Palatal impression template for a fully edentulous arch during stage I implant placement

It is often desirable to insert a fixed provisional resin restoration at stage II surgery when the implants are uncovered. It satisfies the patient's esthetics, phonetics, and functional demands and helps create a good emergence profile for the healing gingival tissue. This article presents a procedure that enables the clinician to fabricate a full-arch maxillary provisional restoration for a fully edentulous patient, which can be delivered at second-stage surgery at the time of uncovering the implants.(J Prosthet Dent 1997;77:630-2.)     

Stimulated whole saliva components in children with Down syndrome

The authors report on the components of stimulated whole saliva from children with Down syndrome—including pH, flow rate, sialic acid and protein concentrations, and amylase and peroxidase activity. Saliva samples were collected from 35 children aged 6–10 years. Of the participants, 17 had Down syndrome and 18 did not. To stimulate saliva production, the children chewed a piece of parafilm for 10 minutes before the sample was collected. Soon after collecting the saliva sample, the authors measured pH using a portable pH-meter. Sialic acid levels were determined with a thiobarbituric acid assay. Protein content was determined with Folin's phenol reagent. Amylase was assayed and the authors measured the maltose produced by the breakdown of starch and peroxidase using ortho-dianisidine.
No statistically significant difference was observed in levels of sialic acid (free and total) between the two groups. Protein concentration was about 36% higher in the group with Down syndrome. However, the salivary flow rate, pH, and amylase and peroxidase activities were lower among the children with Down syndrome.     

A chemomechanical system for caries removal and glass ionomer cement to restore fixed partial denture abutments

When a fixed partial denture fails due to recurrent caries under the casting of the abutments, a remake process usually requires a great deal of cooperation, multiple lengthy appointments, and financial resources. Many patients with special needs may not have the cooperation, tolerance, and resources to support such treatment. This paper describes an alternative method that utilizes a chemomechanical system for caries removal followed by a conventional restorative material to treat those patients     

Quality Assurance for the Laboratory Aspects of Prosthodontic Treatment

Inconsistency in the product returned from the commercial dental laboratory led to the development of a formal quality assurance (QA) program at the University of Detroit Mercy School of Dentistry in 1994. The goal of the program was to improve the quality of prosthodontic laboratory submissions and the returned product, facilitate laboratory communications, and, ultimately, enhance the quality and timeliness of patient care. Each student submission is evaluated with a criterion-referenced evaluation form. Deficiencies are communicated to the student, and the corrected submission is then sent to the laboratory. Three-year remake data from the main clinic (QA site) and an extramural clinic (non-QA site) demonstrate the effectiveness of the program. The major benefits are more efficient, cost-effective patient care, as well as the provision of a model for the student to practice the skills needed for effective communication with the dental technician, upon graduation.     

A comparative histological study of non-porous and micro-porous (algae-derived) hydroxylapatite ceramics

Two different types of hydroxylapatite ceramics were examined histologically to assess their effects on the healing of standardized bone defects drilled in the mandibular bone of beagles. After 40 days both materials were totally enclosed by newly-formed bone, but only the defects filled with micro-porous hydroxylapatite were found to show bone incorporation which is a good indicator of implant stability. These results suggest that the physio-chemical similarities between the micro-porous hydroxylapatite and native bone may promote effective bone incorporation which can increase the stability of implants.     

Does sodium nitroprusside reduce lung injury under cardiopulmonary bypass?

Objective: We hypothesized that direct pulmonary arterial infusion of sodium nitroprusside (SNP) would ameliorate lung injury under cardiopulmonary bypass. Methods: Experiments were performed on 12 adult mongrel dogs of both sexes weighing 20–28 kg. The animals were randomly divided into two groups of six animals each. All animals were subjected to total cardiopulmonary bypass (CPB) and moderate hypothermia (28°C core temperature). During total CPB, the aorta was clamped together with the pulmonary artery to prevent any antegrade flow to the lungs. After cardioplegic arrest for 120 min, the animals were rewarmed, weaned from CPB, and their condition stabilized for another 90 min. After the release of the aortic cross-clamp, the dogs received either a 5% glucose solution as a placebo (group I) or SNP (0.5 μg/kg per min) (group II), both infused into the pulmonary arterial line. The infusion was stopped after 60 min. To measure lung tissue malondialdehyde (MDA), water content and polymorphonuclear leukocytes count, lung tissue samples were taken before CPB and after weaning from CPB. In addition, alveolar-arterial oxygen difference (AaDO₂) for tissue oxygenation was calculated by obtaining arterial blood gas samples. Results: Values of MDA before CPB of 42.0±5.3 nmol/g of tissue rose to 67.6±5.7 nmol/g of tissue after weaning from CPB in group I (P=0.028). In group II MDA values also increased from 43.1±4.3 to 52.4±5.7 nmol MDA/g of tissue after weaning from CPB (P=0.046). The MDA increase in group II after CPB was found to be significantly lower than that for group I (P=0.004). The wet-to-dry lung weight ratio in the sodium nitroprusside group was 5.1±0.2, significantly lower than in the control group (6.8±0.4), (P=0.01). AaDO₂ increased significantly in group I (P=0.028). There was no statistically significant difference (P=0.065) between groups I and II. During histopathological examination it was observed that neutrophil counts in the lung parenchyma rose significantly after CPB in both groups. The increase in group I was significantly larger than that in group II (P<0.001). Conclusions: The results represented in our study indicate that pulmonary arterial infusion of sodium nitroprusside during reperfusion can reduce lung injury under cardiopulmonary bypass.