A randomized clinical trial on the sealing of occlusal carious lesions: 3–4-year results

Abstract This randomized clinical trial aimed to assess the efficacy of sealing occlusal carious lesions in permanent teeth. The sample consisted of 54 occlusal carious lesions in permanent molars and premolars of 49 patients aged 8–43 years (median: 19 years). The inclusion criteria comprised the presence of a cavity with no access allowing biofilm control. The maximum depth of the lesion was the middle third of the dentin thickness, as assessed by bitewing radiography. The teeth were randomly assigned to sealant treatment (n = 28) or restorative treatment (n = 26). Clinical and radiographic examinations were performed after 1 year and after 3–4 years. The outcomes depended on the clinical performance of the sealant/restoration and the control of caries progression observed radiographically. Survival analysis was performed to assess success rates. Over the 3-4 years of monitoring, 2 sealants were totally lost, 1 needed repair, and 1 showed caries progression, totaling 4 failures in the sealant group. In the restoration group, 1 failure was observed (in need of repair). The success rates were 76% and 94% in the sealant and the restoration groups, respectively (p > 0.05). The sealing of occlusal carious lesions in permanent teeth succeeded in controlling caries over a 3–4-year period. However, sealed carious lesions require patient compliance in attending regular follow-ups to control the occurrence of clinical failures of the sealants

Differences between normal and demineralized dentine pretreated with silver fluoride and potassium iodide after an in vitro challenge by Streptococcus mutans

The document attached has been archived with permission from the Australian Dental Association (8 March 2008). An external link to the publisher’s copy is included.Background: The application of diamine silver fluoride (Ag(NH3)2F) and potassium iodide (KI) to demineralized dentine has been shown to inhibit the growth of Streptococcus mutans. The purpose of this study was to observe the differences between demineralized and non-demineralized dentine treated with AgF/KI. Methods: Thirty-five dentine discs were bonded to the bases of 5mL polycarbonate screw top vials which were filled with nutrient medium, sterilized and placed into the overflow from a continuous culture of S. mutans. Samples were divided as follows: 10 samples of demineralized dentine; 10 samples of demineralized dentine treated with AgF/KI; 5 samples of non-demineralized dentine; and 10 samples of non-demineralized dentine treated with AgF/KI. Following two weeks connected to the Chemostat, an electron probe microanalysis (EPMA) of percentage weights and penetration depths of calcium, phosphorous silver and fluoride was conducted. Bacterial growth was monitored by taking optical density readings of the growth medium in each vial and outer surfaces of the specimens were examined by scanning electron microscopy (SEM). Results: AgF/KI treatment of demineralized and non-demineralized dentine prevented biofilm formation and reduced further demineralization by S. mutans. AgF/KI treatment of demineralized dentine was more effective in reducing dentine breakdown and the growth of S. mutans. Significantly higher levels of silver and fluoride were deposited within demineralized dentine. Conclusions: A topical treatment with AgF/KI on dentine reduced in vitro caries development and inhibited surface biofilm formation. Reduction of in vitro caries development and viability of S. mutans was more pronounced on the dentine samples that had been demineralized prior to the application of AgF/KI.GM Knight, JM McIntyre, GG Craig, Mulyani, PS Zilm and NJ Gull

Pit and fissure sealants in dental public health – application criteria and general policy in Finland

<p>Abstract</p> <p>Background</p> <p>Pit and fissure sealants (sealants) are widely used as a non-operative preventive method in public dental health in Finland. Most children under 19 years of age attend the community-organized dental health services free of charge. The aims of this study were to find out to what extent sealants were applied, what the attitudes of dental professionals towards sealant application were, and whether any existing sealant policies could be detected among the health centres or among the respondents in general. The study evaluated changes that had taken place in the policies used during a ten year period (1991–2001).</p> <p>Methods</p> <p>A questionnaire was mailed to each chief dental officer (CDO) of the 265 public dental health centres in Finland, and to a group of general dentists (GDP) applying sealants in these health centres, giving a total of 434 questionnaires with 22 questions. The response rate was 80% (N = 342).</p> <p>Results</p> <p>A majority of the respondents reported to application of sealants on a systematic basis for children with increased caries risk. The criteria for applying sealants and the actual strategies seemed to vary locally between the dentists within the health centres and between the health centres nationwide. The majority of respondents believed sealants had short- and long-term effects. The overall use of sealants decreased towards the end of the ten year period. The health centres (N = 28) choosing criteria to seal over detected or suspected enamel caries lesion had a DMFT value of 1.0 (SD ± 0.49) at age 12 (year 2000) compared to a value of 1.2 (SD ± 0.47) for those health centres (N = 177) applying sealants by alternative criteria (t-test, p < 0.05).</p> <p>Conclusion</p> <p>There seems to be a need for defined guidelines for sealant application criteria and policy both locally and nationwide. Occlusal caries management may be improved by shifting the sealant policy from the traditional approach of prevention to interception, i.e. applying the sealants over detected or suspected enamel caries lesions instead of sealing sound teeth.</p

The effect of silver fluoride and potassium iodide on the bond strength of auto cure glass ionomer cement to dentine

The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.Background: Diamine silver fluoride (Ag(NH3)2F), referred to as AgF, has been shown to reduce the incidence of caries in primary dentitions. The clinical application of this material has been limited by staining associated with both teeth and restorative materials. The application of potassium iodide (KI) after AgF eliminates stain formation. There is a lack of information as to how the addition of AgF followed by KI may affect the bond strength to dentine. The purpose of this study was to compare the bond strengths of auto cure glass ionomer cement to dentine surfaces that had been treated with AgF and KI and without treatment. Methods: Ten recently extracted human third molars were embedded into methyl methacrylate resin and sliced to form a square block of exposed dentine surfaces. Each of the four surfaces were treated by one of the following procedures: (a) etching with 37 per cent phosphoric acid; (b) applying GC dentine conditioner; (c) etching, followed by application of AgF/KI then washing off the precipitate and air drying; and (d) etching, applying AgF/KI and air drying the reaction products on the surface. Fuji VII auto cure glass ionomer cement was bonded onto each sample and fracture tested. Results: The dentine samples treated with AgF/KI followed by washing away the precipitate and air drying had bond strengths (2.83MPa) not significantly different from samples that had been conditioned (2.40MPa). Samples where the AgF/KI precipitate had been air dried onto the dentine surface had significantly lower bond strengths (1.49MPa) than the washed samples. Samples that were etched had significantly lower bond strengths (1.91MPa) than the conditioned samples. Conclusions: This study found that the application of AgF/KI to etched dentine samples followed by washing off the precipitate, created bond strengths that were not significantly different to conditioned samples. Leaving the AgF/KI precipitate on the dentine surface significantly reduced the bond strength of auto cured glass ionomer cement to dentine. Washing away the reaction products and air drying is recommended as the clinical protocol for using AgF and KI on dentine surfaces prior to application of an auto cure glass ionomer cement.GM Knight, JM McIntyre, Mulyan

An in vitro model to measure the effect of a silver fluoride and potassium iodide treatment on the permeability of demineralized dentine to Streptococcus mutans

The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.Background: Diamine silver fluoride (Ag(NH3)2F), referred to as AgF, has been used to reduce the incidence of caries in primary dentitions but has been limited by the associated staining of both teeth and restorative materials. The application of potassium iodide (KI), following AgF prevents staining but its effects on the ability of AgF to reduce caries are not known. The aim of this study was to develop an in vitro model that would provide an indication of the permeability of demineralized dentine to Streptococcus mutans after treatment of the dentine with AgF followed by KI. Methods: Forty dentine discs were bonded to the base of forty 5mL polycarbonate screw top vials (that had had their bases removed), filled with nutrient medium, sterilized and placed into a continuous culture of S. mutans. Samples were divided into four groups as follows: 10 samples of demineralized dentine as a control, 10 samples of demineralized dentine treated with AgF/KI, 10 samples of demineralized dentine treated with KI and 10 samples of demineralized dentine treated with AgF. After two weeks the optical density of the growth medium chambers was measured to determine bacterial penetration and growth. Cultures were plated out to determine migration through the discs by S. mutans. Results: S. mutans migrated through all dentine discs. However, the samples treated with AgF and AgF/KI had significantly lower optical densities than the corresponding controls. The range of optical densities was least amongst demineralized samples treated with AgF/KI. Conclusions: Under the conditions of this study, treatment of demineralized dentine discs with AgF followed by KI allowed the penetration of S. mutans. Based on optical density measurements, the treatment resulted in significantly fewer microorganisms being present subjacent to the discs treated with AgF and KI than the control discs at the end of the experimental period.GM Knight, JM McIntyre, GG Craig, Mulyani, PS Zilm and NJ Gull

Two decades of ART: improving on success through further research

Since the introduction of the Atraumatic Restorative Treatment (ART) approach over twenty years ago, more than 190 research publications have appeared. The last research agenda defining research priorities for ART was published in 1999. The objective of the present work was to review existing research in the context of future research priorities for ART. MATERIAL AND METHODS: An internet survey was conducted amongst those who had published on ART or were known to be working on the ART approach, to solicit their views as to areas of future ART research. Three broad categories were defined, namely: 1. Basic and laboratory research; 2. Clinical research, and, 3. Community, Public Health, Health Services Research. RESULTS: A 31% response rate was achieved. The study identified a number of new areas of research as well as areas where additional research is required. These are expressed as recommendations for future ART research. CONCLUSIONS: The ART approach is based on a robust, reliable and ever-growing evidence base concerning its clinical applications which indicates that it is a reliable and quality treatment approach. In common with all other oral health care procedures, targeted applied research is required to improve the oral health care offered

Systematic reviews, systematic error and the acquisition of clinical knowledge

<p>Abstract</p> <p>Background</p> <p>Since its inception, evidence-based medicine and its application through systematic reviews, has been widely accepted. However, it has also been strongly criticised and resisted by some academic groups and clinicians. One of the main criticisms of evidence-based medicine is that it appears to claim to have unique access to absolute scientific truth and thus devalues and replaces other types of knowledge sources.</p> <p>Discussion</p> <p>The various types of clinical knowledge sources are categorised on the basis of Kant's categories of knowledge acquisition, as being either 'analytic' or 'synthetic'. It is shown that these categories do not act in opposition but rather, depend upon each other. The unity of analysis and synthesis in knowledge acquisition is demonstrated during the process of systematic reviewing of clinical trials. Systematic reviews constitute comprehensive synthesis of clinical knowledge but depend upon plausible, analytical hypothesis development for the trials reviewed. The dangers of systematic error regarding the internal validity of acquired knowledge are highlighted on the basis of empirical evidence. It has been shown that the systematic review process reduces systematic error, thus ensuring high internal validity. It is argued that this process does not exclude other types of knowledge sources. Instead, amongst these other types it functions as an integrated element during the acquisition of clinical knowledge.</p> <p>Conclusions</p> <p>The acquisition of clinical knowledge is based on interaction between analysis and synthesis. Systematic reviews provide the highest form of synthetic knowledge acquisition in terms of achieving internal validity of results. In that capacity it informs the analytic knowledge of the clinician but does not replace it.</p