## 1 Introduction  
Regular dental visits play a crucial role in the early detection and treatment of oral conditions, as well as in promoting oral health and educating individuals on oral hygiene [1, 2]. However, due to the inequalities present in the Australian health system, not all Australians are achieving the same degree of oral health [3]. Substantial oral health disparities continue to exist among different groups within the Australian population [4]. In 2022-2023, 52% of Australians visited a dentist [4]. Notably, approximately 20% of adults who were eligible for subsidized public oral healthcare accessed these services [5, 6]. Understanding the utilization of public oral healthcare services is essential due to oral health's impact on overall quality of life. Investigating oral healthcare utilization can shed light on under-represented population groups, often from socially disadvantaged backgrounds. These groups are a priority in Australia's National Oral Health Plan [3]. Evidence shows that eligible individuals from socially disadvantaged backgrounds in Victoria experience poorer periodontal health, and higher rates of dental disease like caries and oral cancer [7; 8; 9]. Research indicates that these groups encounter elevated rates of oral health issues and face significant hurdles in accessing and completing dental care. Access to public oral healthcare in Australia is predominantly determined by the possession of a Commonwealth Health Care or Pensioner Benefit Card. These cards provide individuals with eligibility for subsidized oral healthcare services. However, the allocation of appointments is typically conducted on a \"first-come first-served\" basis. However, the ability of a person to use oral healthcare services (i.e., access) extends beyond mere accessibility; adherence to treatment becomes equally, if not more, significant when involving patients eligible for public dental services, as universal access does not ensure adherence to treatment [10; 11]. Extensive evidence highlights that the outcomes of dental treatment (such as tooth preservation, recurrent pain, and overall quality of life) are directly linked to the completion of the course of care (CoC) [10; 12]. Additionally, studies demonstrate that individuals who do not finish their treatment courses often belong to the high-caries patient group [13; 14]. Furthermore, incomplete and non-compliance with dental treatments pose financial burdens on patients, oral healthcare service providers, and society at large. Therefore, it is important for oral health providers to identify the causes behind the discontinuation of dental treatment, ensuring that oral healthcare needs are treated, and any barriers are effectively addressed. The aim of this study was to investigate the socio-demographic characteristics of adult individuals who had not completed necessary dental treatments within a 12-month period at Monash Health Dental Services in Melbourne, Victoria. Investigating the socio-demographic characteristics and clinical information of patients was hypothesized to identify factors contributing to incomplete dental treatment. The completion of full comprehensive oral care will prevent the deterioration of oral conditions and consequently general health. These profiles offer insights into the specific oral health services required and assess whether current services align with the needs of beneficiaries of public dental services in Victoria. Such an approach serves the public health interest of consumers while benefiting oral health providers. These data hold significance in guiding planners towards developing effective oral health education interventions to increase awareness among patients on the importance of completing CoCs. Further examination of incomplete CoC groups will highlight how to engage with these patients and overcome obstacles that interfere with patient compliance with oral healthcare treatments.