Root surface alterations following manual and mechanical scaling: A comparative study.

OBJECTIVES: The aim of this study was to investigate the morphological and surface roughness changes in dental root samples following periodontal scaling by hand curette, piezoelectric ultrasonic devices or a combination of these. METHODS: Twenty-four monoradicular teeth extracted as a result of periodontal disease were divided into 4 groups: Group A was treated by piezoelectric ultrasonic scaler Piezon® Master 400; Group P by piezoelectric ultrasonic scaler PiezoSmart® ; Group C using Gracey curette 7/8; Group AC by a combined technique of piezoelectric ultrasonic scaler Piezon® Master 400 and Gracey curette 7/8. The treated samples were then analysed using a white light interferometer and scanning electron microscopy (SEM). RESULTS: Roughness analysis revealed major surface alterations in Group C (Sa  = 24.98 µm); the samples treated using the combined technique (Group AC) showed reduced but still significant alteration (Sa  = 14.48 µm), while samples treated with the piezoelectric ultrasonic devices (Group A and Group P) presented the lowest roughness values (Sa  = 8.99 and Sa  = 4.45 µm, respectively). A significant difference was found between groups C and P (P = 0.036). SEM analysis confirmed the roughness analysis revealing non-homogeneous surfaces in Group C, while a less morphological alteration was noted in the other groups. CONCLUSION: All periodontal devices used in this in vitro study produced a certain degree of surface alteration. Hand curettes appear to have a major impact on surface integrity compared with piezoelectric ultrasonic devices.

[Passive gymnastics]. / La ginnastica passiva.

There is at the moment a continuous proliferation of gymnasium centres, among which the so-called "Centres of passive or activated gymnastic" have recently assumed a particular importance. The Swedish Doctor Zander, in the XIX century, was a promoter of this kind of gymnastics, utilizing instruments invented by him. These instruments were able to perform fundamental movements without needing the active participation of the person involved. Today's machinery for passive gymnastics no longer have the therapy or rehabilitation as their main purpose, but their present first purpose is more aesthetic than scientific. The ancient and modern machinery for passive gymnastics, is sometimes an imitation of the action of a massager.

[Relation between the blood potassium and blood glucose responses and electrocardiographic changes, specifically the T wave, during the oral glucose tolerance test]. / Rapporto fra tipo di risposta kaliemica e glicemica e modificazioni elettrocardiografiche, interessanti l'onda T, in corso di "test" di tolleranza al glucosio per via orale.

As previously showed by the Authors, serum K+ levels significantly decrease during OGTT. Moreover, two possible patterns were separated: a) monophasic decrease ("M" type curve) causing a mild but continuous down-slope, possibly physiologically more relevant, and b) polyphasic decrease ("O" type curve) causing a sharp down-slope followed by a rebound to normal K+ levels. In 10 of 12 M type subjects (83%) electrocardiographic changes were shown after OGTT, comparative to only 9 out of 16 O type subjects. The Authors believe this to be suggestive of a heavier impact of kaliemic changes on to myocardial function in M type curves. The hypothesis needs further analysis.