Preliminary Single-Center Canadian Experience of Human Normothermic Ex Vivo Liver Perfusion: Results of a Clinical Trial.

After extensive experimentation, outcomes of a first clinical normothermic machine perfusion (NMP) liver trial in the United Kingdom demonstrated feasibility and clear safety, with improved liver function compared with standard static cold storage (SCS). We present a preliminary single-center North American experience using identical NMP technology. Ten donor liver grafts were procured, four (40%) from donation after circulatory death (DCD), of which nine were transplanted. One liver did not proceed because of a technical failure with portal cannulation and was discarded. Transplanted NMP grafts were matched 1:3 with transplanted SCS livers. Median NMP was 11.5 h (range 3.3-22.5 h) with one DCD liver perfused for 22.5 h. All transplanted livers functioned, and serum transaminases, bilirubin, international normalized ratio, and lactate levels corrected in NMP recipients similarly to controls. Graft survival at 30 days (primary outcome) was not statistically different between groups on an intent-to-treat basis (p = 0.25). Intensive care and hospital stays were significantly more prolonged in the NMP group. This preliminary experience demonstrates feasibility as well as potential technical risks of NMP in a North American setting and highlights a need for larger, randomized studies.

Laboratory animal models in periodontology.

Animal models are needed to objectively evaluate the pathogenesis of human periodontal diseases and its various treatment modalities. Selection of the appropriate animal model depends on the similarity of the periodontium and the nature of the disease to that of humans. The more commonly used animal models for studying the pathogenesis of periodontal disease, use of implants and guided tissue regeneration have been dogs and nonhuman primates. Periodontal disease in rodents has not been found to be as closely related to the human varieties. Rats and hamsters are best suited for caries and calculus research. Ferrets may be a promising new model for studying periodontal disease and calculus formation. Variables unique to each animal species are manifested by a wide range of clinical and histopathological features. Different species have distinct diets, habits, life spans, tissue structures, host defense mechanisms and genetic traits. This article describes the diversity seen in animal models used to study microbiological, immunological, and clinical features of periodontal disease and its prevention and treatment.

Tetracycline and its analogues: a therapeutic paradigm in periodontal diseases.

This article discusses the use of tetracyclines in the clinical management of periodontal infections. A review of the drugs pharmacology, pharmacokinetics, and potential adverse effects shows that they are relatively safe if used in appropriate dosages and under controlled conditions. Current data suggest that the routine use of tetracyclines in conjunction with the treatment of periodontitis is unnecessary. However, their distinctive characteristics can be utilized in different delivery systems as an adjunctive aid to conventional treatment of juvenile and refractory forms of periodontitis.

Effect of treatment on cyclosporine- and nifedipine-induced gingival enlargement: clinical and histologic results.

The clinical and histologic responses to periodontal treatment of gingival enlargements, induced when cyclosporine and nifedipine were administered singly or in combination, were evaluated. A significant correlation was noted between plaque, gingivitis, and gingival overgrowth. Severity of enlargement appeared to be greater in patients on combined therapy. All treatment approaches such as scaling, root planning, gingivectomy, and periodontal flaps, and a combination of therapies, were effective in the management of gingival overgrowth up to 1 year after completion of treatment. Adjunctive use of chlorhexidine was found to be beneficial.

[Initial and mid-term results of coronary angioplasty in early post-infarction unstable angina]. / Résultats initiaux et à moyen terme de l'angioplastie coronaire dans l'angor instable précoce post-infarctus.

The aim of this study was to assess the immediate efficacy and the medium-term risks and results of percutaneous transluminal coronary angioplasty (PTCA) in early post-infarction unstable angina. Thirty-six patients were included for a series of 248 consecutive PTCA procedures performed between December 1985 and January 1989. The average age was 56 years (range 35 to 84 years). The initial infarct was anterior (N = 16), inferior (N = 15), lateral (N = 5), without a Q wave (N = 22), transmural (N = 14) and treated by thrombolysis in 42 p. 100 of cases. The interval between initial infarction and PTCA was 16 +/- 3 days. A primary success was obtained in 33 cases (92%). One patient died of electromechanical dissociation at the beginning of the procedure. Two infarcts occurred due to acute coronary occlusions. None of the patients required emergency coronary bypass surgery. The specific risk of PTCA in early post-infarction unstable angina is acute coronary occlusion. This complication was observed in 9 patients (25%) and it required immediate repeat PTCA, associated with thrombolytic therapy in four cases. Coronary occlusion was more common in patients with transmural infarcts than in those without Q-waves (43% vs 14%; p less than 0.01) and in patients treated initially by thrombolysis compared with those not treated by thrombolysis (40% vs 15%; p less than 0.05). No fatalities or reinfarctions occurred during follow-up (average 9 +/- 8 months, range 2 to 35 months). A good clinical result was maintained in 71 per cent of patients treated by PTCA alone. Seven repeat PTCA procedures and 3 coronary bypass operations were performed during follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Periodontal considerations for provisional restorations.

Provisional restorations can cause alterations of tooth form, surface continuity, and the relationship of the restored tooth to the adjacent and opposing teeth as well as the periodontal tissues. As the integrity of the periodontium is of mutual interest to both the periodontist and the restorative dentist, it is important that the potential damage caused by restorative procedures and materials be avoided. Ideally, the provisional restoration should be considered an acrylic progenitor of the final restoration in all aspects except the material from which it is fabricated, its longevity, and the nuances of color and translucency. It should not be replaced by the permanent restoration until all treatment objectives have been accomplished. In an integrated multidisciplinary approach to dental care, it is logical that periodontal treatment precede final restorative procedures. The establishment and maintenance of periodontal health is clearly predicated on an intact dentogingival unit and shallow sulcular dimensions that allow accessibility for removal of plaque. Provisional restorations, whether single or multiple, must conform to and complement the healthy gingival environment if periodontal health is to be sustained. Direct and frequent communication between the periodontist and restorative dentist is a prerequisite for predictable and satisfactory results.

Antimicrobial agents in the prevention and treatment of periodontal diseases.

It has been estimated that there are more than 400 diseases affecting the oral cavity. In terms of prevalence, however, the major public health problems are caries and periodontal disease. Although these two destructive entities are completely different in many respects, they share a common denominator: the initial lesions are brought about by an aggregate of bacteria known as plaque. This article discusses chemical control of plaque in the treatment of gingivitis and antimicrobial control of subgingival plaque in the treatment of periodontitis. The authors address the use of antibiotics in the treatment of localized juvenile periodontitis, the ideal properties of antiplaque agents, and adjunctive subgingival application of antimicrobial agents.