The Effect of Instructed Dental Flossing on Interdental Gingival Bleeding: A Randomized Controlled Clinical Trial

In this study, half of the participants will be asked to floss as normal, while the other half will receive professional instructions on flossing from a dentist. The investigators want to see if the participants who have professional flossing instructions are able to remove plaque in between the teeth more effectively, and have less gum bleeding over time. The investigators also want to see if participants who receive professional flossing instructions get better at the technique over time, and if they can match the dentist's skill by the end of the study.

Primary Aim: To determine whether subjects instructed with a specific flossing technique have less gingival inflammation as evidenced by bleeding on probing (BoP) than subjects without flossing instructions.

Secondary Aim: To compare the effect of flossing by a dental professional with a patient's self-flossing following instruction in removing interdental plaque.

Secondary Aim: To compare the completeness of plaque removal by the subjects instructed during the initial visit (Group A \[test\]) with their completeness at the final (fourth) visit.

Secondary Aim: To compare the clinician's completeness of plaque removal at the fourth visit with the completeness of plaque removal by the subjects in both groups (Groups A \[test\] and B \[control\]). Each group will be analyzed separately. In Group A, a comparison of the plaque removal by the subjects and by the clinician will made with respect to the completeness at the first visit versus the final visit.

Eligibility Criteria:
Inclusion Criteria:

* At least 18 years of age
* Subjects must show \> 20% interproximal sites (mesial facial and mesial lingual and distal facial and distal lingual) with BoP. This includes mesial and distal sites next to edentulous areas.
* Subjects must have \> 24 natural teeth including teeth with crowns with margins confluent with the natural tooth as long as they do not violate the biologic width.
* Third molars will be excluded from study; unless the third molars are in the anatomical position of second molars. However, subjects with third molars present will be accepted into the study unless there are other factors that exclude them.
* Subjects must report having had a professional dental prophylaxis within four months of beginning the study.
* Subjects must be willing to floss daily and to be taught and use a specific technique of flossing.

Exclusion Criteria:

* Subjects who use tobacco products.
* Subjects with fixed or removable orthodontic appliances
* Subjects with splinted fixed prostheses.
* Subjects who are incapable of flossing their teeth
* Subjects with defective interproximal restorations or interproximal caries that are clinically evident and impacting gingival health.
* Subjects where malposed teeth preclude the use of floss
* Subjects with probing depth greater than or equal to 5mm.
* Subjects who are pregnant (self-reported) due to the greater bleeding tendency due to the hormonal changes.
* Subjects with a systemic disease that affects the gingiva or are taking medications of which affect the gingiva.
* Non-English speaking subjects, as study assessments and instructions will be in English only. There is no direct benefit to subjects for taking part in this study, therefore the exclusion of non-English speaking subjects is not an ethical concern.