مجله دانشکده دندانپزشکی مشهد
سال سی و چهارم شماره 4 (پیاپی 75، زمستان 1389)

Most of Medical emergencies which take place in dental offices could be life-threatening. Thus, patient's preoperative examination and use of pain and anxiety controlling techniques can reduce these events. In this regard, the knowledge about these medical emergencies is of great importance and all of the dental staff should have sufficient knowledge in diagnosing and the way to manage them. This study aims to evaluate knowledge of dental specialists in diagnosis and treatment of medical emergencies. In this descriptive-analytical study, knowledge of dental specialists about common medical emergencies in dental offices, was assessed during 2009-2010. For this purpose, a questionnaire was designed and its reliability and validity was standardized. Forty-eight office-owner dental specialists answered the questionnaire and the recorded data were analyzed using descriptive analysis, Pearson correlation coefficient, student-t test, one-way ANOVA and Mann-Whitney through SPSS software. In this study, knowledge level of 54.2% of dental specialists was revealed to be good, 31.3% moderate and 14.6% was poor. The mean score did not show any significant difference in both sexes (P=0.124). Correlation between knowledge and age was negative which indicates that the rate of knowledge decreases in proportion to age, although this was not statistically significant (P=0.510). The result of this study revealed that the knowledge of dental specialists about diagnosis and management of dental emergencies did not prove to be satisfactory. Therefore, we suggest that more attention should be paid to this issue during postgraduate and general courses. In addition, educational courses for the dentists about approaches to medical emergencies in dental offices results in better knowledge of dentists towards these incidents.

Soft tissue opacities are almost common findings seen in panoramic radiography. These opacities include calcification of stylohyoid complex, tonsilolith, calcification of lymph nodes, carotid biforcation calcification, sialolith, rhinolith, antrolith, and myositis ossificant and osteoma cutis. The aim of the study was to report the prevalence of soft tissue calcifications in panoramic radiographs, their differential diagnosis, to determine risk factors and also to record and examine any symptoms observed. In this descriptive study, panoramic radiographs of 671 patients referring to the radiology department of Mashhad dental school were examined for one year and soft tissue calcification prevalence, their locations and some associated factors such as age, sex, marital status, risk factors and signs and symptoms were determined. The calcification of stylohyoid complex was measured. The data were analysed by chi-square and Fisher's exact tests. The pervalence of soft tissue calcifications was 58% for elongated stylohyoid process, 39.66% for tonsilolith, 25.86% for calcified lymph node, 8.62% for calcification for carotid bifbrcation, 6.90% for osteoma cutis, 5.17% for sialolith, 3.45% for calcified thyroid cartilage and 1.72% for antrolith. A significant correlation between the length of stylohyoid complex calcification and age was found (P<0.001). The study showed that styloid process greater than 45 mm should be considered as pathologic or suspicious calcification of stylohyoid complex. In addition, detection of calcified atherosclerotic plaque on panoramic radiographs should be regarded as an alarming factor for neurovascular accidents.

Restorative materials should be able not to strain under pressure during restoration process or mastication, so their mechanical properties are of high importance. The aim of this study was to evaluate the compressive and diametric tensile strength of hybrid and nanofilled composite restorative materials. Two hybrids (Diafil & Spectrum) and two nanofilled composite (nex com & synergy nano) were used in this in vitro experimental study. Samples were placed in a special circular mold and were light cured. After removing, the samples were stored in a light proof container under distilled water for 1 week. The specimens were then submitted to compressive and diametric tensile test, using universal compression machine at a crosshead speed of 1 mm/min. Data were analyzed using ANOVA and Duncan tests at significant level of 0.05. There was not any significant difference between the values of compressive strengths of the composites (P>0.05). Nex comp showed the least diametric tensile strength (P<0.05), but no significant difference was detected between the other three materials. Compressive strength of various composites was about the same, but diametric tensile strength of Nexcomp nanofilled composites was lower than other nanofilled or hybrid composites.

Tissue conditioners are used to provide time for healing of the irritated soft tissues under an old or ill fitting denture or as a diagnostic tool to assess patient's tolerance of new occlusal vertical dimension (VDO). The objective of this study was comparative evaluation of elastic strain, permanent strain and shore A hardness of 3 conventional tissue conditioners in Iran, namely Akrosoft, Softliner and Viscogel. In this experimental study, elastic strain, permanent strain and shore A hardness tests were accomplished for evaluation of physical properties of 3 conventional tissue conditioners in Iran, namely Akrosoft (Marlic Medical Ind. Co, Iran), softliner (GC company, Japan) and Viscogel (Densply Ltd, U.S.A). All of the specimens were mixed according to the manufacturer's instructions and exactly with the right powder to liquid ratio. Twenty-eight Specimens of each brand of mentioned tissue conditioners were mixed to add up to 84 specimens and restored in artificial saliva for 24 hours in room temperature for simulation of mouth conditions. Then 42 specimens (n=14), that is 14 specimens of each brand, were tested with durometer shore A hardness machine and the according numbers were recorded. The other 42 specimens (n=14) after restoring in artificial saliva for 24 hours in room temperature, were used for measuring elastic and permanent strain tests with Zwick machine. Finally, the data were analyzed by Kruskal-Wallis and Mann-Whitney tests. Statistical results from Kruskal-Wallis test showed that permanent strain in these three different groups was not different (P=0.463); however, elastic Strain and shore A hardness were statistically different (P<0.001 and P=0.007, respectively). Elastic strain and shore A hardness of the specimens also compared with two-by-two Mann-Whitney test were not statistically different. Shore A hardness of Viscogel specimens was significantly lower than Akrosoft and softliner specimens, but elastic strain of Viscogel was greater than both of them. It could be concluded that Viscogel is better from clinical standpoint.

Many lesions of the oral cavity have similar clinical features. Therefore, a confirmatory histopathological examination for final diagnosis and complete management of the lesions is necessary. The aim of this study was to evaluate the agreement between clinical and histopathological diagnosis in three groups of oral lesions during 30-years (1976-2006) in Mashhad Dental School.

In this retrospective study clinical and histopathological information from three groups of lesions (450 salivary gland lesions, 1058 odontogenic cysts and 195 odontogenic tumors) over a 30-year period was compared. Clinical data included age, gender, location of lesion and clinical diagnosis. Data were analyzed through SPSS 15 Software using t, and Fisher's Exact tests.

The clinical and histopathological diagnoses were compared by using the percentage of agreement and the percentage of discrepancy. Total agreement between clinical and histopathological diagnoses was 69.3%, 65.1% and 48.7% for odontogenic cysts, salivary gland lesions and odontogenic tumors respectively. Residual cyst, mucocele and odontoma showed the highest percentage of agreement in each of the studied groups.

It is concluded that in some cases, proper strategies and more attention to clinical feature of the lesion is necessary to minimize the discrepancy. However, lesions with nonspecific clinical presentation need oral pathology diagnostic service.

Orthognathic surgeries are used for correction of jaw discrepancies. One of the popular techniques in mandible is bilateral sagittal split osteotomy. The purpose of this study was to investigate sensory disturbance in lower lip up to 6 months after bilateral sagittal split osteotomy of mandible, and the effect of this sensory change on daily life of the patients as well as their level of satisfaction from the result of the operation. In this study, 22 patients (44 sides) with the average age of 21.4 years were operated with sagittal split osteotomy. For objective examination, 2-point discrimination test was done just before operation, and 3 and 6 months after the operation. For subjective examination, patients filled out questionnaires 3 and 6 months after the operation. Data were analyzed by Mc Nemar, Wilcoxon, t and Paired sample t-tests. In three month follow up, 63.3% and in six month follow up, 43.1% of cases had sensory changes. Wilcoxon test showed significant difference in the extent of anesthesia between three and six month follow ups (P=0.007) which showed recovery in regions with altered sense. The average result of 2-point discrimination test was 3.81 millimeters before operation, 6.9mm three months after operation and 5.2mm six months after the operation. In the six month follow up, the difference between right and left side was 1.04mm which was statistically significant (P=0.027). Despite the sensory changes in their lip, all patients were satisfied with the result of the operation. With passing the time (from 3 months to 6 months), the percentage of cases with sensory deficit decreased, which seems to be due to the spontaneous recovery of nerve. The results showed that sensory changes and their problems were not determinant factors in patient's satisfaction.

Ferric Sulfate has been proposed as an alternative to formocresol for pulpotomies in primary teeth, but it's success rate has been reported to be lower than formocresol pulpotomy in some literature. It may be in part due to Eugenol from Zincoxide engenol (ZOE) sub-base. The purpose of this study was to compare the clinical and radiographic success rate, of ferric sulfate pulpotomy of second primary molars using zinc oxide Eugenol (ZOE) or Mineral Trioxide Aggregate (MTA) cements as sub-base. In this randomized clinical trial study, approved by ethical committee of Mashhad University of Medical Sciences, 50 children aged between 3 and 5 years, each with two primary Mandibular second molars requiring pulpotomy were selected. After achieving haemostasis with damp cotton pellets, all of the teeth (100 teeth) were randomly allocated to one of the two groups of Ferric Sulfate pulpotomies: ZOE or MTA as sub-base. All of the teeth were restored with stainless steel crown. The teeth were clinically and radiographically evaluated double blindedly at 6 and 12 months after treatment. The data were analyzed using the McNemar test. Clinical success rate in one-year evaluation in two groups of ZOE and MTA cements were 97.5% and 100% respectively. No significant difference was found between the 2 groups. 83.3% of the samples in both groups showed no pathological signs on radiographic evaluation after 12 months. The most common radiographic sign of failure was furca radiolucency in both groups with frequency of 16.7% and 7.1% in ZOE and MTA groups respectively (P=0.344). The clinical and radiographic success rates of ferric sulfate pulpotomies of primary molars with MTA or ZOE as sub-base are almost the same.

Dentists and oral healthcare providers have a unique opportunity to motivate and help their patients to stop using different types of tobacco.There are many evidences that they can have a principle rule in prevention and treatment of many tobacco related oral and systemic diseases and repeated nature of dental services and relatively prolonged chair time provide multiple chances for informing, advancing and assisting patients in tobacco Cessation. On the other hand, it seams that they lack enough education in this area, leading to not adhering to this professional practice. This review provides a comprehensive discussion about the new published approaches for dentist's intervention in tobacco cessation programs.

Florid cement-osseous dysplasia (FLCOD) of the jaws is a multifocal dysplastic lesion of the bone trending toward mineralization and opacity. It is a member of a group of disorders originating from periodontal ligament tissue. This lesion is limited to the jaws and patients do not develop any evidence of bone disease in other parts of the skeleton. A majority of the lesions are asymptomatic and discovered in usual radiographs to be radiolucent or opaque. Incorrect diagnosis of the lesion leads to unnecessary root canal therapy in radiolucent stage and osteomyelitis after tooth extraction in opaque stage.

Two cases of florid cermento-osseos dysplasia are reported in this article. One case had been referred because of tooth mobility consequent to periodontal disease as well as for routine dental treatment and the other case referred with bone expansion.

Because of rarity of expansion as a symptom in this disease, it is accidentally observed in usual radiographs in different developmental stages. For avoiding of unnecessary or harmful treatments, recognition of this lesion is necessary for all dentists.