Shisei Kubo

Clinical guidelines for treating caries in adults following a minimal intervention policy--evidence and consensus based report.

OBJECTIVES In 2002, FDI (World Dental Federation) published a policy advocating that caries be treated by minimal intervention (MI). This MI policy has been accepted worldwide and is taught in universities. But acceptance in general dental practice has been slower, especially in Japan where healthcare payment and practice favour drilling and filling. To help disseminate this MI policy into general practice, the Japanese Society of Conservative Dentistry developed an evidence-based clinical guideline for restoring carious permanent teeth in adult patients. METHODS The guideline was developed by a committee of nine university clinicians and a librarian. The committee selected the most frequent clinical questions in treating caries and used electronic databases to search and assess the best scientific evidence for each. Members then added their clinical experience and discussed to reach consensus on each question on treating caries with MI policy. Graded recommendations and guidance were made for each clinical question. The provisional guideline was strengthened after review and discussion with university researchers and general practitioners. RESULTS The guideline addresses the 16 most frequent clinical questions in treating adult caries, including restorative methods and how to tackle root caries. Recommendations for treatment using MI policy were developed using the best scientific evidence and consensus of experienced clinicians. CLINICAL SIGNIFICANCE The guideline offers a practical expert view of treating caries with the MI policy that incorporates the best scientific evidence, the latest techniques, the most preferable materials and the general consensus of expert clinicians.

Three-year clinical evaluation of a flowable and a hybrid resin composite in non-carious cervical lesions

OBJECTIVES This randomized controlled clinical trial evaluated the 3-year clinical performance of a hybrid (Clearfil AP-X; AP) and a flowable (Clearfil Flow FX; FX) resin composite in 98 non-carious cervical lesions. METHODS Twenty-two patients, 11 males and 11 females (mean age: 61.9 years, range: 29-78 years) regularly visiting the Nagasaki University Hospital, participated in the study. Each patient received both materials randomly. All restorations (48 restorations for AP and 50 restorations for FX) were placed in conjunction with an all-in-one system (Clearfil S(3) Bond) by one dentist. The restorations were blindly evaluated by two examiners at baseline, 6 months, 1, 2 and 3 years using modified USPHS criteria. The data were statistically analyzed using the Cochrans Q-test and Fishers exact test. RESULTS All the patients were examined at each recall. However, five restorations could not be evaluated at 3-year recall as two teeth had been extracted and three restorations had been lost. The only minor problem was the integrity of the enamel margin. The incidence and extent of marginal staining increased with time, but it was still superficial. Marginal staining occurred adjacent to 11 restorations for AP and 12 restorations for FX after 3 years. Neither lesion size nor depth had influence on marginal staining adjacent to each type of resin composite. There were no significant differences in the clinical performances between AP and FX for each variable. CONCLUSIONS Under the protocol used in this study, both types of resin composite in conjunction with S(3) Bond demonstrated an acceptable clinical performance up to 3 years.

Two-year clinical evaluation of one-step self-etch systems in non-carious cervical lesions

OBJECTIVES This randomized controlled clinical trial evaluated the 2-year clinical performance of S3 Bond (S3) and G-Bond (GB) in 108 non-carious cervical lesions. METHODS Twenty-three patients, 12 male and 11 female (mean age: 61.8 years, range: 30-79 years) regularly visiting the Nagasaki University Hospital of Medicine and Dentistry, participated in the study. Each patient received both materials randomly. All restorations (53 restorations for S3 and 55 restorations for GB) were placed by one dentist. The restorations were blindly evaluated by two examiners at baseline, 6 months, 1 and 2 years using modified USPHS criteria. The data were statistically analyzed using the Cochran Q test and Fishers exact test. RESULTS One restoration of each material was lost during 2 years. The only minor clinical problem was the integrity of the enamel margin. Slight marginal staining occurred adjacent to 11 restorations of both S3 and GB. There was no significant difference in the clinical performance between S3 and GB for each variable. CONCLUSIONS Under the protocol used in this study, S3 and GB have demonstrated an acceptable clinical performance up to 2 years.

Challenges to the clinical placement and evaluation of adhesively-bonded, cervical composite restorations

OBJECTIVES The incidence of non-carious cervical lesions (NCCLs) has been increasing. The clinical performance of resin composites in NCCLS was previously unsatisfactory due to their non-retentive forms and margins lying on dentin. In order to address this problem, a lot of effort has been put into developing new dentin adhesives and restorative techniques. This article discusses these challenges and the criteria used for evaluating clinical performance as they relate to clinical studies, especially long-term clinical trials. Polymerization contraction, thermal changes and occlusal forces generate debonding stresses at adhesive interfaces. METHODS In laboratory studies, we have investigated how these stresses can be relieved by various restorative techniques and how bond strength and durability can be enhanced. Lesion forms, restorative techniques, adhesives (adhesive strategies, bond strengths, bond durability, and the relationship between enamel and dentin bond strengths) were found to have a complex relationship with microleakage. With regard to some restorative techniques, only several short-term clinical studies were available. RESULTS Although in laboratory tests marginal sealing improved with a low-viscosity resin liner, an enamel bevel or prior enamel etching with phosphoric acid, clinical studies failed to detect significant effects associated with these techniques. Long-term clinical trials demonstrated that adhesive bonds continuously degraded in various ways, regardless of the adhesion strategy used. SIGNIFICANCE Early loss of restoration may no longer be the main clinical problem when reliable adhesives are properly used. Marginal discoloration increased over time and may become a more prominent reason for repair or replacement. Reliable and standardized criteria for the clinical evaluation of marginal discoloration should be established as soon as possible and they should be based on evidence and a policy of minimal intervention.

A pilot study to assess the morphology and progression of non-carious cervical lesions

OBJECTIVE This longitudinal pilot study aimed to morphologically and quantitatively investigate the progress of non-carious cervical lesions (NCCLs) by using swept-source optical coherence tomography (SS-OCT). METHODS The samples examined comprised sets of NCCL epoxy resin replicas obtained from 10 lesions in 6 patients who attended annual dental visits over 4 or 5 years. SS-OCT images of the replicas were analyzed in terms of the maximum depth (Dmax) and corresponding vertical width (VW) - using an image analyzer to estimate progression of the NCCLs over time. RESULTS It was found that differences between wedge- and saucer-shaped lesions were morphologically distinguished well by the OCT images. There were significant differences in dimensions among Dmax, VW and horizontal width (HW). HW was the largest and Dmax was the smallest. Although no significant differences in absolute values of annual progression rates were found among Dmax, VW and HW, the percentage increase in Dmax was significantly greater compared to VW and HW. The ratios of Dmax to corresponding VW ranged from 0.49 to 1.01 for the wedge-shaped lesions and from 0.13 to 0.44 for saucer-shaped lesions, respectively. CONCLUSIONS The dimensional analysis demonstrated notable progression with large variations. The wedge-shaped lesions appeared to show greater Dmax values compared to the saucer-shaped lesions. CLINICAL SIGNIFICANCE With respect to the depth, the wedge-shaped lesions may progress at a greater rate compared to the saucer-shaped lesions.

Root Caries Management: Evidence and Consensus Based Report

Root caries are becoming an increasingly common clinical problem, especially as aged-society. This report is based on the clinical practice guideline which offers a practical expert review of managing root caries with the best scientific evidence and the general consensus of expert clinicians. Root caries should be managed differently from coronal caries, and a shift of its strategy from “early-detection and early-treatment” to “early-detection and long-term management” is called for. Once the restorative treatment is chosen, it is often more advantageous to use glass-ionomer than resin composite. In addition, as we face a super-aged society now, in today’s dentistry setting, silver diammine fluoride (SDF) with high demineralization inhibitory effect is being re-evaluated as the “rescue material” (material for emergency cases) for root caries.