Please assess the completion status of the following clinical trial:

Trial Title: Efficacy of Three Toothpastes Using an in Situ Caries Model

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: CROSSOVER
- Observational Model: None
- Primary Purpose: BASIC_SCIENCE
- Time Perspective: None
- Masking: SINGLE
- Phase: None
- Number of Arms: 6.0

Eligibility Criteria:
Inclusion Criteria:~1. Demonstrates understanding of the study.~2. Aged 18 to 85 years.~3. Understands and is willing, able and likely to comply with all study procedures and restrictions.~4. Has good general health (in the opinion of the investigator or medically qualified designee).~5. A salivary flow-rate in the range of normal values (unstimulated whole saliva flow- Rate ≥ 0.2 g/minute (min); gum base stimulated whole saliva flow-Rate ≥ 0.8 g/min).~6. Currently wearing a removable mandibular partial denture with sufficient room in the posterior buccal flange area to accommodate two enamel specimens.~7. Have no current active caries or periodontal disease and all restorations in a good state of repair.~8. Willing and capable of brushing their natural teeth with the lower partial denture in place.~Exclusion Criteria:~1. Pregnant or breast feeding women.~2. Known or suspected intolerance or hypersensitivity to the study materials or their stated ingredients.~3. Currently taking antibiotics or have taken antibiotics in the two weeks prior to the screening visit.~4. Unable to measure product weights accurately using the assigned study scale as determined by the study staff as demonstrated.~5. Participation in another clinical study or receipt of an investigational drug within 30 days of the screening visit.~6. Have received a professional fluoride treatment within 14 days of randomization to the first treatment.~7. Recent history (within the last year) of alcohol or other substance abuse.

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 85 Years
- Healthy Volunteers: t

Study Arms:
- Experimental Dentifrice1 (Type: EXPERIMENTAL): Participants will brush their natural teeth with a pre-wetted toothbrush and their assigned dentifrice for one timed minute, ensuring the enamel specimens retained within their mouths are not directly brushed. Participants should then rinse their mouths with 15ml of tap water for approximately 10s.
- Experimental Dentifrice 2 (Type: EXPERIMENTAL): Participants will brush their natural teeth with a pre-wetted toothbrush and their assigned dentifrice for one timed minute, ensuring the enamel specimens retained within their mouths are not directly brushed. Participants should then rinse their mouths with 15ml of tap water for approximately 10s.
- Experimental Dentifrice 3 (Type: EXPERIMENTAL): Participants will brush their natural teeth with a pre-wetted toothbrush and their assigned dentifrice for one timed minute, ensuring the enamel specimens retained within their mouths are not directly brushed. Participants should then rinse their mouths with 15ml of tap water for approximately 10s.
- Reference Product 1 (Type: PLACEBO_COMPARATOR): Participants will brush their natural teeth with a pre-wetted toothbrush and their assigned dentifrice for one timed minute, ensuring the enamel specimens retained within their mouths are not directly brushed. Participants should then rinse their mouths with 15ml of tap water for approximately 10s.
- Reference Product 2 (Type: ACTIVE_COMPARATOR): Participants will brush their natural teeth with a pre-wetted toothbrush and their assigned dentifrice for one timed minute, ensuring the enamel specimens retained within their mouths are not directly brushed. Participants should then rinse their mouths with 15ml of tap water for approximately 10s.
- Reference Product 3 (Type: ACTIVE_COMPARATOR): Participants will brush their natural teeth with a pre-wetted toothbrush and their assigned dentifrice for one timed minute, ensuring the enamel specimens retained within their mouths are not directly brushed. Participants should then rinse their mouths with 15ml of tap water for approximately 10s.

Based on this trial design, predict the completion outcome and termination type (if applicable).