Dental Research Journal
Volume:11 Issue: 5, Sep 2014

All clinical decisions and research essentially begins with the review of pre-existing literature. It helps to make our clinical decisions based on an overview of all the literature concerning the particular clinical problem. This requires a lot of time and effort, which is becoming scarce in this day and age. Literature reviews shorten the time by offering relevant evidence in a concise form. However, narrative reviews might not be objective and unbiased. This drawback is overcome by systematic reviews. There is still some apprehension regarding undertaking systematic reviews due to lack of information. This article is an attempt to explain the concept of systematic reviews and methods used for conducting the same, which will be helpful in day-to- day clinical practice as well as research.

The purpose of this study was to determine the effect of three chewing gums and paraffi n on the remineralization and the hardness of demineralized enamel. A total of 12 subjects wore intraoral palatal appliances with two demineralized bovine enamel slabs. The study consisted of four experimental periods each lasting 21-days, during which subjects were assigned to one of three gum-chewing regimens: gum containing sorbitol, xylitol and a mixture of sorbitol and xylitol and with paraffi n as control. The appliances were worn during gum-chewing for 20 min and then retained for 20 min 4 times/ day. The slabs were subjected to energy dispersive X-ray spectroscopy analysis and surface microhardness measurements before in setting into the appliance and after the experimental period. The data were subjected to analysis of variance for repeated measures. A P < 0.05 was considered statistically signifi cant. Mineral analysis revealed no signifi cant difference between the baseline and after chewing periods for all groups (P > 0.05). No signifi cant difference was found among the groups either for the baseline measurements or after chewing periods (P > 0.05). All groups showed higher microhardness values after the chewing periods than the baseline except for the Vivident Xylit group (P < 0.05). The chewing of gum had no effect on the Ca/P ratio of demineralized enamel surfaces. The hardening of the demineralized enamel surfaces may vary according to the type of chewing gum.

Cone-beam computed tomography (CBCT) is a new imaging technology that has been widely used in implantology, oral and maxillofacial surgery and orthodontics. This method provides 3-D images that are composed of voxel, which is the smallest image unit, and determines image resolution. Smaller voxel is associated with the higher resolution and also greater radiation exposure. This study was aimed to fi nd out the effect of voxel size on the measurement of mandibular thickness. Using voxel sizes of 0.30 mm and 0.15 mm, two CBCT protocols (protocol 1: Field of view (FOV) of 15 cm, 85 kVp, 42 mAs, 0.15 mm voxel, 14 s scan time; protocol 2: FOV of 15 cm, 85 kVp, 10 mAs, 0.30 mm voxel, 14 s scan time) were carried out on 16 dry human mandibles with permanent dentition. Mandibular thickness was measured at seven different sites (midline region, bilateral canine regions, bilateral mental foramen regions and bilateral molar regions). Analysis of variance was used for analysis of data using the Statistical Package for the Social Sciences version 20 (SPSS Inc., Chicago, IL, USA). P < 0.05 considered to be statistically signifi cant. No statistically signifi cant differences were found between different protocols regarding the mandibular thickness (P > 0.05). Considering the insignifi cant differences of the mandibular thickness measurements using different voxel sizes, it would be more reasonable to use 0.30 mm voxel size instead of 0.15 mm voxel size to avoid unnecessary radiation exposure.

Despite the outbreak in dental science, oral and dental complications in Alzheimer are of the unsolved problems. It is assumed that tumor necrosis factor-α, which is a key factor in Alzheimer, has a relation with periodontal complications in patients with Alzheimer disease. The present study evaluated the effect of chronic periodontitis on serum levels of tumor necrosis factor-α in Alzheimer disease. This case-control study was performed on 80 patients with Alzheimer disease seeking medical care at Nour Hospital, Isfahan, Iran. Eighty patients with Alzheimer disease between 40 and 70 years old attended this study. Forty had chronic periodontitis (case group), and 40 patients had healthy periodontium (control group). Blood sample was taken, and serum levels of tumor necrosis factor-α were measured by means of an ELISA Reader device. Independent T-Test was used to analyze data, and P < 0.05 was considered signifi cant. The mean of tumor necrosis factor-α was 749.1 ng/μL in case group and 286.8 ng/μL in control group. Independent t-test showed that the mean of tumor necrosis factor-α in patients with Alzheimer and periodontitis was approximately three folds higher than the patients only with Alzheimer, and this difference was statistically signifi cant (P < 0.001). According to the results of this study, it seems that there is a difference between serum levels of tumor necrosis factor-α in patient with Alzheimer and chronic periodontitis and patients with Alzheimer disease and healthy periodontium. Tumor necrosis factor-α level in serum may act as a diagnostic marker of periodontal disease in patients with Alzheimer disease

Hyperlipidemia is a well-documented risk factor for coronary heart disease and a great wealth of clinical trials have shown that early detection of hyperlipidemia and prescribing drugs that lower elevated lipid levels reduce serious cardiovascular events, such as myocardial infarction, heart failure and stroke. Fordyce granules (FGs) are sebaceous glands without hair follicles, most often located under the epithelium of the cheek and the vermilion border of lip. The incidence of FGs is typically high and their presence is usually regarded as a normal variation of the oral mucosa. The aim of this study was to investigate the pattern of anatomical distribution and density of FGs and also to explore any potential relationship between the detection of FGs and the state of hyperlipidemia. A cross-sectional, prospective study was designed. The participants were divided into two groups; fi rst group consisted of individuals with FGs and the second group included those with no FGs detected. All participants were fasting 9-12 h before they were subjected to a comprehensive oral examination and their blood was sampled and tested for complete lipid profi le. The presence of FGs was scored based on the number of the granules and their anatomical distribution. Chi-square test was used and P < 0.05 was considered as signifi cant. A total of 350 patients were recruited for this study, nearly 90% (n = 314) elicit detectable FGs. The FGs were mainly located on the buccal mucosa with or without labial involvement and their density tend to reduce with age and also with smoking. Individuals with elevated lipid profi le tend to have the highest score of the FGs. According to this report, the presence of high numbers of FGs in people with high risk factors for cardiovascular disease should not be neglected.

Salivary gland tumors are relatively uncommon and they consist of 3-10% of head and neck neoplasms. Most of studies have shown geographic variation in the incidence and histopathologic types of salivary gland neoplasms. The aim of this study was to evaluate the salivary gland tumors in Isfahan for 10 years duration. In this epidemiological study, 229 medical records of patients with salivary gland neoplasms in Isfahan for 10 years duration (January 2001-December 2011) were reviewed. The clinical data and histopathological features were statistically analyzed using the Chi square, analysis of variance and Fisher tests; P < 0.05 was considered to be signifi cant. The data showed that salivary gland tumors were most frequent in women. The mean age of patients with benign tumors was 41.26 years and 51.83 years in malignant tumors. Out of 229 salivary gland neoplasms, 127 (55.5%) were benign and 102 (44.5%) were malignant. Most were in parotid (105), followed by the minor salivary glands (95), the submandibular gland (28) and the sublingual gland (1). Pleomorphic adenoma is the most common salivary gland tumor and mucoepidermoid carcinoma followed by adenoid cystic carcinoma are the most common malignancy of salivary gland tumors in Isfahan population. Although most of the results of this study were similar to those reported in other populations, some differences were observed.

The purpose of this study was to compare the push-out bond strength of mineral trioxide aggregate (MTA) and calcium enriched mixture (CEM) as root end fi lling materials. A total of 40 root dentin slices (1 ± 0.2 mm) were prepared from freshly extracted human maxillary central teeth and their lumens were enlarged to 1.3 mm. The slices were randomly divided into two groups (n = 20). MTA and CEM cement were mixed according to manufacturer’s instruction and introduced into the lumens. The specimens were wrapped in pieces of wet gauze soaked in distilled water and incubated at 37°C for 3 days. The push out bond strength was measured using a universal testing machine. The slices were then examined under a light microscope at ×10 magnifi cation to determine the nature of bond failure. The data were analyzed using Mann-Whitney test (P < 0.001). The mean push-out bond strength for CEM cement and MTA were 1.68 ± 0.9 and 5.94 ± 3.99 respectively. The difference was statistically signifi cant (P < 0.001). The bond failure was predominantly of adhesive type in MTA group and cohesive type in CEM group. CEM cement showed signifi cantly lower bond strength to the dentinal wall compared to MTA.

The aim of this study was to compare the accuracy of the apex-locating functions of DentaPort ZX, Raypex 5 and Endo Master electronic apex locators (EALs) in vitro. Thirty extracted human single-rooted teeth with mature apices were used for the study. The real working length (RWL) was established by subtracting 0.5 mm from the actual root canal length. All teeth were mounted in an alginate model that was especially developed to test the EALs and the teeth were then measured with each EAL. The results were compared with the corresponding RWL, which was subtracted from the electronically determined distance. Data were analyzed using a paired-samples t-test, a Chi-square test and a repeated measure analysis of variance evaluation at the 0.05 level of signifi cance. Statistical analysis showed that no signifi cant difference was found among all EALs (P > 0.05). The accuracy of the EALs was evaluated and all of the devices showed an acceptable determination of electronic working length between the ranges of ±0.5 mm.

The purpose of this study was to compare the occlusal peer assessment rating (PAR) index in Class I patients treated by means of Begg and Edgewise methods. The pre- and post-treatment study models of Class I patients, referred to two private clinics, treated with Begg method (n = 30) and standard Edgewise method (n = 30), were reviewed retrospectively using PAR index including dental displacements, buccal occlusion (anteroposterior, vertical and transverse), overjet, overbite and midline parameters. The changes in PAR indices were analyzed using paired t-test. A P < 0.05 was considered as statistically signifi cant. There was no signifi cant difference in sex and age distribution between the two groups. The improvement of buccal occlusion in patients treated by Begg method (1.51 ± 0.39) was signifi cantly higher than that of patients treated by Edgewise method (0.28 ± 0.39). The duration of treatment in Begg method (17.8 ± 1.3 months) was signifi cantly shorter than that of Edgewise method (23.7 ± 1.3 months). However, there were no signifi cant differences between the two methods in terms of total PAR index, dental displacements, overjet, overbite and midline. In conclusion, fi ndings of the present study indicated that Begg method might be associated with better improvement of buccal occlusion and shorter duration of treatment

Gingival overgrowth is a common side-effect of amlodipine regimen on the oral cavity. There is controversy regarding the cause and effect relationship of periodontal health and drug induced gingival overgrowth. Therefore, this study was conducted to investigate and to assess the relationship between the periodontal health and the onset and severity of gingival overgrowth in hypertensive patients receiving amlodipine. A total of 99 known hypertensive patients on amlodipine regimen were included in this study. Probing pocket depth (PPD) and clinical attachment loss (CAL) were noted on four sites of maxillary and mandibular anterior teeth. Gingival enlargement scores were assessed for each patient by employing the hyperplastic index. Oral hygiene status was evaluated using the calculus index (CI). Patients were divided into H, E and L groups based on their periodontal status and responders and non-responders based on their hyperplastic index scores. Differences in means of different periodontal variables in different groups were tested for signifi cance by using ANOVA and unpaired Student t-test. Pearson’s correlation coeffi cient was calculated to assess the\ correlation between different variables. For all analyses, P < 0.05 was considered to be signifi cant. All the periodontal parameters were statistically highly signifi cant (P = 0.00) amongst H, E and L groups and between responders and non-responders. Statistically highly signifi cant Pearson correlation coeffi cients were found between mean PPD and mean hyperplastic score, mean CAL and mean hyperplastic score and mean calculus and mean hyperplastic score. The results of this study indicated a defi nite association between periodontal health and development and severity of amlodipine-induced gingival overgrowth

The aim of this study is to evaluate and compare the crestal bone loss and stability of single mandibular posterior dental implants placed in immediate functional loading (IFL) and immediate nonfunctional loading (INFL) during 6 months after placement. Forty single piece root form titanium implants were placed in 20 patients using IFL and INFL techniques. The change in the level of crestal bone was measured on standardized digital periapical radiographs using SOPRO imaging software and stability of implants using resonance frequency analyser taken at the baseline, 1, 3, and 6 months. The measurements were statistically analyzed using the independent and paired t-test (P < 0.05, statistically signifi cant). The mean change in the crestal bone level from baseline to 6 months was signifi cant in both techniques. The implant stability quotient (ISQ) values at fi rst and third months were lower than those at the baseline for both the groups. However, the ISQ values at the sixth month were similar to baseline for both the groups. The crestal bone changes and the ISQ values when compared between the groups showed no statistically signifi cant difference. IFL of dental implants have equivalent results and success rate as that of immediately provisionalized implants within the limitations of this study.

Cryosurgery is one of the simplest, most effective gingival depigmentation methods. Repigmentation may happen after a while in each method. The aim of this study is to compare the recurrence rate after treatment by liquid nitrogen swap and a cryoprob in 18 months. A total of 26 patients with physiologic gingival pigmentation were selected. The anterior sextant was divided into left and right segments; each segment was treated randomly by swap technique or cryoprob. Standard photos were evaluated with photoshop software (Red, Green, Blue, Cyan, Magenta, Yellow, Black [RGB, CMYK]) before and at 2 week, 1,, ,, 12, 15, 18 months after the treatment. The results were compared, by the independent t-test and repeated measure ANOVA thereafter least signifi cant difference post-hoc. The viewpoints of patients and physicians regarding the treatment outcomes were obtained by a questionnaire and consequently evaluated qualitatively by McNemar test (P < 0.05 was considered as signifi cant level). The statistical analysis showed a signifi cant difference in color change after the treatment during 18 months, in each group (P < 0.001). The mean values of RGB had signifi cantly increased after 2 weeks in both methods (P < 0.001), but the differences from 2 weeks to 18 months after treatment were not signifi cant (P > 0.05). The mean values of CMYK signifi cantly decreased after 2 weeks in both methods (P < 0.001), but the differences from 2 weeks to 18 months after treatment were not signifi cant (P > 0.05). Qualitative evaluation showed the preference of the cryosurgery with swap method (P < 0.001). No signifi cant recurrence was observed during 18 months follow-up. Both methods of cryosurgery are appropriate in treatment of gingival depigmentation because no signifi cant recurrence was observed during 18 months follow-up.

Sealing ability is one of the most important features of endodontic sealers. The purpose of this in vitro study was to compare the sealing ability of a resin-based sealer with a mineral trioxide aggregate-based sealer. A total of 60 single-rooted extracted human teeth were randomly divided into two experimental groups (n = 25) and two control groups (n = 5). After canal preparation and smear layer removal, both groups were obturated with gutta-percha and sealer. Resin-based AH26 sealer was used in the fi rst group and Fillapex® sealer in the second group. Two layers of nail varnish were applied on tooth surfaces except for the apical 2 mm. In the negative control group, nail varnish was applied on the entire surface. The teeth were mounted according to Lima et al. study and then sterilized by ethylene oxide gas. The samples were evaluated for bacterial microleakage using Enterococcus faecalis (ATCC 29212) for 90 days. Data were analyzed by survival test (P < 0.05). Control groups had either immediate leakage or no leakage. The Fillapex® showed signifi cantly higher amounts of microleakage compared with AH26 sealer (P < 0.05) and both groups exhibited signifi cant differences in comparison with control groups. Both sealers had bacterial leakage. Sealing ability of AH26 was signifi cantly higher than that of Fillapex®.

Glass ionomer (GI) restorations exposed to fl uoride have the ability to slowly release fl uoride. Therefore, the aim of this study was to investigate fl uoride release from three GIs before and after exposure to sodium fl uoride (NaF) and acidulated phosphate fl uoride (APF). Fifteen disc-shaped samples (6 mm in diameter and 2 mm in thickness) from three GIs (Fuji II, Fuji IX, Chem Flex) were made and suspended in a polypropylene recipient containing 10 mL distilled water and stored at 37°C. At the 13th day, the samples of each GI were randomly divided into 3 groups. Groups 1 and 2 were exposed to NaF and APF gels for 4 min and group 3 served as control in distilled water. The fl uoride released was measured at day, 4, 10, 13, 14, 17, 20 and 23 by potentiometer. Data were analyzed by one-way ANOVA and Tukey test. P < 0.05 was considered as signifi cant. Fluoride release was highest after 24 h for the tested GIs, but Fuji II demonstrated the least amount. Fuji IX showed the highest fl uoride release followed by Chem Flex. Exposure to fl uoride gels signifi cantly increased fl uoride release for all materials (P < 0.05). The amount of fl uoride release for the three GIs was signifi cantly higher in APF groups during the test period. Highly viscous conventional GIs (Fuji IX and Chem Flex) released higher quantity of fl uoride.

Ameloblastoma has intrigued clinicians as well as pathologists due to its diverse clinical behavior and histomorphologic presentations. Keratoameloblastoma is a rare histologic sub type, characterized by extensive keratin formation within ameloblastic epithelium, with only a handful number of cases described in the literature. Here, we report a case of this uncommon sub type of ameloblastoma in a young female patient presenting as an extensive lesion in mandibular ramus area. The radiological and fi ne needle aspiration fi ndings suggested of a keratinizing cystic lesion and incisional biopsy showed features of ameloblastoma. Patient underwent segmental mandibulectomy and histological examination of excisional specimen revealed features of ameloblastoma with abundant keratinization leading to a diagnosis of keratoameloblastoma. The diagnostic pitfalls related with the lesion have been discussed along with a short review of the literature.

Maxillary sinus aplasia and hypoplasia are rare conditions that can cause symptoms such as headaches and voice alteration. The majority of patients are asymptomatic, but these conditions must be noticed for importance of differential diagnosis such as infection and neoplasms. Conventional radiographs could not differentiate between infl ammatory mucosal thickening, neoplasm, and hypoplasia of the sinus. Computed tomography (CT) and also cone beam computed tomography (CBCT) are the proper modalities to detect these conditions. In the present study, CBCT fi ndings of three cases with maxillary sinus hypoplasia and aplasia are reported.