Poor oral health is a significant concern, particularly in medically compromised patients. Preventive interventions, including improving dental literacy, promoting good oral health related habits, and incorporating oral aid devices such as water flossers [1], are crucial for preventing oral diseases.

Oral health greatly affects the quality of life, overall health, and dietary habits of elderly individuals. Risk factors for poor oral health include salivary dysfunction, medical conditions, polypharmacy, swallowing and dietary difficulties, functional dependence, reliance on assisted oral care, and lack of supervision by dental professionals. Additionally, income-related disparities contribute to oral health disparities among aged people [2-4]. Other prevalent risk factors for poor oral health include financial disadvantage, functional dependence, residence in institutions, smoking, irregular dental attendance, caregiver burden, prior experience of oral diseases, dementia, swallowing difficulties, and nutritional issues. Overcoming barriers to oral health care, especially in seniors with dementia, is crucial, given the significant challenge of accessing the oral cavity. Clear inclusion of oral health care in daily care activities is essential for maintaining their quality of life.

The COMORAL^Ⓡ (SMDsolutions, Seoul, Korea) multi-channeled oral irrigation (MCOI) device provides thorough tooth surface cleaning with pressurized pulsatile water jets while simultaneously suctioning oral irrigated water to prevent pulmonary aspiration. In a controlled trial comparing 28-day use of the MCOI plus toothbrushing to toothbrushing alone, significant differences were observed in plaque index, gingival index, bleeding on probing (BOP), and pocket depth as a periodontitis biomarker [5]. Also, a study involving healthy volunteers who received dental scaling 2 weeks prior and used the MCOI for 3 consecutive days without toothbrushing showed significant improvements in plaque index, Sulcus Bleeding Index, and BOP, indicative of periodontal health. Additionally, there was a notable positive alteration in the oral microbiome [6]. Additionally, there was a noticeable reduction in malodor even after two weeks of using MCOI compared to the malodor levels observed before its use [7].

In this case report, we explored the usefulness of a MCOI device in a medically compromised patient with conditions such as dementia and stroke. To evaluate oral health status, we examined indicators like tongue coating and dryness before and 2 days after MCOI use. Additionally, we visually assessed serial turbidity and food residues in oral irrigated water collected by the device to gauge its effectiveness in oral cleaning.

A socially isolated 74-year-old female, weighing 62 kg and measuring 162 cm, with long-standing dementia. She recently experienced a subdural hemorrhage in October 2021 and suffered a right femur neck fracture in January 2022 and underwent total hip replacement in May 2022. She visited a Rehabilitation Hospital on August 24, 2022 to enhance cognition and activities of daily living (ADL), where she has been followed up until now.

The patient exhibits moderately severe dementia having a Korean Mini-Mental State Examination (K-MMSE) score of 3-12 out of 30 and a Global Deterioration Scale (GDS) of 6-7 out of 7 (Table 1). Despite this, she remains alert. She experiences musculoskeletal pain throughout her body, likely due to quadriplegia as a sequela. Her blood test results are generally within the normal range, except for a hemoglobin level of 9.8 g/dl, indicating vitamin B12 deficiency anemia.

Table 1 . Basic information of the patient having dementia and stroke

	1st Adm (2022.08.23)	2nd Adm (2023.01.16)	3rd Adm (2023.09.08)	Present Day 0
Height (cm)	162	162	162	162
Weight (kg)	48	54	62	62
K-MMSE	3	12	11	11
GDS	7	6	6	6
BBS	n/aa	8	4	7
FMA-UE (right/left)	56/37	55/40	63/42	63/42
FMA-LE (right/left)	0/0	18/18	17/17	17/17
MBI	13	31	31	31

^aNot available.

K-MMSE: Korean Mini-Mental State Examination, GDS: Global Deterioration Scale, BBS: Berg Balance Scale, FMA-UE: Fugl-Meyer Assessment-Upper Extremity, FMA-LE: Fugl-Meyer Assessment-Lower Extremity, MBI: Modified Bathel Index.

The patient has a history of right shoulder dislocation, right Achilles tendon injury, sciatica, neurogenic bladder, menopausal osteoporosis and degenerative knee arthritis. There is no history of hypertension, diabetes mellitus, smoking, or drinking. The patient has 4 children, but only one son occasionally provides care for her. She experiences insomnia and anxiety, although depression has not been confirmed. There are no other reported systemic diseases. The patient is currently taking five or more medications; donepezil and choline alfoscerate for dementia, folic acid for anemia, mirabegron for urinary incontinence, diazepam for anxiety, and quetiapine for sleep issues. The oral examination revealed severe gingival inflammation and multiple dental caries (Figure 1). Despite poor oral hygiene, there was no severe teeth mobility, and the patient had no history of recent dental hygiene education, denture use, or dental treatment within the past 6 months. Addi-tionally, the patient had not received any periodontal treatment previously. We inquired about symptoms including dry mouth, alterations in taste sensation, oral pain, as well as signs of oral frailty such as chewing and swallowing difficulty, and phonation issues, fever, cough, and tooth mobility. The patient reported the absence of all these symptoms. The patient has 22 remaining teeth and can produce the sound “ta” 12 times in 5 seconds. The patient practices oral health-related behaviors such as sugar avoidance, twice-daily tooth brushing without oral aid devices, twice-daily tongue cleansing, toothbrushing lasting 2-3 minutes per session, and drinking water more than three times daily. However, cognitive impairment precludes the evaluation of the Geriatric Oral Health Assessment Index (GOHAI).

Figure 1. Oral photo showing poor oral hygiene of a 74-year-old patient having chronic stroke and moderately severe dementia.

The malodor of the patient was measured according to the user’s guide provided by the manufacturing company (Twin Breasor Ⅱ, iSenLab, Seongnam, Korea). The results showed hydrogen sulfide (H₂S) at 2.52 ng/10 ml, 188 ppb, and methyl mercaptan (CH₃SH) at 3.23 ng/10 ml, 171 ppb, respectively. These findings suggest moderate pathological halitosis.

The tongue coating was evaluated before and immediately after using the MCOI device at Day 0 and Day 2. We used WTCI suggested by Winkel et al. [8]. Shortly, the dorsum of the tongue was notionally divided into six areas, i.e. three in the posterior and three in the anterior part of the tongue. The tongue coating in each sextant was scored as 0=no coating, 1=light coating and 2=severe coating. The tongue coating value was obtained by the addition of all six scores, range 0-12. On Day 0, the WTCI score decreased from 4 to 3 after MCOI use, and on Day 2, the WTCI score was 0 both before and after MCOI use (Table 2).

Table 2 . Oral hygiene changes before and after MCOI use

	Day 0 (2024.01.31)	Day 2 (2024.02.02)
Tongue coatinga	4/3	0/0
Turbidityb	3/3/2	3/3/2
Food residuec	3/3/2	3/2/2

^aBefore MCOI/after MCOI, ^b,cMCOI cycle 1/cycle 2/cycle 3.

The turbidity and food residue of the oral irrigated water collected by the MCOI were assessed as indicators of oral cleanliness and the effectiveness of the oral irrigation process. The mouth-rinsed water collected after MCOI use served as an alternative method for collecting saliva to assess oral health, as it can be obtained quickly and easily compared to traditional saliva collection methods [9,10]. Visual grading was performed using a 3-point Likert scale, enabling easy assessment by any people without dental expertise (Tables 2, 3).

Table 3 . Visual assessment of turbidity and food residue in the oral irrigated water

	Turbidity	Food residue
1	Almost clear	Rarely seen
2	Whitish cloudy	Small amount of food residues
3	Very yellow cloudy	Lots of food residues or biofilms
Total

Before using the MCOI device, the patient received detailed instructions on how to use the COMORAL^Ⓡ device (Figure 2) [7]. Following the Tell-Show-Do principle, she was allowed to touch and feel the MCOI device before its use and instructed to insert the mouthpiece shaped WATERET^Ⓡ into her mouth. She was informed that they could stop the device at any time if she encountered difficulties to ensure their safety during MCOI use. There were no interruptions. The device was used twice, with oral irrigation conducted using 500 ml of clear water at 37℃ for approximately 1 minute each time. The turbidity of the oral irrigated water was visually measured three times for each session. To maintain measurement consistency, patients were instructed to only perform toothbrushing immediately before the assessment. After using the MCOI, she noted a noticeable improvement in oral cleanliness compared to before use and satisfied with the MCOI use (Figure 3).

Figure 2. The MCOI is composed of (A). The MCOI device includes simul-taneous a water ejection and suctio-ning system with pumps and 700 ml water tanks. (B) It features a 2-way connecting tube for both clean water influx and rinsed water efflux. (C) The mouthpiece contains 60 nozzles for pressurized water delivery to the gum line, separating clean and oral rinsed water. (D) A schematic repre-sentation of pressurized pulsatile water spray through multiple chan-nels [6].

Figure 3. Visual turbidity and food residue were observed in the oral irrigated water collected from the MCOI device on 2 occasions: Day 0 (A) and Day 2 (B). Each time, turbidity was noted after 3 consecutive oral irri-gation cycles. The turbidity showed oral cleansing effect after consecutive MCOI use.

Easy-to-use and reliable oral health assessment tools used by caregivers, rather than dental professionals, for these patients are crucial for maintaining their oral health. In reality, caregivers often lack specific routines for assisting with oral health care, with other activities often being prioritized over oral care [11].

The turbidity can be observed visually or using a turbidimeter [9,10] considered to reflect oral hygiene levels and associated to the risk of oral health including dental caries and periodontal diseases, as well as the development of oral malodor in periodontitis patients [9].

The mechanism of the MCOI device is similar to various water flossers which typically require users to position a single nozzle precisely at the junction between the tooth and gum of each tooth and then manually move the water nozzle along this line [1]. Originally, COMORAL^Ⓡ is designed for children, disabled and elderly people to effectively manage their oral health, whether independently or with caregiver assi-stance. This MOCI device has been intricately engineered with the goal of reducing oral bacterial load, even in subgingival areas.

Further investigation is warranted using interviews and other methodologies, such as observation, to complement self-reporting as a measure of care givers’ oral care activities.

In conclusion, oral care is still challenge in medically compromised patients. Our 74-year-old patient, managing multiple health conditions and undergoing polypharmacy, showed enhanced oral hygiene evidenced by a decrease in tongue coating score and improved turbidity status after using the MCOI device at 2 days later.

We are grateful to the patient for generously providing written informed consent for the publication of her clinical details and clinical images. This work was supported by the Technology development Program (S3327227) funded by the Ministry of SMEs and Startups (MSS, Korea).

In the declaration of conflicts of interest, it is worth noting that all authors involved in this with the exception of Hyun Jeong Kim, who serves as the CEO of SMDsolutions Co., Ltd.