Avicenna Journal of Dental Research
Volume:6 Issue: 1, Jun 2014

Context: Biocompatible polymers are potentially effective for dental infections as delivery carriers of disinfectants or antibiotics into the root canal system (RCS). This study aimed to review polymeric microspheres enabling a controlled release of endodontic medicaments..Evidence Acquisition: A literature search was carried out in the PubMed database (May 2013) using the following keywords: “poly lactic-co-glycolic acid or PLGA”, “polymer microplate”, “encapsulate”, “drug delivery”, “controlled release”, “antibiotic”, “gentamycin”, and “amoxicillin”. We intended to find articles on the application of polymer microparticles for delivery and release of drugs in dental infections or articles discussing factors affecting the properties of these materials.. Seventeen articles were found evaluating the controlled release of the drugs for dental purposes; out of them, in 5 in vitro studies, polymer microspheres had been produced for root canal disinfection. Seven articles had investigated the properties of polymer microspheres and the factors influencing drug release by them.. Drug-loaded polymer microspheres may be used successfully as delivery carriers for controlled release of antibiotics into the root canal system. The efficacy and success rate of this method must be tested in animal models and then clinical trials..

Accessibility to all sites of root canal and its mechanical and chemical cleaning is mandatory for successful root canal therapy. The presence of isthmus is a major hindrance to complete root canal accessibility.. The purpose of the present study was to determine the relative frequency and type of isthmuses in the apical region of mesial root of the first mandibular molar extracted in Yazd.. In this descriptive-laboratory study, 100 mandibular first molar teeth were collected. The mesial roots were excised at the cervical region and three horizontal sections perpendicular to the longitudinal axis of the root were secured with 1-, 3-, and 5-mm distances upwards from apex region of the roots. The incised surfaces were stained using India ink and viewed under stereomicroscope with a magnifying power of ×60 and photographed. The obtained images were studied regarding the presence or absence of isthmuses and the various anatomical forms of isthmuses were recorded based on Hsu & Kim taxonomy.. Isthmus was present in 54% of teeth. The greatest frequency of isthmuses was observed in the 5 mm from the apex. The type V isthmus was the most prevalent isthmuses between all levels of roots.. The frequency of isthmuses in the mesial root of mandibular first molars was high. The results of clinical and surgical endodontic procedures may be affected by this aspect of root canal anatomy..

Mechanical oral hygiene procedures are the most effective means of plaque removal and toothbrush is the most commonly used tool for mechanical plaque removal worldwide. There is an array of available manual and electric toothbrushes in the market. Thus, choosing the best one for dental plaque removal can be of great help for patients.. This study aimed at compare the efficacy of dental plaque removal using a manual and an electric toothbrush.. This experimental, single-blinded sequential clinical trial was conducted on 12 patients (ten females and two males) who aged 21 to 30 years old. The tested manual toothbrush was 35-mm soft Oral-B Pulsar and the electric one was Oral-B Professional Care 8500 DLX chargeable D18. Patients’ dental plaque score was set as zero through scaling, root planning, and polishing. Subjects were avoided tooth cleaning for three days and on day four, plaque accumulation was assessed using Tureskey''s modification of Quigley and Hein plaque index.. The mean of plaque index was 2.13 ± 0.83 and 2.11 ± 1.01 in the manual and electric toothbrush groups, respectively. No significant difference was detected between the study toothbrushes in terms of plaque removal (P = 0.374); however, with the manual tooth brushing, plaque removal was significantly greater in the buccal than in lingual surface and in the maxilla than in the mandible (P = 0.03 and P = 0.015, respectively).. Similar to previous studies, this study could not show the superiority of electric toothbrush over manual in plaque removal. After 72 hours, the mean of plaque index was greater in buccal than in lingual surface, which may be attributed to the natural cleansing action of the tongue..

Identification of common technical errors during preparation of panoramic radiographs, how affect the quality and interpretation of the radiographs and the techniques used to deal with such errors, might help prevent unnecessary radiation to patients and save their time and money.. The current study aimed to identify common errors in the panoramic radiographs taken by post-graduate students in the Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Hamadan University of Medical Sciences..Patients and A total of 220 conventional and digital panoramic radiographs of patients who were referred to the Department of Radiology were selected for the current study. All the radiographs had been taken by the post-graduate radiology students. The radiographs were evaluated by two oral and maxillofacial radiologists, under standard visualization conditions, to identify technical errors.. From the evaluated radiographs, 193 (87.7%) had one or more technical errors. The most common error was twisting of the head to one side (31.8%), followed by superimposition of the palatoglossus air space on the apices of maxillary incisors (30.9%).. The errors identified in the present study might be attributed to a lack of proper verbal communication between the patients and the post-graduate students, which necessitates continuous education of operators who take panoramic radiographs..

Aging causes many changes in human physiology, increasing the risk of pathologic conditions in elderly populations. Different studies have shown higher frequency of oral and maxillofacial lesions in older people. Knowing the prevalence and distribution of these lesions can help dentists in screening these patients.. This study aimed to evaluate the frequency and distribution of oral pathologic lesions among patients referred to Oral Pathology Department of Shiraz Dental School..Patients and By referring to archives of Oral Pathology Department of Shiraz University of Medical Sciences, the histopathological reports of all 231 patients aged 60 years or over were reviewed. The data were described and analyzed using SPSS software. Chi-square test was performed and a P value less than 0.05 was considered significant.. The most prevalent lesion was oral lichen planus (21.6%), followed by inflammatory fibrous hyperplasia (15.8%) and squamous cell carcinoma (7.6%). There was a statistically significant difference between men and women in the occurrence of odontogenic cysts and dermatologic diseases. (P = 0.018 and 0.002, respectively;chi-square =5.63 and 9.47, respectively).Moreover, non-neoplastic lesions were the most prevalent group of lesions in this study.. High frequency of life-threatening oral conditions among elderly populations makes it essential for dentists to pay special attention to the most frequent lesions and help enhance the life quality of elderlies by early diagnosis and management of these diseases..

Dental practitioners can be exposed to the human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) during routine work.. In this study, the knowledge, attitude, and practice of the dentists in Zahedan were examined on patients with HIV, HBV, and HCV infections.. This cross-sectional study was carried out on 100 dentists in Zahedan in 2013. A reliable and valid questionnaire on knowledge, attitude and performance of the dentists toward the infectious diseases of HIV, hepatitis B and C was distributed to all dentists who worked in Zahedan. Data were analyzed using one-way analysis of variance (ANOVA), independent sample t-test and Spearman rank correlation coefficient.. The mean score of the knowledge, attitude and practice of the dentists were 51.45 ± 3.16 out of 63, 20.22 ± 3.74 out of 39 and 64.41 ± 4.49 out of 72, respectively. Most of the participants (95%) believed that the fear and concern of the transmission of HIV, HBV and HCV infections are among the reasons of refusing the infected patients. The relationship between demographic variables and the level of knowledge, attitude, and practice of dentists was not statistically significant.. Although the dentists had a proper knowledge in the field of transmission of HIV, HBV, and HCV infections, fear and concern of being infected make them to refuse these patients. Therefore, training dentists to improve their attitudes toward treatment of these patients is necessary..

Trioxide Aggregate (MTA) has been widely used in root canal therapy. MTA has been mixed with chlorhexidine to increase its antimicrobial effect.. The aim of this study was to evaluate the effect of chlorhexidine (2%) on push-out bond strength of Mineral Trioxide Aggregate (MTA).. Sixty dentin disks with a thickness of 1.5 ± 0.2 mm and lumen size of 1.3 mm were prepared. Dentin disks were randomly divided into four groups (n = 15), and their lumens were filled with MTA mixed with distilled water (groups 1 and 3) or with chlorhexidine 2% (groups 2 and 4). Specimens were incubated at 37°C for 3 days (groups 1 and 2) or 21 days (groups 3 and 4). Bond strengths of the MTA-treated dentin surfaces were evaluated using a universal testing machine, and bond failure on the disks was examined by light microscope. Data was analyzed using Kruskal-Wallis H test (P = 0.976).. There were no statistically significant differences between all the experimental groups. The mode of bond failure was predominantly mixed for distilled water groups and cohesive for CHX groups.. This study suggested that chlorhexidine had no negative effect on the bond strengths of MTA-treated dentin..

Calcifying odontogenic cyst (COC) is a unique and uncommon odontogenic cyst classified into four groups of cystic, odontoma producing, ameloblastomatous proliferating and neoplastic ones.. A 34-year-old Iranian man complaining of a painless facial and palatal swelling of the left side of the maxilla persisted for approximately three years was referred to the department of oral and maxillofacial surgery, Hamadan University, Iran. Panoramic film revealed a well-defined multilocular mixed radiolucent and radioopaque lesion of the maxilla at the left side. An incisional biopsy was obtained. Based on the histopathologic findings, ameloblastomatous COC was diagnosed.. We reported a rare case of COC. According to Praetorius et al. classification, this patient comes under the category of type 1C (ameloblastomatous proliferating). Many patients with ameloblastomatous COC should be reported to understand its biological behavior as possible..