1. We investigated the contribution of skin strain-related sensory inputs to movement perception and execution in five normal volunteers. The dorsal and palmar skin of the middle phalanx and the proximal interphalangeal (PIP) joint were manipulated to generate specific strain patterns in the proximal part of the index finger. To mask sensations directly related to this manipulation, skin and deeper tissues were blocked distal to the mid-portion of the proximal phalanx of the index finger by local anaesthesia. 2. Subjects were asked to move their normal right index finger either to mimic any perceived movements of the anaesthetized finger or to touch the tip of the insentient finger. 3. All subjects readily reproduced actual movements induced by the experimenter at the anaesthetized PIP joint. However, all subjects also generated flexion movements when the experimenter did not induce actual movement but produced deformations in the sentient proximal skin that were similar to those observed during actual PIP joint flexion. Likewise, the subjects indicated extension movement at the PIP joint when strain patterns corresponding to extension movements were induced. 4. In contrast, when the skin strain in the proximal part of the index finger was damped by a ring applied just proximal to the PIP joint within the anaesthetized skin area, both tested subjects failed to perceive PIP movements that actually took place. 5. It is concluded that (i) the brain's assessment of the position at finger joints may be determined by afferent signals generated as a result of movement-associated skin strain patterns, (ii) afferent signals originating in skin mechanoreceptors under certain circumstances have precedence over signals generated in mechanoreceptive muscle afferents with respect to the perception of movements and the control of motor behaviour, and (iii) skin strain may be perceived as joint movements rather than skin deformation.

Although pre-fabricated carbon fibre posts have been used during the past decade clinical evaluations of the technique are still few. Using dental records and radiographs the clinical performance of 65 pre-fabricated carbon fibre posts (Composipost and Endopost) placed in 48 patients who regularly visited a general practice were evaluated in the present study. After an average time of 2.3 +/- 0.8 years (median 2.1 years, range 1-4.9 years) of clinical service the failure rate was 3%. Failure occurred in one tooth with a single crown restoration and in one tooth that was part of a cantilever fixed partial denture. Although the failure rate is lower than those mostly reported for metallic posts and cores more clinical studies are necessary to assess the suitability of pre-fabricated carbon fibre posts for routine use as an alternative to individually cast posts.

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