Aesthetic considerations in endodontics: internal bleaching

During endodontic treatment of any tooth, aesthetics must be considered in the same manner as during any other dental treatment. The most common aesthetic challenge associated with endodontics is the discoloration of natural tooth structure. The discoloration may be a result of pulp pathosis, especially pulpal hemorrhage prior to or during treatment, or it may be due to various endodontic and restorative materials placed in the pulp chamber. There are several simple measures that can be utilized during and following endodontic treatment to eliminate or reduce aesthetic deficiency. The learning objective of this article is to discuss internal bleaching of discolored pulpless teeth that have been endodontically treated. The discussion includes the chemical composition of bleaching agents and principles by which they function during the bleaching procedures.     

Use of formal and informal sources of mental health care among older African-American public-housing residents

BACKGROUND: Elderly residents of public housing have high rates of psychiatric disorders, but most of those in need of care do not use any mental health service. This study examines the use of formal and alternative informal sources of mental health care in a sample of elderly African-American public-housing residents. METHOD: Data from an epidemiological survey of six Baltimore public-housing developments for the elderly (weighted N = 818) were analysed to examine the utilization of mental health services by older African-American residents. Logistic regression analyses were used to determine correlates of using formal and informal sources by those needing mental health care. RESULTS: Thirty-five per cent of subjects needed mental health care. Less than half (47%) of those in need received any mental health care in the previous 6 months. Residents in need were more likely to use formal (38.5%) than informal sources (18.6%) for care. The strongest correlates of using formal providers were substance use disorder (OR = 15.62), Medicare insurance (OR = 10.31) and psychological distress (OR = 10.27). The strongest correlates of using informal sources were perceiving little or no support from religious/spiritual beliefs (OR = 21.65), cognitive disorder (OR = 19.71) and having a confidant (OR = 15.07). CONCLUSIONS: Contrary to elderly African-Americans in general, those in public housing rely more on formal than informal sources for mental health problems. Nevertheless, both sources fail to fill the gap between need and met need. Interventions to increase identification, referral and treatment of elderly public-housing residents in need should target general medical providers and clergy and include assertive outreach by mental health specialists.     

Stream biodiversity: the ghost of land use past

The influence of past land use on the present-day diversity of stream invertebrates and fish was investigated by comparing watersheds with different land-use history. Whole watershed land use in the 1950s was the best predictor of present-day diversity, whereas riparian land use and watershed land use in the 1990s were comparatively poor indicators. Our findings indicate that past land-use activity, particularly agriculture, may result in long-term modifications to and reductions in aquatic diversity, regardless of reforestation of riparian zones. Preservation of habitat fragments may not be sufficient to maintain natural diversity in streams, and maintenance of such biodiversity may require conservation of much or all of the watershed.     

Glucose transporters in rat peripheral nerve: paranodal expression of GLUT1 and GLUT3

Peripheral nerve depends on glucose oxidation to energize the repolarization of excitable axonal membranes following impulse conduction, hence requiring high-energy demands by the axon at the node of Ranvier. To enter the axon at this site, glucose must be transported from the endoneurial space across Schwann cell plasma membranes and the axolemma. Such transport is likely to be mediated by facilitative glucose transporters. Although immunohistochemical studies of peripheral nerves have detected high levels of the transporter GLUT1 in endoneurial capillaries and perineurium, localization of glucose transporters to Schwann cells or peripheral axons in vivo has not been documented. In this study, we demonstrate that the GLUT1 transporter is expressed in the plasma membrane and cytoplasm of myelinating Schwann cells around the nodes of Ranvier and in the Schmidt-Lanterman incisures, making them potential sites of transcellular glucose transport. No GLUT1 was detected in axonal membranes. GLUT3 mRNA was expressed only at low levels, but GLUT3 polypeptide was barely detected by immunocytochemistry or immunoblotting in peripheral nerve from young adult rats. However, in 13-month-old rats, GLUT3 polypeptide was present in myelinated fibers, endoneurial capillaries, and perineurium. In myelinated fibers, GLUT3 appeared to be preferentially expressed in the paranodal regions of Schwann cells and nodal axons, but was also present in the internodal aspects of these structures. The results of the present study suggest that both Schwann cell GLUT1 and axonal and Schwann cell GLUT3 are involved in the transport of glucose into the metabolically active regions of peripheral axons.     

Assessment and psychotherapeutic intervention for an HIV-infected preschool child

Pediatric acquired immunodeficiency syndrome (AIDS) is becoming more common. Moreover, human immunodeficiency virus (HIV) positive status in multiple family members is common and complicates disease management. Practitioners treating these children are often unaware of the effect of the virus on the child's psychological, cognitive, and emotional functioning. In addition, children with AIDS frequently come from families facing pressing social problems, including homelessness, poverty, and drug addiction. HIV-positive children thus confront such diverse issues as the deterioration of developmental skills, social ostracism, and the possibility of imminent death, placing them in a socioemotional crisis. This paper presents a comprehensive psychotherapeutic intervention for such children.     

A bioadhesive delivery system as an alternative to infiltration anesthesia

OBJECTIVE: The aim of this study was to determine the feasibility of a novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride as a viable alternative to infiltration anesthesia in dentistry. STUDY DESIGN: The study was carried out in three stages. First, the drug delivery system (DDS) was subjectively evaluated for adherence to the gingival mucosa and peak effect of anesthesia. In the second stage, a comparative subjective and objective evaluation of the DDS with a marketed topical gel preparation was carried out. Finally an open label, nonblinded clinical trial was carried out using the exodontia model. A total of 49 extractions were attempted in 41 patients. The effect of the following variables was investigated in the study: (1) jaw (maxillary and mandibular), (2) overall mobility, (3) position-notation of tooth (1, 2, 3, 4 ...). The positive extractions were statistically analyzed by the t test comparison of means of two independent variables. RESULTS: Subjective evaluation revealed that the DDS adheres to the gingiva within a minute and produces peak effect in 15 minutes. Comparative study revealed that the DDS produces greater depth of anesthesia than the marketed topical gel. Of 49 extractions attempted with the DDS, 40 were successful, giving an efficacy of 81.63%. CONCLUSION: The novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride exhibits potential as a feasible alternative to infiltration anesthesia in dentistry.