Micro-optical elements from optical-quality ZIF-62 hybrid glasses by hot imprinting.

Hybrid glasses derived from meltable metal-organic frameworks (MOFs) promise to combine the intriguing properties of MOFs with the universal processing ability of glasses. However, the shaping of hybrid glasses in their liquid state - in analogy to conventional glass processing - has been elusive thus far. Here, we present optical-quality glasses derived from the zeolitic imidazole framework ZIF-62 in the form of cm-scale objects. These allow for in-depth studies of optical transparency and refraction across the ultraviolet to near-infrared spectral range. Fundamental viscosity data are reported using a ball penetration technique, and subsequently employed to demonstrate the fabrication of micro-optical devices by thermal imprinting. Using 3D-printed fused silica templates, we show that concave as well as convex lens structures can be obtained at high precision by remelting the glass without trading-off on material quality. This enables multifunctional micro-optical devices combining the gas uptake and permeation ability of MOFs with the optical functionality of glass. As an example, we demonstrate the reversible change of optical refraction upon the incorporation of volatile guest molecules.

MUC4 and MMP7 in saliva and gingival crevicular fluid (GCF) in adolescents at West Bengal, India.

Mucin 4 (MUC4) and matrix metalloproteinase 7 (MMP7) have been reported to be associated with chronic periodontitis as seen in gingival tissue biopsies. Therefore, it is of interest to estimate the levels of MUC4 and MMP7 in saliva and gingival crevicular fluid (GCF) samples of periodontitis in adolescents patients at West Bengal, India. MUC4 levels were significantly lower in saliva and GCF from periodontitis patients compared to healthy controls. However, MMP7 levels were found to be significantly higher in saliva and GCF from periodontitis patients. Thus, MUC4 and MMP7 are biomarkers for periodontitis diagnosis and towards further consideration.

Comparative evaluation of three different rotary instrumentation systems for removal of gutta-percha from root canal during endodontic retreatment: An in vitro study.

CONTEXT: Endodontic retreatment is performed in teeth with endodontic failures. The main goal of retreatment is cleaning and shaping of the root canal with removal of old root filling material. Hand instruments and rotary instruments are mainly used for removing this filling material. AIM OF STUDY: To compare the relative efficacy of three rotary instrumentation systems for removal of gutta-percha from root canal during endodontic retreatment. OBJECTIVE OF STUDY: To find out which NiTi system is more efficacious in retreatment and to check out the efficacy of retreatment with and without use of solvent. MATERIALS AND METHODS: Sixty freshly extracted, single-rooted human mandibular premolars were instrumented with K-files, and each root canal was filled with gutta-percha and AH Plus (Dentsply Detrey, Konstanz, Germany) sealer using lateral compaction. Specimens were then divided into three experimental groups with twenty specimens each. Groups were then subdivided into ten specimens each. Groups were then retreated either with or without solvent. The removal of gutta-percha was performed using ProTaper retreatment files, Mtwo retreatment files, and R-Endo files after 2 weeks. The amount of root canal filling material remnant in the coronal, middle, and apical thirds was measured using stereomicroscope and computer image analysis program. STATISTICAL ANALYSIS USED: Data were evaluated statistically using analysis of variance. RESULTS: ProTaper group was found to have less remnant filling material as compared to the other groups in coronal and middle thirds, but a significant difference was observed between ProTaper and Mtwo and Mtwo and R-Endo in the nonsolvent groups (P < 0.05). Mtwo group demonstrated less amount of remaining filling material in the nonsolvent group. CONCLUSIONS: Both nickel-titanium systems and ProTaper and Mtwo retreatment file systems, were found to be effective in the removal of root canal filling material. However, complete removal of gutta-percha from root canals did not occur with any of the experimental groups.

The ironies of human mind: a case of Rett syndrome.

BACKGROUND: Rett Syndrome (RS) is a chromosome X-linked genetic neurological disorder characterized by developmental regression, particularly in relation to expressive language and use of the hands. It is also associated with profound mental retardation and almost exclusively affects females. CASE DETAILS: A four and a half year old girl reported to our dental OPD for a dental checkup. On complete examination, she was diagnosed to be suffering from Rett syndrome. Preventive therapies and proper oral hygiene instructions were explained to her mother. CONCLUSION: Early diagnosis of such disorders is extremely important along with treatment of patients' problems with love and care to prevent them from further pain and stress.

Self-inflicted herpetic whitlow.

A 25-year-old dental radiographer reported to the outpatient department with lesions at the lower and upper lips which had later spread to his finger. On the basis of the given history and clinical features, a diagnosis of primary herpetic infection on the mouth followed by secondary infection on the finger was made and the patient was advised systemic and topical antiviral therapy following which his lesions healed uneventfully.

Tissue engineering in endodontics: root canal revascularization.

Root canal revascularization attempts to make necrotic tooth alive by the use of certain simple clinical protocols. Earlier apexification was the treatment of choice for treating and preserving immature permanent teeth that have lost pulp vitality. This procedure promoted the formation of apical barrier to seal the root canal of immature teeth and nonvital filling materials contained within root canal space. However with the success of root canal revascularization to regenerate the pulp dentin complex of necrotic immature tooth has made us to rethink if apexification is at the beginning of its end. The objective of this review is to discuss the new concepts of tissue engineering in endodontics and the clinical steps of root canal revascularization.

Oral manifestations of lipoid proteinosis: A case report and literature review.

Lipoid proteinosis is an uncommon autosomal recessive metabolic disorder that presents in early life with hoarseness and pox-like acneiform scars involving the skin and mucous membranes. Previous studies have attributed the prevalence of lipoid proteinosis to consanguineous parents. This paper reports a classical case of lipoid proteinosis with oral manifestations but without a history of consanguinity.