Re-mineralization Effects of Sugar Free Chewing Gum Sweetened With Different Sugar-substitutes

Inclusion Criteria: * Consent Informed Consent Form signed by parent or legal guardian permitting participation of their children. * Be cooperative and able to be examined in the whole study duration. * Aged from 8 to 13 years. * General Health: Good general health (in the opinion of the investigator) without clinically significant and relevant abnormalities of medical history such as diabetic, etc. * Oral Health: Display 6 permanent front teeth and two maxillary buccal surfaces with visual evidence of active initial enamel carious lesions (de-mineralized but not cavitated); No any form of intraoral prostheses or appliances, clinical signs of severe gingivitis or periodontitis, temporomandibular joint disorders, and malocclusions or chronic onychophagia * Oral Hygiene: have good oral health habits, brushing teeth at least once per day * No medical or pharmacotherapy history that might affect the outcomes of the study, e.g. use of mouthwash, gels, or chewing gum containing antimicrobial agents during the previous 3 months Exclusion Criteria: * Disease: Presence of chronic debilitating disease, or any condition or other chronic disease which the investigators think not suitable for the study. * Allergy/Intolerance: Be allergic to both maltitol and xylitol, oral care products, personal care consumer products, or their ingredients. * Current Product Use: usual chewing-gum (of any kind) consumer or sugars-free candies consumer * Clinical Study/Experiment: Participation in another clinical study or receipt of an investigational drug within 30 days of the screening visit.