Efecto de los revestimientos en la microfiltración de resina compuesta después de la eliminación selectiva de lesiones cariosas. Un estudio experimental

This study aimed to systematically review the literature regarding the risk of selective removal-in comparison with stepwise and nonselective removal-of carious tissue in permanent teeth. Controlled clinical trials and cohort studies involving patients with dental caries in permanent teeth were included. Databases used were PubMed, Embase, and Scopus. The test group should be composed of patients undergoing selective removal of carious tissues, and the control group should comprise patients undergoing nonselective removal and/or stepwise removal of carious tissue. Laboratory tests, studies on primary teeth, and studies that used temporary restorations were excluded, as were literature reviews. The primary outcome was overall success of maintaining pulpal health (both clinically and radiographically). Quality of the restoration, pulp exposure, dentin deposition, and microbiological examination were also assessed. A meta-analysis, using the pooled risk ratio (RR) and its 95% confidence interval (CI), was performed to assess the success of maintaining pulpal health, using the different control treatments as a subgroup analysis. A total of 2333 articles were retrieved, of which 10 were included in the systematic review and four in the meta-analysis. In the qualitative evaluation, the control groups presented a higher risk of pulp exposure in relation to the selective removal. In the meta-analysis, the selective carious tissue removal showed significantly higher overall success (RR, 95% CI 1.11, 1.02-1.21). The selective carious tissue removal presented higher success of maintaining pulpal health. In permanent teeth, selective carious tissue removal should be performed, as this technique results in lower numbers of pulp complications, such as pulp exposure, as compared with nonselective removal.

To evaluate the effect of selective or nonselective carious tissue removal and the use of a resin-modified glass ionomer (RMGIC) liner under bulk fill resin composite restoration on the stress at the pulp chamber, the elastic moduli of hard, firm, soft and intact dentin were calculated using nanoindentation. Post-gel shrinkage of the bulk fill resin composite and RMGIC were determined using the strain-gauge method. Six finite element models were created by using digital radiography with the combination of two study factors: a) carious tissue removal: selective removal or nonselective removal of carious tissue, and b) use of RMGIC liner: with or without 1.0 mm of RMGIC liner. The modified von Mises stresses (mvm) (MPa) were extracted on the nodes of the internal wall of the pulp ceiling chamber at 100 N occlusal loading. Data were analyzed descriptively and recorded quantitively. Both study factors influenced the stress distribution. The mvm stress during the restorative procedure was higher for nonselective carious tissue removal without RMGIC (25.9 MPa) and lower for selective carious tissue removal associated with RMGIC (13.5 MPa). The dentin elastic modulus increased from soft carious (3.6 ± 0.3 MPa) to firm carious (5.2 ± 1.0 MPa) to hard carious (10.9 ± 1.2 MPa) to intact dentin (22.7 ± 3.0 MPa). Molars with carious lesions showed high mvm stress at the pulp ceiling (89.6 MPa) and at fragilized coronal structure remaining. Selective carious tissue removal followed by restoration using a Vitrebond liner and Tetric N-Ceram Bulk fill reduced the stress at the pulp chamber ceiling.

Statement of the Problem: A rise in pH and the presence of calcium ions play an important role in prevention or management of external root resorption.Purpose: This study assessed the long-term pH alterations in the periradicular area following the application of calcium hydroxide (CH) and mineraltrioxide aggregate (MTA) intracanal medicaments.Materials and Method: This in vitro, experimental study evaluated 45 single-canal extracted human teeth. After decoronation and root canal instrumentation,defects (3×3×1mm) were created in the middle third of the roots. Following smear layer removal, the root surface (except for the defect)was sealed with nail varnish. Five teeth served as negative controls and were filled with distilled water. The remaining 40 teeth wererandomly divided into two groups (n=20) for application of MTA and CH as intr-acanal medicaments. Periapical radiographs were obtained toensure optimal quality of obturation. After coronal sealing with glass ionomer, the teeth were incubated at 37°C, and their pH was measured at1 and 2 weeks, and 1 and 3 months, using a pH-meter. Data were analyzed using one-way ANOVA, Tukey’s test and Bonferroni adjustment.Results: The mean pH was significantly higher in CH group at 1 and 2 weeks (p< 0.01) but no difference was noted at 1 and 3 months (p= 0.52).The mean pH in both groups was significantly higher at 2 weeks compared with other time points (p< 0.05).Conclusion: CH may be preferred for use in the first weeks following the initiation of root resorption to provide a high pH. MTA can be later appliedto maintain the high pH for a longer period of time without the need for medicament exchange.

Background: It is common to replace amalgam with composite resins for different reasons. Changes in the dentin substrate after amalgam restorations might affect the bond strength between composite resin and dentin. This study evaluated the microtensile bond strength of composite resin to discolored dentin following amalgam replacement with universal adhesives. Methods: In this in vitro study, thirty-two sound human premolar teeth were collected. After preparing classic class I amalgam cavities measuring 2 mm in depth, 3 mm mesiodistally, and 2.4 mm buccolingually, half of the samples were randomly selected and restored with high-copper amalgam and underwent a thermocycling procedure (5000 cycles). They were stored at 37 ºC and 100% humidity for six months to form amalgam corrosion products. After removing the amalgam, each half was divided into four subgroups based on adhesive type (G-Premio Bond/All-Bond Universal) and bonding technique (self-etch/etch-and-rinse). Then, all samples were restored with composite resin. The microtensile bond strength was calculated, and data analysis was conducted using SPSS 25 and t-tests. Results: The bond strength values in the amalgam-affected subgroups were significantly (P&lt;0.05) lower than normal dentin. In all groups, the bond strength of the All-Bond Universal was higher than that of the G-Premio Bond. However, the bond strength in the etch-and-rinse technique in normal dentin was significantly (P&lt;0.05) higher than the self-etch technique. The bond strength in the amalgam-affected dentin subgroups with the All-Bond Universal was comparable to the bond strength of this adhesive to normal dentin with the self-etch technique. Conclusion: All-Bond Universal is suggested for both self-etch and etch-and-rinse techniques in amalgam replacement with composite resin. However, the self-etch technique is recommended if the G-Premio Bond is used.

To assess the efficacy of treatment using a minimally invasive approach (selective removal of carious tissue, restoration and preventive strategies) in immature permanent molars with MIH. A total of 281 patients, aged 6-8years, with carious lesions (ICDAS 5-6), severe MIH, and incomplete root formation (one tooth/patient) were included. After clinical and radiographic examinations, selective carious tissue removal was performed, and the teeth received interim restoration for 6months and were then restored with composite resin. Clinical and radiographic follow-up was undertaken, 6, 12, 18, and 24months. A protocol of preventive oral care measures was established and repeated at each follow-up, including diet counselling, oral hygiene instruction, dental plaque control, and topical application of fluoride varnish containing CPP-ACP. All clinical procedures and evaluations were done by a single operator. Clinical and radiographic success was observed 24months after treatment in 96.8% of the cases. Failures were due to enamel fracture at restoration margins, resulting in pulpitis and absence of apex closure. Selective removal of carious tissue, interim, and subsequently definitive restoration, combined with home and professional preventive measures, maintained marginal integrity of restorations in immature permanent molars with severe MIH, confirmed by pulp vitality and occurrence of apexogenesis.

The purpose of this study was to determine the relationship between mechanical properties and bond durability of short fiber-reinforced resin composite with universal adhesive. As controls, micro-hybrid and nano-hybrid resin composites were tested. The universal adhesives used were Scotchbond Universal, Adhese Universal, and G-Premio Bond. The fracture toughness and flexural properties of resin composites, and shear bond strength and shear fatigue strength of universal adhesive with resin composite using both total-etch and self-etch modes were determined. In the results, short fiber-reinforced resin composite showed significantly higher fracture toughness than did micro-hybrid and nano-hybrid resin composites. The flexural strength and modulus of short fiber-reinforced and nano-hybrid resin composites were significantly lower than were those of micro-hybrid resin composites. Regardless of etching mode, the shear bond strength of universal adhesives with short fiber-reinforced resin composite did not show any significant differences from micro-hybrid and nano-hybrid resin composites. The shear fatigue strength of universal adhesives with short fiber-reinforced resin composite and micro-hybrid resin composites were significantly higher than that of nano-hybrid resin composites. The results of this study suggest that the mechanical properties of short fiber-reinforced resin composite improve their bond durability with universal adhesive.

This study aimed to evaluate the clinical efficacy of restorations after selective removal of carious tissue (SRCT) in permanent teeth. A randomized, controlled, and blinded clinical trial was conducted on 74 teeth to compare SRCT with two types of non-selective removal (nSRCT), which served as control groups. For medium-depth lesions (D2) that reached the middle third of the dentin, SRCT was compared with non-selective removal to hard dentine (nSRCT-HD). For deep lesions (D3) extending to the inner third of the dentin, SRCT was compared with stepwise removal of carious tissue (StRCT). Outcomes included pulp sensitivity and restoration quality, assessed using FDI Functional Property criteria. Adjusted analyses were performed using Poisson regression with robust variance to assess the risk ratio (RR) and its respective 95% confidence interval. A total of 62, 50, and 39 teeth were followed at 6, 12, and 18 months, respectively. Three pulp sensitivity failures occurred at 6 months (2 nSRCT, 1 SRCT), with no additional failures at 12 and 18 months. Regarding quality of restoration, no failure was observed and there was not significant difference between groups up to the 18-month period. SRCT was clinically effective in both mid-depth (D2) and deep (D3) lesions, addressing pulp sensitivity and restoration quality. In D3 lesions, it minimized the risk of pulp exposure while preserving dentin integrity, while in D2 lesions, it preserved tooth structure without compromising restoration performance. SRCT is a less invasive strategy, preserves more dental tissue and presents satisfactory results in relation to the preservation of pulp sensitivity and quality of restorations.

IntroductionMolar incisor hypomineralisation (MIH) is a qualitative defect of enamel development that occurs in the mineralisation phase. MIH affects one or more permanent molars and, occasionally, permanent incisors. The aim...

This study evaluated the effect of three methods of glass fiber insertion on stress distribution pattern and cusp movement of the root-filled maxillary premolars using finite element method (FEM) analysis. A three-dimensional (3 D) FEM model of a sound upper premolar tooth and four models of root-filled upper premolars with mesiocclusodistal (MOD) cavities were molded and restored with: (1) Composite resin only (NF); (2) Composite resin along with a ribbon of glass fiber placed in the occlusal third (OF); (3) Composite resin along with a ribbon of glass fiber placed circumferentially in the cervical third (CF), and (4) Composite resin along with occlusal and circumferential fibers (OCF). A static vertical load was applied to calculate the stress distributions. Structural analysis program by Solidworks were used for FEM analysis. Von-Mises stress values and cusp movements induced by occlusal loading were evaluated. Maximum Von-Mises stress of enamel occurred in sound tooth, followed by NF, CF, OF and OCF. Maximum Von-Mises stress of dentin occurred in sound tooth, followed by OF, OCF, CF and NF. Stress distribution patterns of OF and OCF were similar. Maximum overall stress values were concentrated in NF. Although stress distribution patterns of NF and CF were found as similar, CF showed lower stress values. Palatal cusp movement was more than buccal cusp in all of the models. The results of our study indicated that while the circumferential fiber had little effect on overall stress concentration, it provided a more favorable stress distribution pattern in cervical region. The occlusal fiber reduced the average stress in the entire structure but did not reduce cuspal movement. Incorporating glass fiber in composite restorations may alter the stress state within the structure depending on fiber position.

Aim: The aim of the study was to evaluate the effect of surface treatments on the repair ‎shear bond strength of aged ORMOCER resin composite. Materials and Methods: 12 discs ‎of ORMOCER based resin composite were divided into 6 groups (n = 2 discs/group) as per ‎the surface treatments performed as follows: 1-Medium grit diamond Bur+Universal ‎Adhesive. 2-Fine grit diamond Bur + Universal adhesive. 3-Air abrasion+ Universal ‎adhesive. 4-Air abrasion+ Silane+ Universal adhesive. 5-Etchant + Universal adhesive. 6-‎Etchant + Silane + Universal adhesive. Each disc received five micro-cylinders of flowable ‎nanohybrid resin composite repair material then subjected to micro-shear bond strength ‎testing using a universal testing machine. Results: There was a significant difference ‎between different groups (f=4.47, p=0.002). The highest bond strength was found in group ‎‎(II) (28.74±4.18) (MPa), followed by group (IV) (25.00±5.09) (MPa), then group (VI) ‎‎(23.36±5.08) (MPa), group (III) (22.07±5.30) (MPa) and group (I) (21.57±7.64) (MPa), ‎while the lowest bond strength was found in group (V) (18.09±4.04) (MPa). Post hoc ‎pairwise comparisons showed group (II) to have significantly higher values than groups (I) ‎and (V). Conclusion: The best surface treatment for repair of an aged ORMOCER based ‎resin composite could be the use of fine diamond bur with universal adhesive, followed by ‎air abrasion with or without silane. Silanation is an essential step with acid etching while ‎repairing ORMOCER based resin composite.‎

Biomechanical properties of bonded dentin are important factors for resin restoration. We evaluated the hardness and elastic modulus of bonded sound and caries-affected primary tooth dentin using a one-step adhesive system, and observed the microstructure of the bonded interface. Six sound and six carious primary teeth were used. For sound teeth, flat occlusal dentin surfaces were prepared with a water-cooled high-speed diamond bur. For carious teeth, infected dentin was stained with a caries detector and removed with a water-cooled low-speed round steel bur and hand instruments. The prepared dentin was bonded with One-Up Bond F Plus (Tokuyama Dental Co., Tokyo, Japan). The resin-dentin interface and dentin beneath the interface were measured with a nano-indentation tester and observed with SEM and TEM. For both the carious and sound teeth, there was no significant difference between the hardness of the interfacial dentin and dentin 10-80 microm beneath the interface. However, the Young's modulus of the interfacial dentin was significantly lower than the dentin 40-80 microm (carious teeth) or 50-80 microm (sound teeth) beneath the interface. Both the hardness and Young's modulus of the interfacial dentin were not significantly different between the carious and sound teeth. Compared to the sound dentin, the hybrid layer on the caries-affected dentin was thicker and exhibited more complicated morphologic features. The thickness of the hybrid layers was generally less than 1 microm.

PurposeThis umbrella review systematically appraised published systematic reviews on Minimal Intervention Dentistry interventions carried out to manage dentine carious primary teeth to determine how best to translate the available evidence into practice, and to provide recommendations for what requires further research.MethodAn experienced information specialist searched MEDLINE, Embase, Cochrane Database of Systematic Reviews, Epistemonikos, Joanna Briggs Institute Database of Systematic Reviews and Implementation Reports, and the NIHR Journals Library. In addition, the PROSPERO database was searched to identify forthcoming systematic reviews. Searches were built around the following four concepts: primary teeth AND caries/carious lesion AND Minimal Intervention Dentistry AND systematic review/meta-analysis. Searches were restricted to English language, systematic reviews with/without meta-analyses published between January 2000 and August 2020. Two reviewers independently screened all titles and abstracts. Interventions included involved no dentine carious tissue removal (fissure sealants, resin infiltration, topical application of 38% Silver Diamine Fluoride, and Hall Technique), non-restorative caries control, and selective removal of carious tissue involving both stepwise excavation and atraumatic restorative treatment. Systematic reviews were selected, data extracted, and risk of bias assessed using ROBIS by two independent reviewers. Studies overlap was calculated using corrected covered area.ResultsEighteen systematic reviews were included in total; 8 assessed the caries arresting effects of 38% Silver Demine Fluoride (SDF), 1 on the Hall Technique (HT), 1 on selective removal of carious tissue, and eight investigated interventions using atraumatic restorative treatment (ART). Included systematic reviews were published between 2006 and 2020, covering a defined time frame of included randomised controlled trials ranging from 1969 to 2018. Systematic reviews assessed the sealing efficacy of fissure sealants and resin infiltration in carious primary teeth were excluded due to pooled data reporting on caries arrest in both enamel and outer third of dentine with the majority of these carious lesions being limited to enamel. Therefore, fissure sealants and resin infiltration are not recommended for the management of dentinal caries lesions in primary teeth. Topical application of 38% SDF showed a significant caries arrest effect in primary teeth (p < 0.05), and its success rate in arresting dental caries increased when it was applied twice (range between 53 and 91%) rather than once a year (range between 31 and 79%). Data on HT were limited and revealed that preformed metal crowns placed using the HT were likely to reduce discomfort at time of treatment, the risk of major failure (pulp treatment or extraction needed) and pain compared to conventional restorations. Selective removal of carious tissue particularly in deep carious lesions has significantly reduced the risk of pulp exposure (77% and 69% risk reduction with one-step selective caries removal and stepwise excavation, respectively). ART showed higher success rate when placed in single surface compared to multi-surface cavities (86% and 48.7–88%, respectively, over 3 years follow-up).ConclusionMinimal Intervention Dentistry techniques, namely 38% SDF, HT, selective removal of carious tissue, and ART for single surface cavity, appear to be effective in arresting the progress of dentinal caries in primary teeth when compared to no treatment, or conventional restorations. There is clear need to increase the emphasis on considering these techniques for managing carious primary teeth as a mainstream option rather than a compromise option in circumstances where the conventional approach is not possible due to cooperation or cost.

Aim The objective of this in vitro study was to evaluate the bond strength of universal adhesive systems in self-etch and etch-and-rinse modes at the repair interface between aged and new composite resins. Materials and Methods Composite resin (Filtek Z250) was thermocycled to represent aged composite resin to be repaired. New composite resin was placed over the aged substrate after surface conditioning: NC (negative control, no surface treatment), A (adhesive only), SBM (Scotchbond Multi-Purpose in etch-and-rinse mode), CSE (Clearfil SE Bond in self-etch mode), SBU (Single Bond Universal), ABU (All Bond Universal), and TBU (Tetric N-Bond Universal). Universal adhesives (SBU, ABU, and TBU) were applied both in etch-and-rinse and self-etch modes. 1 mm × 1 mm × 8 mm beams were sectioned, and microtensile bond strength was measured after 24 hours of water storage and 10,000 thermocycling processes (n = 20/group). The fracture surfaces were observed with a scanning electron microscope to evaluate the failure pattern. Results The repair bond strength between the old and new composite resins was material-dependent. Universal adhesives significantly improved the repair bond strength (p < 0.05), while no significant difference was observed between the etch modes (self-etch or etch-and-rinse) for each universal adhesive (p > 0.05). Thermocycling significantly reduced the bond strength in all groups (p < 0.05). Conclusion Universal adhesives in both etch-and-rinse and self-etch modes outperformed the conventional 3-step etch-and-rinse and 2-step self-etch adhesive systems in terms of resin repair bond strength.

To observe the effects of glass-ionomer cement (GIC) lining on the risk of pulpal complications in deep occlusal cavities with resin-based restorations. Fifty-three patients, aged 18-30years, who had one or two deep occlusal carious lesions (≥3mm in depth) in molars, were recruited. Dental caries were removed, and the prepared cavity was restored with resin composite using one of two restorative procedures: (a) without GIC lining; and (b) with (resin-modified) GIC lining. Restored teeth were evaluated for any pulpal complications (subjective symptoms, objective signs or loss of tooth vitality) at 1month (baseline), 1year, and 2years after restoration. After excluding shallow cavities, 31 restorations without GIC lining, and 31 restorations with GIC lining, were placed and recalled at baseline without any pulpal complications. At the 1- and 2-year recalls, six patients who had restorations in group 1, and 13 in group 2, had dropped out. None of the remaining teeth in the two groups exhibited pulpal complications at either recall period, regardless of GIC lining placement. The absence of GIC lining does not increase the risk of pulpal complications in deep occlusal cavities restored with resin-based restorations in either the short or long term.

This research study’s purpose was to evaluate the mechanical and chemical surface treatment methods for self-cured acrylic resin repaired with a resin composite employing a universal adhesive agent. Eighty self-cured acrylic resins were built and designed into eight groups of ten specimens and surface conditioned using sandblasting (SB) and/or with methylmethacrylate monomer (MMA) and/or universal adhesive (UA) as follows: Group 1, non-surface modified; Group 2, SB; Group 3, UA; Group 4, SB + UA; Group 5, MMA; Group 6, SB + MMA; Group 7, MMA + UA; Group 8, SB + MMA + UA. A template was put on the specimen center, and the pushed resin composites. Mechanical testing machinery was used to examine the samples’ shear bond strength (SBS) values. To examine failure patterns, the debonded specimen surfaces were examined using a scanning electron microscope. The one-way ANOVA method was used to evaluate these data, and Tukey’s test was used to determine the significance level (p &lt; 0.05). The highest SBS was obtained in Group 8 (27.47 ± 2.15 MPa); however, it was statistically equivalent to Group 7 (25.85 ± 0.34 MPa). Group 1 (4.45 ± 0.46 MPa) had the lowest SBS, but it was not statistically significant compared to Group 2 (5.26 ± 0.92 MPa). High SBS values were frequently correlated with cohesive patterns. The application of MMA prior to UA is the best method for increasing the SBS between self-cured acrylic resin and resin composite interfaces. However, the use of SB is not significantly different from not using SB.