Aims: To profile the oral microbiome of children with type 1 diabetes mellitus, and to compare it to healthy children while taking into account other aspects of the oral environment.

Research: exploring the differences between oral microflora of children with type 1 diabetes mellitus and control healthy children using salivary microbiome. The investigators will furthermore intend to analyze the differences of salivary flow rate, pH, glucose, calcium, inorganic phosphate and urea between the two groups.

Saliva from 50 children ages 5 to 15 years old who had been diagnosed with type 1 diabetes mellitus and are followed at the Pediatric Endocrinology Clinic, Hadassah University Hospital Mt. Scopus and Ein Kerem, Jerusalem, Isreal, will be compared to 50 healthy children, preferably their siblings, matched in age and gender. Each patient or their legal guardian will sign an informed consent to participate in the study. The investigators will request a permission to access the medical records of the patients. Data will be collected from patient medical history. The investigators will measure salivary flow rate, pH and glucose, salivary Calcium, inorganic phosphate and urea and perform microbiome analysis and 16S rRNA gene-based analysis comparing children with diabetes to healthy children.

Inclusion Criteria:

• Children with type 1 diabetes mellitus

Exclusion Criteria:

• Children Unable to give saliva sample
• Children On antibacterial medicaments

Saliva from 50 children ages 5 to 15 years old who had been diagnosed with type 1 diabetes mellitus and are followed at the Pediatric Endocrinology Clinic, Hadassah University Hospital Mt. Scopus and Ein Kerem, Jerusalem, Isreal, will be compared to 50 healthy children, preferably their siblings, matched in age and gender.