Transfer of Guided Emergence Profile Developed Using Customized Provisional Implant Restoration and Cementation Using an Abutment Replica Technique: A Case Report.

The long-term success of dental implants depends not only upon implant osseointegration, but also on the surrounding soft tissue health and profile. An ideal emergence profile contributes to the aesthetics of an implant restoration. It maintains long-term implant health by preventing potential food accumulation and forming a barrier against bacterial ingress. This article describes a method for obtaining an impression of implants that will capture the custom guided peri-implant soft tissue contours accurately, thus contributing to a final restoration with favorable aesthetics. We also describe a technique for reducing excess cement in a cement retained implant crown, thereby contributing to the health of the peri-implant tissues.

A Retrospective Study of Correlation between Radiological and Intra-Operative Findings in FESS: A Case Series.

Introduction: The imaging of the paranasal sinuses has advanced from plain X-ray films to CT and MRI. This advancement in the radiological field helps to yield more accurate information and aids in arriving at a proper differential diagnosis, especially for rhinosinusitis. However, CT should be used cautiously among patients considering its effects due to radiation. Aim: This study aims to correlate the pre-operative radiological findings with the intraoperative functional endoscopic sinus surgery findings in a series of 100 cases. Materials and Methods: A retrospective case series was conducted among 100 cases who had complaints relating to nose and paranasal sinuses in a tertiary care hospital, Chengalpattu. Their symptoms, clinical examination, pre-operative radiological findings, and intra operative findings have been recorded. The collected data was analyzed for correlation and agreement between pre-operative radiological findings and intraoperative findings. Results: Almost all the CT revealed pathologies like polyps, mucosal thickening, and anatomical variations. However, intraoperatively, only 64.5% had mucosal thickening and 23.6% had polyps. Poor to acceptable correlation has been reported among patients with OMC obstruction, polyps, and mucosal thickening, respectively. Yet, no agreement was seen between pre-operative radiological and intraoperative findings. Conclusion: Endoscopy remains the most valuable test to diagnose, confirm the severity and manage sinus related diseases.

Reductive Deamination by Benzyne for Deoxy Sugar Synthesis Through a Domino Reaction.

Benzyne was developed as a reducing agent in the key step of converting amino sugars and ketoses into deoxy sugars, which occur widely in natural products. Many deoxy sugars exhibit antibiotic and anticancer activities, and furthermore, they play essential biological roles. By treatment with CS2 and then Ac2O, amino sugars and ketoses were converted into the corresponding 1,3-thiazolidine-2-thiones. In the key step, these intermediates were treated with 2-trimethylsilylphenyl triflate (2.0 equiv.) and CsF (3.0 equiv.) in MeCN at 25 °C to produce acyclic enol acetates in 60-63 % yields. Saponification of the enol acetates with NaOMe/MeOH followed by intramolecular cyclization afforded the target 2-deoxy sugars. The key step of the reductive deamination involved a domino 1,2-elimination/[3+2]-cycloaddition/retro [3+2]-ring-opening sequence. The generality of this new method was proven by the use of various substrates, including pentoses, hexoses, monosaccharides, disaccharides, aldoses, and ketoses.

Syntheses of Chroman-2-ones and α-Amino Acids through a Diastereoselective Domino Reaction.

Many 3-aminochroman-2-ones and ß,ß-diarylalanines exhibit significant biological activities. A new method was thus developed for the syntheses of these compounds with high efficiency and diastereoselectivity. First, treatment of various phenols with Erlenmeyer-Plochl (Z)-azlactones and AlCl3 in toluene produced the desired cis-3-aminochroman-2-ones in 65-90% yields under kinetic control. This coupling reaction involved a domino process of Friedel-Crafts alkylation, 1,4-AlCl3 shift, transesterification, and protodealumination in a "single-flask." The corresponding products, however, were not generated by replacement of AlCl3 with a protonic acid. Second, hydrolysis of the resultant 3-amino-4-arylchroman-2-ones by NaHCO3 in a mixture of THF and water gave α-(N-benzoyl)amino acids. Further deprotection of these isolated compounds by use of hydrochloric acid (12 N) in methanol afforded the desired free amino acids in 80-88% yields. Under these optimized conditions, epimerization did not occur at the α carbons of α-(N-benzoyl)- and free α-amino acids. These new findings provide a convenient way to generate 3,4-disubtituted chroman-2-ones and ß,ß-diarylalanine derivatives with very high stereoselectivity.