Adrenergic vessel innervation in the rat incisor pulp

abstract – The presence of adrenergic axons and nerve terminals has been demonstrated in the rat incisor pulp by means of the histochemical fluorescence method of H illarp & F alck . Adrenergic, nerve terminals in close connection with blood vessel walls were observed at all levels in this tissue, although there was an excess in the apical region. Administration of a MAO-inhibitor and noradrenaline increased the fluorescence intensity markedly, while reserpine and sympathectomy could abolish the fluorescence. The findings suggest the presence of an adrenergic regulation of blood flow in the rat incisor pulp and consequently an indirect nervous influence on the dentinogenesis. The possible relation between a suggested circadian rhythm in the activity of peripheral adrenergic neurons and the incremental pattern of the dentin is discussed.     

Effect of nutritional hyperparathyroidism on experimental periodontitis in the dog

abstract – The purpose of the present investigation was to induce osteopenia of the alveolar process by feeding dogs a calcium-deficient, phosphorus-rich diet, and to determine whether dogs suffering from nutritional secondary hyperparathyroidism (NSH) developed: (1) increased tooth mobility, (2) gingivitis and (3) periodontitis with marginal alveolar bone resorption in plaque-free areas and in areas where plaque and calculus were allowed to accumulate. The experiments were performed on six, 12-month-old Beagle dogs. During an experimental period of 18 months, four dogs (test group) were fed a low calcium, high phosphorus diet of a soft consistency. The controls were fed an adequate but soft diet. The teeth of the right jaws were regularly subjected to thorough cleaning. NSH and osteopenia of the alveolar bone were induced in the test dogs. Osteopenia, however, did not result in an increased tooth mobility or gingivitis in the absence of plaque. In areas where dental deposits were allowed to accumulate, pathologic pockets gradually developed in both test and control animals, but the degree of attachment loss was the same in both groups.     

Late symptoms after pregnancy-related deep vein thrombosis

Summary. Thromboembolism during pregnancy is a rare complication with a potential fatal outcome. Very little is known about long-term effects and therefore 104 women with thrombosis during pregnancy or puerperium were identified and their subjective complaints were assessed in a questionnaire. All had their thrombosis diagnosed by objective methods and the median follow-up time was 11 years. In spite of anticoagulant treatment only 22% were without complaints; 4% had ulceration, all occurring in the group with thrombosis during pregnancy. Significantly more women who had had their thrombosis during pregnancy used compression bandages than those who had their thrombosis during puerperium. The severity of the symptoms increased with the increasing number of thromboses. Anticoagulant therapy of the acute episode does not appear to alter the degree of long-term handicap in the lower limbs.     

The Epidemiology of Pacemaker Implantations in Fyn County, Denmark

Throughout the last three decades the number of patients with pacemakers has increased. Registers of pacemakers and pacemaker patients have been established to monitor, for example, the battery life expectancy and patient data. We have analyzed the registry for Fyn county, Denmark, which includes data on incidence, prevalence, and mortality rates among patients with pacemakers during the period from 1964 to 1990. The analyses show that the prevalence rate is steadily increasing as a result of a combination of an increasing incidence rate and a stable mortality rate among the pacemaker patients. Based on the development in the first almost 30 years of pacemaker implantations, two trends of the future prevalence of pacemaker patients are projected. Provided constant mortality rates and expected incidence rates of 300 per million person years and 350 per million person years, respectively, the prevalence will reach a plateau of 2.7 per 1,000 persons and 3.1 per 1,000 persons, respectively, within the next 25 years.     

Clinical and scanning electron microscopic study of surface changes of incipient caries lesions after debonding

Abstract — The surface features of incipient caries lesions around bonded orthodontic brackets were assessed longitudinally. In standardized periods after debonding and clean-up, color slides were made and silicone impressions were taken of two maxillary incisors on each of six adolescent patients. These teeth were characterized by varying degrees, of macroscopically visible demineralized white areas around the bonded brackets. The color slides were studied in a dark room. The positive surface replicas were studied in SEM. At the time of debonding heavy accumulations of dental plaque were observed in all areas corresponding to the white, demineralized areas. During the experimental period there was a reduction in these plaque deposits. The appearance of the lesions changed from chalky-white at the time of debonding to a more diffuse opacity, particularly in the peripheral parts of the lesion. Examination of the surface replicas in the SEM revealed a general tendency toward leveling of the surface of the lesion indicating a loss of porous tissue. At higher magnification the lesions showed signs of wear. Four teeth were presented to illustrate typical examples of the time-related changes at the surface. The present study confirmed that removal of cariogenic challenge results in arrest of further dermineralization. The gradual regression of the lesion at the clinical level was believed to be primarily a result of surface abrasion with some redeposition of minerals.     

Dental care habits and knowledge of oral health in insulin-dependent diabetics

Abstract – The aim of this study was to investigate dental care habits and knowledge of oral health in age- and sex-matched adult long and short duration insulin-dependent diabetics and non-diabetics. Ninety-four long and 86 short duration diabetics and 86 non-diabetics, aged 20–70 years, participated in the study. All subjects answered a questionnaire with 38 questions about dental visits, attitudes to and knowledge of dental diseases, toothcleaning, dietary and smoking habits, and oral sensations. Among the diabetics there was a rather large group that did not visit a dentist annually. The diabetics also required more emergency dental care and were not as willing as the non-diabetics to spend time and money on their teeth. The compliance with dietary advice was poor among the diabetics. Oral discomfort such as prickling and burning sensations, metallic and bad taste was rare in both diabetics and non-diabetics. In the diabetics, however, a feeling of mouth dryness was common.     

Effects of halothane on mucociliary activity in vivo

The effect of halothane on mucociliary activity in the rabbit maxillary sinus in vivo was recorded photoelectrically. Administration of halothane (1%, 2% or 4%) into the maxillary sinus induced a temporary acceleration of mucociliary activity. The peak increase (39.1% ± 9.1%, p < 0.05, n = 5) was seen after the 4% concentration. Long-term exposure (60 minutes) of the maxillary sinus to halothane (2%) first induced an increase of 28.4% ± 4.6% (p < 0.05, n = 6), lasting approximately four minutes, and followed after about 15 minutes by a decrease of mucociliary activity. The maximum decrease during the 60-minute period was 19.6% ± 2.8% (p < 0.05, n = 6). Mucociliary activity returned to its baseline level approximately 25 minutes after withdrawal of halothane. Halothane delivered to the rabbit through a tracheal cannula at 1.1% for 60 minutes did not impair mucociliary activity in the maxillary sinus. On the contrary, it initially stimulated mucociliary activity, 19.9% ± 2.7% (p <0.05, n = 5). There was also an initial increase in respiratory rate from 62 ± 7.3 to 89 ± 12.9 breaths per minute (p < 0.05), which was noticeable after approximately 10 seconds and lasted 4 to 5 minutes. The dose-dependent increase in mucociliary activity seen after short-term exposure to halothane is probalby due to stimulation of afferent C fibers, because halothane may be considered an airway irritant. The reversible depressant effect seen after 15 minutes of exposure is in accordance with findings in previous studies in vitro. The mechanism by which halothane impairs mucociliary activity is at present not known. However, halothane administered to the lower airways does not impair mucociliary activity in the maxillary sinus, indicating that halothane affects the ciliated epithelium directly and that the state of anesthesia itself has no effect on mucociliary activity. (OTOLARYNGOL HEAD NECK SURG 1995;112:714-22.)     

SCREENING FOR CONGENITAL HYPOTHYROIDISM

ABSTRACT. Larsson, A., Ljunggren, J. G., Ekman, K., Nilsson, A. and Olin, P. (Departments of Paediatrics and Child Psychiatry, Karolinska Institute, St. Goran's Children's Hospital; the Department of Medicine, St. Göran's Hospital; and the PKU Section of the Department of Bacteriology, National Bacteriological Laboratory, Stockholm, Sweden). Screening for congenital hypothyroidism. I. Laboratory results of a pilot study based on dried blood samples collected for PKU screening. Acta Paediatr Scand, 70:141, 1981. – A pilot study was performed to establish optimal conditions for nation-wide screening for congenital hypothyroidism in Sweden. The levels of T₄ and TSH were determined by automated radioimmunoassay in the dried blood spots, routinely collected for PKU screening on the fifth postnatal day, from all 1979, 2 infants born in the Stockholm area during a 14-month period. To identify safe minimum recall criteria for routine use, infants were recalled if the TSH level was more than 30 mU/l of plasma or–if they were not preterm–the T₄ concentration was less than -2 S.D. of the mean. Altogether 160 infants were recalled. Seven newborns with congenital hypothyroidism were identified, 6 with primary and one with secondary hypothyroidism. Five infants had decreased levels of thyroxine-binding globulin. The results of the follow-up analyses from recalled infants showed that determination of the reverse-T₃ level may be of diagnostic value around the 23rd day of life. The results of the clinical investigation of recalled infants are reported in a subsequent paper and a programme for nation-wide screening for congenital hypothyroidism is proposed.