Prevora as a Successful Therapy for Oral Dysbiosis in High-risk, Complex-needs Adults: A Series of Four Patients and a Review of the Literature

by Julie DiNardo, RDH; Irene DeHaan, RDH; Julie Stang, RDH

Oral dysbiosis is an imbalance of bacteria in the dental plaque whereby pathogenic bacteria dominate the biofilm and, in turn, initiate destruction of the hard and soft tissues in the mouth. Caries and periodontal diseases result from oral dysbiosis. A new treatment option for oral dysbiosis called Prevora (10% chlorhexidine) is now available for high-risk, complex-needs adults – those patients who are older and with chronic medical conditions limiting both self-care and tolerability to surgical dental care. We report on four cases of older adults for which Prevora is the only realistic option for treating oral dysbiosis, and we review the literature on Prevora in managing common oral diseases.

Key words: oral dysbiosis, caries, periodontal disease, poor oral health, Prevora


Oral dysbiosis (OD) is a biofilm condition whereby there are too many harmful bacteria in the dental plaque. Symptoms of OD are new or recurrent dental decay and/or new or persistent inflammation of the gums. Conventional treatments for OD such as better personal oral hygiene, topical administration of fluoride and periodontal debridement can have limited antimicrobial effect, particularly in high-risk, complex-needs adults as described below. A new high-strength, long-lasting, broad-spectrum antiseptic treatment, called Prevora, has recently been introduced to manage OD. Prevora is topically applied to the full dentition up to the gingival margin (Figure 2). Here we describe four cases of oral dysbiosis treated with Prevora with persuasive results. We also review the clinical studies of Prevora in treating both caries and periodontal disease.

Fig. 1

Topical application of Prevora
Topical application of Prevora

Fig. 2

Periodontal assessment pre-Prevora Extensive inflammation throughout the mouth (97 sites of bleeding on probing or 67% of all sites)
Periodontal assessment pre-Prevora
Extensive inflammation throughout the
mouth (97 sites of bleeding on probing or 67% of all sites)


In all cases, we received the patient’s or caregiver’s consent to publish all photographic material.

Case 1 – Alzheimer’s patient

A 95-year-old ambulatory female with Alzheimer’s disease presented with a gross accumulation of plaque at the root surfaces, and limited attention span and tolerability to diagnosis and treatment. This patient had received Prevora before the pandemic but none for 2 years. Upon removal of the plaque, the patient had no caries but had 97 sites of bleeding on probing (BOP), constituting 67% of sites in her mouth (Figure 2). One Prevora treatment was administered quickly (5 to 7 minutes) with good tolerance by the patient. The caregiver was requested to return for a second Prevora treatment in a month; this is a longer interval between treatments than the normal Prevora protocol, however, it considered the caregiver’s efforts to transport this patient.

After one month, the patient returned with significantly less inflammation; moreover, the plaque was more readily removed. BOP was 2 or 1% of total sites and the periodontal tissues were pink and healthy (Figure 3). There were no signs of decay. The caregiver was asked to bring the patient back in 3 months.

Fig. 3A

 Periodontal assessment after 30 days and 1 treatment of Prevora
Periodontal assessment after 30 days and 1 treatment of Prevora

Fig. 3B

Bleeding on probing at 2 sites or 1% of all sites. Healthy looking gums with no decay.
Bleeding on probing at 2 sites or 1% of all sites. Healthy looking gums with no decay.

Case 2 – Unresponsive periodontal disease

A 68-year-old female with chronic intra-oral bleeding and moderate periodontal disease was advised about the option of Prevora. The patient presented with 27 sites of BOP, 6 sites with pocket depth between 4 and 5 millimetres, and 1 site more than 5 millimetres pocket depth. The patient received an initial Prevora treatment and returned for the second treatment in two weeks. The patient had no sites of BOP and no pockets greater than 4 millimetres. The patient will continue the standard Prevora protocol of 4 treatments in the first 8 weeks, followed by semi-annual applications with a re-assessment at one year.

Case 3– A new patient with Parkinson’s disease

A 60-year-old male with early-stage Parkinson’s disease since 2018 and with a dry mouth, presented with a recent history of root caries and a strong desire to avoid further dental restoration. The patient had heard about Prevora and requested more information about this new preventive procedure. At baseline, the patient had 26 sites of moderate bleeding on probing, 16 sites at 4 millimetres pocket depth, 4 sites at 5 millimetres and 1 site at 6 millimetres. He had generalized moderate to heavy biofilm, used a manual toothbrush and flossed regularly (Figure 4). After 2 applications of Prevora, BOP was reduced from 26 to 4 sites and inflammation was minimal to non-existent. Two of the bleeding sites were associated with ill-fitting restorative margins. Bleeding at the gingival margins no longer existed and the soft roots at anterior crowns and posterior facial roots had turned hard (Figure 4). The patient is extremely happy with his treatment outcome. Going forward, we have scheduled the remaining two applications in the first 8 weeks of the treatment plan, and a fifth application at his four-month hygiene visit. A sixth application is also scheduled for his annual visit.

Fig. 4A

Before and after two Prevora treatments
Before and after two Prevora treatments. Pre-Prevora baseline

Fig. 4B

After 2 Prevora applications (4 weeks from baseline)
After 2 Prevora applications (4 weeks from baseline)

Case 4 – Palliative care of a bedridden stroke victim with no personal oral hygiene care

This female patient is 79 years of age living in an apartment with her husband. She has been bedridden because of a stroke in 2017. The patient presented with heavy plaque and food debris, severe xerostomia, rampant decay and broken teeth. Her caregiver, although well meaning, refuses to brush the patient’s teeth because he believes there will be too much bleeding given the patient is on blood thinners. The patient’s Power of Attorney (her son) is coordinating her dental care from Montreal. The patient is reasonably cooperative but tolerance to dental care is limited to short appointments. Two Prevora applications have been applied, one month apart along with application of silver diamine fluoride to carious lesions and one restoration with glass ionomer.

One month after the first Prevora application, the patient had markedly reduced oral inflammation along with a reduction in plaque (Figure 5). Before the second application, the patient received gentle debridement with a toothbrush. One tooth had a large cavity with moderate mobility and will likely require extraction in a hospital setting. A second application of Prevora was administered.

Fig. 5A

Before and after one Prevora treatment in palliative care
Before and after one Prevora treatment in palliative care. Pre-Prevora.

Fig. 5B

1 month after 1 Prevora treatment + SDF + GIC
1 month after 1 Prevora treatment + SDF + GIC

However, the family wishes to continue with non-invasive homecare with Prevora for now as they are concerned about the stress of the alternative care on the patient.


Oral dysbiosis, the primary cause of poor oral health, emerges with age, with chronic disorders such as Type 2 diabetes, Parkinson’s, Alzheimer’s, sarcopenia, multiple medication use (xerostomia), mood disorders and various forms of arthritis, which limit personal oral hygiene. It also results from a change in diet and immunity, as well as stress.

As an infection, OD is largely unaffected by restorative dental care and by standard preventive procedures using fluoride or mechanical debridement. In many cases, these procedures cannot be tolerated so a new, less invasive approach is needed.

Oral dysbiosis is a serious medical event. It contributes to several medical problems:

  • Type 2 diabetes: Reduced oral inflammation reduces HbA1Cs by 10%.1 Lower oral inflammation also significantly reduces the risk of complications from diabetes such as neuropathy, retinopathy and an early death.2
  • Hypertension: Oral inflammation is as significant to high blood pressure as age, gender, BMI, income and diabetes.3 OD doubles the risk of hypertension in otherwise healthy adults.4
  • Cardiovascular disease and stroke: Oral inflammation increases the odds of stroke by 4x.5 Lowered oral inflammation is significantly correlated with improved physical functioning during stroke rehabilitation6 and with reduced atherosclerosis.7
  • Depression: Chronic oral inflammation doubles the risk of mood disorders.8
  • Cognitive decline: Chronic oral inflammation significantly increases the chance and pace of progressing from Mild Cognitive Impairment to dementia.9
  • Sarcopenia (frailty): Poor oral health more than doubles the odds of becoming frail in the next year.10
  • Inflammation: Oral inflammation increases one measure of systemic inflammation (C-reactive protein) by 20%.11
  • Respiratory disease: Lower oral inflammation significantly reduces adverse respiratory events, hospitalization, frequency of exacerbations and deaths in adults with COPD.12,13

Prevora has been shown to be safe and effective in managing OD in randomized, controlled clinical trials of community dwelling adults, in observational studies, prospective studies and over 10 years of Real-World-Experience (RWE) in Canadian hygiene and dental clinics. In two adult studies accepted by regulatory authorities and involving over 1,100 medium to high-risk adults over one year’s treatment and observation, compared to placebo, Prevora reduced root caries by 41% (p<0.05) in vulnerable older adults without saliva,14 and reduced coronal caries by 70% (p<0.05) for very high risk adults affected by the social determinants of health (e.g. low income, no dental insurance, no regular dentist, 3 or more lesions at the start of the treatment plan).15 In terms of chronic oral inflammation, two studies involving high risk adults with unresponsive periodontitis, show Prevora to be safe and effective.16,17

The four case studies illustrate beneficial treatment of OD at a level not seen in other treatments and in patients who would otherwise have difficulty receiving or tolerating other procedures. In the case of the Alzheimer’s patient, the palliative patient and perhaps the Parkinson’s patient, regular invasive dental care is no longer a treatment option nor is it affordable or tolerable given the extent of oral morbidity and continued clinical risk. According to the clinical study data and the experience with Prevora by the first author over 8 years, this treatment effect is expected to continue over the long term. Periodic re-applications of Prevora should be scheduled using BOP levels and emerging caries as guides. The Prevora protocol stipulates a “booster” of Prevora every six months but clinical judgement on the treatment plan is required, particularly in patients at elevated risk of poor oral health.

For years, hygienists have seen a growing need for more effective preventive procedures for our seniors, those with complex needs, in long-term care and with those who cannot tolerate invasive care in their mouths. Prevora meets the needs of these patients. It is validated for preventing caries by randomized, controlled studies and has shown to have a significant benefit for unresponsive periodontitis. Perhaps most importantly, Prevora benefits adults without any other option for care.


J. Di Nardo is a clinical adviser to CHX Technologies which has developed Prevora. I. DeHaan and J. Stang have no conflict of interest.


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About the Author

Julie DiNardo is the founder and owner of Gleam Smile Centre, Hamilton, ON. She has practised as an independent hygienist since 2008.



Irene DeHaan is the founder and owner of iSmile Ottawa, a mobile hygiene service focused on seniors. Irene has practised independently for several years.



Julie Stang is the founder and owner of Connexions Dental Hygiene in Calgary, AB. She has practised independently for several years