Original Article

D-1 Gene Polymorphism in Salivary Gland Tumors

Jannan Ghapanchi, Behnam Samavatian, Hamid Ghaderi, Bijan Khademi, Elham Mahmoudi Maymand, Elaheh Ainy

Journal of Dental School, Shahid Beheshti University of Medical Sciences, Vol. 37 No. 1 (2019), 21 September 2019 , Page 1-5

Objectives This study aimed to assess PD-1gene polymorphism in salivary gland tumors in patients referred to Khalili Hospital in Shiraz.

Methods This case-control study evaluated 48 patients with salivary gland tumors and 100 age- and sex-matched healthy controls. First, 5cc blood samples were obtained from patients and transferred to vials containing anti-coagulated EDTA. DNA was extracted, and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed on the samples. The PD-1 gene genotype was determined using the Fermentas kit. After 24 hours of incubation, all the samples were electrophoresed. The genotypes were reported based on the size of bands, and the chi-square test was applied. To compare the alleles, the Fisher’s Exact test was applied. The Yates correction was used to compare the genotype and genotypic alleles based on the tumor grade.

Results The mean age was 44.81±15.69 years in patients and 46.54± 13.86 years in controls. Statistical analysis did not show any significant difference in PD1 gene polymorphism between the two groups (P=0.098). No significant correlation was found between the genotype frequency and lymph node involvement (P=0.06), tumor genotype (P=0.12), side (right or left) (P=0.22), tumor location (P=0.27), and size or invasion of the tumor to the surrounding tissue (P=0.14). PD1.3 genotype frequency did not differ significantly between malignant and benign tumors (P=0.6).

Conclusion This study did not reveal any significant difference in genotype frequency of PD1.3 in the patient and control groups; however, further studies are needed with a larger sample size to obtain more accurate results.

Comparison of academic and nonacademic surgeons in treatment planning for CIII borderline case

Hoori Mirmohammadsadeghi, Amir Bayatian, Fatemeh Allahyari, Mahmood Dashti

Journal of Dental School, Shahid Beheshti University of Medical Sciences, Vol. 37 No. 1 (2019), 21 September 2019 , Page 6-10

Objectives In borderline class III malocclusions, the patients can be successfully treated by the orthodontic or surgical modalities, however; there is no consensus about the method with the best results regarding functional and esthetic parameters. The present study aimed to assess the treatment plans provided by academic and non-academic surgeons regarding borderline class III patients.

Methods In this cross-sectional descriptive study, diagnostic records of 20 borderline class III patients were assessed by 8 academic and 8 non-academic surgeons. The treatment plans suggested by the surgeons for patients were compared with the standard treatment plan based on case presentation. The data were analyzed by paired t-test, Wilcoxon test, Kappa coefficient, independent t-test and Chi-square test.

Results No significant differences were found between academic and non-academic orthodontists when suggesting orthodontic treatment (p=0.54), orthognathic surgery (p=0.1), single or double jaw orthognathic surgery (p=0.68) and the treatment plans in total (p=0.78) when compared with the standard treatment plan. The mean rate of agreement between the standard treatment plan and the academic and non-academic surgeons’ treatment plan for borderline class III patients was 75.0%±17.41% and 80.0%±17.73% for the orthodontic treatment plan, 80.0%±7.56% and 80.0%±17.73% for the surgical treatment plan, 70.55%±9.4% and 68.61%±9.08% for single or double jaw orthognathic surgery treatment plan, and 79.83%±7.76% and 80.63%±9.79% for the treatment plans in total, respectively.

Conclusion Academic and non-academic surgeons both showed higher agreements with the standard treatment plan when suggesting orthodontic and orthognathic surgery treatment plans for borderline class III patients.

Evaluation of Root Canal Morphology and Root Apex Anatomy of Mandibular Premolars in an Iranian Population: an ex-vivo study

Mandana Naseri, Mohammad Ali Mozayeni, Nahid Adelkhani, Atefeh Gohari

Journal of Dental School, Shahid Beheshti University of Medical Sciences, Vol. 37 No. 1 (2019), 21 September 2019 , Page 11-16

Objectives Adequate knowledge about canal anatomy is necessary for clinicians to prevent any damage to the periodontium. The aim of this study was to evaluate the canal and apical complexities of the mandibular first and second premolars in an Iranian population.

Methods One-hundred mandibular first (n=50) and second (n=50) premolars were collected. After access cavity preparation, 2% methylene blue was injected into the canals, and they were sealed with Coltosol and nail varnish. Next, demineralization and clearing with 5% nitric acid and methyl salicylate were performed. Apical morphology including the presence of accessory canals, apical delta, anastomoses and canal configurations was evaluated under a stereomicroscope at x16 magnification. Descriptive statistics (including tables, central tendency and dispersion tests) were used for data analysis.

Results The most prevalent form of canal type was Vertucci’s type I in first and second premolars. The mean distance between the apical foramen and anatomic apex, apical foramen and apical constriction, and apical constriction and anatomic apex was 0.3, 0.6 and 0.9 mm, respectively for the first premolars. These values were 0.3, 0.5 and 0.8 mm, respectively for the second premolars.

Conclusion Although most mandibular premolars have one canal, using appropriate cleaning methods is imperative because of high prevalence of accessory canals, anastomoses and apical deltas. First premolars pose more challenges in this respect

Comparison of salivary level of leptin in chronic periodontitis patients and healthy controls

Zeinab Rezaei Esfahrood, Mehrdad Ehghaghi, Ardeshir Lafzi, Zahra Yadegari, Maryam Kardan

Journal of Dental School, Shahid Beheshti University of Medical Sciences, Vol. 37 No. 1 (2019), 21 September 2019 , Page 17-20

Objectives Periodontal disease is an inflammatory condition of the tooth-supporting structures. Leptin is a hormone produced by the human body under different circumstances such as infection. It affects the production of cytokines, phagocytosis and the inflammation process. This study aimed to compare the salivary level of leptin in chronic periodontitis (CP) patients and healthy controls.

Methods In this case-control study, saliva samples were collected from 43 subjects including 22 CP patients and 21 healthy controls. The salivary level of leptin was determined using the ELISA. Data were analyzed by the independent t-test.

Results Despite the presence of leptin in the saliva of CP patients and healthy controls, no significant difference was noted in its salivary concentration between the two groups (p>0.05).

Conclusion The salivary level of leptin in CP patients was not significantly different from that in healthy controls. Further studies with larger sample size are required to confirm the results of this study

Intra-osseous Jaw Lesions in Children and Adolescents: A 20-Year Retrospective Study in an Iranian Population

Nasim Taghavi, Fahimeh Kooshki, Nafiseh Shamloo, Mohammadreza Hosseini

Journal of Dental School, Shahid Beheshti University of Medical Sciences, Vol. 37 No. 1 (2019), 21 September 2019 , Page 21-25

Objectives The aim of the present study was to document the frequency and clinicopathologic features of intra-osseous jaw lesions in an Iranian pediatric population over a 20-year period.

Methods Data were obtained from the archives of the Oral Pathology Department, Shahid Beheshti University of Medical Sciences, Tehran, Iran. The lesions were classified into four groups: (A) odontogenic cysts, (B) odontogenic tumors, (C) benign bone pathologies and (D) malignant bone tumors. The patients were divided into two age groups of (A) children (≤12 years old) and (B) adolescents (13 to 18 years old).

Results Of 5,722 biopsy samples, 475 (58.2%) were diagnosed as intra-osseous lesions in patients aged 0-18 years with a male (55.2%) and mandibular (60.6%) predilection. The patients’ age ranged from 3 months to 18 years with a mean age of 12.5 years. Odontogenic cysts presented the most prevalent subgroup (51.3%) followed by benign bone pathologies (26.5%), odontogenic tumors (18.9%) and malignant bone tumors (3.1%). The most frequently observed lesions in descending order were dentigerous cyst (25.2%), radicular cyst (18.3%), central giant cell granuloma (14.9%), ameloblastoma (7.7%) and odontogenic keratocyst (5%).

Conclusion Comparing our results with available data showed similarities in odontogenic cysts and benign bone pathologies. However, differences in odontogenic and malignant bone tumors were evident, which may be due to racial and geographical characteristics. Considering the limited data, further studies are recommended in this respect. 

Systematic Review

A Systematic Review of Methods Used to Assess Mid-Palatal Suture Maturation

Arezoo Mahdian, Shekoofeh Shaykhian, Mohammad Behnaz

Journal of Dental School, Shahid Beheshti University of Medical Sciences, Vol. 37 No. 1 (2019), 21 September 2019 , Page 26-31

Objectives Use of a reliable method to determine the degree of skeletal development of the mid-palatal suture is important in the choice of treatment between orthopedic maxillary expansion and surgical expansion in adolescents and young adults. The aim of this study was to review the new methods for evaluation of mid-palatal suture maturation.

Methods Electronic search was conducted in PubMed and Scopus databases using the following key words: (“mid-palatal suture maturation” OR “mid-palatal suture ossification”) AND (“orthopedic treatment” OR “maxillary expansion” OR “orthodontic*”) to find studies published from 1990 to December 2018 in English that evaluated the mid-palatal suture maturation stage.

Results Of 127 papers found, 28 articles met the inclusion criteria and their full texts were reviewed. Finally, 8 met the inclusion criteria. Five studies used cone-beam computed tomography (CBCT) as the imaging modality and examined the quality of the mid-palatal suture maturation and assessed the morphology of the suture. Two studies used bone density and one study used fractal dimensions.

Conclusion Since all the innovative methods lack a gold standard and valid histological references, it is not possible to reach a comprehensive conclusion. It is therefore important that the clinicians use several diagnostic criteria for thorough evaluation of the development of mid-palatal suture and decide on the appropriate therapeutic modality

Reviewed Article

Dimensional Accuracy of Polyvinyl Siloxane Impression Materials Considering Impression Techniques– A Literature Review

Nadia Nouri, Parviz Amini, Reza Amini, Mohammad Mousavi, Sajad Raeisi Estabragh, Abdola Ebrahimi

Journal of Dental School, Shahid Beheshti University of Medical Sciences, Vol. 37 No. 1 (2019), 21 September 2019 , Page 32-39

Objectives Impression accuracy is the main determinant of the fit, form and function of prosthetic restorations. Polyvinyl siloxane (PVS) is the material of choice in most clinical situations. The purpose of this paper is to provide an up-to-date review of scientific articles which discuss the dimensional accuracy of PVS impression material using various impression techniques, tray types and spacers. Besides, the procedure, advantages and disadvantages of commonly used impression techniques, technique modifications and innovations are also reviewed.

Method An electronic search of scientific papers from 1990 to 2018 was carried out using MEDLINE and Google Scholar databases using the search terms “accuracy and polyvinyl siloxane and impression technique” and “accuracy and addition silicone and impression technique”.

Results Searching the key words yielded a total of 312 articles. By application of inclusion and exclusion criteria, the obtained results were further reduced to 35 citations.

Conclusion Impression technique is a critical variable in the accuracy of PVS impressions. Dual-phase 2-step technique with 1 to 2 mm space for the light body is proven to be highly accurate and is still considered as the standard technique. The use of 2-step technique without providing a space for the wash material is rejected by the literature. Triple-phase 2-step techniques including “matrix impression system” have also functioned well and even superior to traditional dual-phase 2-step technique. Papers suggest that custom trays do not significantly improve the accuracy of impressions and rigid stock trays are suitable alternatives

Case Report

Orthodontic Management of a Severely Rotated Maxillary Central Incisor with a Modified Whip Appliance in Mixed Dentition Period

Neda Sinaee, Mohammad Mousavi, Nadia Nouri

Journal of Dental School, Shahid Beheshti University of Medical Sciences, Vol. 37 No. 1 (2019), 21 September 2019 , Page 40-43

Objectives Tooth rotation is one of the most prevalent dental anomalies. Early management of rotated teeth would prevent possible occlusal interferences. The purpose of this case report was to introduce a fixed-removable appliance, which can efficiently correct severely rotated anterior teeth in a short duration of time in mixed dentition period.

Case A 7-year-old boy with a Class I malocclusion was referred to the Orthodontics Department, School of Dentistry at Kerman University of Medical Sciences with the chief complaint of severe rotation of one of his maxillary central incisors. A whip appliance, which included a removable orthodontic appliance, a cantilever spring (whip) and a bonded tube, was used to treat this rotation. After 4 weeks, the upper right central incisor was aligned and overcorrected completely. A circumferential supracrestalfibrotomy was performed to prevent relapse.

Conclusion In the present case, we treated a severely rotated central incisor in a short duration of timeusing the whip appliance. This appliance can be utilized effectively in emergency situations such as traumatic occlusion of central incisors