The world is in the midst of a huge fundamental shift in fibre supply, demand balances, and policy changes. Governments around the world are introducing policy changes which influence the supply demand balance as the politicians' thoughts are uttered. Government agencies and their bureaucrats are imposing changes on industry even before the legislation is passed by the government in question.
This hoc change process will continue for a time to come until the countries in question show a tough-mindedness with regard to their land use policies. Policies affecting forest areas such as protection areas, Native land claims, the protection of biodiversity and a true goal of sustainable development ; which addresses the combined issues of cultural, environmental, social and economic matters.
Eventually all of these difficult issues will reach essential closure. Then there will be great new opportunities for investment to meet the growing demand for forest products ; leading to a strengthening competitive position in the more traditional producing areas such as Canada.

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To determine the position of the anteriorly displaced articular disc, we examined temporomandibular joints by magnetic resonance imaging (MRI) in 54 patients with unilateral temporomandibular joint dysfunction. MRI was done before conservative therapy in the occlusal and maximal open-mouth position. We drew a straight line connecting the lowest point of the articular eminence (point A) and the highest point of the external acoustic pore (point ) by tracing the sagittal view on MRI. On the standard A- line, points ', C', and D' were sought by dropping perpendicular lines from the deepest point of the glenoid fossa (point ), the highest point of the condylar head (point C), and the most posterior point of the articular disc (point D). We then determined the sagittal position of the articular disc in the glenoid fossa by measuring the distances ' and C'D' and sought the correlation between these distances and clinical findings. The results were as follows. 1. The distance ' in 33 patients with MRI-defined irreversible displacement of the disc was shorter than that in 10 patients with reversible displacement (.7±1.mm vs .±2.0mm, p<0.0001). In contrast, the distance C'D' in the former was longer than that in the latter (.0±1.7mm vs .±1.mm, P<0.0001). Of 29 discs displaced anteriorly less than mm in distance C'D', 19 (66%) had reversible or no displacement. However, 23 (92%) of 25 discs displaced more than mm in distance C'D' had irreversible displacement. 2. Disc deformity and abnormal signal intensity bands in the condylar head closely correlated with distances ' and C'D'. In 17 patients without disc deformity, mean ' and C'D' distances were .± 2.7mm and 0.2± 2.mm, respectively. In 19 and 18 patients with mild to moderate and severe deformity, the mean '(C'D') distances were .±1.mm (.±1.mm) and 2.7±1.mm (.±1.mm), respectively. . Although distance ' and C'D' did not correlate with clinical symptoms, the degree of anterior disc displacement correlated with the therapeutic effect of conservative therapy. The mean ' distance (7.±.7mm) in 15 patients with a complete response to conservative therapy was longer than that (.±1.mm) in patients with no improvement. These results indicate that the sagittal position of the articular disc can be determined by MRI and that successful conservative therapy is unlikely if anterior disc displacement extends beyond mm from the top of the condylar head, often resulting in irreversible displacement.

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