Ling Zhan, DDS, PhD


Dr. Ling Zhan (DDS, PHD) is an assistant professor in residence with a dual appointment in the Department of Preventive and Restorative Dental Sciences (PRDS) and the Department of Orofacial Sciences. She completed a DDS degree in 1992 and holds a PhD in Cariology in 1997 from the College of Stomatology at West China University of Medical Sciences in Chengdu, China. 

There, she served as an Assistant Professor in the Department of Cariology, Periodontics, Endodontics and Oral Medicine for 3 years. She focused on teaching and research related to the molecular biology and microbiology of dental caries. Dr. Zhan came to UCSF as a Lee Hysan scholar in 2000.

In 2008, Dr. Zhan completed her pediatric dentistry residency at UCSF and joined the university as an assistant professor in-residence. Her research since 1997 has been focused on the etiology, microbiology, and prevention of dental caries. Although she specializes in pediatric dentistry, Dr. Zhan's recent research has been focused on caries management by risk assessment, the route and mechanisms of cariogenic bacterial transmission, antibacterial therapy to reduce or eliminate cariogenic bacterial transmission, and dental caries in high-risk adults and children.

Dr. Zhan has been involved in two CAN DO pilot projects since 2001. The first was a pilot project entitled Povidone Iodine Treatment Following Dental Surgery to Reduce the Bacteria that Cause Tooth Decay, where she served as a co-investigator and played a major role in patient recruitment, follow-up, microbiological assays, data analysis, and manuscript writing. Dr. Zhan was also the principal investigator (PI) of another pilot project called A Comparative Study of Cariogenic Bacterial Populations in Children funded in 2003-2004. The overall objective of the study was to investigate cariogenic bacterial risk and measurement factors related to early childhood caries.

The results from the two pilot studies have led to further research in the following directions: diversity of mutans streptococci (MS) and the presence of S. sobrinus in relation to early childhood caries (ECC). Using MS genotypes isolated from the pilot project, she further investigated the virulence factors related to caries in children. She found that acid tolerance, acid production, and mutacin formation capabilities of MS are related to caries status in children. She also investigated the virulence factors related to the transmission of MS in children.

She is currently a PI in a new project focusing on the Effect and Mechanism of Xylitol on Early Childhood Caries.