Gingival thickness threshold and probe visibility through soft tissue: a cross-sectional study.

Area of Science:

• Periodontology
• Dental diagnostics
• Soft tissue assessment

Background:

• Gingival thickness (GT) is a critical factor in periodontal health and esthetics.
• Assessing GT non-invasively is essential for clinical decision-making.
• Gingival translucency, indicated by probe visibility, is a potential indicator of GT.

Purpose of the Study:

• To determine the threshold of gingival thickness (GT) at which probe visibility changes.
• To establish a reliable ultrasound quantification (USD) cut-off for differentiating thin and thick gingival tissues.
• To correlate probe visibility with specific GT measurements in mandibular incisors.

Main Methods:

• Ultrasound quantification (USD) was used to measure soft tissue thickness in 200 patients at the central mandibular incisors.
• Probe visibility (PB) was assessed using a standard periodontal probe inserted 1 mm into the gingival sulcus.
• Regression analysis and receiver operating characteristic (ROC) curves were employed to identify the GT threshold for probe visibility.

Main Results:

• The probe was not visible at a gingival thickness of 0.82 mm and became visible at approximately 0.69-0.70 mm for both central mandibular incisors.
• Regression models indicated thresholds of 0.82 mm (non-visibility) and 0.69-0.70 mm (visibility).
• ROC analysis confirmed a GT of 0.8 mm as the optimal cut-off for distinguishing probe visibility with high specificity and sensitivity.

Conclusions:

• Gingiva becomes non-transparent, obscuring probe visibility, at a thickness of approximately 0.8 mm.
• A gingival thickness of 0.8 mm serves as a reliable indicator for differentiating thin and thick soft tissues at the mandibular incisors.
• The findings demonstrate high repeatability and clinical relevance for using probe visibility as a diagnostic aid.