The primary objective of this study was to elucidate the impact of dental intervention on patients’ QoL, explore shifts in oral symptoms and distress, and evaluate the efficacy of dental support.

During the initial examination, it was evident that there was a concerning pattern of inadequate oral hygiene among the patients. Many had not visited a dentist for over a year.

The dental health status was distressingly poor, with patients showing oral pathologies, underscoring the requirement for more comprehensive dental care within palliative care settings. The pathologies encompassed dental calculus, infections of the oral cavity and oral rhagades. These findings are in line with results already presented by Singh et al. in India in 2021 and underscore the global relevance of the problem of inadequate oral healthcare in palliative patients [3].

Almost half of the dentures analysed in this study exhibited defects and were found to be unclean. Patients reported pressure sores and sharp edges. Due to severe weight loss, patients experienced dissatisfaction with the retention of their dentures. Difficulties with the dentures were previously documented by Guggenheimer et al. [16] citing xerostomia as the primary cause.

In addition to radiotherapy in the head and neck region, possible reasons for this include the use of medication that causes dry mouth or the combined use of several medications [17]. So 95.1% of the palliative patients taking part in the study were taking more than 5 different medications, which is essential for appropriate pain therapy. Severe dry mouth is considered a side effect of the therapy [9, 18].

In addition, many patients suffered from oral mucositis. This is in line with a study conducted by Pulito et al. (2020) citing that 90% of patients with chemotherapy and radiotherapy in the head and neck region suffer from this inflammatory reaction. This leads to a deterioration in quality of life, delays in further treatment, and a poorer prognosis [19]. According to Nicolatou-Galitis et al. (2001), additional infections often occur in this inflamed environment, which is also emphasised by our study [20]. Patients also suffered from candidiasis and herpes simplex.

Oral quality of life at T0 was assessed utilizing the EORTC QLQ-OH 15 questionnaire. The results of the multilevel scale for assessing oral health-related quality of life show an OH-Qol score (mean 60.60, SD 23.668). Compared to the study by Hjermstad et al. (2016), palliative patients rated their oral quality of life similarly poorly to cancer patients [21]. These results are also reflected in the symptom scores OH-sticky saliva (mean 38.10, SD 36.619), OH-sensitivity (mean 35.52, SD 32.156), OH-sore mouth (mean 23.87, SD 31.156), and OH-dentures ill-fitting (mean 38.63, SD 31.714).

Oral diseases and symptoms were found to improve in the presence of a dentist, notably in the successful treatment of xerostomia (improvement of 62%), candidiasis (improvement of 18%) and oral mucositis (improvement of 18%). These findings underscore the significant impact of dental intervention on enhancing oral health outcomes in palliative patients.

Furthermore, statistically significant improvements were achieved in the patients’ self-assessed health-related quality of life, OH-QoL (p < 0.001) and in symptom scales such as OH sore mouth (p < 0.001), OH sticky saliva (p < 0.001), OH sensitivity (p < 0.001) and OH information receives (p < 0.001), for which there is no other published experience to date.

The dental examinations in the setting of this study could easily be carried out at the patients’ bedside or within their patient rooms. As already shown by Schimmel et al. (2007), most palliative patients are physically severely restricted, highlighting the recommendation of offering examination in a wheelchair or while the patient is in bed [22]. Patients frequently utilized their own hygiene products, a practice that proved beneficial as it allowed for the inspection and replacements of items as needed. All recommended medication and aids were conveniently kept on the bedside table, ensuring visibility for both caregivers and relatives regarding what needed to be utilized. It was easy to integrate the examination into the daily routine. Direct communication with the nursing staff and senior physicians proved to be beneficial for diagnosis and counselling. The importance of such collaboration is also emphasised by Malik et al., who assert the essential role of nurses in recognizing the necessity for oral care at the end of a person’s life [23].

The selected electronic questionnaires EORTC QLQ-C30 and OH15 on the QL-Recorder and circumscribed dental interventions were found to be feasible. In their large international study, Hjermstad et al. also came to the conclusion that the QLQ-C30 in combination with the OH15 module adequately records oral problems [21].

The OH15 module was chosen for its inclusion of symptom scales such as mouth ulcers, sticky or absent saliva, sensitivity and problems with dentures in addition to the functional oral health-related quality of life scale. Similar to the findings of Gorges et al., we conclude that the EORTC QLQ-OH15 module covers the most important topics despite the brevity of the questions and is well accepted by the patients [24]. Immediately after the survey, the results were recorded in the patient file and made available to the nursing staff. This enabled doctors and nursing staff to quickly gain an impression of the patient’s symptom burden and complaints.

A key limitation is that the sample was recruited exclusively from patients in a single institution. This limits the generalisability of the results to a broader patient population. Furthermore, many patients were excluded from the study due to the advanced stage of their disease, which further limits the representativeness of the sample. Another critical point is the short observation period of only seven days, without subsequent follow-up examinations, which does not take into account the long-term effect of dental interventions on the quality of life of palliative patients.

Despite these limitations, the study has significant strengths. A notable advantage is its potential reproducibility of the study, as it can be replicated in various clinical and outpatient settings. This reproducibility is crucial for validating the results and ensuring their applicability in different care contexts. In addition, the feasibility of the study requires little effort, as only one dentist needs to be involved. This enables a broad application of the study methodology and promotes understanding of the importance of dental care in palliative care. By repeating the study under varying conditions, the evidence base on the oral health of palliative care patients can also be systematically expanded and deepened.

The available data suggest that systematic dental care can significantly improve the oral health of palliative patients at the end of life. Despite this evidence, there is a lack of comprehensive studies looking at the implementation and impact of routine dental care in palliative care, as also highlighted by Walsh et al. in 2023 [25]. This research gap emphasises the need for further investigation to develop a deeper understanding of the specific needs and optimal treatment strategies for this patient group, as well as the importance of a palliative care guideline that provides clear treatment recommendations and support for typical oral cavity conditions. Although Jones et al. published such a guideline specifically for patients with progressive cancer in 2022. This guideline provides general information and emphasises the importance of oral care in palliative care [26].

The specific intervention by a dentist and the intervention and detailed recording of quality of life using the EORTC-QLQ OH 15 appears to be an innovative research approach and should be investigated further in the future. Such a concept is currently unique, as there are no comparable studies in the literature. In view of the novelty and significance of the results, further research perspectives open up that should aim to deepen the findings and promote the practical implementation of these interdisciplinary treatment approaches.

The implementation of effective oral healthcare in clinical palliative care is a multidisciplinary challenge that extends beyond routine consultation with a dentist. A key strategy to improve the oral health of palliative care patients is the targeted training of caregivers, as suggested by Viebranz et al. [27]. This study emphasises the positive effects of individualised oral hygiene training on oral and denture hygiene in geriatric patients, highlighting the need to educate caregivers in the recognition and treatment of oral disease.

In addition, Shimotsu et al. (2024) point out specific problems such as candidiasis and emphasise the importance of regular inspections of the oral cavity by nursing staff. These measures are crucial to reduce the prevalence of oral pathologies and to initiate adequate therapeutic measures at an early stage, which both improve patients’ QoL and help prevent potential complications [28].

The present research findings emphasise the need to consider oral health as an integral component of palliative care and to develop and implement appropriate care strategies. The identification of prevalent oral health problems underlines the urgency of integrative dental care within palliative care settings, aimed to enhancing the QoL for palliative patients and minimising the adverse effect of compromised oral health on overall health in the last phase of life. With very little dental effort and simple ward and bedside treatments, significant improvements in the oral symptom burden of critically ill palliative patients can be achieved. This contributes to improved care status, relief of distressing symptoms, and ultimately improved quality of life. The results of this study strongly support the consideration of dental support as an integral part of palliative care units.