A new classification system of periodontal and peri-implant diseases and conditions was proposed by consensus of world experts in 2017. Since then there has been ongoing debates among periodontists regarding the application of the new classification. This study aims to shed light on the current understanding of the new classification among Egyptian periodontists.

This study was approved by the Research Ethics Committee of Faculty of Dentistry Beni-Suef University (ID #FDBSUREC/27022019/AM) and was conducted in full accordance with the World Medical Association Declaration of Helsinki 1975, revised in 2003. The questionnaire was anonymous with no personal identification data. Completion and submission of the questionnaire was considered an approved informed consent to participate in the study by the Research Ethic Committee.

The questionnaire was designed by the authors and pilot tested among a group of 12 periodontists for validation. Afterwards, adjustments were made to ensure a clear and comprehensive version of the questionnaire. The questionnaire had a cover letter explaining the nature and purpose of the survey and comprised 15 questions. The first six statements of the questionnaire were descriptive in nature addressing the participant's demographics, and the seventh was a question whether the participant is aware of the new PDL classification or not. Only those who were aware of it were asked to proceed to 13 multiple choice questions using Likert scale; ranging from strongly disagree to strongly agree or from excellent to poor, in addition to "I don't know" option (8). There were also three open ended questions for further comments at the end of the questionnaire.

Inclusion Criteria:

• periodontists

Exclusion Criteria:

• non periodontists

periodontists in various universities

ONCE PUBLISHED

ONCE PUBLISHED