Journal of Dental Medicine

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Normal 0 false false false EN-US X-NONE AR-SA Mesiodense have drawn attention of many researchers. According to the available data, there has not been any study on this issue in our country and due to racial variation in Iran, it is essential to evaluate the prevalence of mesiodense in our country. This article has evaluated this on 6-9 years students of Tehran. Complete evaluation is needed according to the lesions that mesiodense can bring about as well as prevention and treatment of this disorder and clinical care following diagnosis. Among 2686 randomly selected students ( 1128f/1559m) , 38 cases in boys and 5 case in girls were found. Therefore, the incidence rate was 5.5 times more in boys which is higher than the other published data. Prevalence of supernumerary teeth was 1.6% of which 88.3% were impacted and only 5.34% were located inversely. In Most cases(93%), single supernumerary teeth were founded.

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Normal 0 false false false EN-US X-NONE AR-SA One of the concerns od patients have been teeth stains particularly in anterior region. The etiology of this can be pulp necrosis, developmental disorders, drugs and systemic diseases. Bleaching or tooth whitening is a solution for some of these color changes. This article evaluated different methods of bleaching and their side effects . In case in which tooth whitening is needed,  attentive case selection should be done and advantages and disadvantages of each method should be considered in order to apply the best treatment among other options of bounding, veneering or crowning.

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Normal 0 false false false EN-US X-NONE AR-SA In order to evaluate occupational health in dentists of Tehran, 250 dentists ( 60f/190m) were selected. The results of our survey showed significant hearing loss in both ears of all the dentists mostly in 6 ghz frequencies. Urine analysis showed higher mercury levels in general practitioners than specialists Although this was not statistically significant. The majority of dentists refused to reply questions about occupational diseases. Only the younger generation of them with working experience of 5-9 years replied to all the questions of questionnaire.

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Normal 0 false false false EN-US X-NONE AR-SA Frenum or Frenulum is defined by Miller as a membrane joining two parts that causes movement limitation. Oral cavity frenums are : 1) labial frenums of maxilla and mandible which are also known as inhibition of lips. 2) lingual frenum of tongue located between central incisors 3) frenum in mandibular premolar area. Frenum can be one or double layered. If The attachment located in gingival line and alveolar mucosa and attached gingival, no complication is anticipated while higher locations to free gingival directions, it would be a high frenum that can cause periodontal and orthodontic complications and treatment relapse. Complete evaluation on bone destructions in central incisors area, diasthema and teeth mobility related to frenum should be carried out.

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Normal 0 false false false EN-US X-NONE AR-SA Two Root coverage methods of free gingival graft method (FGG) and coronally positioned flap (CPF) by using citric acid were evaluated in anterior mandibular labial site of 16 patients. The measurements were done before first FGG surgery, after FGG and two months following the second surgery. The results showed 1% improvement of root coverage after surgery while in two stage CPF method by using citric acid, significant effect of citric acid was obtained. The width of Keratinized gingiva changed to 6.25mm from 1.18mm which was statistically significant.

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Congenital vascular lesions occur most often in children. Parents of these children take them to maxillofacial surgeons directly or during the treatment of other complications such as infection or jaw bone disorders. Various terms now used are unable to describe the pathogenesis and mechanism of the effect of vascular lesions on growth and development of facial bone.  Term of hemangioma is used in almost all cases of congenital and acquired vascular lesions, while fibrosis or shrinkage occurs in some of these lesions over the time. There is also some confusion in describing the vascular lesions which primarily affected bones and soft tissue vascular malformations associated with changes in hard tissues.

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Today laser has a lot of usage in medicine and dentistry. In the field of dentistry, laser is used in soft tissue surgery, sterilization of canals (in root canal therapy) and in restorative dentistry laser is used for cavity preparation, caries removal, sealing the grooves (in preventive dentistry), etching enamel and dentin, composite polymerization and removal of tooth sensitivity. The use of Co2 lasers and Nd: YAG for cavity preparation, due to creating high heat causes darkness and cracks around the region of laser radiation. Also due to high temperature of these lasers, pulp damage is inevitable. So today, by using the Excimer laser especially the argon floride type with a wavelength of 193 nm, the problem of heat stress have been solved, but the use of lasers in dentistry, especially for cavity preparation needs more researches and evaluations.

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This syndrome is a genetical disorder with symptoms result from deficit in the formation of connective tissue, especially collagen fiber biosynthesis. In these patients, there is hyperelasticity and fragility of the skin and mucosa. Injuries sever bleeding, internal bleeding and hemartrosis may be seen in these patients. Wounds leave scars after healing. There is recurrent dislocation of the joints, especially knee and temporomandibular joints. Dentists should know the symptoms of this syndrome and its complications during dental treatments.

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Albright syndrome is a rare condition, usually appears in the early years of life and characterized by bending or thickening of long bones. In girls, of endocrine glands disorders especially precocious puberty are the most common symptoms. Also, Brown pigments in the skin are another sing of this syndrome. Certain mucosal and skin pigments are considerable features of the disease. Etiology and pathogenesis of this disease is not clear and various histopathologic patterns are observed. In fact, this disease is substitution of bone tissue with fibrous connective tissue in which various degrees of bone resorption and repair of the lesion is recognizable.

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Nowadays, due to recent developments and researches in dental science, it is possible to preserve and restore previously extracted cases such as teeth with extensive caries, fractured or less appropriate cases for crown coverage as well as teeth with external perforation caused by restorative pins. In order to restore the teeth with preservation of periodontium, we should know thoroughly physiological aspects of periodontium and protection of Biologic Width which is formed by epithelial and supracrestal connective tissue connections. Considering biologic width is one of the principal rules of teeth restoration, otherwise we may destruct periodontal tissues. Several factors are involved in placing a restoration and one of the most important ones is where the restoration margin is terminated. Many studies have been conducted on the possible effects of restoration margin on the gingiva and due to the results of these studies it was concluded that restoration margin should be finished supragingivally. However, when we have to end the restoration under Gingival Crest, First a healthy gingival sulcus is required. Also, we should not invade the biological width. Since a normal biologic with is reported 2 mm and sound tooth tissue should be placed at least 2 mm coronal to the epithelial tissue, the distance between sound tooth tissue and crown margin should be at least 4mm. Thus, performing crown lengthening is essential to increase the clinical crown length. Basically, two objectives are considered: 1) restorative 2) esthetic (gummy smile) Surgical procedure includes gingivectomy and flap procedure. Orthodontic procedure involves orthodontic extrusion or force eruption technique which is controlled vertical movements of teeth into occlusion. Besides, this procedure can also used to extrude teeth defects from the gingival tissue. By crown lengthening, tooth extraction is not required and furthermore, adjacent teeth preparation for placing a fixed prosthesis would not be required. Additionally, by remaining the tooth root, the alveolar bone is preserved and both esthetic and hygiene are extensively improved so the results would be much more satisfying.

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One of the most common outcomes of pulp inflammation is periapical granuloma formation. Existence of immune cells in these lesions showed involvement of both humoral and cellular immunity in the site. The presence of different antigens in the root canal causes production o various antibodies and consequent immunological reactions. Different theories have been proposed on periapical cysts. The most valid of them is based onimmunologic response which can lead to tissue destruction due to immunological reactions.

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Fanconi syndrome was first described in 1927 by G.Fanconi. Fanconi syndrome with congenital aplastic anemia is a hereditary disorder in which peripheral blood Pancytopenia and bone marrow hypoplasiais often associated with multiple somatic congenital malformations such as microcephaly, skeletal anomalies (absence or hypoplasia of radial or thumb or both of them), brown hyperpigmentation of the skin and vision, hearing, kidney, genital or central nervous system disorders. In addition, Heredity pattern is autosomal recessive. Average age of disease manifestation is 4-7 years in the first decade of life and male are two times more likely suffered than women. In fact, Developed Pancytopenia is usually responsible for death. The average life expectancy after diagnosis of Fanconi syndrome is approximately 5 years.

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The aim of this study was to evaluate mesiodistal diameter of permanent teeth and evaluating it's distribution in Iran. In current study, 850 plastery impressions or 16590 teeth were precisely measured by a digital coulis with 0.01 mm accuracy.The obtained measures of the permanent teeth are shown in table 1. Table (4) demonstrates the symmetry of left and right maxillary and mandibular teeth. Obtainedmeasurements in Table 1 were compared with Gran's measures (Table 2) which are shown in Table (3).Bolton analysis was done and results were found close to the BolType text or a website address or translate a document.ton measures. It was concluded that it is better to replace measurements of our society instead of Bolton's. Since we found minor difference with the measures of other researchers, especially for teeth anterior to first molar, using our measures in treatment plans would not bring about any problem.

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The microleakage of Cinaally amalgam, manufactured by Dr Faghihi Co. which is a high copper alloy and fine-cut amalgam was evaluated by radioisotope agents. The microleakage of cinaally amalgam was compared with Sybraloy amalgam, manufactured by Sybron/Kerr Co. which is a high copper alloy and spherical shape amalgam and is known as a standard amalgam alloy. The results showed that there is no statistically significant difference between microleakage of them after 24 hours, one month and two months.

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There has been a lot of development in the science of implantology since forty years ago when extensive research began on this field of science. The use of Dental Implantology has also increased in the last decade, which the main reason is the success of it. Recently some of our colleagues participate in short time Introductory and advanced courses of implant inside or outside the country and begin to use implants. Unfortunately, due to the insufficient period of time, there is no discussion of basic sciences of dental implantology. So we decided to partially fill this gap by writing this article.

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The aim of digital subtraction of radiographic images is eliminating the additional shades to increase the resolution and quality of the images. In dentistry, digital subtraction technique can be used for diagnosis of progressive periodontal diseases or evaluation of the amount of jaw bone repair or destruction. In this study, the possibility of digital subtraction with non-expensive techniques by the use of a personal computer has been investigated. To do so, first we prepared initial we digitalized the obtained radiographs by the use of a scanner. Then we tested the subtraction on two available scanner-specific soft wares which had the ability to digitally subtract the images. The results have been discussed in the full text of the article.

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Temporo Mandibular Joint disorders are the most important ethiologic factor for chronic orofacial pain and have a relatively new place in scientific researches and clinical studies in dentistry. Since dentists can play an important role in diagnosis and treatment of these disorders, routine dental examination should include functional examination of osteomatognatic apparatus.

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This study was conducted on the secondary school students by actively patient selection method it means that patients did not go to see the doctor themselves. The studies were randomly selected among the schools located in areas of average socioeconomic status. Although geographic and fissured tongue disorders with no discomfort and with clinical sign are common phenomena, they are detected and diagnosed in clinical and collective examinations. people recognition and awareness about them and what they should do when they occur with Syndromal signs are important. Patients usually complain of pain and irritation of the tongue specially during eating spicy and sour food, because the bare part of tongue cannot tolerate the direct contact with such foods. This chronic irritation may cause the fear of cancer (Cancerophobia) in patients. It should be pointed out that geographic tongue can be caused by known skin diseases like psoriasis or might be manifested as an allergic reaction to medicines like lithium. In this study we evaluated the relationship between grooved and geographic tongue and age, race, skin color, frequency of brushing, gum status, discomfort of tongue irritation and mouth breathing habit.

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Undoubtedly, Tooth decay is still one of the most significant problems in human communities. Tooth decay is defined as a microbial disease that causes demineralization of hard tissues and degradation of organic components of teeth. Although there are various theories on etiology of dental caries, Miller’s acidogenic theory (1890) and Gottileb’s proteolitic theory (1933) have gained the most credibility among the others. In general, status and amount of saliva, oral hygiene, tooth structure, type and quantity of microorganisms and diet are the most important factors that can lead to tooth decay. Since the manner and type of child nutrition during infancy is considered as a significant factor in development and progression of dental caries and also there has not been published any research on this subject in Iran yet, this study was designed and carried out to find the association between the type of milk intake in infancy and the rate of dental caries in 3-5 year old children.

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Malignant lymphoma is the neoplastic transformation of Cells, mostly originating from lymphoid tissues. Malignant lymphoma has two major subtypes: Hodgkin and non-Hodgkin lymphoma. Malignant lymphoma is the most common neoplasm in 3rd and 4th decades of life and more than two third of affected patients presented painless peripheral lymphadenopathy. Involvement of waldeyer’s ring, epitrochlear and mesenteric lymph nodes is more likely in non-Hodgkin lymphoma. Approximately 20% of patients with non-Hodgkin lymphoma have mediastinal adenopathy. Most often, these patients may suffer from persistent cough, chest discomfort or maybe referred without any complaint and just with an abnormal chest radiograph.