The purpose of this cross-over clinical research is to evaluate the cleaning efficacy of toothbrushes tufted with two types of tapered bristles and end rounded bristles in removal of interdental plaque with clinical measurement (Plaque Index) and objective measurement (digitally measured plaque area). This study will demonstrate the influence by a type of processing bristles on removal of interdental plaque and determine an agreement between the different evaluation methods.

This is a randomized evaluator-masked crossover study with 10 subjects. Subjects will be randomly allocated to three test groups. Subjects will use the assigned toothbrush at baseline appointment and two times a day for a week. Plaque Index and plaque area will be assessed before/after one time use at baseline and Day 7. Subjects will be assigned to another toothbrush after one week wash-out period.

Inclusion Criteria: Individuals may be included in the study if they meet all of the following inclusion criteria:

• Must have read, understood and signed an informed consent prior to being entered into the study
• Must be 18 to 70 years of age, male or female
• Have at least 20 natural or restored teeth
• Must have average Plaque Index of Ramfjord teeth at baseline greater than 2(Quigley and Hein) at screening
• Agree not to have a dental prophylaxis or any other elective, non-emergency dental procedures (other than those provided during the study) any time during the study
• Agree to refrain from regular oral hygiene regimen for 24 hours and eating for 4 hours before the appointment in the study
• Agree to abstain from the use of any dental products other than those provided in the study
• Agree to comply with the conditions and schedule of the study

Exclusion Criteria: Individuals are not eligible for participation in this study if any of the following are noted:

• Physical limitations or restrictions that might preclude normal tooth brushing
• Evidence of gross oral pathology
• Presence of severe gingivitis with 30 or more sites showing bleeding on probing
• Evidence of major soft tissue lesions or trauma at the baseline visit as determined by the Investigator/Examiner
• Chronic disease with concomitant oral manifestations
• Subjects who are currently undergoing, or require, extensive dental work, orthodontic treatment or periodontal surgery or orthodontic treatment in the preceding 3 months
• Currently using bleaching trays
• Eating disorders
• Recent history of substance abuse
• Smoking >10 cigarettes/day
• Participation in other clinical studies within 14 days of screening

Up to 1 week

Plaque area is not measured by image analysis due to: 1. The plaque area is so small as area% in a total region of interest. 2. Most of plaque on teeth surface of buccal side was removed after 2-minute brushing in most of subjects, so it is difficult to detect their difference. 3. Quality of accumulated plaque, e.g. thick but shallow area vs. thin but broad area, is hard to do the assessment. 4. Some photos were not appropriate for image analysis due to being a little out of focus.