Thickness of facial gingiva.

Gingival thickness was measured in 10 subjects with healthy gingiva on the facial aspect of selected maxillary and mandibular teeth at the depth of the gingival sulcus and midway between the sulcus depth and mucogingival line. Measurement instrumentation, consisting of a differential transformer coupled to an oscillator and digital voltmeter was sensitive to the travel of a probe from the gingival surface to tooth surface or alveolar bone. The probe assembly was accurate to 0.01 mm and the average range of differences in replicate measurements under a variety of conditions never exceeded 0.15 mm. 1. Free gingival thickness averaged 1.56 mm + 0.39, attached gingival thickness averaged 1.25 mm + 0.42 and the total mean thickness for all areas measured was 1.41 mm. 2. Thickness in mandibular free and attached gingiva and maxillary free gingiva increased from anterior to posterior. Thickness in maxillary attached gingiva remained fairly constant. 3. Thickness measured at the depth of the sulcus was directly proportional to the free gingival width. 4. Thickness measured midway between sulcus depth and mucogingival junction was inversely proportional to attached gingival width.