Reconsideration of pathogenesis and pathological classification of human caries pulpitis to apical periodontitis

In this year，unmyelinated nerve fibers in human caries pulpitis were cheifly studied.Pathogenesis and pathological classification of human caries pulpitis were also reconsidered on the base of results of a last and this year.Materials and Methods：Samples were 15caries teeth with acute severe symptoms.All teeth were upper or lower3rd molars。After bisection of teeth crowns the pulpal tissue which underlying the caries lesion were，were immediately removed and fixed in2%glutaraldehyde·2%paraformaldehyde solution。Ultrastructural observation were same manner as a last year.Results：10/15 teeth were identified with the suppurative inflammation。In foci of inflammatory cell infiltration，mainly neutrophils，bundles of unmyelinated nerve fibers irregularly waved，and sometimes showed small spiral masses.On the other hand.5/15 teeth were identified with fibrosis and tubercular proliferation of unmyelinated nerve fibers，so-called traumatic neuroma-like lesion without inflammatory c…More ell infiltration。Electron microscopically，unmyelinated nerves in the suppurative foci were almost surrounded by collagen fibrils，and no degenerative change of axons and schwann cells was found.In areas of loss of perinervous collagen fibrils，however，some vacuoles and/or dilation of axons was observed，nevertheless the basel lamina of schwann cells was intact.In so-called traumatic neuroma-like lesions，Schwann cells apparently showed reticular arrangements，and axons were involved in their arrangements.Summary：Our findings have allowed the hypothesis that inflammatory process of human caries pulpitis is modified by the chronic stimulation of the dental caries，and pathogenesis of human caries pulpitis differs essentially from the pulpitis caused by chemys.Unmyelinated nerve of inflammatory foci may play a role in the intensive acute clinical symptoms of caries pulpitis.Finaly，pathological classification of human caries pulpitis may be summarized as follows：1.early lesion，2.suppurative lesion，3.granulomatous lesion，4.necrosis or gangrene of the dental pulp.Less：Less

In this year, unmyelinated nerve fibers in human caries pulpitis were cheifly studied. Pathogenesis and pathological classification of human caries pulpitis were also reconsidered on the base of results of a last and this year.Materials and Methods:Samples were 15 caries teeth with acute severe symptoms. All teeth were upper or lower 3rd molars. After bisection of teeth crowns the pulpal tissue which underlying the caries lesion were, were immediately removed and fixed in 2% glutaraldehyde ・ 2% paraformaldehyde solution. Ultrastructural observation were same manner as a last year.Results:10/15 teeth were identified with the suppurative inflammation. In foci of inflammatory cell infiltration, mainly neutrophils, bundles of unmyelinated nerve fibers irregularly waved, and sometimes showed small spiral masses. On the other hand. 5/15 teeth were identified with fibrosis and tubercular proliferation of unmyelinated nerve fibers, so-called traumatic neuroma-like lesion without inflammatory c … More ell infiltration. Electron microscopically, unmyelinated nerves in the suppurative foci were almost surrounded by collagen fibrils, and no degenerative change of axons and schwann cells was found. In areas of loss of perinervous collagen fibrils, however, some vacuoles and/or dilation of axons was observed, nevertheless the basel lamina of schwann cells was intact. In so-called traumatic neuroma-like lesions, Schwann cells apparently showed reticular arrangements, and axons were involved in their arrangements.Summary:Our findings have allowed the hypothesis that inflammatory process of human caries pulpitis is modified by the chronic stimulation of the dental caries, and pathogenesis of human caries pulpitis differs essentially from the pulpitis caused by chemical of physical effects. Unmyelinated nerve of inflammatory foci may play a role in the intensive acute clinical symptoms of caries pulpitis. Finaly, pathological classification of human caries pulpitis may be summarized as follows: 1. early lesion, 2. suppurative lesion, 3. granulomatous lesion, 4. necrosis or gangrene of the dental pulp. Less