Evidence-based consensus for treating incipient enamel caries in adults by non-invasive methods: recommendations by GRADE guideline.

Remineralization treatment, which offers the advantage of being non-invasive, is increasingly being used as a minimal intervention treatment in managing incipient enamel caries. The aim of this review was to develop EBM guideline for optimized strategies for non-invasive treatment of incipient enamel caries. Japanese Society of Conservative Dentistry (JSCD) guideline committee formulated a Guideline for treating incipient enamel caries using the GRADE system, which is the global, mainstream standard for guideline development. The committee selected the most frequent clinical questions (CQs) in treating incipient enamel caries and identified clinically important outcomes in evaluating the efficacy of treatments. Using extensive electronic and manual searches, relevant randomized controlled trials and controlled clinical trials were identified. Based on evidence profiles produced by the committee, the panel discussed the effects, benefits and disadvantages of the selected treatments, as well as their cost effectiveness and feasibility, in order to achieve a consensus in treating incipient enamel caries non-invasively. A recommendation was made for each clinical question after voting by the panel members. Based on the evidence profile and panel discussions for each CQ, the experts strongly recommended application of topical fluoride to inhibit cavitation of incipient enamel caries, and to diminish white spot lesions.

Identification of the microbiota in carious dentin lesions using 16S rRNA gene sequencing.

While mutans streptococci have long been assumed to be the specific pathogen responsible for human dental caries, the concept of a complex dental caries-associated microbiota has received significant attention in recent years. Molecular analyses revealed the complexity of the microbiota with the predominance of Lactobacillus and Prevotella in carious dentine lesions. However, characterization of the dentin caries-associated microbiota has not been extensively explored in different ethnicities and races. In the present study, the bacterial communities in the carious dentin of Japanese subjects were analyzed comprehensively with molecular approaches using the16S rRNA gene. Carious dentin lesion samples were collected from 32 subjects aged 4-76 years, and the 16S rRNA genes, amplified from the extracted DNA with universal primers, were sequenced with a pyrosequencer. The bacterial composition was classified into clusters I, II, and III according to the relative abundance (high, middle, low) of Lactobacillus. The bacterial composition in cluster II was composed of relatively high proportions of Olsenella and Propionibacterium or subdominated by heterogeneous genera. The bacterial communities in cluster III were characterized by the predominance of Atopobium, Prevotella, or Propionibacterium with Streptococcus or Actinomyces. Some samples in clusters II and III, mainly related to Atopobium and Propionibacterium, were novel combinations of microbiota in carious dentin lesions and may be characteristic of the Japanese population. Clone library analysis revealed that Atopobium sp. HOT-416 and P. acidifaciens were specific species associated with dentinal caries among these genera in a Japanese population. We summarized the bacterial composition of dentinal carious lesions in a Japanese population using next-generation sequencing and found typical Japanese types with Atopobium or Propionibacterium predominating.

The usefulness of three-dimensional imaging in the diagnosis and treatment of clinically ambiguous gingival swelling.

We evaluated and treated a 54-year-old woman with gingival swelling. Conventional intraoral and panoramic radiography did not provide sufficient information for either determining the cause of gingival swelling or planning treatment of clinical symptoms. The 3D Accuitomo XYZ Slice View Tomograph (3DX) is a compact dental computed tomography device that allowed for accurate identification and optimal treatment of the causes of gingival swelling. At four years after treatment, 3DX radiographs showed no abnormalities in treated teeth or healing of surrounding structures. We conclude that high-resolution 3D images obtained with 3DX promise to be very effective for diagnosing oral diseases and determining effective treatment.

Long-term follow-up of composite resin restorations with self-etching adhesives.

OBJECTIVE: To test the hypothesis, derived from a previous short-term (7-day) assessment, that the absence of conventional pulp protection is not responsible for long-term pulp complications of composite resin restorations with self-etching adhesives. METHODS: All 150 patients who received the restorations with self-etching adhesives were recalled at least 2 years after the placement of restorations. Of the 47 patients (31%) who responded, 106 restorations aged from 2.2 to 6.5 years were examined for tooth sensitivity and pulp vitality regarding long-term pulp complications. The results were subjected to a multivariable logistic regression analysis with regard to cavity depth, provision of conventional pulp protection and short-term pulp complications. RESULTS: No positive cases were found in the assessment of tooth sensitivity. Four restorations (3.7%) made in deep cavities with conventional pulp protection resulted in pulpectomy due to inflammation, of which three cases presented short-term pulp complications. The 95% confidence intervals for the odds ratios estimated by the multivariable logistic regression analysis were (1.54, infinity) for cavity depth (1.50, infinity) for short-term pulp complications and (0.02, infinity) for conventional pulp protection. Namely, the last variable had no significant effect on long-term pulp complications and thus the hypothesis was verified. CONCLUSIONS: The absence of conventional pulp protection was not responsible for long-term pulp complications even in deep cavities with the use of self-etching adhesives. A deep cavity and the existence of short-term pulp complications were two critical predictors for the occurrence of long-term pulp complications.

Self-etching adhesives and postoperative sensitivity.

PURPOSE: To test the hypothesis that the prevention of postoperative sensitivity in resin-based composite restorations is better achieved with a self-etching/self-priming (SE/SP) dentin bonding system without lining than with an early generation total-etch (TE) bonding system. METHODS: Over a 4-year period, clinical follow-ups were conducted on patients who had received composite restorations. The depth of each cavity was categorized as being shallow, medium or deep, and an evaluation was made regarding the need for pulpal protection for each restoration. Three different self-etching/self-priming (SE/SP) adhesive systems were compared to three different total-etch (TE) adhesive systems. The incidences of postoperative sensitivity (IPS) were examined by a standardized procedure 1 week after placement of the restoration. Patients' ages varied between 16-83 years. RESULTS: The total number of restorations placed in vital teeth were 330 for 150 patients in the SE/SP group, and 126 for 70 patients in the TE group. Incidences of IPS in the total number of restorations stratified for depth were 14% in deep cavities, 6% in medium depth cavities and 5% in shallow cavities in the SE/SP group, and 35% in deep cavities, 16% in medium and 4% in shallow cavities in the TE group. Fisher's exact test showed the incidence of IPS was significantly higher in cases of deep (P< 0.05) and medium (P< 0.05) cavities. The test also revealed that in restorations placed with the SE/SP adhesive systems, the presence or absence of a protective liner or base made no significant difference in the IPS in medium and shallow cavities, while the use of such protective layers produced a significantly higher IPS (21%), compared with no protection (0%), in deep cavities (P< 0.05). The absence of protective liners or bases did not result in postoperative sensitivity in deep cavities, when the SE/SP dentin bonding systems were used.

Water absorption of poly(methyl methacrylate) containing 4-methacryloxyethyl trimellitic anhydride.

The amount of water absorption of poly(methyl methacrylate) (PMMA) containing 0, 1, 3 and 5 wt% of an adhesive monomer, 4-methacryloxyethyl trimellitic anhydride (4-META), was measured at 7 degrees C, 37 degrees C and 60 degrees C. After the water uptake reached equilibrium in specimens, they were desorbed to obtain a constant value and the absorption process was repeated. Mass changes in the second desorption were recorded for the storage temperatures of 37 degrees C and 60 degrees C. Multiple regression analyses were conducted on three independent variables, 4-META concentration, storage temperature and absorption-desorption cycle. A statistically significant relationship was found between the maximum water uptake and 4-META concentration, while there was no relationship between the maximum water uptake and diffusion coefficient obtained using the Fick's law. The negative relationship in the latter did not support the free space theory. The significant and positive relationship between the maximum water uptake and 4-META concentration demonstrates that water molecules diffuse through the formation of a hydrogen bond at polar sites. The maximum water uptake was not influenced by temperature, while the diffusion coefficient increased with the rise in temperature. The activation energy was 41-47 and 50-53 kJ/mol in the first and second absorption tests, respectively.