Avicenna Journal of Dental Research
Volume:13 Issue: 1, Mar 2021

Detailed knowledge of the three-dimensional (3D) anatomical structures in precise treatment planning prior to implant placement is necessary. The choice of imaging techniques plays an important role in achieving the required information to measure exact dimensions. Cone beam computed tomography (CBCT) has increasingly been used for diagnosis and treatment in the fields of periodontology, endodontic, and orthodontics. It is also used as the preoperative evaluation of patients who are candidates for dental implant treatment. Dental implant placement is an important application of CBCT in dentistry. One of the features of CBCT is the possibility of changing the slice thickness while reviewing images. In this study, we examined the linear measurement accuracy of CBCT for determining the height of alveolar crest to the mental foramen in cross-sectional view with different slice thicknesses and in tangential view.

We used five dry human mandibles in this study. Then the distance from the highest tip of alveolar crest to the upper border of mental foramen was measured by digital caliper (as gold standard) and on CBCT images in cross sectional view with 1, 3, 5, 7 and 9 mm slice thicknesses and in tangential view. Data were analyzed using IBM SPSS Statistics software version 22, paired t test, and inter class correlation.

Data were collected by evaluation of 5 dry mandible and 240 measurements. There were significant differences only in tangential view and 1 mm slice thickness option in cross-sectional view with the gold standard (P=0.003 and P=0.018 respectively). The results did not show any differences between the observers (P<0.001).

Our results indicated that cross-sectional view is more accurate than tangential view, and 3 and 5 mm slice thicknesses are preferred for measurement.

Microleakage is defined as the passage of bacteria, fluid, molecules or ions between the cavity walls and restorative material. There are limited studies in the literature that have compared the microleakage of the newer restorative materials. Therefore, the aim of this study is to compare and evaluate microleakage in Class II cavity in primary molars restored with glass ionomer cement, zirconomer and cention N using stereomicroscope.

Standardized Class II cavities were prepared on the extracted primary molars All the prepared samples were divided into 3 experimental groups and were restored as follows: Group I- GIC (GC Universal Restorative); Group II- Zirconomer (SHOFU Inc., Kyoto, Japan) and Group III- Cention-N (Ivoclar Vivadent). The restored teeth were thermocycled, immersed in methylene blue dye and sectioned along the mesiodistal direction. The dye penetration at the occlusal surface and cervical surface was evaluated and compared using a stereo-microscope. Data was analysed using KrushalWallis test (Non-parametric ANOVA).

Among the three restorative materials, Cention N as compared to GIC and Zirconomer showed least microleakage at both the occlusal surface and cervical surface.

Cention N a newer restorative material displayed lesser microleakage as compared to GIC and Zirconomer.

Periodontal disease is a common disorder in approximately 5%-10% of all pregnant women. The evidence suggests that periodontitis can increase the risk of preeclampsia. It seems that chronic systemic inflammation resulting from periodontal disease may be an important factor. However, some studies have ruled out any correlation between periodontal disease parameters and blood pressure. Therefore, this study was conducted to determine the correlation between periodontal disease and preeclampsia in Iranian pregnant women.

This case-control study was conducted on 40 randomly selected preeclamptic patients as the case group and 40 randomly selected healthy pregnant women as the control group aged up to 35 years with gestational age of less than 34 weeks. Preeclampsia was diagnosed by a gynecologist as sustained pregnancy-induced hypertension (BP≥140/90 mm Hg within 6 hours) with proteinuria (with urine protein concentrations ≥1 mg/dl on a catheterized urine sample). All the participants underwent periodontal examinations, including the measurements of the pocket depth (PD), clinical attachment loss (CAL), bleeding on probing (BOP), and plaque index (PI) in all the teeth except the third molar and second distal molar teeth. Statistical analysis was performed using the Mann-Whitney U test and P<0.05 was considered as statistically significant.

The results showed that prevalence of periodontal disease was significantly higher in the preeclamptic group. The quantitative analysis of periodontal parameters between the groups indicated that mean values of the BOP, CAL, PD, and PI were significantly higher in the preeclamptic group, compared to those reported for the control group (P<0.001).

The results of the present study showed that periodontal indices are more severe in pregnant women with preeclampsia, compared to those reported for normal pregnant subjects.

This study aimed to assess the effects of calcium hydroxide, Biodentine, calcium-enriched mixture (CEM) cement, and mineral trioxide aggregate (MTA) on root dentin flexural strength after a 30-day exposure period.

This in vitro experimental study evaluated 25 freshly extracted sound human incisors with no caries or restorations. The apical 5 mm and the coronal two-thirds of the crowns were cut such that all samples had 10 mm length. Dentin samples (n=20 in each group) were then exposed to 2 mm thickness of calcium hydroxide, Biodentine, CEM cement, MTA, or saline (control) in petri dishes for 30 days. Finally, dentin samples were subjected to a three-point bending test after the intervention, and the flexural strength data were analyzed using one-way ANOVA, Tukey’s test, and t test.

Thirty-day exposure to all four biomaterials decreased the flexural strength of root dentin (P<0.05). The four groups were significantly different in terms of the flexural strength of root dentin (P=0.001). The flexural strength of root dentin was significantly lower following exposure to calcium hydroxide (P=0.003), Biodentine (P=0.011), CEM cement (P=0.001), and MTA (P=0.007) compared to saline. The reduction in strength following exposure to calcium hydroxide was higher than that in Biodentine, CEM cement, and MTA groups (P<0.05) while the latter three were not significantly different in this respect (P>0.05).

In general, all four tested biomaterials decrease the dentin strength although this reduction is more prominent by calcium hydroxide.

Stylohyoid ligament ossification is a complication that is repeatedly and accidentally observed on panoramic radiographs and may be the cause of some symptoms. Accordingly, awareness of this incidence enables the clinicians in the accurate diagnosis of head and neck pains while avoiding unneeded therapy.

This was a descriptive cross-sectional study. The number of samples was 196 people who referred to an oral and maxillofacial radiology center in Ilam in 2020. Information was completed by a checklist which consisted of two parts, including a questionnaire (age, gender, history of maxillofacial trauma, history of maxillofacial surgery, and pregnancy) and a second part (including the ossification of the stylohyoid complex, its length, involved side, and the process category according to Langlais classification). Differences between the groups were compared by Student’s t test, Welch’s t test, or chi-square test (P<0.05).

The results revealed the influence of age on the calcification and elongation patterns of the styloid process while no significant association was found between gender and elongation and calcification patterns. The ossification of the stylohyoid complex was unilateral and bilateral in 24 (40.6%) and 35(59.3%) patients. Finally, the ossification of the stylohyoid complex was bilateral in 17 patients (48.6%) aged 40-59 years.

The evaluation of stylohyoid complex patterns using panoramic radiography is essential, especially in patients with related symptoms. Further studies are needed to completely understand the underlying mechanism of the ossification of the styloid process and to assess different types of the styloid process and the relation between them in patients.

Statins are effective therapeutic agents for the treatment of cardiovascular diseases. Their favorable effects on various aspects of oral health including promising effects on bone metabolism and pleiotropic impacts such as anti-inflammatory properties made these drugs a current area of interest in the field of orthodontics. Therefore, the aim of this study was to evaluate the effects of statins on orthodontic tooth movement (OTM) in animals undergoing orthodontic treatments.

Several databases were comprehensively searched for studies measuring the effects of statins on the OTM up to January 2020, including MEDLINE, ISI Web of Science, EMBASE, Scopus, and Cochrane. Animal studies evaluating the effects of statins on tooth movements in animals undergoing orthodontic treatments were selected based on the PICO model .Study selection, data extraction, risk of bias, and study quality assessment were independently performed by two reviewers. Finally, the data were analyzed using random-effects meta-analysis and the mean difference (MD) was used for comparing the outcome measures.

Three randomized trials were finally included in this meta-analysis. According to the Systematic Review Centre for Laboratory animal Experimentation Tool, all the included studies had at least one domain at a high risk of bias. The amount of the OTM was insignificantly lower in the statin group (MD = 0.134 mm, %95 confidence interval = -0.020-0.288, P>0.05).

Due to the low quality and methodological inconsistencies among the included studies, conclusive confirmation regarding the effect of statins on the OTM remains debatable.

Peripheral giant cell granuloma (PGCG) or the so-called giant cell epulis is the most common oral giant cell lesion. It normally appears as a soft tissue purple-red nodule. This lesion is certainly not a true neoplasm, but in nature, it may be reactive, thought to be stimulated by local irritation or trauma. Nonetheless, the exact cause is definitely not understood well. In appearance, lesions vary from smooth, uniformly outlined masses to irregularly developed, multilobed surface indentation protuberances. Margin ulcerations are occasionally observed as well. The lesions are painless, differ in size, and can cover many teeth. It may be a lesion on the gingiva or alveolar crest that is sessile or pedunculated, common with respect to the molars and incisors and occurs in reaction to the local response.