA users with amenorrhea. STUDY DESIGN: This is a case control study. Forty users of DMPA were divided into two groups: one group included 20 users with irregular uterine bleeding and the second group included 20 amenorrheic users. Pulsatility index (PI) and resistance index (RI) of uterine and subendometrial blood vessels were determined. Power Doppler Energy was used to quantify the signal percentage of the subendometrial area. RESULTS: There is significant reduction of PI and RI in the uterine artery and subendometrial microvasculature in cases of irregular uterine bleeding. CONCLUSION: Irregular uterine bleeding with DMPA associated with increased perfusion of uterine and subendometrial blood vessels.

Evaluation of Bone-Implant Interface Stress and Strain Using Heterogeneous Mandibular Bone Properties Based on Different Empirical Correlations.

OBJECTIVES: The purpose of this study was to compare methods used for calculating heterogeneous patient-specific bone properties used in finite element analysis (FEA), in the field of implant dentistry, with the method based on homogenous bone properties. MATERIALS AND METHODS: In this study, three-dimensional (3D) computed tomography data of an edentulous patient were processed to create a finite element model, and five identical 3D implant models were created and distributed throughout the dental arch. Based on the calculation methods used for bone material assignment, four groups-groups I to IV-were defined. Groups I to III relied on heterogeneous bone property assignment based on different equations, whereas group IV relied on homogenous bone properties. Finally, 150 N vertical and 60-degree-inclined forces were applied at the top of the implant abutments to calculate the von Mises stress and strain. RESULTS: Groups I and II presented the highest stress and strain values, respectively. Based on the implant location, differences were observed between the stress values of group I, II, and III compared with group IV; however, no clear order was noted. Accordingly, variable von Mises stress and strain reactions at the bone-implant interface were observed among the heterogeneous bone property groups when compared with the homogenous property group results at the same implant positions. CONCLUSION: Although the use of heterogeneous bone properties as material assignments in FEA studies seem promising for patient-specific analysis, the variations between their results raise doubts about their reliability. The results were influenced by implants' locations leading to misleading clinical simulations.

Influence of Progressive Versus Minimal Canal Preparations on the Fracture Resistance of Mandibular Molars: A 3-Dimensional Finite Element Analysis.

INTRODUCTION: This study compared the residual tooth strength and stress distribution of a mandibular molar prepared with different variable tapered file systems using finite element analysis (FEA). METHODS: Two preaccessed mandibular molar TruTeeth (Endo 3DP; Acadental, Lenexa, KS) were subjected to simulated endodontic treatment in this study. One tooth was instrumented with ProTaper Gold (Dentsply Tulsa Dental Specialties, Tulsa, OK), and the other was instrumented with V-Taper 2H (SS White Dental, Lakewood, NJ). The 2 teeth were scanned using micro-computed tomographic imaging, and stereolithographic surface meshes were developed for FEA. Each model was subjected to a 200-N multipoint load-simulating mastication. The results of the FEA provided quantitative and qualitative measurements for von Mises stress distribution and total deformation. RESULTS: The maximum von Mises stress was greater in the ProTaper Gold-prepared model than the V-Taper 2H prepared model. In both models, total deformation values were highest in the clinical crown on the buccal aspect of the tooth. The highest stress values were found in the pericervical dentin, and stress decreased apically through the root. CONCLUSIONS: Within the limitations of this study, it can be concluded that the maximum stress values within the tooth prepared by ProTaper Gold were higher than those in the tooth prepared by V-Taper 2H. Canal preparation with the V-Taper 2H system preserves more pericervical dentin, which may increase the resistance to fracture.

Marginal Bone Level Changes and Oral Health Impact Profile (14) Score of Smokers Treated by Mandibular Mini Implant Overdentures: A 5-Year Follow-up Study.

OBJECTIVES: Studies considered edentulous patients having smoking habit as a compromised oral condition. This research examined the value of using mini implant mandibular overdenture to maintain long-term satisfactory levels of oral health quality of life and marginal vertical bone loss. MATERIALS AND METHODS: Twenty-nine edentulous patients with smoking habit received four mini implants in the mandible loaded by overdentures. The present study monitored patients radiographically for vertical bone loss after (1 month, 1, 3, and 5 years) of treatment. Patients were also evaluated by oral health impact profile 14 (OHIP-14) pretreatment and at 1 and 5 years of treatment. STATISTICAL ANALYSIS: Repeated measure analysis of variance with Bonferroni's test as a post-hoc test was used to see the difference among time points. Independent sample t-tests were used to compare between anterior and posterior mini implant positions after 5 years of follow-up. OHIP-14 questionnaire was analyzed by Wilcoxon signed ranks for pairwise comparisons at different evaluation times. A Holm-Bonferroni correction method was used to control the familywise error rate. RESULTS: The mean of the bone height changes showed a significant difference between 1-month data and all other evaluation intervals while no significance was calculated among other evaluation intervals. Bone loss of the mini implants placed anteriorly was less than those placed posteriorly with a statistically significant difference. A significant reduction in the OHIP-14 score levels was observed between pretreatment and both 1 and 5 years of treatment. No significance was seen between the first and fifth year after treatment. CONCLUSION: Mini implant overdenture could maintain satisfactory marginal bone level changes and oral health quality of life for patients with smoking habit after 5-year follow-up period.

The Significance of Buffer Solutions on Corrosion Processes of Cobalt Ferrite CoFe2O4 Thin Film on Different Substrates.

BACKGROUND: The spinel ferrite nanoparticles, such as zinc, nickel, and cobalt ferrites have exceptional electronic and magnetic properties. Cobalt ferrite nanomaterial (CoFe2O4) is a hard material that reveals high magnetic, mechanical, and chemical stability. AIM AND OBJECTIVE: The objective of this research is to predict the corrosion behavior of cobalt ferrite (CoFe2O4) thin films deposited on different substrates (platinum Pt, stainless steel S.S, and copper Cu) in acidic, neutral, and alkaline medium. MATERIALS AND METHODS: Cobalt ferrite thin films were deposited on platinum, stainless steel, and copper via electrodeposition-anodization process. After that, corrosion resistance of the prepared nanocrystalline cobalt ferrite on different substrates was investigated in acidic, neutral, and alkaline medium using open circuit potential and potentiodynamic polarization measurements. The crystal structure, crystallite size, microstructure, and magnetic properties of the ferrite films were investigated using a combination of XRD, SEM and VSM. RESULTS: The results of XRD revealed a cubic spinel for the prepared cobalt ferrite CoFe2O4. The average size of crystallites was found to be about 43, 77, and 102 nm precipitated on platinum, stainless steel, and copper respectively. The magnetic properties of which were enhanced by rising the temperature. The sample annealed at 800oC is suitable for practical application as it showed high magnetization saturation and low coercivity. The corrosion resistance of these films depends on the pH of the medium as well as the presence of oxidizing agent. CONCLUSION: Depending on the obtained corrosion rate, we can recommend that, CoFe2O4 thin film can be used safely in aqueous media in neutral and alkaline atmospheres for Pt and Cu substrates, but it can be used in all pH values for S.S. substrate.

Synthesis and antimicrobial activity of certain new 1,2,4-triazolo[1,5-a]pyrimidine derivatives.

Certain new derivatives of 1,2,4-triazolo[1,5-a]pyrimidines were synthesized through the reaction of 1,2,4-triazolo[1,5-a]pyrimidine-7-ol with ethyl bromoacetate to afford the ethyl acetate ester, which upon hydrazinolysis gives the corresponding hydrazide. The hydrazide is the key intermediate which was used for the synthesis of the target compounds. The structures of the new compounds were assigned by spectral and elemental methods of analyses. The synthesized compounds were tested for their in vitro antibacterial and antifungal activities. Most of the tested compounds showed comparable results with those of ampicillin and fluconazole reference drugs.