Monographs in Oral Science最新文献

This chapter aims to discuss the way dental practitioners manage deep carious lesions (DCL) in routine practice and the barriers and incentives/facilitators to changes in accepted practice. In concert with the philosophy of minimal intervention dentistry, the concept of quaternary prevention (actions taken to prevent overtreatment and reduce harm to the patient) emerges in dentistry. This can be applied to carious tissue removal (CTR) in DCL given the risks associated with this procedure (high risk of pulp exposure, pulpal complications, tooth substance loss, and unsuccessful invasive, expensive outcomes). Recently conducted questionnaire surveys show that a gap exists between research findings and professional practices in relation to DCL management. It is, therefore, important to identify the barriers to the implementation of evidence-based dentistry into dental practices for the management of DCL in order to create appropriate corrective interventions to encourage practitioners in the use of selective CTR as a procedure.

Atraumatic restorative treatment (ART) is a method of managing dental caries based on 2 pillars: sealants for preventing carious lesions in pits and fissures, and restorations for cavitated dentine carious lesions. ART uses only hand instruments for opening/enlarging the cavity and for removing carious tissue. The amount of carious tissue that should be removed depends mainly on the cavity depth. In cavities of shallow and medium depth, carious tissue is removed up to firm dentine. In deep/very deep cavities, in which there is no sign of pulp exposure, pulp inflammation and/or history of spontaneous pain, some soft dentine can be left in the pulpal floor/wall with the aim of avoiding pulp exposure. The ART restorative method is indicated for treating single-surface cavities in primary and permanent teeth, and in multiple-surface cavities in primary teeth. Insufficient information is available to conclude on its use for treating multiple-surface cavities in permanent teeth.

Non-restorative cavity control (NRCC) is a 3-part treatment option for dentine cavities in the primary dentition, for root carious lesions and cavitated coronal smooth surface lesions. The first part is that the patient's oral hygiene procedure/habits improve and involve the exposed dentine. For this, it may be necessary to expose the cavity (second part) so that it is accessible for the toothbrush (the lesion exposure method). As long as the dentine carious lesion is diagnosed as active or there is increased risk that carious lesion activity will recur, it is advisable to support the treatment with a 38% silver diamine fluoride (SDF) or a 5% sodium fluoride (NaF) varnish therapy (third part). NRCC has advantages over traditional restorative therapy as it avoids the stress and fear initiation that often results from invasive restorative therapy. It avoids a futile or detrimental repeat restorative cycle when cavity outlines have to be designed in caries active areas and it increases awareness of people's own responsibility for oral health and the quality of the oral hygiene procedure. NRCC has been advocated, particularly in primary dentitions, for patients or parents/carers who are able to accept responsibility for the disease and commit to remedial action including diet modification and regular, frequent toothbrushing with a fluoride toothpaste. It should not be used when immediate invasive action is required such as in the case of pain, infection, or sepsis, or where there is no readiness to change behaviours that have led to the development of the disease in the first place. Professionals who choose NRCC commit themselves to being critical regarding their educational qualities and to commence a cycle of quality improvement.

One of the most conservative ways to retain tooth structure, preserve pulpal health, and avoid invasive treatment is to simply completely seal established carious lesions. A tight seal to isolate the biofilm and arrest the lesion can be successfully achieved using a sealant material such as resin or glass-ionomer for non-cavitated lesions, a restorative material for cavitated lesions, or, for primary teeth, preformed stainless-steel crowns. This chapter focuses on sealants and restorative materials. Sealant materials are a viable treatment option for controlling non-cavitated lesions in occlusal and proximal surfaces where there is no significant breach in the surface integrity of the tooth, even if the lesion extends into dentine. Resin infiltration can also be used to manage proximal non-cavitated lesions. Even when the exact depth of lesion that can be sealed has not been established, evidence supports sealing shallow and moderate deep lesions into dentine. For cavitated lesions, sealing lesions without carious tissue removal might be an option when removal of tooth tissue is not required to provide a hard periphery around the lesion/cavity margin (to enhance bonding or to increase cavity depth for enough restorative material to be placed to last). There is little evidence for placing a restorative material over cavitated carious lesions without tissue removal or preparation. However, where there is a significant breach in the surface integrity of the tooth but there is still enough sound tooth tissue to provide bonding for an adhesive restoration, sealing in carious tissue might still be an option.

Patients' susceptibility to coronal and root caries (RC) is modulated by a range of biological, environmental, social, psychological, and behavior-related factors. These factors, considered either in isolation or combined into specific models, contribute to the overall patient susceptibility/risk of new lesion occurrence and/or of existing lesion progression, allowing the oral healthcare team to define specific and individualized preventive and curative regimens. Various caries susceptibility/risk assessment (CRA) protocols/models have been developed to assist the oral healthcare practitioner/team in a logical systematic approach to synthesize information about the caries disease process with its multifactorial etiology. These protocols/models consider caries susceptibility/risk in general without any specific localization of the caries process; none of them specifically consider the risk of developing carious lesions in root surfaces. This chapter aims to discuss CRA related to RC lesions in terms of prediction of both the occurrence of new RC lesions and of continuing progression of existing lesions.

The prevalence of root caries among the elderly is increasing. The lesion shape can vary considerably from a broad shallow saucer-shape to a deeper defined cavity. The variety of shapes poses a series of complications when considering restorative management. This is accompanied with a paucity of clinical evidence on treatment techniques and clinical outcomes. The current philosophy centered on conservative management of root caries will most likely provide patients with the greatest chance of maintaining their teeth. When a lesion can be effectively cleaned in conjunction with a high fluoride content toothpaste and other remineralizing agents, this should be the treatment of choice. For lesions that are cavitated and cannot be effectively cleaned, the initial management should be to apply remineralizing agents for a period to "harden" lesion margins thus potentially reducing the prepared cavity and restoration size, as well as providing a better-defined tooth-restoration margin for finishing. Material selection is either a glass ionomer cement (conventional or resin-modified) or resin-based material. Frequently, the restoration site is easily contaminated; hence, glass ionomer cement is an ideal material. However, for saliva-deficient patients, resin composite or a combination of resin composite and resin-modified glass ionomer adhesive allows for a highly polished, easily cleansable restoration surface that may reduce the potential for further caries initiation. The current evidence base for the restoration of root caries is poor.

Root caries lesions (RCLs) are highly prevalent in elderly and can negatively impact the quality of life. Therefore, preventive therapies should be applied to control or to arrest RCLs. This chapter will discuss the application of fluoride, a conventional preventive therapy, to control RCLs. Among the self-applied products, there is strong evidence that 5,000 ppm F toothpaste is more effective in arresting RCLs (by increasing hardness) and in preventing new lesions (PF of 51%) compared to 1,100-1,450 ppm F toothpastes, in 6-month clinical trials. With regard to professional fluoride applications, 5% NaF varnish (4 times/year) and 38% silver diamine fluoride solution (1 time/year) have been tested in clinical trials with a follow-up of 3 years. Five percent NaF varnish and 38% silver diamine fluoride have been shown to prevent the emergence of new RCLs in 64 and 71%, respectively. The professional fluoride application is often combined with the daily use of 5,000 ppm F toothpaste. However, there is a gap in the knowledge about the benefit (cost-effectiveness) and the optimal use of the combinations of fluoride products in the control of RCLs.

Following gingival recession, which increases with age, the root surface becomes exposed, creating new environments for microbial colonization and biofilm formation. The formation of root surface biofilms is influenced by the availability and composition of saliva and gingival crevicular fluid; they provide components for the conditioning film (acquired root surface pellicle) and also act as a source of nutrients. The early bacterial colonizers of the root surface are similar to those found on the enamel, and Gram-positive species such as Streptococcus sanguinis, S. oralis, S. mitis, and Actinomyces species predominate. The root surface has a lower mineral and higher organic content than enamel, and so is more vulnerable to demineralization. The characterization of the microbiota associated with root surface lesions is still ongoing. Traditional culture-based studies have implicated species such as mutans streptococci, lactobacilli, bifidobacteria, and Actinomyces species, while molecular-based studies have provided evidence for a more complex microbiota with many Gram-negative and anaerobic bacteria being detected in addition to the more conventional cariogenic organisms. Ecological concepts have been applied to explain the microbial etiology of root caries. The acidic environment generated from the fermentation of dietary sugars selects saccharolytic bacteria that can preferentially grow and metabolize under low pH conditions, and then proteolytic Gram-negative species are selected when the dentin is exposed and collagen and other proteins become accessible to be catabolized. These species act in concert to degrade the inorganic and organic components of the dental tissues.

Population aging and the concomitant reduction in tooth loss will have a profound effect on dentistry. In particular, an increase in the prevalence of root caries can be expected. Root caries is not evenly distributed across the population and identification of high-risk groups or individuals would facilitate targeted prevention strategies. Unfortunately, the lack of consensus in the literature on the diagnosis and measurement of root caries makes comparison of studies extremely challenging. At present, we do not have an adequately validated risk assessment tool for root caries. Future research should focus resources on investigating risk indicators, which have been found to be significant in past studies and on externally validating previously described risk models.

As the thick biofilm in the presence of fermentable carbohydrates is the main etiological factor of dental caries, the frequent and systematic removal of this colony by means of an effective biofilm control should result in the prevention of caries lesions or in the arrest of the local carious process. However, the role of biofilm control in the management of dental caries has been questioned. This chapter will discuss the biofilm control and oral hygiene practices on root surfaces. Laboratory and clinical studies describing the effect of biofilm control and oral hygiene practices on the arrestment of root carious lesions are described. Epidemiological surveys evaluating the association between oral hygiene and root caries are discussed. Finally, some aspects on chemical biofilm control are also presented.