In the realm of patient care, the concept of Oral Health-Related Quality of Life (OHRQoL) offers insights into how oral health issues affect individuals' overall well-being. For oral health care practitioners, ranging from dentists and dental assistants to dental hygienists and dental therapists, understanding the intricate interplay between oral diseases, treatments, and their effects on patients' OHRQoL becomes imperative. As there are different standards for these oral health care professionals internationally, this study focuses on their roles in the United States (US). This provides the foundation for our systematic review, which delves into the multidimensional impact of OHRQoL within patient populations routinely treated to by dental hygiene and dental therapy providers.

Over a century of presence in the US, dental hygienists have assumed the responsibility of conducting thorough assessments of oral and systemic health, enabling the formulation of precise dental hygiene diagnoses and tailored treatment plans.1, 2 The dental hygienist's scope of practice in the US encompasses a spectrum of interventions, from dental prophylaxis to preventive measures against caries and periodontal diseases, oral hygiene instruction, and oral health education.3,4 It is important to note that the scope of practice for the dental hygienists and dental therapists vary among different states. Dental therapy in the US was developed as an allied dental profession to expand access to oral health care.5,6 Operating with the subset of a dentist's scope of practice7, dental therapists contribute by conducting oral and systemic health care assessments, formulating treatment plans, and executing various preventative and therapeutic treatments (i.e. restorative and emergency palliative treatment) through a collaborative management agreement with a dentist.8,9

As part of the dental team, it is imperative that dental hygienists and dental therapists understand the role and impact of dental patient-reported outcomes (dPRO) in clinical and research settings. The integration of patient-reported perspectives in routine assessment, in conjunction with clinical assessments, enriches the provision of patient-centered care. In order to assess dPROs, it is important to understand the concept of OHRQoL. Rooted in the patient's perceived Health-Related Quality of Life (HRQoL), OHRQoL encapsulates the individual's oral health experience.10 The four-dimensions11 of OHRQoL (Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact) serve as the elements of oral disease-generic dPRO measures (dPROMs) utilized to asses dPROs.12, 13, 14, 15 As Qin et al. mentions in the special issue, the utilization of consistent verbiage supports the aim of standardization for research in this field.15 These dimensions are the fundamental building blocks in understanding and assessing dPROs in OHRQoL. With the goal of increasing effective research to reduce research waste16, oral health professionals and researchers came together to focus on outcomes in cost of care to support value-based oral health care,17 and published the MOM project (Mapping Oral Disease Impact with a Common Metric) in 2021. Since then, MOM has been instrumental in providing oral health impact information through the 4-D framework for various oral diseases and settings.12,18 By conducting systematic reviews on OHRQoL impact for all 4-Ds in adult and adolescent populations, the MOM project has contributed valuable insights into oral health outcomes.19, 20, 21, 22, 23, 24

Aligned with the MOM project's recommendations25 of improving coverage of oral disease impact mapping, the determination of distinct patient populations for the dental hygiene and dental therapy interventions was completed to encompass the larger pool of oral health providers in OHRQoL assessment.7 Upholding the MOM project's call for standardization25, the Oral Health Impact (OHIP) was used as the primary dPROM for assessment in this systematic review.26,27 In addition to the MOM systematic reviews, a previously published methodology paper was also utilized in the development of this project.28 This systematic review aims to identify the 4-D impact of OHRQoL (Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact) in patient populations routinely treated by dental hygiene and/or dental therapy providers. By understanding 4-D impacts, dental hygienists and dental therapists can improve patient-centered care and contribute to value-based oral health care efforts.