[Heat-induced symptomatology in human teeth. An in-vitro study]. / Sintomatologia indotta dal calore su denti umani. Studio in vivo.

OBJECTIVE: Various dental procedures can generate thermal increase in the dental pulp, in particular if they are incorrectly conducted. In literature the pulp cells are considered very heat sensitive. In this study the symptomatological response of patients during and after thermal administration to the dental crown has been recorded. The analysis of the symptomatology was used as an indication for the definition of the threshold of thermal damage. EXPERIMENTAL DESIGN: Twelve healthy teeth of four patients programmed for extraction were subdivided into six couples of homologous teeth. One tooth out of each couple was used for the immediate in vivo recording of the symptoms; the other, once extracted, was used to determine the thermal increase applied through the insertion of a thermocouple sensor. In each couple of teeth the thermal stimulus was equal. RESULTS: The average thermal increase was 11.2 degrees C. Pain starts at temperatures ranging from 39.5 to 50.4 degrees C with an average of 44.6 degrees C. This agrees with classical physiological data which reports the threshold of pain at 45 degrees C. CONCLUSIONS: The threshold of pain registered suggests that at temperatures below 44.6 degrees C damage to the dental pulp is improbable, at least in healthy teeth. The limit of 45 degrees C appears, therefore, to be a probable safe threshold, contrary to what is reported in literature.

[Echographic diagnosis of hip dysplasia in neonates. Reflections on two years' work at our ultrasonography center]. / Diagnosi ecografica nella displasia dell'anca nel neonato. Considerazioni su due anni di lavoro nel nostro centro di ecografia.

The paper evaluates the role of ultrasound examinations of the hip joint in neonates by comparing the results of a one-year screening study (non-selected group) with the findings in a selected group of neonates with a high risk of hip dysplasia. The introduction to the paper contains a general discussion of the clinical aspects of hip dysplasia and describes the main anatomical findings using echography.

[The differential threshold of thickness perception between antagonist teeth with different degrees of mouth opening]. / Soglia differenziale di percezione di spessori fra denti antagonisti a diversi gradi di apertura della bocca.

The discriminatory capacity of various widths, at different degrees of mouth opening, was assessed in a population of 22 individuals, 13 females and 9 males, with complete dentition. Seven series of nine widths each, based on central standardised measurements, and the choice of appropriate intervals enabled an univocal experimental method to be elaborated. The results showed that the differential threshold follows Weber's Law in a relatively linear fashion and that the perception interval varies in proportion from a tenth of a millimetre to 2 mm. In addition, whereas no specificity of direction was found for smaller widths, this was evident for larger widths but was contrary to that reported in earlier studies on the subject.

[The absolute threshold of the perception of thicknesses between antagonist teeth in contact]. / Soglia assoluta di percezione di spessori fra denti antagonisti a contatto.

An experimental technique has been evolved with the aim of identifying the perception threshold of widths between antagonist teeth using thin metal sheets of a known thickness either singly or as multiples. A reference sample was chosen from young subjects with integral dentition: 22 individuals, 13 women and 9 men, were included. Following statistical analysis, the results showed that, in spite of a wide individual variation, the absolute threshold may be located between 8 and 45 mu, with no difference between sexes. Contrary to published findings, no significant variation between back and front teeth was observed.