Self-assembling multiblock amphiphiles: Molecular design, supramolecular structure, and mechanical properties

We perform off-lattice, canonical ensemble molecular dynamics simulations of the self-assembly of long segmented copolymers consisting of alternating, tunably attractive and hydrophobic {\em binder} domains, connected by hydrophilic {\em linker} chains whose length may be separately controlled. In such systems, the molecular design of the molecule directly determines the balance between energetic and entropic tendencies. We determine the structural phase diagram of this system, which shows collapsed states (dominated by the attractive linkers' energies), swollen states (dominated by the random coil linkers' entropies) as well as intermediate network hydrogel phases, where the long molecules exhibit partial collapse to a {\em single molecule network} state. We present an analysis of the connectivity and spatial structure of this network phase, and relate its basic topology to mechanical properties, using a modified rubber elasticity model. The mechanical properties are further characterized in a direct computational implementation of oscillatory rheology measurements. We find that it is possible to optimize the mechanical performance by an appropriate choice of molecular design, which may point the way to novel synthetics that make optimal mechanical use of constituent polymers

A Rare Presentation of Distomolar Teeth: Report of a Case

Objectives A distomolar tooth, also known as a distodens, is a supernumerary tooth located distally to the third molars. It is an uncommon phenomenon with a reported prevalence of 0.02% to 0.16% across various countries. Distomolars can manifest as singular or multiple, erupted or impacted, and can occur unilaterally or bilaterally. To the best of our knowledge, very few cases of three distomolars in one patient have been reported in the English literature. Case This study presents the case of a healthy 22-year-old male who was found to have three impacted distomolars. These distomolars were located bilaterally in the maxilla and unilaterally on the left side of the mandible. They were discovered incidentally during a routine radiographic examination. As the patient expressed no discomfort or complaints related to this condition, no treatment was administered. Instead, the patient was placed on a regular follow-up. Conclusion Although the occurrence of distomolars is rare, clinicians should regard it as a potential risk factor for the development of intraosseous lesions, which are often associated with an impacted tooth

The Effectiveness of Aromatherapy in the Management of Labor Pain and Anxiety: A Systematic Review

BACKGROUND: Aromatherapy as an alternative and complementary medicine is a well-known method for reducing the symptoms of various physiological processes such as labor experience. The aim of this study was to systematically review the currently available evidences evaluating the use of aromatherapy for management of labor pain and anxiety.METHODS: In a systematic review, 5 databases (PubMed, SCOPUS, Web of Science, Google Scholar and Scientific Information Database [SID]) were searched, from database inception up to December 2019. Keywords used included (aromatherapy OR "“essential oil” OR "aroma*") AND (pain OR anxiety) AND (labor OR delivery). Using the Cochrane Collaboration's 'Risk of bias' method; the risk of bias in the included studies was evaluated.RESULTS: A total of 33 studies were verified to meet our inclusion criteria. Most of the included studies were conducted in Iran. Aromatherapy was applied using inhalation, massage, footbath, birthing pool, acupressure, and compress. The most popularly used essential oil in the studies was lavender (13 studies), either as a single essential oil or in a combination with other essential oils. Most of included studies confirmed the positive effect of aromatherapy in reducing labor pain and anxiety.CONCLUSION: The evidences from this study suggest that aromatherapy, as a complementary and alternative modality, can help in relieving maternal anxiety and pain during labor.&nbsp

The largest bilateral gemination of permanent maxillary central incisors: report of a case

Gemination is defined as an attempt to make two teeth from one enamel organ. Bilateral presentation of this phenomenon is very rare, with prevalence of 0.01% to 0.04% in the primary, and 0.05% in the permanent dentition. This paper describes a rare case of huge bilateral gemination of permanent maxillary central incisors in a nine-yearold Iranian boy with poor aesthetic. The patient did not have history of anomaly in his primary dentition and in his family either. This type of dental anomaly can cause clinical problems in the form of malocclusion, poor aesthetic, and impaction of adjacent teeth, caries, and periodontal destruction

Oral Manifestations of Coronavirus Disease-19: A Mini-review

BACKGROUND: Recently, outbreak of novel coronavirus (CoV) (severe acute respiratory syndrome-CoV-2 [SARS-CoV-2]) has been emerged as a serious public health concern. On February 11, 2020, the WHO announced an official name for this disease, CoV disease-(COVID)-19. The virus can cause systemic complications such as lung involvement, skin, and oral complications. AIM: The aim of this study was to review of the oral manifestations of COVID-19. METHODS: In this narrative review study, we searched all articles between 2010 and 2020 in PubMed, Scopus, Science Direct related to COVID-19, and its oral manifestations, using the following terms: “Coronavirus,” “COVID-19,” and “SARS-CoV-2” in combination with “Stomatognathic diseases,” “Oral manifestation,” and “Mouth diseases.” RESULTS: The most common oral manifestations in people with COVID-19 that we get after searching are: salivary gland disease, xerostomia, taste and smell alterations, and oral mucosal lesions. CONCLUSIONS: Since almost all of the oral findings appear at the asymptomatic phase of disease, identification of these symptoms can help to timely diagnosis of the main disease

Tongue squamous cell carcinoma in a patient with systemic sclerosis: A case report

Objective: Systemic sclerosis (SS) is a chronic autoimmune disease of connective tissue, which involves skin and internal organs, and results in collagen deposition and fibroblasts activation. Studies have reported a higher risk of malignancy in patients with progressive systemic sclerosis (PSS).The aim of this study is to report a case of tongue squamous cell carcinoma (SCC) in a patient with PSS.Case: A 46-year-old woman with SS presented to the Department of Oral Medicine of Shahid Beheshti University of Medical Sciences Dental School with chief complaint of an ulcer on her tongue. During intraoral examination, an asymptomatic ulcer measuring 2.0×1.5 cm was discovered on the right lateral border of the tongue. Incisional biopsy under local anesthesia was performed and histopathological report confirmed presence of squamous cell carcinoma. After further evaluation, surgery was performed, followed by three sessions of brachytherapy and six sessions of chemotherapy. After 26 months of follow-up, there was no evidence of recurrence.Conclusion: Periodic screening examinations are necessary to discover possible malignancies in primary stages in patients with SS

Morphological patterns of lip prints in an Iranian population

Lip prints are verified to be unique to an individual and stable over time; hence they have potential for human identification purposes. The aim of this study was to assess the individuality and variability of lip prints in an Iranian population for the first time. We also sought to assess the possibility of sex determination via lip printing. Lip prints of 96 individuals including 22 males and 74 females were recorded on a plain white paper using a dark-colored lipstick and 50 mm of Scotch tape. Each lip print was divided into six sextants and studied independently by two observers using a magnifying lens to examine the lip grooves. The Suzuki and Tsuchihashi’s classification was used to define the lip patterns and the data were statistically analyzed. In the present study, no identically similar lip prints were observed. Type V was the most predominant pattern recorded in the study sample (33.16%), followed by type I (24.13%), type II (18.75%), type IV (11.63%), type I’ (9.72%) and type III (2.60%). In addition, no statistically significant difference was observed in the lip print patterns of males and females. It can be concluded that lip prints are unique and their analysis may enable human identification

Diagnosis of simulated condylar bone defects using panoramic radiography, spiral tomography and cone-beam computed tomography: a comparison study

Objectives: Radiographic examination is one of the most important parts of the clinical assessment routine for temporomandibular disorders. The aim of this study was to compare the diagnostic accuracy of cone-beam computed tomography(CBCT) with panoramic radiography and spiral computed tomography for the detection of the simulated mandibular condyle bone lesions. Study Design: The sample consisted of 10 TMJs from 5 dried human skulls. Simulated erosive and osteophytic lesions were created in 3 different sizes using round diamond bur and bone chips, respectively. Panoramic radiography, spiral tomography and cone-beam computed tomography were used in defect detection. Data were statistically analyzed with the Mann-Whitney test. The reliability and degrees of agreement between two observers were also determined by the mean of Cohen's Kappa analysis. Results: CBCT had a statistically significant superiority than other studied techniques in detection of both erosive and osteophytic lesions with different sizes. There were significant differences between tomography and panoramic in correct detection of both erosive and osteophytic lesions with 1mm and 1.5 mm in size. However, there were no significant differences between Tomography and Panoramic in correct detection of both erosive and osteophytic lesions with 0.5 mm in size. Conclusions: CBCT images provide a greater diagnostic accuracy than spiral tomography and panoramic radiography in the detection of condylar bone erosions and osteophytes

Oral Hard Tissue Lesions: A Radiographic Diagnostic Decision Tree

BACKGROUND: Focusing on history taking and an analytical approach to patient’s radiographs, help to narrow the differential diagnoses. AIM: This narrative review article aimed to introduce an updated radiographical diagnostic decision tree for oral hard tissue lesions according to their radiographic features. METHODS: General search engines and specialized databases including PubMed, PubMed Central, Scopus, Embase, EBSCO, ScienceDirect, and authenticated textbooks were used to find relevant topics by means of MeSH keywords such as “jaw diseases,” “maxilla,” “mandible,” “radiolucent,” “radiopaque,” “odontogenic,” “nonodontogenic,” “cysts,” and “tumors.” Related English-language articles published from 1973 to 2020, including reviews, meta-analyses, and original papers (randomized or non-randomized clinical trials; prospective; or retrospective cohort studies), case reports, and case series about oral hard tissue lesions were appraised. RESULTS: In this regard, bony lesions have been classified according to their radiographic pattern (radiolucent, mixed, radiopaque, and rarified), position (periapical, pericoronal and interradicular), margins (well and ill-defined), relation to dentition (with and without dental association), and number (solitary and multiple). In total, 50 entities were organized in the form of a decision tree. CONCLUSION: In this paper, an updated decision tree was proposed to help dental practitioners to make more accurate diagnoses and better treatment plans on the basis of radiographic characteristics

Oral contraceptive use and salivary C-erbB-2, CEA and CA15-3 in healthy women : a case-control study

Objectives: Oral contraceptives (OCP) are highly effective, safe and widely used. Higher exposure to endogenous and exogenous estrogens is generally thought to increase the risk of breast cancer. Therefore, this study was conducted to determine if oral contraceptive use affected the expression of CA 15-3, CEA and C-erb B-2 in the saliva of healthy women. Study design: The participants consisted of 87 healthy women (43 controls and 44 using oral contraceptives) ranging in age from 20 to 54 years. The volunteers participated by giving one ? time stimulated whole saliva samples. Then the samples were analysed for CA 15-3, CEA and C-erb B-2 concentrations. Results: The student t-test was used to compare group means for variables with comparable variability. The mean of C-erb B-2, CEA, and CA 15-3 concentrations (in the case and control groups) was (1.93, 1.70), (34.46, 31.62) and (12.58, 16.19) respectively. These differences were not statistically significant. Conclusions: Our findings suggest that the levels of the cancer biomarkers C-erb B-2, CEA and CA 15-3 were not affected by increased levels of estrogens in the body