National Board Dental Hygiene Examination (NBDHE) Dental Hygienist Practice Test

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Prepare for the National Board Dental Hygiene Examination with engaging quizzes. Access a variety of multiple-choice questions, each with detailed explanations and study tips, to confidently pass your NBDHE!

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What is the ideal angle for instrumentation during calculus removal?

  1. 30-40 degrees

  2. 45-55 degrees

  3. 60-80 degrees

  4. 90-100 degrees

The correct answer is: 60-80 degrees

The ideal angle for instrumentation during calculus removal is between 60 to 80 degrees. This angle is optimal for effective scaling because it allows the clinician to achieve a proper balance between the effectiveness of the instrument and the preservation of tooth structure. At this angle, the cutting edge of the scaler or curette is properly engaged with the calculus deposit, maximizing the removal efficiency while minimizing the risk of damaging the enamel or periodontal tissues. In contrast, a steeper angle (like those suggested in other options) often leads to insufficient contact with the calculus, resulting in inadequate removal. If the angle is too wide or too narrow, it can also lead to increased risk of slipping, which might cause trauma to surrounding soft tissues or leave residual calculus. Thus, maintaining the correct angulation is crucial for effective, safe instrumentation during dental hygiene procedures.