This study will be conducted to evaluate the effectiveness of using dissolving Xylitol chewable tablets versus xylitol chewing gum with bedridden geriatric patients in increasing salivary pH and decreasing bacterial count in both saliva and interdental plaque.

This study will be conducted to evaluate the value of using dissolving Xylitol chewable tablets versus xylitol chewing gum with bedridden geriatric patients ,as an alternative to tooth brushing and mouth rinsing, in increasing salivary pH and decreasing bacterial count in both saliva and interdental plaque.plaque and salivary sampling will be taken in certain time ,at baseline T0, then after 5minutes T1, then at 15 days T3. Salivary pH will be measured by using pH meter and streptococcus mutans bacterial count will be calculated through culture in mitis salivarius bacitracin

Inclusion Criteria:

1. Age range above 65 years old
2. Bedridden patients
3. Males or females
4. Concious patients
5. Co-operative patients approving to participate in the trial.
6. Subjects who signed informed consent

Exclusion Criteria:

1. Individuals had taken antibiotics during the last four weeks or anticipated doing so during the study
2. Subjects who wore removable prosthesis
3. Patients with systemic diseases that have any oral manifestations
4. History of Smoking
5. Allergy to any of chewing gum or tablets ingredients
6. Evidence of tempromandibular joint disorders
7. Presence of intraoral infections
8. Currently using any mouth rinse

A paper of the research will be published internationally after results calculation

The operator will be blinded to material and assessors will be blinded to the material assignment.