Wedged cervical lesions produced by toothbrushing.
OBJECTIVE
To compare the morphology of experimentally induced cervical toothbrush abrasion lesions to teeth demonstrating non-carious cervical lesions in vivo.


METHODS
Eighteen premolars extracted for orthodontic reasons were each subjected to 80 hours (1.4 million strokes) of horizontal brushing in a custom fabricated toothbrushing machine. Toothpaste slurry was applied continuously and specimens were subjected to 300 gms of toothbrushing force. Denture base resin was used to simulate gingival recession of 1 mm and a sulcus width of 0.1 mm. Cervical abrasions were analyzed by optical and scanning electron microscopy and classified as either V-shape/wedged vs. U-shape/rounded lesions. When lesions exhibited both shapes, they were classified as mixed. Shapes of experimentally induced lesions then were compared to naturally occurring ones found on extracted premolars. RESULTSts: Experimentally induced toothbrush abrasion duplicated the classical clinical shapes. Half (9/18) of the experimentally induced toothbrush abrasions exhibited wedged lesions, 28% (5/18) showed a mixed wedged/rounded lesion, and 22% (4/18) showed rounded lesions. Serial photography showed progression of the morphology of the lesions. Toothbrush abrasion apparently begins apical to the cemento-enamel junction, progresses to dentin, and then undermines enamel with loss of the original cemento-enamel junction. Wedged lesions may appear with the apex oriented coronal or apical, or may be symmetrical.
Litonjua
Luis A
LA
Dept. of Periodontics and Endodontics, State University of New York at Buffalo, 250 Squire Hall, 3435 Main St., Buffalo, NY 14214-3008, USA. laldmd@yahoo.com
Andreana
Sebastiano
S
Bush
Peter J
PJ
Tobias
Thomas S
TS
Cohen
Robert E
RE
D001641:Bicuspid / Q000473:pathology; D003743:Dental Enamel / Q000473:pathology; D003804:Dentin / Q000473:pathology; D018450:Disease Progression; D006801:Humans; D008855:Microscopy, Electron, Scanning; D014072:Tooth Abrasion / Q000145:classification / Q000209:etiology* / Q000473:pathology; D019237:Tooth Cervix / Q000473:pathology*; D014099:Toothbrushing / Q000009:adverse effects* / Q000295:instrumentation; D014100:Toothpastes / Q000008:administration & dosage
D014100:Toothpastes