مجله دانشکده دندان پزشکی اصفهان
سال هفدهم شماره 2 (پیاپی 75، تابستان 1400)

The aim of this study was the evaluation of compressive strength and setting expansion of GC and Adenta dye stones. Materials &

This study was an experimental study. The sample number was 21 for each group (n = 21). Compressive strength and setting expansion of GC and Adenta dye stones was done Based on ADA Standard 25 and Iranian Standard No. 2792. Data analysis was done with SPSS 20 software (p value = 0.05). The Independent-Sample t-test was used for data analysis.

There was no significant difference between GC (47.61 ± 5.54) and Adenta (44.31 ± 7.71) in terms of compressive strength. Also, there was no significant difference in the setting expansion between GC (0.07 ± 0.008) and adenta (0.08 ± 0.001).

Our results showed that there is no statistically significant difference in setting expansion and compressive strength between GC and Adenta dye stones and both samples was under standard condition) p value < 0.05).

 The purpose of this laboratory study was to investigate and compare the magnitude of the dimensional changes observed in the acrylic patterns under the influence of different times and conditions of storage.
Materials &

 This study was an experimental study. The sample number was 28 in 4 groups (7 samples each group). The resulting paste of acrylic samples was placed inside a metal mold and after setting time with the slightest of deformations it was removed. Using this method 28 samples were prepared for each material. The diameter of samples was then measured immediately using the digital caliper with a precision of 0.01 mm. The samples were then divided into four quadruple groups and stored at 22° C room temperature, 22° Cat water, Dry 4° C environment and 4° C water. The dimensions of the four groups were measured at intervals of 1, 8, 24, and 48 hours after polymerization and being removed from the metal molds. Data analysis was done with SPSS 24 software (p value = 0.05). The MANOVA test was used for data analysis.

 The findings of the current study showed that the dimensional changes of Duralay and GC acrylic resins at both 4 and 22° C in dry and water environments are decreasing over time (p value < 0.001). this study indicated that the contraction rate of two types of acrylic resins, Duralay and GC, at two temperatures of 4 and 22° C, and dry and humid conditions and at various times were not different. 

 dimensional changes in of the two types of acrylic resin, Duralay and GC, during the lapse, the procedure is going to be decreased but have not seen any statistical difference between these type of acrylic resin in environment storage.

Since orthodontic removable appliances might be infected with fungi and bacteria, they need to be cleaned using natural disinfectants and chemicals. This study aimed to compare the clinical impact of thyme essence and Fluconazole solution on the amount of Candida albicans colonies and Streptococcus mutans accumulated on the removable appliances in orthodontic patients.

In this descriptive-analytical study, 21 patients were selected who used the wear Hawley’s retainer for 24-hours. Patients were divided into three groups of seven. One group first washed the plaque with soap and water and then spray thyme essence all over it at a 5-centimeter distance (4 times on each side). In the other group, as before, the plaque was washed and from the same distance as before, the fluconazole solution (10 mg/ml) was sprayed on all surfaces 4 times. In the control group, the retainer was washed every night only with soap and water. After one month, the retainers were delivered form patients. The two samples were then separated from the Kami platelets and sent to a laboratory for microbial culture. Data were analyzed by Mann-Whitney, T-test (α = 0.05).

The use of thyme essence increases the mean area of Candida albicans inhibition, which was significantly higher than that in the control group (p value = 0.03). The effect of Fluconazole solution on this mean area) Candida albicans inhibition zone( was not significant compared to that observed in the control group (p value = 0.5). In the group in which thyme essence was used, the mean area of Streptococcus mutans inhibition, which was significantly higher than that in the control group (p value = 0.05). When Fluconazole solution was used, the mean area of Streptococcus mutans inhibition, was not significant compared to that observed in the control group (p value = 0.071).

Compared to Fluconazole solution, thyme essence functions more effectively in increasing Candida and Streptococcus mutans inhibition zones.

The daily use of orthodontic removable plates can interfere with the self-cleansing function of the mouth. Although various techniques have been proposed for cleaning removable orthodontic appliances, there is no consensus on the use of a safe method that preserves the physical properties of the appliance. This study aimed to investigate the effect of using hydrochloric acid (10%, for removal of mineral deposits) and sodium hypochlorite (5.25%, to remove organic matter and discolorations) on surface hardness and roughness of self-cure orthodontic acrylic resins.

This cross-sectional laboratory study was conducted in the fall of 2017 at Isfahan University of Medical science and Isfahan University of Technology. In this study two orthodontic acrylic resins (Orthocryl® and Acropars®) were used. Eighty samples (12×10×3 mm) from each one were fabricated and divided into four groups (n = 20). Group 1: 15 minutes immersion in household cleaner liquid (Hydrochloric acid, 10%) followed by15 minutes immersion in household bleach liquid (Sodium Hypochlorite, 5.25%). In group 2, immersions were repeated just like group two times and in group 3, were done three times. Group 4 was as control and had no immersion. The surface hardness and roughness of samples were measured. Data were analyzed with Two-Way ANOVA and the significance level was set at 0.05.

The number of immersion procedures did not significantly affect the surface hardness (p value = 0.958) and surface roughness (p value = 0.657) in the different study groups. There was no significant difference in the surface hardness between the two acrylic resin brands (p value = 0.077); however, Acropars acrylic resin samples exhibited significantly higher surface roughness compared to the Orthocryl acrylic resin samples (p value < 0.001).

15 minutes of immersion in 10% HCl, followed by 15 minutes of immersion in 5.25% NaOCl and repetition of the procedure three times did not significantly affect the surface hardness and roughness of self-cured acrylic resins.

This study aimed to evaluate the antibacterial and antifungal effect of Ag and zinc oxide nanoparticles to complete denture acrylic resin .

In this experimental laboratory study, 144 samples were evaluated. The powder of acrylic resin (PMMA Ivoclar Vivadent, Lichenstein SR Triplex Hot) was mixed homogeneously in the ultrasonic apparatus with Ag (purity: 99.99%, size: 20nm, spherical) and ZnO (purity: 99%, size: 10-30 nm, nearly spherical) particles with mass fraction 0.5, 1, 2 and 5. The microorganisms of this study were Candida albicans and Streptococcus mutans. The growth rate of microorganisms was measured by spectrophotometer based on turbidity and readings at 600 nm. Data were analyzed by SPSS 20 software. ANOVA and Tukey post hoc tests were performed. The significance level was set at 0.05.

increasing Ag and ZnO nanoparticles to acrylic resin reduced the growth of Candida Albicans and Streptococcus mutans. Even the concentration of 0.5% significantly reduced the growth of microorganisms. Complete growth inhibition was in the concentration of 5% after 24 and 48 hours.

Increasing the Ag and ZnO nanoparticles to acrylic resin reduced the growth of microorganisms.

 One of the simplest methods to predict mesiodistal width of permanent canines and premolars is using Tanaka and Johnston’s prediction formula; however, dental size varies according to race.  The study aimed to examine the relationship between incisors mesiodistal width and mandibular first molar’s with mesiodistal width of maxillary and mandibular canines and premolars and to determine the reliability of Tanaka and Johnston prediction formula. 

 In the present cross-sectional study, 200 pairs of a dental cast of 12-25 years old were selected and the greatest mesiodistal width of canines and premolars crown in each jaw and incisors and mandibular first molars were measured with a digital caliper with 0.01 resolution. Data were analyzed using regression analysis, t-test and SPSS 22 software. (p value < 0.05)

 there was a significant statistical difference between actual width and Tanaka and Johnston prediction formula in the group under study (p value < 0.001). Moreover, a new linear equation for the prediction of mesiodistal width of maxillary and mandibular canines and premolars based on mesiodistal width of lower incisors and mandibular first molars was developed using regression analysis.

 In statistical terms, Tanaka and Johnston’s prediction formula is not applicable for the population under study because maxillary estimated measures were a little high and mandibular estimated measures were a little low.

The placement of orthodontic separator induces pain and discomfort in patient. Use of Nsaid for its analgesic effect is with side effects. The aim of study evaluation of the effect of low level laser therapy on pain reduction and NO level in GCF induced by separator force in orthodontic treatment.

This experimental laboratory study was performed on 30 patients in the age range of 15-35 who required placement of the separator on the right maxillary molars. Patients were randomly divided into two groups of laser and placebo. Gingival groove fluid sampling was performed on 0-3-0 days in both groups. Laser irradiation was performed on days 2 and 4, in the placebo group, the device was used off. The amount of pain was recorded by patients with a VAS questionnaire on a daily basis. Data were analyzed by t-test and ANOVA (α = 0.05).

VAS score in laser group was more than placebo group but it wasn’t statistically different (p value = 0.067), NO level further decrease in laser group compared with placebo group but it wasn’t statistically different (p value = 0.286).

the effect of low level laser therapy on pain reduction was very low and it wasn’t statistically different.

Accidents are one of the most important cause of morbidity and mortality in different societies. One of the prevalent complications of crash and other accidents is maxillofacial fractures which in addition to abundant difficulties for patients has a high burden for health system of countries. So the aim of this study was analytical evaluation of financial burden of maxillofacial trauma with respect to demographic variables, therefore the costs of maxillofacial traumas were evaluated in Shiraz.

In this cross-sectional study, records of 200 patients hospitalized for maxillofacial trauma in Shiraz Shahid Rajayee hospital during 2018 to 2019 were evaluated. Costs of different parts of treatment, trauma mechanisms in addition to demographic characteristics (age and gender) were recorded for each patient. Data analysis was carried out by descriptive analysis.

Of total of 200 patients were hospitalized due to the maxillofacial injuries, 40 (20 %) were female and 160 (80%) were male. The age average was 39.9 years. The most common cause of trauma was crashes (81.5%). In average, 89272763 Rials was spent for each patient.

Results of the current study demonstrated that a huge budget is spent each year for accident patients whom have maxillofacial fractures.

Recurrent herpes labialis (RHL) is a common infection and occurs in 20 to 40% of the general population. Risk for transmission exists in dental treatments. There are several different treatments for it. The purpose of this study is a comparison between low-level Laser therapy (LLLT) and acyclovir cream for the treatment of it.

This performed study was a semi-blind clinical trial in the Oral Medicine Department, Dental School, Islamic Azad University Isfahan Branch (Khorasgan) in the year 2015-2016. 30 patients got divided into 2 similar groups. Patients in LLLT group, treated in 3 sessions every other day, received 660 nm laser irradiation, 100 mW, 4 J/cm2, continuous, located at a distance of 1 mm from the lesion for 40 seconds. Patients in the medication group treated with 5% acyclovir cream five times a day. In both groups severity of pain and lesion size during treatment and healing time recorded. The collected data were analyzed using statistical tests including Independent T-test and Repeated Measures ANOVA )p value < 0.05).

 The laser group had better statistically findings for the median time for pain relief (p value < 0.001), and the median time for healing (p value < 0.001), the median lesions size two days after treatment (p value = 0.03), and four days after treatment (p value = 0.003).

 According to data analysis, laser 660 nm is more effective in pain relief and lesions size reduction and healing time than topical acyclovir in patients with herpes labialis.

Surgical removal of mandibular third molars results in pain, swelling and bony defects, the growth factors present in platelet-rich plasma (PRP) can accelerate the healing, thereby shortening the postoperative recovery period. This study aimed, effect of platelet-rich plasma (PRP) on soft tissue healing after mandibular third molar surgery.

In this semi-blinded clinical trial study,30 selected patients requiring surgical extraction of soft tissue impacted mandibular third molar  participated from cases referred to the Department of Surgery, Faculty of Dentistry, Isfahan Azad University 2017.Patients divided into both test and control groups. PRP was placed in the extracted socket of the test group, whereas the control group had no PRP. Arzhangian standard kit utilized for preparation of PRP. The outcome variables in this study were pain, swelling, inter incisal mouth opening, wound dehiscence, dry socket, bleeding, and tissue color. The collected data analyzed using statistical tests followed independent T-test, Mann-Whitney, and fisher (p value < 0.05).

 The mean postoperative pain score (Visual Analog Scale) lowered for the test group after several wound dehiscence on the third and seventh days after surgery which was statistically significant (p value < 0.001). Although the mean bleeding time on the third day after surgery decreased in the test group, this difference was not statistically significant (p value = 0.59). There were no statistically significant between both groups for the dry socket incidence on the seventh day and the mean of inter incisal mouth opening in the third and seventh days after surgery as well.

The usage of topical PRP has beneficial advantages on soft tissue healing after mandibular third molar surgery. Unlike the control group, The PRP group provided reduced pain and better soft tissue healing.

Maxillary sinus augmentation and placement of dental implants is a well-established technique for functional and esthetic rehabilitation of partially or completely edentulous patients with severe maxillary atrophy. This study aimed to investigate dimensional changes of xenogarfts + allografts used for maxillary sinus augmentation in three directions and aspects of height, length and thickness by six months after sinus augmentation.

A total of 12 patients who underwent maxillary sinus augmentation by the approach of lateral window open sinus lift in Tehran university of medical sciences, and by application of xenografts + allografts were radiologically followed up and sequences of CBCT (Cone beam computed tomography) images taken immediately after graft placement and six months later. Data analyzed with Paired T-test in the 0.05 level of significance.

The calculated mean resorption in aspects of height, length and thickness of grafted materials after six months was 2.99, 2, 37 and 1, 72 mm. with SD of 2.64-1.41 and 1.95

In compared results of our study and other similar articles, it considered that directional changes of xenografts + allografts by six months after graft placement is mild to moderate, but it provides a reasonable density of new bone formation before implant placement.

 Medical errors include treatments that do not match approved standards in medical science and cause harm to the patients. This study aimed to investigate the frequency of complaints relating to pediatric dentistry in Isfahan province.

 This research is a descriptive, prospective, and cross–sectional study. Among 688 cases of dental complaint, of which data and documents collected in the medical council of Isfahan Province in 2008-2018, 14 identified cases of complaints were in the pediatric dentistry field, which then provided the needed data for research.

 The number of complaints in 2009-2011, 2013, 2014, and 2015 was one case, in 2012, 2016, two cases and in 2017 and 2018 were no reports. 5 were dental malpractices. 13 identified complainants were from patients' fathers, and 1 case was the mother among practitioners, were 50% men, 50% women, 29%pedodontists, and 50% general dentists. 2 of 4 complaints from pedodontists and 3 of 7 complaints from general dentists in the pediatric field recognized as malpractices.

 This study shows the number of pediatric malpractices is low in the Isfahan province. However, dentists must adhere to the medical oath and have good relationships with their patients. Supporting patients during treatment and considering their opinions and also treatment charges may lead to patients' satisfaction. Meanwhile, dentists should know about their abilities and their limits in practices. Also, they should refer complex cases to a specialist when they need to prevent further problems.

 Digital impression tools are an alternative to old impression materials and have developed significantly in recent years. These systems generally include two types of scanners: direct and indirect scanners. This article aimed to review and compare these two types of scanners.
Description: Data were collected by reviewing a total of forty articles on dimensional accuracy, a combination of scans, and internal and marginal gaps for comparison of direct and indirect scanners. These articles were retrieved from PubMed and Scopus and published between 2010 and 2020 using the following keywords: intraoral scanner, lab scanner, marginal gap, internal gap, and accuracy rate.

 Direct scanners had a lower amount of marginal and internal gaps, while indirect scanners had a lower deviation in more prepared teeth in the half and full arch due to the ability of stitching scans. Regarding the dimensional accuracy, the results of studies were inconsistent, but clinical studies pointed to the superiority of indirect scanners. The type of scanner suggested being selected depending on conditions such as the size of area, time, convenience of procedure, etc. The clinical results of both types of scanners were clinically acceptable.

Given the indefinite effect of antinucleoside drugs on the improvement of Recurrent Herpes Labialis, plant medicines such as Melissa officinalis have been proposed as a treatment of choice for these lesions. Clinical studies have reported different and conflicting results for the effect of Melissa on herpes. Hence, using a systematic approach, this study aimed to evaluate the clinical studies on the effect of Melissa on recurrent herpes labialis compared to acyclovir or placebo.

The English and Persian controlled clinical trials on the effect of Melissa on recurrent herpes labialis compared to acyclovir or placebo were investigated. Persian databases, including SID, Civilica, Medical Library, and Iranian Medical Sciences Theses and English databases content ProQuest, PubMed Google Scholar, were searched from 1990 to 2018 using a pre-designed strategy. Quality assessment of studies performed using the CONSORT-2010 checklist. The exclusion criteria of this study resemble details of both Persian and English searches/ articles, and eliminating one of them, in-vitro studies, and studies lacking an acceptable score by the CONSORT checklist. Out of 955 reviewed and evaluated articles from the 2010 consort checklist, 3 articles scored above 7.2 Articles were in English and 1 Article was in Persian. The search results were evaluated by the quality assessment of the recruited studies’ results. Compared to acyclovir and placebo, Melissa was more effective in reducing the lesion pain and size but had no significant effect on decreasing inflammation and erythema. The administration of the drugs did not provide any side effects.

Melissa was more effective than Acyclovir and placebo in reducing the lesion pain and size but did not significantly decrease inflammation and erythema.