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Objectives: To investigate the effect of morphine as an exogenous opioid on orthodontic tooth movement. Naltrexone will be used as an opioid antagonist to confirm the results. Methods: Forty rats were randomly divided into four equal groups. The first group received no injection; the second group received daily injections of morphine; the third group received daily naltrexone-morphine injections and the fourth group daily injections of naltrexone-normal saline. The left first maxillary molar in each rat was tipped mesially with a NiTi closed coil spring. The rats were sacrificed after 14 days and the maxillae fixed, sectioned serially and examined histologically. Results: The greatest amount of tooth movement occurred in the Control group and the least amount of tooth movement in the Morphine group. Tooth movement in the Morphine group was significantly different from the other three groups (p < 0.05). The differences in tooth movement in the Control, Morphine-naltrexone and Naltrexonesaline groups were not statistically significant (p > 0.05). No statistically significant histological differences were found. Conclusions: Morphine reduced orthodontic tooth movement in rats. This effect was reversed by the opioid antagonist, naltrexone, which had no effect on tooth movement. [ABSTRACT FROM AUTHOR]

Periodontal ligament (PDL) cells play an important role in mechanosensing and secretion of signaling molecules during bone remodeling. However, the regulatory mechanism is unknown. The aim of the present study is to investigate the expression pattern of periostin and sclerostin in response to orthodontic forces in periodontal ligament cells in vitro. PDL cells were isolated from extracted teeth and treated with compressive forces of 25 gr/cm 2 or equiaxial tension forces at frequency 1 Hz for 0, 24, 48, and 72 h. qRT-PCR was applied to evaluate the gene expressions. The secretion of sclerostin and periostin was assessed using ELISA. DAPI staining was used to evaluate apoptosis. The expression of sclerostin elevated significantly at protein and gene levels under compression forces after 24 h, while the application of tensile forces induced the expression of periostin and its upstream regulator RUNX2 (p < 0.05). Gene expression up-regulation was significant for POSTN and RUNX2 after 48 and 72 h tensile forces. Also, the gene expression of sclerostin reduced in a time-dependent manner after application of tensile force. The compression forces enhanced apoptosis to 7.5 ± 3.5% and induced gene expression of apoptotic markers of CASP9, and BCL2 within 72 h of exposure. Periostin and sclerostin play an important role in orthodontic loads and their expressions are affected oppositely by compressive and tensile forces that might be suggested as a biomarker for assessment of bone remodeling during orthodontic treatment., (© 2023. The Author(s), under exclusive licence to The Society of The Nippon Dental University.)

One critical tactic that leads to a better understanding of the ethical status of dentists is to assess their ethical attitude by using an appropriate scale. This study aimed to design and evaluate the validity and reliability of the ethical attitude of dentists scale (EADS). This study was conducted based on a mixed-method design. The first qualitative part of the study was conducted in 2019 and the items of the scale were produced from the ethical codes compiled in a previous study. In this part, the psychometric analysis was conducted. The reliability was evaluated by Cronbach's alpha coefficient and intraclass correlation coefficient. Factor analysis was used to assess the construct validity (n = 511), and the following three factors were extracted with a total variance of 48.03. 1) Maintaining the standing of the profession in relationships. 2) Providing dental services while maintaining trust in the profession, and 3) Providing information for the benefit of the patient. In confirmatory factor analysis, appropriate values were obtained for the goodness of fit indices, and Cronbach's alpha was 0.68 - 0.84 for the various factors. Based on the results mentioned above, this scale showed an appropriate validity and reliability for measuring the ethical attitude of dentists., Competing Interests: The authors declare no conflict of interests., (Copyright © 2022 Tehran University of Medical Sciences.)

Statement of the Problem: The risk of debonding of the orthodontic eyelets due to blood contamination from the impacted tooth is a clinical problem that orthodontists face routinely., Purpose: This study aimed to assess the effect of hemostatic agents (Viscostat clear and Astringedent X) on shear bond strength (SBS) of orthodontic eyelets bonded with conventional (Transbond XT) and universal adhesive (GC-G Premio bond) adhesives., Materials and Method: In this experimental study, 84 freshly extracted bovine lower incisors were randomly divided into 7 groups namely TBXT, Blood, SEP, VISCO + TBXT, VISCO + SEP, ASTX + TBXT, and ASTX + SEP groups. In the TBXT group, teeth were etched with phosphoric acid gel, and then, the Transbond XT primer was applied and eyelets were bonded with Transbond XT. In the blood group, first, contamination with blood was done followed by the same procedure as TBXT. In other groups, the teeth were etched with phosphoric acid and based on their group allocation, Transbond XT primer (in TBXT groups), GC-G Premio Bond (in SEP groups), ViscoStat Clear gel (in VISCO groups), or Astringedent X (in ASTX groups) were applied. The SBS was measured for each group and the adhesive remnant index (ARI) was determined., Results: The mean SBS was 20.79 MPa in VISCO+SEP group, 19.2 MPa in the TBXT group, 16.06 MPa in the SEP group, 15.43 MPa in VISCO+TBXT group, 9.39 MPa in AST-X+TBXT group, and 1.62 MPa in the blood group. The SBS of ASTX+SEP, blood and TBXT+ASTX groups had significant differences from the SBS of the control group (p< 0.05). The ARI score of 0 had the highest frequency in the blood group., Conclusion: Due to the high coagulative effect of Astringedent X and acceptable SBS of Astringedent X in combination with GC-G Premio bond, this combination can be recommended for exposure of impacted teeth that are at high risk of blood contamination., (Copyright: © Journal of Dentistry.)

Background: The porous surface of acrylic orthodontic removable appliances creates a niche for microbial plaque accumulation, and changes the oral flora by raising cariogenic bacteria including Streptococcus mutans. In this study, we evaluated the mechanical properties and antimicrobial activities of incorporating different concentrations of Curcumin-Nisin-poly(L-lactic acid) nanoparticle (CurNisNps) into orthodontic acrylic resin against Streptococcus mutans and Candida albicans., Methods: Following synthesis and characterization of CurNisNps, acrylic resin specimens with different concentrations of CurNisNps (0, 1, 2, 5, and 10% w/w) were fabricated. Flexural strength values, antimicrobial effects, anti-biofilm potential, and anti-metabolic activity against S. mutans and C. albicans were assessed at different time intervals. Also, the expression of the virulence-factor-related genes of S. mutans and C. albicans was assessed by quantitative real-time polymerase chain reaction following treatment with CurNisNps., Results: Acrylic resin containing 10% CurNisNps (30.76 ± 3.91 MPa) showed flexural failure in comparison with acrylic resin specimens without CurNisNps (50.67 ± 1.82 MPa) as the control group (P < 0.05). There was no significant decrease in the flexural strength values in samples containing 1, 2, and 5% of CurNisNps in comparison to the control group (P > 0.05). Acrylic resin with 5% CurNisNps showed the highest concentration of CurNisNps and clinically accepted flexural strength value (14.89 ± 3.26 MPa, P < 0.05) simultaneously. In the disc agar diffusion assay, 5% CurNisNps showed a high level of inhibitory activity for the test microorganisms. The reduction of growth inhibition zones of the different concentrations of CurNisNps against test microorganisms was positively associated with the time, in such a way that it was reduced significantly after 60 days. The anti-biofilm and anti-metabolic activities of acrylic resin specimens containing a 5% concentration of CurNisNps against S. mutans and C. albicans could significantly decrease the expression levels of gtfB (6.8-fold) and HWP (3.4-fold) in S. mutans and C. albicans, respectively., Conclusions: Our data support that 5% (w/w) of CurNisNps can serve as an excellent orthodontic acrylic resin additive against S. mutans and C. albicans biofilm without adverse effects on its mechanical property., (© 2022. The Author(s).)

Background. Orthodontic tooth movement (OTM) occurs in the alveolar bone; therefore, any condition affecting bone quality can alter OTM. This study aimed to evaluate the effect of amitriptyline on OTM in rats. Methods. Forty-five male Wistar rats were randomly divided into three groups: (I) no injection, (II) injection with saline solution, and (III) injection of amitriptyline. Next, a 60-gr force was applied to the maxillary left first molar tooth of all the rats, using a nickel‒titanium closed-coil spring ligated between the maxillary incisors and the left first molar tooth. The rats were sacrificed after 21 days to measure OTM and perform histological analysis to determine the number, width, and depth of resorptive lacunae, osteoclast counts, and periodontal ligament (PDL) width. Results. The highest and the lowest OTM rates were found in the control and amitriptyline groups, respectively; however, there was no significant difference between the study groups in this regard. Histological analysis showed a significantly lower number of resorption lacunae in the amitriptyline group than the saline group. Conclusion. Although no significant difference was noted in OTM after amitriptyline administration, a reduction in the number of resorptive lacunae in rats injected with amitriptyline suggests that amitriptyline affects the bone tissue at the cellular level., (©2020 The Author(s).)

Objectives: The dental profession has a special place of trust in the society, and dental clinicians must adhere to ethical standards in all dental procedures. Ethical conduct is one of the main expectations of individuals from this profession. The aim of this study was to design and develop dental ethical codes for national implementation in Iran., Materials and Methods: This qualitative study was performed using directed content analysis method and purposive sampling. Data were collected until saturation through 15 semi-structured face-to-face individual interviews and two expert panels with academic staffs from dental faculties in Tehran, Iran., Results: Data were classified into five principles and 90 codes. The principles included consideration of patients' interest as a priority, respect for human dignity and patient autonomy, confidentiality of patient information, the excellence of knowledge and skills, and building trust., Conclusion: The ethical codes for Iranian dentists were drafted considering Islamic teachings and the prevailing culture. Some codes were exclusively developed for the cultural atmosphere of Iran especially on topics such as interaction with patients previously treated by other dentists. Some codes addressed the principles of consultation and continuing the therapeutic communication with such patients. Some items have not been considered in codes released by other associations, such as religious considerations in Islamic cover and alcohol consumption that were taken into consideration in this draft. These codes can serve as a guide for professional practice of dentists. It seems that these sets can help us reach the standardized code., Competing Interests: CONFLICT OF INTEREST STATEMENT The authors declare that there is no conflict of interests regarding the publication of this paper, (Copyright© Dental Research Center, Tehran University of Medical Sciences.)

Background and Objective: Urokinase-plasminogen activator (uPA) is a serine protease expressed at high basal level in normal gingival cervical fluid. Despite its known pathologic role in tissue proteolysis in periodontitis, little is known concerning uPA physiological function in oral tissue. Recent evidence in cancer cells has implicated the uPA system in DNA repair and anti-apoptotic pathways. This study is aimed to evaluate the protective function of urokinase against oxidative DNA damage in periodontal ligament (PDL) fibroblast, and to propose a new biological role for uPA in oral cavity., Material and Methods: PDL cells were isolated from human wisdom teeth obtained from healthy donors. An oxidative stress model was created in which PDL cells were incubated with 20, 30, 40 and 60 μmol/L hydrogen peroxide. Twenty-four hours before and after peroxide treatment, cells were treated with uPA and amiloride. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide assay, apoptosis by DAPI-staining and annexin V/propidium iodide assay, and DNA breaks by alkaline comet assay. For estimating DNA damage level, γ-H2AX expression was studied using flow cytometry and immunostaining., Results: The incubation of the peroxide-treated cells with uPA significantly increased cell viability and decreased apoptosis. A significant decrease in the number of γ-H2AX foci was seen at 30 μmol/L hydrogen peroxide in uPA-treated cells. uPA inhibition as a result of amiloride treatment, in turn, induced a reduction in cell viability. In addition, there was a significant decrease in the levels of DNA damage in uPA-treated groups as measured by the comet assay., Conclusion: The present study brings support to the theory that uPA may have a protective role for periodontal tissue and could protect PDL fibroblasts from oxidative DNA damage and apoptosis., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: Nitric oxide (NO) is a signaling molecule that mediates mechanical bone loading. Cyclic guanosine 3', 5' monophosphate (cGMP) is a NO-induced effector molecule. The aim of this study was to assess the effect of NO-cGMP pathway on orthodontic tooth movement (OTM) in rats by use of two phosphodiesterase 5 (PDE5) inhibitors namely sildenafil and tadalafil as chemical tools., Materials and Methods: Forty-five male Wistar rats were divided into three equal groups (n=15) based on the substance they received. The first group received daily injections of tadalafil; the second group received daily injections of sildenafil and the third group received daily injections of normal saline. The orthodontic appliances consisted of nickel-titanium closed-coil spring ligated between the maxillary right incisor and the first molar of the animals for 21 days. The amount of tooth movement was measured in all three groups at the end of this period. Histological analysis was performed to assess root resorption lacunae, osteoclast number and periodontal ligament (PDL) thickness., Results: All appliance-treated molars in the experimental and control groups showed evidence of tooth movement. The mean OTM was calculated to be 0.39±0.16, 0.32±0.16 and 0.26±0.16mm in tadalafil, sildenafil and control groups, respectively and there were no significant differences in OTM among the study groups (P>0.05). In the tadalafil group, significantly greater root resorption on the tension side was seen when compared with controls (P≤0.05)., Conclusions: Tadalafil and sildenafil PDE-5 inhibitors affecting the NO-cGMP pathway did not affect OTM in rats.

Objectives: Scientometric methods and the resulting citations have been applied to investigate the scientific performance of a nation. The present study was designed to collect the statistical information of dental articles by Iranian authors published in PubMed., Materials and Methods: We searched the PubMed database for dental articles of Iranian authors until June 31, 2015. All abstracts were manually reviewed in order to exclude false retrievals. The number of articles per dental subspecialties, distribution of research designs, Scopus/Google Scholar citation of each article, number of authors and affiliation of the first/corresponding author were extracted and transferred to Microsoft Excel. The data were further analyzed to illustrate the related scientometric indicators., Results: A total of 3,835 articles were retrieved according to the selection criteria. The number of PubMed-indexed publications between 2008 and 2015 showed a seven-fold increase. The majority of articles were written by four authors (24.56%). Systematic reviews and clinical trials constituted 9.20% of all publications. The number and percentage of articles with ≥4 citations from Google Scholar (n=2024; 52.78%) were higher than those from Scopus (n=1015; 26.47%). According to affiliated departments of the first authors, the top three dental subspecialties with the highest number of publications belonged to endodontics (19.82%), orthodontics (11.13%) and oral and maxillofacial surgery (10.33%). Moreover, the majority of articles originated from Shahid Beheshti- (14.47%), Tehran- (13.72%) and Mashhad- (12.28%) University of Medical Sciences., Conclusions: Analysis of PubMed-indexed dental publications originating from Iran revealed a growing trend in the recent years.

Introduction: The aim of this study was to assess the caries-preventive potential of carbon dioxide (CO 2 ) laser application in conjunction with the use of titanium tetra fluoride solution on the enamel adjacent to bracket. Methods: Seventy-five freshly extracted bovine incisors were used. In order to attach the brackets, the area of examination was covered with adhesive tape to limit acid etching of the entire enamel surface. Metal orthodontic brackets for upper central were bonded to all the teeth following the manufacturer's instruction. Then all the teeth were painted with 2 layers of acid-resistant nail varnish on all surfaces except the boxes area cervical to the brackets. The teeth were then randomly divided into five groups (n = 15): control group (C); laser group (L); titanium group (T); laser-titanium group (LT) and titanium-laser group (TL). The laser-titanium group was first irradiated with CO 2 laser (same as the L group) then TiF4 solution was applied on the enamel (same as the T group). Samples in the TL group were first treated with TiF4 solution (same as the T group) and then irradiated with CO 2 laser on the surface (same as the L group). Then, the teeth were immersed in pH-cycling solutions. After that, the amount of calcium released into the two solutions (de- and re-mineralization) was measured with an atomic absorption spectroscopy. The data were analyzed by one-way Analysis of var-iance (ANOVA) and Tukey test. Results: Calcium loss in LT, TL and T groups were significantly lower than those in the L and C groups ( P < 0.05). Conclusion: The application of Titanium tetra fluoride 4% solution on enamel can inhibit as much as 87% of subsequent caries like lesion progression.

Introduction: Osteoclasts and osteoblasts are responsible for regulating bone homeostasis during which the trace element zinc has been shown to exert a cumulative effect on bone mass by stimulating osteoblastic bone formation and inhibiting osteoclastic bone resorption., Objective: The aim of the present study was to investigate the effects of zinc (Zn) on orthodontic tooth movement (OTM) in a rat model., Material and Methods: A total of 44 male Wistar rats were divided into four groups of 11 animals each and received 0, 1.5, 20 and 50 ppm Zn in distilled water for 60 days. In the last 21 days of the study, nickel-titanium closed coil springs were ligated between maxillary right incisors and first molars of all rats, and tooth movement was measured at the end of this period. Histological analysis of hematoxylin/eosin slides was performed to assess root resorption lacunae, osteoclast number and periodontal ligament (PDL) width., Results: Mean OTM was calculated as 51.8, 49.1, 35.5 and 45 µm in the 0, 1.5, 20 and 50 ppm zinc-receiving groups, respectively. There were no significant differences in neither OTM nor histological parameters among the study groups (p > 0.05)., Conclusion: According to the results obtained in the current investigation, increase in supplementary zinc up to 50 ppm does not affect the rate of OTM neither bone and root resorption in rats.

Objectives: Fluoxetine is a selective serotonin re-uptake inhibitor (SSRI) widely used for depression, bipolar disorder, anxiety and obsessive-compulsive disorder. The aim of this study was to assess the effect of fluoxetine on orthodontic tooth movement (OTM) in rats., Materials and Methods: Forty-five male Wistar rats were randomly divided into three groups namely the control group (no medication), saline and fluoxetine dissolved in saline. In all groups, nickel titanium closed-coil spring was used between the left maxillary central incisor and first molar to exert 60g force at 2mm activation. Radiographs were taken at one and 21 days. After 21 days, the rats were sacrificed. The distance between the first and second molar teeth, optical density of bone, periodontal ligament (PDL) width, lacuna length and depth and number of osteoclasts were measured and compared among the groups., Results: Tooth movement significantly increased in the fluoxetine group (P=0.005). No significant differences were found in osteoclast count (P=0.069). The PDL width in the mesioapical region of root was significantly different among the groups (P=0.015). Statistical analysis did not show significant differences in depth or length of lacunae in any examined part of the root (P>0.05). Bone densitometry results showed that in fluoxetine group, density of bone in all four areas (alveolar bone, hard palate, skull and mandibular bone) significantly decreased from day one to day 21 (P< 0.05)., Conclusion: This study indicated that fluoxetine decreased bone density, which resulted in subsequently greater tooth movement in rats; however, further studies are needed on humans.

Low-level laser has been indicated to have the capability to facilitate the differentiation of the osteoclastic and osteoblastic cells which are responsible for the bone remodeling process. The aim of this study was to evaluate the effects of InGaAlP laser with a wavelength of 660 nm on the rate of tooth movement and histological status. Thirty male Wistar rats of 7 weeks old were selected for this study. The rats were randomly divided into two groups of 15 each to form the experimental (laser-irradiated) and control (non-irradiated) groups. The control group received unilateral orthodontic appliance design (one quadrant), but the laser-irradiated group received split-mouth design, with orthodontic appliance on both sides and laser irradiation on one side only (group b) and on the contralateral side (group c). The orthodontic appliance consisted of a NiTi closed coil spring with a length of 5 mm which was ligated to maxillary molar and incisor. A total of 60 g of force was applied to the rat molar. The diode laser (660 nm) was irradiated with an output power of 25 mW in continuous mode for a total time of 5 min in the laser-irradiated group. After 14 days of orthodontic tooth movement, the amount of tooth movements was measured. In the laser-irradiated group, the amount of tooth movement was significantly greater than that of the non-irradiated group (2.3-fold), but there was no significant difference between the non-irradiated and indirectly irradiated groups. Histopathological studies revealed that the number of osteoclasts in the laser-irradiated group was significantly greater than that of the non-irradiated group (1.5-fold) while this number was almost the same in the non-irradiated and indirectly irradiated groups. The results suggested that low-level laser can accelerate the rate of bone remodeling. However, in order to utilize the low-level laser as an adjunct in orthodontic practice on patients, further research studies are needed for finding the appropriate dosage for the human tissues.

Objectives: Health care workers, including dentists, are at the front line for acquiring blood-borne virus infections. This study aimed to investigate the prevalence of hepatitis B, hepatitis C and human immunodeficiency viruses among Iranian dentists., Material and Methods: The survey included 1628 dental health care workers who attended the 51st annual Congress of the Iranian Dental Association. Data on the risk of blood-borne virus transmission during health care and infection control practices were gathered from self-administered questionnaires. Sera were screened serologically by enzyme-linked immunosorbent assay (ELISA). The positive samples were examined by polymerase chain reaction (PRC) followed by direct sequencing., Results: Six (0.36%) and 81 (5.0%) were positive for hepatitis B surface antigen (HBsAg) and (anti-hepatitis B virus core antigen (anti-HBc), respectively. Only 1 (0.061%) was positive for anti-hepatitis C virus (anti-HCV). No case was positive for anti-human immunodeficiency virus (anti-HIV). One case was diagnosed as being occult hepatitis B virus (HBV) infection. One thousand five hundred thirty-five (94.3%) of participants had received at least 1 dose of HBV vaccine. One thousand three hundred fifty-nine (88.5%) contained hepatitis B surface antibody (anti-HBs) > 10 IU/ml, of whom 55 (4.0%) were anti-HBc positive, suggesting that they had been infected with HBV in the past. Anti-HBc positive cases had past histories of hepatitis, either their own or their spouses'. Individuals with inadequate anti-HBs levels (< 10 IU/ml) were significantly more prevalent among anti-HBc positive cases (p < 0.001)., Conclusions: The prevalence of blood-borne viruses among dental HCWs found in this study was lower than past reports from Iranian dentists and general population. The implementation of HBV vaccination together with improvement in infection control procedures has reduced the potential for risk infection among Iranian dentists., (This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.)

Background: Studies showed that HBV vaccination and consequent level of antibody are not completely adequate among dentists despite performance of highly exposure prone procedures., Objectives: The objectives of the study were to evaluate the levels of responsiveness to HBV vaccine and to determine the occupational factors associated among dental staff., Materials and Methods: In total, 1612 dental health care workers were recruited. The level of anti-HBs was tested using a commercially enzyme-linked immunosorbent assay (ELISA). Data on demographic, risk factors associated with dental practice and level of protective procedures and occupational exposure aspects were collected through self-reported questionnaires., Results: Of 1538 vaccinated individuals, 55 (3.7%), 126 (8.4%) and 1309 (87.9%) had received one, two and full three doses of vaccine, respectively. One-hundred-seventy-six (11.5%) were nonimmune (anti-HBs < 10 IU/mL) and 1362 (88.5%) were immune (anti-HBs > 10 IU/ mL). 392/542 (72.3%) of dentists who received their third dose of vaccination less than five years before the commencement of study were completely immune compared to those who had completed all three recommended doses in a longer period (308/491, 64.3%) (P = 0.001). Fifty-eight (3.59%) of participants did not receive any HBV vaccine at all; however, they had positive results for anti-HBs, indicating a past HBV infection. Statistically, the levels of anti-HBs were significantly associated with gender, age, duration of dental practice engagement and regularly use of mask, glasses and shield., Conclusions: Since dental care workers have a high risk of exposure to hepatitis virus, they should be advised to receive hepatitis B vaccine and it should be confirmed if they have acquired immunity to HBV by testing the level of anti-HBs.

Objective: Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin., Materials and Methods: Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting, hydrofluoric acid and silane. Maxillary incisor metal brackets were bonded to half of the disks in each group by conventional orthodontic bonding resin and the other half bonded with a nano-filled composite. The samples then were thermocycled for 2000 cycle between 5-55° C. Shear bond strength was measured and the mode of failure was examined. Randomly selected samples were also evaluated by SEM., Results: The lowest bond strength value was found infeldespathic ceramic bonded by nano-filled composite (p<0.05). There was not any statistically significant difference between other groups regarding bond strength. The mode of failure in the all groups except group 1 was cohesive and porcelain damages were detected., Conclusion: Since less damages to feldspathic porcelain was observed when the nano-filled composite was used to bond brackets, the use of nano-filled composite resins can be suggested for bonding brackets to feldspathic porcelain restorations.

Objective: The number of scientific papers is a conventional metric to measure a country's research performance in a particular area. The aim of this survey was to demonstrate statistical information about orthodontic research published in international and national journals., Materials and Methods: Pubmed as an international and IranMedex and SID as national databases were searched between1997 and 2012. The keyword searching method was used in English and Persian. Abstracts were reviewed and unrelated articles were omitted. Data were obtained and transferred to Microsoft Excel to survey the scintometric indicators., Results: According to the defined criteria, a total of 733 papers were found showing a considerable increase. Five hundred papers (68.2%) were published in domestic journals, and 233 (31.8%) were published in PubMed indexed journals. Most of the orthodontic articles originated from Shahid Beheshti University of Medical Sciences (22.9%). The Journal of Dental School, Shahid Beheshti University of Medical Sciences published most of the national papers (27.8%) and the Australian Orthodontic Journal published the majority of international papers (9.9%) In terms of study design, 52.5% of the articles were observational and 39.4% were interventional., Conclusion: Orthodontic research production in Iran has made significant strides in the recent years and researchers should focus on the quality of the study in this field in order to apply research production in evidence base dentistry.

Objectives: Statins are used as cholesterol-lowering drugs by many patients and have been recently shown to affect bone metabolism. The aim of this study was to determine the effect of atorvastatinon on orthodontic tooth movement (OTM) in rats., Materials and Methods: Thirty-six adult male Sprague-Dawley rats were randomly divided into three groups of 12 samples each. Group A, served as control with no medication while groups B and C received a daily gavage of carboxymethyl cellulose (CMC) as vehicle and atorvastatin (5 mg/kg) as test substance, respectively. In all three groups, 6mm nickel-titanium closed-coil springs were ligated between the maxillary incisors and first left molars to deliver an initial force of 60g. Tooth movement was measured following sacrifice, 21 days after appliance insertion. Root resorption, PDL width and osteoclast number were histologically evaluated and compared between the groups., Results: The mean amount of tooth movement was 0.62 mm in group A, 0.59 mm in group B and 0.38 mm in group C. OTM reduction following administration of atorvastatin was statistically significant (p<0.05), but there was no significant difference in the studied histologic variables among the three groups (p>0.05)., Conclusion: According to the results obtained in the current study, atorvastatin appears to reduce tooth movement in rats; however its effect on osteoclasts, especially osteoclastic function, requires further investigation.

Objective: The aim of this randomized controlled clinical trial was to investigate the effect of a new Iranian toothpaste and a commercially available toothpaste containing desensitizing agent (5% potassium nitrate) on dentine hypersensitivity in a 24-week study., Materials and Methods: Fifty healthy volunteers, who had at least two sensitive root surfaces, completed the study period. The participants were randomly given one of the two toothpastes; Iranian (antihypersensitive Pooneh) or commercially available (fresh mint Sensodyne) toothpaste. Visual analogue scales (VASs) indicating the intensity of tooth hypersensitivity responding to tactile, airblast and cold-water stimuli were examined at baseline and weeks 2, 4, 12 and 24., Results: Overall, VAS scores for tactile, airblast, and cold-water tests significantly reduced compared with the baseline in both groups (all P values <0.001). However, there was no significant difference between the two groups regarding the measured parameters., Conclusion: This study demonstrated that the Iranian dentifrice (antihypersensitive Pooneh) was as effective as the commercially available one (fresh mint Sensodyne) in reducing tooth hypersensitivity.

Objectives: Cephalometry and its related analyses have an important role in the evaluation of orthodontic patients. Access to an analysis that gives maximum information in the least possible time is an effective way to indicate craniofacial disharmony; therefore, craniofacial templates are very useful tools. The purpose of the present study was to provide orthodontic craniofacial templates for 8-14-year-old Iranian girls., Materials and Methods: One thousand two-hundred and nine girls (age range, 8-14 years) were examined. Eighty of these cases were finally chosen for the study and their lateral cephalograms were traced. Both Basion-Nasion (Ba-N) and Sella-Nasion (S-N) lines were selected for superimposition in this study. Based on these two mentioned lines, a template for each age was designed. Simple linear regression and multivariant regression analysis were used to evaluate the angles and to landmark the vectors, respectively., Results: Findings show that most points change significantly at different ages in the S-N method. In the Ba-N method, all points except for S and Ba have significant changes at different ages., Conclusion: Templates that resulted from both methods were the same and alteration in the reference line and points does not change the total form of the average tracings of each age.

Objective: Accurate prediction of the surgical outcome is important in treating dentofacial deformities. Visualized treatment objectives usually involve manual surgical simulation based on tracing of cephalometric radiographs. Recent technical advancements have led to the use of computer assisted imaging systems in treatment planning for orthognathic surgical cases. The purpose of this study was to examine and compare the ability and reliability of digitization using Dolphin Imaging Software with traditional manual techniques and to compare orthognathic prediction with actual outcomes., Materials and Methods: Forty patients consisting of 35 women and 5 men (32 class III and 8 class II) with no previous surgery were evaluated by manual tracing and indirect digitization using Dolphin Imaging Software. Reliability of each method was assessed then the two techniques were compared using paired t test., Result: The nasal tip presented the least predicted error and higher reliability. The least accurate regions in vertical plane were subnasal and upper lip, and subnasal and pogonion in horizontal plane. There were no statistically significant differences between the predictions of groups with and without genioplasty., Conclusion: Computer-generated image prediction was suitable for patient education and communication. However, efforts are still needed to improve accuracy and reliability of the prediction program and to include changes in soft tissue tension and muscle strain.

Objective: Tramadol is a synthetic analgesic of opioids which has more flexible mechanisms of action than typical opioids. Since it has been reported in previous study that typical opioids like morphine can affect the bone homeostasis, it is worthwhile to examine the effects of tramadol on tooth movement. In this study we investigated effects of tramadol on orthodontic tooth movement in rats., Materials and Methods: 30 male wistar rats were selected and received orthodontic appliance. 3 groups were designed based on the substance that they received daily injections of during a 2-week orthodontic treatment. 1. Control group with no injection.2.Control group with normal saline injection.3. the tramadol group. After the two-week treatment period the amount of tooth movement were measured in all the groups. Also the histological analysis was performed assessing the root resorption, osteoclasts numbers and bone resorption., Results: The amount of tooth movement was not significantl in the tramadol group comparing to the other groups (P>0.05).The results of 3 histological parameters (amount of root resorption, osteoclastic numbers and bone resorption) were statistically insignificant (P>0.05)., Conclusion: Tramadol as an atypical opioid does not interfere with the process of bone remodeling and tooth movement in rat. Tramadol does not affect osteoclastic activity and bone resorption and it does not cause to change the resulted root resorption either.

Templates are very useful tools for diagnosis of malocclusions. A number of templates have been provided for some populations in previous years. Since craniofacial characteristics of different ethnic groups are not the same, each population needs its own norms. The aim of this study was to provide orthodontic craniofacial templates for 8-16 year old Iranian boys and compare dentoskeletal features between Iranian and western populations. 3330 boys with the age range of 8-16 years were examined in Tehran, and 107 cases were finally chosen for the study and their lateral cephalograms were traced. Since there is no universal, consensus about the selection of one specific point or line for cephalometric superimposition, both the sella nasion (SN) and basion nasion (Ba-N) lines were chosen for this purpose. Based on both SN and Ba-N lines, a template was prepared for each age. Simple linear regression analysis was used to evaluate the angles and the multivariant regression analysis for evaluation of landmark vectors. Posterior cranial base, maxillary and mandibular lengths, upper and lower anterior facial heights (N-ANS and ANS-Me) and posterior facial height (S-Go) are greater in Iranian population. But anterior cranial base, height and inclination of the incisors and molar height are similar in two populations.

Objective: Attempts to treat class II malocclusions without extraction in non-compliant patients have led to utilization of intraoral molar distalizing appliances. The purpose of this study was to investigate dental and skeletal effects of Bonded Molar Distalizer (BMD) which is a simple molar distalizing appliance., Materials and Methods: Sixteen patients (12 girls, four boys) with bilateral half-cusp class II molar relationship, erupted permanent second molars and normal or vertical growth pattern were selected for bilateral distalization of maxillary molars via BMD. The screws were activated every other day, alternately. Lateral cephalograms and study models were obtained before treatment and after 11 weeks activation of the appliance., Results: Significant amounts of molar distalization, molar distal tipping and anchorage loss were observed. The mean maxillary first molar distal movement was 1.22±0.936 mm with a distal tipping of 2.97±3.74 degrees in 11 weeks. The rate of distal movement was 0.48 mm per month. Reciprocal mesial movement of the first premolars was 2.26±1.12 mm with a mesial tipping of 4.25±3.12 degrees. Maxillary incisors moved 3.55±1.46 mm and tipped 9.87±5.03 degrees mesially. Lower anterior face height (LAFH) decreased 1.28±1.36 mm., Conclusion: BMD is appropriate for distalizing maxillary molars, especially in patients with critical LAFH, although significant amounts of anchorage loss occur using this appliance.

Objective: The aim of this study was to evaluate the bond strength between metal brackets and non-glazed ceramic with three different surface treatment methods., Materials and Methods: Forty-two non-glazed ceramic disks were assigned into three groups. Group I and II specimens were etched with 9.5% hydrofluoric acid. Subsequently in group I, silane and adhesive were applied and in group II, bonding agent was used only. In group III, specimens were treated with 35% phosphoric acid and then silane and adhesive were applied. Brackets were bonded with light-cured composites. The specimens were stored in water in room temperature for 24 hours and then thermocycled 500 times between 5°C and 55°C., Results: The difference of tensile bond strength between groups I and III was not significant (P=0.999). However, the tensile bond strength of group II was significantly lower than groups I, and III (P<0.001). The adhesive remnant index scores between the three groups had statistically significant differences (P<0.001)., Conclusion: With the application of scotch bond multi-purpose plus adhesive, we can use phosphoric acid instead of hydrofluoric acid for bonding brackets to non-glazed ceramic restorations.

Introduction: The purpose of this study was to compare 2 common methods of measuring orthodontic shear bond strength., Methods: Brackets were bonded to 40 bovine incisors, and the teeth were mounted in a jig. The teeth were paired for symmetry, and the pairs were divided into 2 groups for debonding. In group 1, the shear force was applied with a rectangular wire under the tie wings. In group 2, a shearing blade applied force to the junction between the bracket base and the adhesive., Results: Debonding with the shear blade produced higher (24.86 +/- 7.44 MPa) and more dispersed (coefficient of variation = 29.91%) bond strengths compared with the wire loop (17.12 +/- 3.16 MPa, coefficient of variation = 18.44%). Adhesive remnant index (ARI) scores showed a tendency for cohesive failure in the enamel in the shear-blade group (ARI = 5) compared with adhesive failure (ARI = 3) in the wire group., Conclusions: There is a need to standardize bond strength tests. The results of this study favor the wire-loop method, which might have more similarity to clinical loads. The regression formula might make comparison of previous studies easier.