PGP9.5-immunoreactive nerve fibers in a deciduous second molar and succeeding permanent second molar in a 5-month-old cat (a).

<p>b-e: Higher magnification views of boxed areas in a. b: In the periodontal ligament under the resorbing root of deciduous second molar, PGP9.5-immunoreactive thick nerve fibers are detected as having a dot-like appearance. c: Many PGP9.5-immunoreactive nerve fibers are randomly distributed in the cervical area of the periodontal ligament of the permanent premolar. d: At the apical part of the distal side of the periodontal ligament of the distal root of the permanent second premolar, thick nerve fibers and thin varicose nerve fibers are running coronally. e: In the furcation area of the permanent premolar, PGP9.5-immunopositive thick nerve fibers (arrowheads) and thin nerve fibers with varicosity (arrows) are found. AB: alveolar bone, D1: dentin of primary teeth, D2: dentin in permanent teeth, P: pulp. Scale bars: 200 μm in a, and 50 μm in b, which is applicable to c-e.</p

PGP9.5-immunoreactivities in the periodontal ligament of the lower second deciduous molar of the 2-month-old cat.

<p>a; Low-powered image of the root apex. A few nerve fibers are found in the periodontal ligament (PDL). C; cementum, AB; alveolar bone. b; High-powered image of the boxed area in a. Thick nerve fibers run along the periodontal ligament. They are less ramified and do not terminate in the cementum. c-e: Double-labeling for PGP9.5 (c) and S100 (d), and merged image (e) in the periodontal ligament in a 2-month-old lower second deciduous molar. Rounded S100-positive cells (arrowheads in d, e) are associated with PGP9.5-immunoreactive nerve fibers. Scale bars: 100 μm in a, 50 μm in b, 20 μm in e (also applied for c and d)</p

Schematic drawing for quantitative analysis.

<p>The percentage of PGP 9.5 immunoreactive areas was measured in the cervical (C), middle (M) and apical (A) portions of distal side of distal root of deciduous second molar (m₂) of the 2-month-old cat and permanent second premolar (P₂) of the 5-month-old cat, and mesial side of mesial root of permanent first molar (M₁) of the 5- and 12-month-old cats at the length of 800 μm (dotted area).</p

PGP9.5 immunoreactivity in the periodontal ligament of the permanent premolar (a) and molar (b) in a 12-month-old cat.

<p>Many thick PGP9.5-immunoreactive thick nerve terminals are observed. They are less expanded. C: cementum Scale bars: 50 μm</p

Double-labeling images for PGP9.5 (a, d) and S100 (b) or S100β(e), and merged images (c, f) in the apical periodontal ligament of deciduous second molar of 2-month-old cat (2mo; a-c) and cervical portion of erupting permanent second premolar of 5-month-old cat (5mo; d-f).

<p>a-c: PGP 9.5-immunoreactive nerve fibers (a, c) accompanying S-100 immunoreactive structures (b, c) are observed without interruption in the ligament of 2-month-old-cat. d-f: PGP9.5-immunoreactive nerve fibers show a dot-like appearance (d, f), while continuity of S100 structures is recognized (e, f) in 5-month-old cat. Scale bar: 50 μm.</p

Radiographic images of the mandibles in 2-month-old (a), 5-month-old (b), and 12-month-old (c) cats.

<p>m1: first deciduous molar, m2: second deciduous molar, M1: first permanent molar, P1: first permanent premolar, P2: second permanent premolar. Scale bar = 5 mm</p