Common risk factors for postoperative pain following the extraction of wisdom teeth

Vahid Rakhshan 대한구강악안면외과학회 2015 대한구강악안면외과학회지 Vol.41 No.2

The extraction of third molars is a common task carried out at dental/surgery clinics. Postoperative pain is one of the two most common complications of this surgery, along with dry socket. Knowledge of the frequent risk factors of this complication is useful in determining high-risk patients, planning treatment, and preparing the patients mentally. Since the risk factors for postoperative pain have never been summarized before while the risk factors for dry socket have been highly debated, this report summarizes the literature regarding the common predictors of postextraction pain. Except for sur- gical difficulty and the surgeon’s experience, the influences of other risk factors (age, gender and oral contraceptive use) were rather inconclusive. The case of a female gender or oral contraceptive effect might mainly be associated with estrogen levels (when it comes to dry socket), which can differ considerably from case to case. Improvement in and unification of statistical and diagnostic methods seem necessary. In addition, each risk factor was actually a combination of various independent variables, which should instead be targeted in more comprehensive studies.

The effect of functionalized SiO2 nanoparticles on the morphology and triazines separation properties of cellulose acetate membranes

Nasim Rakhshan,Majid Pakizeh 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.34 No.-

This study investigates the removal of triazines from an aqueous solution using a novel SiO2/CAnanocomposite membrane. The membranes were fabricated with phase inversion by dispersing SiO2nanoparticles in the CA casting solutions in the range of 0.01–0.1 wt.%. ATR-IR, FESEM, AFM, and contactangle analyses were employed to characterize the prepared membranes. The effect of silicananoparticles on the performance of membranes was studied through the pure water flux and MgSO4rejection obtained at an applied pressure of 10 bars. Nanocomposite CA membranes generally showedhigher salt rejection and experienced less flux than neat CA membranes, due to morphology changes. Inaddition, the observed salt rejection tended to enhance as silica loading increased up to a criticalconcentration. Three triazines (atrazine, propazine, and prometryn) were removed from water by theprepared membranes, and their rejections were compared. The results showed that the triazinesrejection was increased by pressure and feed concentration. The effects of the molecules’ properties,including molecular size, hydrophobicity and dipole moment, were studied. The results revealed that therejection of prometryn with a larger molecular size was always higher than the other two triazines. Itwas observed that there was a direct relation between dipole moment and triazine rejection, while thisrelation was not observed in the case of hydrophobicity.

The effect of chemical modification of SiO2 nanoparticles on the nanofiltration characteristics of polyamide membrane

Nasim Rakhshan,Majid Pakizeh 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.12

This study presents the synthesis and characterization of oleic acid (OA)-modified silica/polyamide (PA) nanocomposite membranes. The thin film composite (TFC) polyamide was prepared with M-phenylendiamine (MPD) and trimesoyl chloride (TMC) via interfacial polymerization over porous polysulfone. Five different thin film nanocomposite (TFN) membranes were fabricated by dispersing OA-modified silica nanoparticles in TMC solution. Chemical and thermal properties, surface morphology, roughness, film thickness and hydrophilicity of synthesized membranes were characterized by ATR-IR, TGA, FESEM, AFM, TEM and contact angle analysis. The results showed that incorporating OA-modified silica into thin film layer improved chemical and physical properties of nanocomposite membranes. The effects of modification of nano silica on pure water flux and MgSO4 rejection were investigated. OAmodified silica/PA membranes showed higher pure water flux in comparison with neat polyamide TFC membrane but lower than unmodified silica/PA membrane; while significant increase in salt rejection was exhibited for OA-modified silica/PA membranes. The maximum rejection for OA-modified and unmodified nanocomposite membrane was obtained about 98.7% and 95.2%, respectively.

Variations in surface roughness of seven orthodontic archwires: an SEM-profilometry study

Amini, Fariborz,Rakhshan, Vahid,Pousti, Maryam,Rahimi, Hajir,Shariati, Mahsa,Aghamohamadi, Bahareh The Korean Association Of Orthodontists 2012 대한치과교정학회지 Vol.42 No.3

Objective: The purpose of this study was to evaluate the surface roughness (SR) of 2 types of orthodontic archwires made by 4 different manufacturers. Methods: This in vitro experimental study was conducted on 35 specimens of 7 different orthodontic archwires, namely, 1 nickel-titanium (NiTi) archwire each from the manufacturers American Orthodontics, OrthoTechnology, All-Star Orthodontics, and Smart Technology, and 1 stainless steel (SS) archwire each from the manufacturers American Orthodontics, OrthoTechnology, and All-Star Orthodontics. Aft er analyzing the composition of each wire by energy-dispersive X-ray analysis, the SR of each wire was determined by scanning electron microscopy (SEM) and surface profilometry. Data were analyzed using the Kruskal-Wallis and Mann-Whitney U tests (${\alpha}$ < 0.05). Results: The average SR of NiTi wires manufactured by Smart Technology, American Orthodontics, OrthoTechnology, and All-Star Orthodontics were $1,289{\pm}915A^{\circ}$, $1,378{\pm}372A^{\circ}$, $2,444{\pm}369A^{\circ}$, and $5,242{\pm}2,832A^{\circ}$, respectively. The average SR of SS wires manufactured by All-Star Orthodontics, OrthoTechnology, and American Orthodontics were $710{\pm}210A^{\circ}$, $1,831{\pm}1,156A^{\circ}$, and $4,018{\pm}2,214A^{\circ}$, respectively. Similar to the results of profilometry, the SEM images showed more defects and cracks on the SS wire made by American Orthodontics and the NiTi wire made by All-Star Orthodontics than others. Conclusions: The NiTi wire manufactured by All-Star Orthodontics and the SS wire made by American Orthodontics were the roughest wires.

Two-year survival analysis of twisted wire fixed retainer versus spiral wire and fiber-reinforced composite retainers

Farhad Sobouti,Vahid Rakhshan,Mahdi Gholamrezaei Saravi,Ali Zamanian,Mahsa Shariati 대한치과교정학회 2016 대한치과교정학회지 Vol.46 No.2

Objective: Traditional retainers (both metal and fiber-reinforced composite [FRC]) have limitations, and a retainer made from more flexible ligature wires might be advantageous. We aimed to compare an experimental design with two traditional retainers. Methods: In this prospective preliminary clinical trial, 150 post-treatment patients were enrolled and randomly divided into three groups of 50 patients each to receive mandibular canine-to-canine retainers made of FRC, flexible spiral wire (FSW), and twisted wire (TW). The patients were monitored monthly. The time at which the first signs of breakage/debonding were detected was recorded. The success rates of the retainers were compared using chi-squared, Kaplan-Meier, and Cox proportional-hazard regression analyses (α = 0.05). Results: In total, 42 patients in the FRC group, 41 in the FSW group, and 45 in the TW group completed the study. The 2-year failure rates were 35.7% in the FRC group, 26.8% in the FSW group, and 17.8% in the TW group. These rates differed insignificantly (chi-squared p = 0.167). According to the Kaplan-Meier analysis, failure occurred at 19.95 months in the FRC group, 21.37 months in the FSW group, and 22.36 months in the TW group. The differences between the survival rates in the three groups were not significant (Cox regression p = 0.146). Conclusions: Although the failure rate of the experimental retainer was two times lower than that of the FRC retainer, the difference was not statistically significant. The experimental TW retainer was successful, and larger studies are warranted to verify these results.

Variations in surface roughness of seven orthodontic archwires

Fariborz Amini,Vahid Rakhshan,Maryam Pousti,Hajir Rahimi,Mahsa Shariati,Bahareh Aghamohamadi 대한치과교정학회 2012 대한치과교정학회지 Vol.42 No.3

Objective: The purpose of this study was to evaluate the surface roughness (SR) of 2 types of orthodontic archwires made by 4 different manufacturers. Methods: This in vitro experimental study was conducted on 35 specimens of 7 different orthodontic archwires, namely, 1 nickel-titanium (NiTi) archwire each from the manufacturers American Orthodontics, OrthoTechnology, All-Star Orthodontics, and Smart Technology, and 1 stainless steel (SS) archwire each from the manufacturers American Orthodontics, OrthoTechnology, and All-Star Orthodontics. After analyzing the composition of each wire by energydispersive X-ray analysis, the SR of each wire was determined by scanning electron microscopy (SEM) and surface profilometry. Data were analyzed using the Kruskal-Wallis and Mann-Whitney U tests (α < 0.05). Results: The average SR of NiTi wires manufactured by Smart Technology, American Orthodontics, OrthoTechnology, and All-Star Orthodontics were 1,289 ± 915 A˚, 1,378 ± 372 A˚, 2,444 ± 369 A˚, and 5,242 ± 2,832 A˚, respectively. The average SR of SS wires manufactured by All-Star Orthodontics, OrthoTechnology, and American Orthodontics were 710 ± 210 A˚, 1,831 ± 1,156 A˚, and 4,018 ± 2,214 A˚, respectively. Similar to the results of profilometry, the SEM images showed more defects and cracks on the SS wire made by American Orthodontics and the NiTi wire made by All-Star Orthodontics than others. Conclusions: The NiTi wire manufactured by All-Star Orthodontics and the SS wire made by American Orthodontics were the roughest wires.

The effect of time management education on critical care nurses’ prioritization: a randomized clinical trial

Fatemeh Vizeshfar,Mahnaz Rakhshan,Fatemeh Shirazi,Roya Dokoohaki 대한중환자의학회 2022 Acute and Critical Care Vol.37 No.2

Background:Nurses are at the forefront of patient care, and time management skills can increase their ability to make decisions faster. This study aimed to assess the effect of a time management workshop on prioritization and time management skills among nurses of emergency and intensive care units.Methods: This randomized clinical trial was performed with 215 nurses. The educational intervention about time management was held in the form of a workshop for the intervention group. The time management questionnaire was completed by both groups before, immediately after, and 3 months after the intervention.Results: Most participants were female (n=191, 88%), with a mean age of 31.82 years (range, 22–63 years). Additionally, the participants’ work experience ranged from 1 to 30 years (mean±standard deviation, 8.00±7.15 years). After the intervention, the mean score of time management increased significantly in the intervention group, but no significant difference was observed in this regard in the control group. The results also revealed a significant difference between the intervention and control groups regarding the mean score of time management 3 months after the intervention (P<0.001).Conclusions: Time management training helped nurses adjust the time required to perform and prioritize various tasks.

Preoperative imaging of the inferior alveolar nerve canal by cone-beam computed tomography and 1-year neurosensory recovery following mandibular setback through bilateral sagittal split ramus osteotomy: a randomized clinical trial

Ali Hassani,Vahid Rakhshan,Mohammad Hassani,Hamidreza Mahaseni Aghdam 대한구강악안면외과학회 2020 대한구강악안면외과학회지 Vol.46 No.1

Objectives: One of the most common complications of bilateral sagittal split ramus osteotomy (BSSRO) is neurosensory impairment of the inferior alveolar nerve (IAN). Accurate preoperative determination of the position of the IAN canal within the mandible using cone-beam computed tomography (CBCT) is recommended to prevent IAN dysfunction during BSSRO and facilitate neurosensory improvement after BSSRO. Materials and Methods: This randomized clinical trial consisted of 86 surgical sites in 43 patients (30 females and 13 males), including 21 cases (42 sides) and 22 controls (44 sides). Panoramic and lateral cephalographs were obtained from all patients. In the experimental group, CBCT was also performed from both sides of the ramus and mandibular body. Neurosensory function of the IAN was subjectively assessed using a 5-point scale preoperatively and 7 days, 1 month, 3 months, 6 months, and 12 months post-surgery. Data were analyzed using Fisher’s test, Spearman’s test, t-test, linear mixed-model regression, and repeated-measures ANCOVA (α=0.05, 0.01). Results: Mean sensory scores in the control group were 1.57, 2.61, 3.34, 3.73, and 4.20 over one year and were 1.69, 3.00, 3.60, 4.19, and 4.48 in the CBCT group. Significant effects were detected for CBCT intervention (P=0.002) and jaw side (P=0.003) but not for age (P=0.617) or displacement extent (P=0.122). Conclusion: Preoperative use of CBCT may help surgeons to practice more conservative surgery. Neurosensory deficits might heal faster on the right side.

Co-Expression of Putative Cancer Stem Cell Markers, CD133 and Nestin, in Skin Tumors

Sabet, Mehrdad Nasrollahzadeh,Rakhshan, Azadeh,Erfani, Elham,Madjd, Zahra Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

Background: Cancer stem cells (CSC) are populations of cells responsible for tumor initiation, progression and therapeutic resistance in many cancers. In the present study, we aimed to investigate the expression pattern and clinical significance of two CSC markers, CD133 and Nestin, in a series of skin tumors. Materials and Methods: One hundred and thirteen paraffin blocks from skin cancers including 16 (14%) cases of melanoma, 37 (33%) of squamous cell cancer (SCC) and 60 (53%) of basal cell cancer (BCC) were collected and assembled in a tissue microarray (TMA). The samples were immunohistochemically examined for the expression of CD133 and Nestin. Expression of these markers was also correlated with clinicopathological parameters. Results: A significant difference was observed in the expression of CD133 and Nestin in melanomas, SCC and BCC (p value=0.001). Furthermore, the level of expression was significantly higher in the melanomas compared to the SCC and BCC tumors. Expression of CD133 in the melanoma was significantly associated with increased tumor invasiveness (p value=0.05), a higher rate of metastasis (p value=0.04) and the presence of ulceration (p value=0.02). Increased expression of Nestin was observed in metastatic melanoma (p value=0.04), while no statistically significant correlation was found with other clinicopathological parameters including Breslow thickness, Clark level and ulceration. Conclusions: Elevated expression levels of CD133 and Nestin in the melanomas are associated with advanced disease, with more aggressive and metastatic skin tumors. Therefore, these markers could be potential therapeutic targets for malignant tumors of the skin.

Isthmuses, accessory canals, and the direction of root curvature in permanent mandibular first molars: an in vivo computed tomography study

Aria Chuppani Dastgerdi,Manizheh Navabi,Vahid Rakhshan 대한치과보존학회 2020 Restorative Dentistry & Endodontics Vol.45 No.1

Objectives: This study was performed to assess the anatomy of mandibular first molars. Materials and Methods: In this in vivo study, cone-beam computed tomography (CBCT) volumes of 312 bilateral intact first mandibular molars from 156 patients (79 men and 77 women; average age, 35.6 ± 11.2 years) were investigated in terms of the direction of each canal's curvature in the buccolingual and mesiodistal dimensions (direction of the position of the apex in relation to the longitudinal axis of the root), the presence of an isthmus (a narrow, ribbon-shaped communication between 2 root canals) in 3 segments (0–2, 2–4, and 4–6 mm) from the apex), and the presence and number of accessory canals (smaller canals besides the main root canals, connecting the pulp to the periodontium). Data were analyzed statistically (α = 0.05). Results: Mesiolingual canals were mostly buccally and distally inclined, while mesiobuccal and distolingual canals were mostly distally curved. Isthmuses were more common in younger patients (χ2 test, p < 0.05). The average numbers of accessory canals in the apical, middle, and coronal segments were 9.9 ± 4.2, 6.9 ± 2.9, and 9.3 ± 3.0 canals per segment, respectively (analysis of variance, p < 0.001). Age and sex were not associated with the number of accessory canals (p > 0.05). Conclusions: The complex anatomy of these teeth deserves attention during non-surgical or surgical endodontic treatment. Around the apex, isthmuses might be more prevalent in younger and female individuals.