Root caries can only develop if exposed root surfaces are present. Prevention of root caries therefore starts with preventing gum recession.

Important for this is careful oral hygiene and compliance with the fluoride basic advice. The guideline on the prevention of root caries is intended for dentists and dental hygienists.

This advice for the prevention of root caries is intended for dentists and dental hygienists. The advice contains substantive aspects of the information and preventive actions that can be performed by the healthcare provider. The advice has been drawn up by the Advisory Board for the Prevention of Oral and Dental Diseases of the Ivoren Cross.

Contents:
1. Principles of the advice
2. Problem description
3. Primary prevention
4. Secondary prevention
5. Explanation of the proposed measures
6. Advice for people with overdentures and people who are no longer able to care for themselves
Literature
Tables 1 to 3

1. Principles of the advice
The advice is based on two principles. Firstly, the advice is based as much as possible on scientific information. Where possible, the recommendations are marked (A, B or C) that provides insight into the scientific weight of the advice.
– A advice: is based on at least one randomized controlled clinical trial as part of a body of literature of generally good quality and consistency, focusing on the specific recommendation.
– B advice: is based on the availability of well-conducted clinical research, but no randomized controlled clinical trials are available on the subject of recommendation.
– C advice: is based on evidence from relevant laboratory studies, expert committee reports or on opinions and/or clinical experience of respected authorities.
A second starting point was a prioritization of self-care over professional care if both forms of care were equally effective and efficient.

The advice has been given a format that distinguishes between primary and secondary prevention. Successive recommendations are given within this. The most effective measure or measures are paramount. These usually also have the best scientific substantiation. Subsequently, alternative measures are proposed, in case the first option fails. The follow-up recommendations will generally find less scientific support.

Finally, a number of special measures are indicated with regard to two special patient groups.

2. Problem description
As age progresses, the likelihood of gingival retraction increases, due to periodontal disease and periodontal treatments. As a result, tooth root surfaces previously covered by gingiva and bone are exposed to the oral environment, creating a risk of root caries.
The number of carious surfaces due to root caries is difficult to determine because the reason for restoration cannot be determined. However, it varies between 5 and about 14 % (Kalsbeek et al., 1998). There is also little epidemiological research in the Netherlands into the way in which root caries can be prevented. It has been shown that 72 percent of adults have one or more carious and/or restored root surfaces two years after periodontal treatment (Keltjens; 1988). In Sweden, root caries was found in 50 percent of adults two years after periodontal treatment despite extensive pre- and post-treatment by dentist and dental hygienist (Ravald and Birkhed, 1992).
The majority of new root caries was observed on the buccal surfaces, followed by the mesial, distal and lingual surfaces (Emilson et al., 1988). In the lower jaw root caries was mostly found buccally and in the upper jaw often palatal and proximal.

3. Primary prevention
Root caries can only develop if exposed root surfaces are present. Prevention of root caries therefore starts with the prevention of gingival recession. Important for this is careful oral hygiene and compliance with the basic fluoride advice. Dentists and dental hygienists must also prevent iatrogenic risks and damage as much as possible.
Furthermore, in principle, the possibilities for the prevention of root and crown caries are largely the same, because the etiology is similar. However, prevention of root caries should be even more intensive than for crown caries, given the lower resistance of the root surface to demineralization and the relatively high pH at which demineralization could occur. This applies to both the measures to be taken by the patient and the dentist.

4. Secondary prevention
If primary prevention offers insufficient protection, secondary preventive measures can be taken. These are subdivided into groups of advice, which it is preferable to go through in the order of presentation. One should only move on to the next group of recommendations if the previous group has not produced sufficient results. Specific measures are indicated for people with overdentures and people who are no longer able to care for themselves. When advising on the measures, the (financial) implications must in all cases be realized and made clear to the patient.

The first series of recommendations in secondary prevention are:

1. Promote careful oral hygiene with fluoride toothpaste (Nyvad and Fejerskov, 1986; Lynch and Bayson, 2001) (Grade A) and adherence to basic fluoride advice. Make sure that the risk areas are actually reached by the fluoride toothpaste.

2. If careful cleaning is not possible due to undercuts in the cavity, they should be carefully contoured (Billings et al., 1985) (Grade A)

3. Apply topical fluoride application after scaling and planing (Grade C)

4. Saliva secretion rate may be decreased (grade A). This should be measured and the cause of the reduced secretion rate should be traced. In this case, the practitioner should draw up a preventive treatment plan based on extra fluoride and saliva stimulation.

If the previous measures fail to achieve the desired result, you can proceed to:

5. Supplementing (self)care with daily (0.05% NaF=250ppm F) fluoride rinse (Wallace et al., 1993) (grade B)

6. Application of fluoride application with Duraphat (Keltkens, 1988) for locations not accessible to flushing fluid (grade B);

7. Dentin Adhesives (Grogono and Mayo, 1994) (Grade C)

If the above advice is not successful enough, you can proceed to:

8. Supplementing self-care with weekly rinsing with 0.12 or 0.2 % chlorhexidine (Grade C)

9. Soaking Proximal Cleaning Devices in 0.12 or 0.2 % Chlorhexidine (Grade C)

If the above advice is not successful enough, you can proceed to:

10. Chlorhexidine treatment with EC 40 or 1% gel (Grade C).

5. Explanation of proposed measures
Ad 1.
In the first instance, one should think of the quality and not the quantity of oral hygiene. It does not seem wise to have people who are at risk of caries due to receding gums brush their teeth more than twice a day, as this increases the risk of further receding gums.
Improving the quality of oral hygiene often means site-specific cleaning. The patient is often insufficiently aware of the fact that new risk areas for caries have been created by the receding gums, and he has insufficiently adapted his brushing habits to the new situation. The new exposed tooth tissue at the original site of the gingiva is insufficiently cleaned. Sometimes the shape of the brush is not suitable for reaching risk areas. A different toothbrush or an electric toothbrush can then help.

When proximal cleaning is required, the appropriate device should be selected. If cleaning proximally to prevent caries, fluoride toothpaste should be used. This can be done by not rinsing the mouth between brushing and proximal cleaning or by first applying toothpaste (with the finger) in the proximal space. It should be checked that these procedures are not too abrasive.

It may be that a patient's dexterity has decreased so much that the manual toothbrush can no longer be used effectively. The electric toothbrush can also offer a solution in that case. However, in some cases it is also possible to adjust the manual toothbrush.

Ad 3.
There is no research on the necessity or effect of applying a concentrated fluoride solution after scaling and root planing. Axelsson et al (1991) have shown the positive effect of scaling and root planing every 2 to 3 months, followed by professional cleaning with a fluoride-containing polishing paste. However, the control group received no treatment at all, so that no statement can be made about the isolated effect of the fluoride treatment.
However, there are arguments to suggest that applying fluoride is beneficial. During scaling and root planing, the outer fluoride-rich layer of the tooth will be damaged. Restoring this seems like a sensible thing to do. In addition, after scaling and root planing, a (pseudo)pocket can be reduced, exposing 'new' tooth material to the mouth. This new tooth material is sensitive to demineralization and must be protected. This can be done, for example, by the local application of fluoride.
One point to consider is whether scaling and root planning is always necessary. The dentist or dental hygienist should weigh this carefully. In addition, it may be considered to use Teflon instruments, which may reduce damage.

ad 4.
An unexpectedly changed caries picture is often an indication that the secretion rate of the saliva has decreased. To gain more certainty about this, it must be checked whether the basic fluoride advice is being followed. In addition, an anamnesis should be taken about any medication use (if so, which medication?), about any chronic and autoimmune disease and about any radiotherapy in the head and neck area.
Saliva secretion rates can be measured by collecting all the saliva that is produced for 5 minutes. The reference values are > 0.25 ml/min for unstimulated saliva and > 0.75 ml/min for stimulated saliva. If the saliva flow rate is too low, it is the task of the practitioner to detect the cause (or have it detected) and to draw up a preventive treatment plan.
If only the unstimulated saliva secretion is too low, the prevention consists of 4 fluoride moments per day (see ad 5) and stimulating the salivary flow by having them chew sugar-free chewing gum up to 5 times a day for a maximum of 5 minutes.
In addition, if stimulated salivary flow is reduced, additional fluoride applications may be considered with 1% neutral sodium fluoride gel at a frequency of 1x per month, 1x per week or 1x per 2 days depending on the severity
If the saliva flow can no longer be stimulated, saliva substitutes can be used.

Ad 5.
For additional individual fluoride measures, the Ivory Cross recommends in the Fluoride advice to increase the fluoride frequency to a maximum of four times a day, for example by means of:
1. Brush once or twice additionally with fluoride toothpaste
2. Using fluoride tablets
3. The use of fluoride flushing fluids
For the prevention of root caries, the use of fluoride rinsing fluids is recommended over the other measures, because there is research into the effect of these measures. Extra brushing is not recommended, because extra brushing can promote the receding of the gums and thus the development of risk areas. Effects of the use of fluoride tablets for the prevention of root caries have not been studied.

Add 7.
The possibilities of preventing root caries with dentin adhesives have only been explored in vitro. Grogono and Mayo (1994) applied Scotchbond Multi-Purpose to roots, after which the preparations were incubated in a demineralization system. After 70 days, no demineralization had occurred in the root surfaces.

AD 8, 9 and 10.
Today, there are many forms in which chlorhexidine is used in dentistry for the prevention of dental caries. However, there is little research on the effect of chlorhexidine on the prevention of root caries. There is one study on the effect of EC40 (Keltjens, 1988) and one study on the effect of weekly rinsing with 0.12 % chlorhexidine (Powell et al., 1999) on the incidence of root caries.
Research by Keltjens (randomized and controlled clinical trial) shows no significant difference between the effect of Duraphat and Duraphat mixed with Chlorhexidine (a prototype of EC40). Powell et al. (1999) were also unable to demonstrate in a randomized and controlled clinical experiment that weekly rinsing with 0.12% chlorhexidine protected against root caries.
Reduction of crown caries has been shown with EC40 (Fennis-Ie, 1998), with 1% chlorhexidine gel (Zickert et al., 1982; Gisselsson et al., 1988; Lindquist et al., 1989) with Cervitec as sealants (Bratthall et al., 1995; Joharji and Adenubi, 2001). Effect with EC40 and 1% chlorhexidine gel was only obtained in children with more than 10 6 mutans streptococci per ml saliva and high caries activity.
There are indications that these results in crown caries are not applicable to root caries. Van Strijp (1996) showed that although the number of mutans streptococci was strongly suppressed by chlorhexidine treatment, underlying dentin was not protected.

6. Advice for people with overdentures and people who are no longer able to care for themselves
When root caries occurs in people with overdentures and/or people who are no longer able to care for themselves, specific solutions must be sought.

People with overdentures
The pillar elements under a denture overdenture easily become carious and the periodontium quickly becomes inflamed. Due to the unfavorable position, these elements are not reached by saliva, no physiological cleaning takes place. An additional complication is that many of the patients concerned showed little interest in tooth preservation, at least in the past.
People with overdentures should be well informed about the complications of root caries. A prerequisite for prevention is optimal daily cleaning. In addition, a daily application of a fluoride gel or a chlorhexidine gel can take place. Assuming that the patient brushes with fluoride toothpaste, the choice will often fall on chlorhexidine. In addition, chlorhexidine also protects the periodontium, while this is hardly protected by the fluoride. The patient can apply the gel himself by placing a drop of gel in each pillar element recess in the overdenture. The overdenture is inserted and worn for 30 minutes. Then the prosthesis (and the mouth) can be rinsed. If the chlorhexidine application causes too many side effects (burning sensation or erosion of the gingiva), the application time can be shortened (Keltjens and van Os, 1994). The prosthesis itself should also be cleaned and should preferably not be worn at night. The soft tissues also need care.

People who are no longer able to take care of themselves
If someone is no longer capable of self-care, informal care or professional institutionalized care will have to take over this function. The best way to do this depends strongly on the individual situation. However, the dentist and dental hygienist must play an advisory and stimulating role.

Literature
Axelsson P, Lindhe J, Nystrom B. On the prevalence of caries and periodontal disease. Results of a 15-year longitudinal study in adults. J Clin Periodontol 1991;18:182-191

Billings RJ, Brown LR, Kaster AG. Clinical and microbiologic evaluation of contemporary treatment strategies for root surface dental caries. Gerodontics 1985;1:20-27

Bratthall D et al. A study into prevention of fissure caries using an antimicrobial varnish. Int Dent J 1995;45:245-254

DePaola PF. Caries in our aging population: what are we learning. In: Bowen WH and Tabak LA (eds). Cardiology for the nineties. Rochester, NY: University of Rochester Press, 1991

Emilson CG, Klock B, Sanford CB. Microbial flora associated with presence of root surface caries in periodontally treated patients. Scand J Dent Res 1988;96:40-49

Emilson CG, Ravald N, Birkhed D. Effects of a 12-month prophylactic program on selected oral bacterial populations on root surface with active and inactive carious lesions. Caries Res 1993;27:195-200

Fennis-Ie Y. Prevention and early diagnosis of occlusal caries. Dissertation KUNijmegen, 1998

Gisselsson H et al. Effect of professional flossing with chlorhexidine gel on approximal caries in 12- to 15-year-old schoolchildren. Caries Res 1988;22:187-192.

Grogono AL, Mayo JA. Prevention of root caries with dentin adhesives. Am J Dent 1994;7:89-90.

Jensen ME, Kohout F. The effect of a fluoridated dentifrice on root and coronal caries in an older adult population. J Am Dent Assoc 1988;117:829-832

Johansen E, Papas E, Fong W, Olsen TO.. Remineralization of carious lesions in elderly patients. Gerodontics 1987;3:47-50.

Joharji RM and Adenubi JO. Prevention of pit and fissure caries using an antimicrobial varnish: 9 month clinical evaluation. J Dent 2001;29:247-254.

Kalsbeek H, Truin GJ, van Rossum GMJM, van Rijkom HM, Poorterman JHG. Trends in caries prevalence in Dutch adults between 1983 and 1995. Caries Res. 1998;32:160-165

Kashani H et al. Effect of NaF-, SnF2-, and chlorhexidine-impregnated birch toothpicks on mutans streptococci and pH in approximal dental plaque. Acta Odontol Scand 1998;56:197-201.

Keltjens. HMAM. Microbiology and preventive treatment of root surface caries. Dissertation KUNijmegen, 1988.

Keltjens HMAM , van Os JH. Sustainable aftercare and treatment of complications. In: KalkW, Battistuzzi PGFCM, Käyser AF (eds). The Overdenture on natural pillar elements and implants. Diagnostics and treatment. Houten/Zaventem: Bohn Stafleu Van Loghum, 1994.

Leske G, Ripa L, Forte F, Varma A. Clinical trial of the effect of daily mouthrinsing on root caries. J Dent Res 1988;67:171

Lindquist B et al. Efcet of different caries preventive measures in children highly infected with mutans streptococci. Scand J Dent Res 1989;97:330-337.

Loveren C van. Prevention. Chapter 14. In Geriatric Dentistry issues of aging and oral health. Red Dr C. de Baat; prof.dr.W. Chalk. Bohn Stafleu Van Loghem. Houten/Diegem, 1999.

Lynch E, Baysan A. Reversal of primary root caries using a dentfrice with a high fluoride content. Caries Res 2001;35:60-64.

Nemes J, Banoczy J, Wierzbicka M, Rost M. Clinical study on the effcet of AmF/SnF2 on exposed root surfaces. J Clin Dent 1992; 3:51-53.

Nyvad B, Fejerskov O. Active root surface caries converted into inactive caries as a response to oral hygiene. Scand J Dent Res 1986;94:281-284

Powell LV, Persson RE, Kiyak HA, Hujoel Ph P. Caries prevention in a community-dwelling older population. Caries Res 1999:33:333-339.

Ravald N, Birkhed D. Prediction of root caries in periodontally treated patients maintained with different fluoride programs. Caries Res 1992;26:450-458

Retief DH, Wallace MC, Bradley EL. Incidence of root caries in an urban geriatric population on a 36-month preventive program. Caries Res 1990;24:423

Van Palenstein Helderman WH, van der Weijden GA. Oral hygiene. In: Van Loveren C and Van der Weijden GA (eds.) Preventive Dentistry. Houten: Bohn Stafleu Van Log-hum, 1996:157-186.

Van Strijp AJP. Bacterial colonization and degradation of dentine-an in situ study. Dissertation ACTA, 1996.

Ueberschar M, Gunay H. Root caries incidence with regular use of AmF/SnF2 mouth rinse. Dtsch Zahnartzl Z 1991;46:566-568.

Wallace MC et al. The 48-month increment of root caries in an urban population of older adults participating in a preventive dental program. J Public Health Dent 1993;53:133-137.

Van der Weijden GA, Timmerman MF, Reijerse E, Mantel MS, van der Velden U. The effectiveness of an electronic toothbrush in the removal of established plaque and treatment of gingivitis. J Clin Periodontol. 1995;22:179-82.

Zickert I et al. Effect of caries preventive measures in children highly infected with the bacterium Streptococcus mutans. Arch Oral Biol 1982;27:861-868.

Tables