Does immediate dentin sealing influence postoperative sensitivity in teeth restored with indirect restorations? A systematic review and meta-analysis

Is immediate dentin sealing a mandatory or optional clinical step for indirect restorations?

OBJECTIVE

The use of immediate dentin sealing (IDS) following tooth preparation for indirect restorations is well-supported by laboratory studies. The inclusion of IDS as a mandatory clinical step, it must be firmly supported by evidence from randomized clinical trials (RCT). The objective of this study is to assess whether IDS should be added as a mandatory procedure in all indirect restorations, taking into consideration clinically significant outcomes for the patient, such as restoration longevity and hypersensitivity.

MATERIALS AND METHODS

A bibliographic search was carried out in the PubMed. In addition, a manual search was conducted in the references of literature reviews.

RESULTS

Data from four RCT were included. Two studies assessed preparations for full crowns, and two assessed preparations for partial restorations. Data from full crown preparations were subjected to a meta-analysis, revealing a reduction in hypersensitivity incidence in the IDS group 1 week after restoration cementation. With respect to hypersensitivity, IDS seems to offer advantages exclusively during the provisional phase and up to 1 week following the cementation of the final restoration. One study has shown no difference on longevity.

CONCLUSION

The use of IDS should be considered as an elective clinical step during the rehabilitation with indirect restorations.

CLINICAL SIGNIFICANCE

IDS is an elective clinical step that should be considered in patients and preparations with a higher risk of sensitivity between appointments.

Clinical benefits of immediate dentin sealing: A systematic review and meta-analysis

STATEMENT OF PROBLEM

The clinical complications, success, and survival rates of indirect restorations delivered with the immediate dentin sealing protocol are unclear.

PURPOSE

The purpose of this systematic review and meta-analysis was to find and collect evidence on the clinical complication, success, and survival rates of indirect restorations delivered with immediate dentin sealing.

MATERIAL AND METHODS

Electronic databases were searched for clinical studies on immediate dentin sealing up to December 2023, without language or time limitations. The records were included if they were clinical trials evaluating the clinical complication and survival rates of indirect restorations bonded to tooth substrate sealed immediately after preparation with suitable resin bonding. The extracted data were analyzed via Review Manager 5.4 for meta-analysis (α=.05).

RESULTS

A total of 11 studies were included in this review. The clinical complication rate was lower for immediately sealed dentin than for protocols without dentin sealing. The survival rate of restorations luted with the immediate dentin sealing protocol was higher (96.4% to 100%) than that of immediate dentin sealing (81.8% to 96.7%), negatively correlated with the observation time. The intensity and incidence of postoperative sensitivity were statistically significantly lower for restorations with immediate dentin sealing than for those without dentin sealing or conventionally cemented (P<.05).

CONCLUSIONS

Immediate dentin-sealed indirect restorations had fewer clinical complications and higher success and survival rates than those delivered without dentin sealing. To avoid postoperative sensitivity or reduce its intensity, dentin surfaces should be sealed immediately after preparation. More long-term randomized clinical trials are recommended to confirm these evidence-based conclusions.

A comprehensive review of resin luting agents: Bonding mechanisms and polymerisation reactions

The field of dentistry is constantly evolving and increasingly embracing minimally invasive approaches. One such approach, which is bonding to the tooth structure, particularly enamel, has been shown to offer the most predictable outcomes. However, there are instances where significant tooth loss may limit treatment options for a restorative dentist. In these scenarios, indirect restoration might be the preferred treatment option. This literature review provides a comprehensive examination of the currently available resin luting agents and their bonding requirements. It provides valuable insights for dental professionals seeking an in-depth understanding of the current state of the field and the future prospects of dental adhesion.

Clinical longevity of direct and indirect posterior resin composite restorations: An updated systematic review and meta-analysis

OBJECTIVES

To answer the PICO(S) question: Is there a difference in clinical longevity between direct and indirect resin composite restorations placed on permanent posterior teeth?

DATA

Randomized controlled clinical trials (RCTs) investigating direct and indirect resin composite restorations in posterior permanent teeth were considered.

SOURCES

Several electronic databases were searched, with no language or date restrictions. The revised Cochrane Collaboration's tool for assessing risk of bias (RoB-2) was used to analyze the studies; meta-analyses were run and the certainty of evidence was assessed by the GRADE tool. A subgroup meta-analysis was performed for resin composite restorations placed on posterior worn dentition.

STUDY SELECTION

Twenty-three articles were included in qualitative synthesis, while 8 studies were used for meta-analyses. According to the RoB-2 tool, 5 studies were ranked as "low risk", 7 had "some concerns", while 11 papers were rated as "high risk" of bias. There were no statistically significant differences in short-term (p = 0.27; RR=1.54, 95% CI [0.72, 3.33]), medium-term (p = 0.27; RR=1.87, 95% CI [0.61, 5.72]) and long-term longevity (p = 0.86; RR=0.95, 95% CI [0.57, 1.59]). The choice of restorative technique had no influence on short-term survival of resin composite restorations placed on worn dentition (p = 0.13; RR=0.46, 95% CI [0.17, 1.25]). The certainty of evidence was rated as "very low".

CONCLUSIONS

Direct and indirect resin composite restorations may show similar clinical longevity in posterior region, regardless of the observation period or substrate (wear-affected and non-affected dentition). The very low quality of evidence suggests that more long-term RCTs are needed to confirm our results.

Resin composite cements: Current status and a novel classification proposal

OBJECTIVES

Currently, a classification of resin cements that includes relatively recently formulated ("universal") cements is lacking. Furthermore, the terminology used to define different resin cements in the scientific reports is inconsistent. Accordingly, this work aims to: (i) propose a novel classification of resin composite cements; (ii) disambiguate the term "universal cements" and (iii) present an overview of the properties of these cements.

METHODS

An analysis of peer-reviewed literature (PubMed search), as well as market research on definitive resin composite cements were performed.

RESULTS

A tendency toward simplified and versatile luting materials was observed both in the scientific literature and on the dental market with the advent of self-adhesive/one-step resin cements. However, additional priming procedures were necessary to improve their bonding performance in certain clinical situations. Hence, several cements that can be applied both in adhesive and self-adhesive mode were introduced. These cements are associated with a universal adhesive resin, that can be used as a tooth and/or restorative material primer, without the need for other priming systems, regardless of the substrate. These systems should be considered truly universal. Therefore, we hereby suggested a new classification of resin-based cements: (1) adhesive/multi-step; (2) self-adhesive/one-step; (3) universal cements (one- or multi-step). Despite promising in vitro results, clinical trials and long-track laboratory studies are necessary to confirm the reliability of the universal cements.

CONCLUSIONS

This review presented the current advances in the field of resin-based cements, which are reflected in the proposed classification. The term "universal cement" was disambiguated, which will help standardize the terminology used in published research.

CLINICAL SIGNIFICANCE

The classification of resin-based cements and a better understanding of the proper terminology will help standardize the terminology in published research, as well as improve the understanding of the clinical practitioners of the different indications and possible modalities of use of the available cements.

Selective adhesive luting: A novel technique for improving adhesion achieved by universal resin cements

OBJECTIVE

We aimed to introduce the concept of "Selective adhesive luting-SAL" which is explained through clinical steps and supported by preliminary laboratory evidence.

CLINICAL CONSIDERATIONS

Cementation with rubber dam is difficult to perform in case of short abutment teeth and/or subgingival crown margins. By means of universal resin cements/universal adhesive systems, which can be employed in self-adhesive as well as adhesive luting procedures, this paper presents a novel technique allowing clinicians to perform reliable cementation where rubber dam isolation is difficult. The SAL technique entails the application of a universal adhesive system only on easily accessible abutment surfaces, enabling simultaneous adhesive and self-adhesive luting in different portions of the abutment. The SAL clinical workflow is explained through prosthodontic rehabilitation of maxillary right central incisor affected by microdontia and restored with a lithium-disilicate crown. Furthermore, our laboratory microshear bond strength study supports the rationale behind SAL application demonstrating higher bond strength even when the adhesive resin is placed only on one portion of the cementation substrate.

CLINICAL SIGNIFICANCE

This article advocates the application of SAL technique in clinical situations where effective adhesive luting is uncertain, since it can improve the adhesion between the tooth and universal resin cements.

Glutaraldehyde-based desensitizers' influence on bonding performances and dentin enzymatic activity of universal adhesives

OBJECTIVES

To evaluate the influence of two glutaraldehyde-based desensitizers (L: GLUMA Desensitizer, Heraeus Kulzer and G: GLUMA Desensitizer PowerGel) prior to the adhesive procedures on microtensile bond strength (µTBS) to dentin and endogenous enzymatic activity.

METHODS

Noncarious human third molars (N = 48) were cut to expose middle coronal dentin. Six experimental groups were formed according to the dentin pre-treatment (L or G) and the universal adhesives (IBU - iBond universal, Kulzer or AU - Adhese Universal, Ivoclar Vivadent) used in the self-etch mode (n = 8): 1) L/IBU; 2) G/IBU; 3) IBU; 4) L/AU; 5) G/AU; 6) AU. Specimens were cut into sticks and stressed until failure after 24 h (T0) or 1 yr of aging (T12). Additional 4 teeth were used for in situ zymography evaluation and data were statistically analyzed (α = 0.05).

RESULTS

Dentin pre-treatment, adhesive and aging statistically influenced bond strength and enzymatic activity (P<0.001). AU demonstrated higher bond strength values than IBU (P<0.001). The L resulted in higher bond strength compared to the G and control groups (P<0.001). aging statistically influenced bonding performance, especially when no dentin pre-treatment was performed (P<0.001). In situ zymography revealed that at baseline the control groups exhibited lower interfacial fluorescence compared to the experimental groups, irrespective of the adhesive used (P<0,001). However, after 1 yr of artificial storage, no differences were found among the groups (P>0.05).

CONCLUSIONS

Glutharldeadeyde-based products increased bond strength and determined a stabilization of the adhesive interface over time apparently not related to the MMPs inhibition.

CLINICAL SIGNIFICANCE

The results of this in vitro study suggest that the application of glutaraldehyde-based desensitizers prior to the adhesive procedures when associated with universal adhesives could result in increased bond strength and stabilization of the adhesive interface over time.

Effect of temporary cements and their removal methods on the bond strength of indirect restoration: a systematic review and meta-analysis

OBJECTIVES

For a conventional indirect restoration, temporary cementation inevitably contaminated collapsed dentin collagen. The purpose of this review was to evaluate the optimal strategy for minimizing its negative effects.

MATERIAL AND METHODS

Databases such as PubMed, Web of Science, EMBASE, and the Cochrane Library were searched for in vitro studies, involving the influence of immediate dentin sealing (IDS), different temporary cements, and their removal strategies on dentin bond strength. The meta-analysis used the inverse variance method with effect method of the standardized mean difference and statistical significance at p ≤ 0.05. The I² value and the Q-test were used to assess the heterogeneity.

RESULTS

A total of 14 in vitro trials were subjected to the meta-analysis. Within the study's limitations, we assumed that IDS eliminated the negative effects of temporary bonding, achieving the comparable immediate bond strength with the control (p = 0.46). In contrast, under delayed dentin sealing (DDS), temporary cementation statistically decreased bond strength (p = 0.002). Compared with resin-based and non-eugenol zinc oxide cements, polycarboxylate and calcium hydroxide cements performed better on bond strength with no statistical difference from the control group (p > 0.05). Among the removal methods of temporary cements, the Al₂O₃ abrasion restored the decreased bond strength (p = 0.07) and performed better than hand instruments alone (p = 0.04), while pumice removal slightly reduced the bond strength in contrast with the control group (p = 0.05, 95% CI =  - 1.62 to 0).

CONCLUSIONS

The choices of IDS, polycarboxylate and calcium hydroxide temporary cements, Al₂O₃ abrasion removal method were feasible and efficient to enhance the bond strength.

CLINICAL RELEVANCE

It is worthwhile applying IDS technique, polycarboxylate and calcium hydroxide temporary cements during indirect restoration. The Al₂O₃ abrasion of cleaning dentin can minimize the negative effects of temporary cement.

The effect of different application modes of a 1-step self-etch adhesive on the clinical performance of Class I composite restorations: A randomized controlled clinical trial

OBJECTIVE

To evaluate the clinical performance of a 1-step self-etch dentin adhesive that was applied according to the manufacturers' recommendations, doubling the adhesive application time and layer in Class I cavities with a composite resin.

MATERIALS AND METHODS

A total of 39 patients aged between 14 and 43 (mean age: 19.1) years were enrolled in the study. Each patient received three restorations. In these three restorations, a 1-step self-etch adhesive was applied according to the manufacturer's recommendations (control group), by doubling the adhesive application time, and with double layers. The restorations were evaluated according to modified USPHS criteria at baseline, and 1, 2, 3, and 4-year recalls.

RESULTS

After 4 years, the success rate was 100% for restorations with the adhesive applied according to the manufacturers' recommendations, 96.9% for restorations applied by doubling the adhesive application time, and 93.8% for restorations applied with double adhesive layers. There was no significant difference between the three application methods among all the evaluation periods regarding the evaluation criteria.

CONCLUSIONS

The 4-year success rates of a 1-step self-etch dentin adhesive that was applied according to the manufacturers' recommendation, by doubling the adhesive application time, and with double layers were excellent.

CLINICAL SIGNIFICANCE

It is not recommended to double the adhesive application time nor apply a double layer of a 1-step self-etch adhesive because it does not improve the clinical performance of Class I composite restorations.

Immediate Dentin Sealing for Adhesive Cementation of Indirect Restorations: A Systematic Review and Meta-Analysis

Immediate dentin sealing (IDS) involves applying an adhesive system to dentin directly after tooth preparation, before impression. This was considered an alternate to delayed dentin sealing (DDS), a technique in which hybridization is performed following the provisional phase and just before the indirect restoration luting procedure. This study aimed to compare the bond strength of restorations to dentin of the IDS and the DDS techniques throughout a systematic review and meta-analysis. The following PICOS framework was used: population, indirect restorations; intervention, IDS; control, DDS; outcomes, bond strength; and study design, in vitro studies. PubMed (MedLine), The Cochrane Library, ISI Web of Science, Scielo, Scopus, and Embase were screened up to January 2022 by two reviewers (L.H. and R.B.). In vitro papers studying the bond strength to human dentin of the IDS technique compared to the DDS technique were considered. Meta-analyses were carried out by using a software program (Review Manager v5.4.1; The Cochrane Collaboration). Comparisons were made by considering the adhesive used for bonding (two-step etch-and-rinse, three step etch-and-rinse, one-step self-etch, two-step self-etch, and universal adhesives). A total of 3717 papers were retrieved in all databases. After full-text assessment, 22 potentially eligible studies were examined for qualitative analysis, leaving a total of 21 articles for the meta-analysis. For the immediate bond strength, regardless of the adhesive strategy used, the IDS technique improved the bond strength of restorations to the dentin (p < 0.001). Taking into account the subgroup analysis, it seems that the use of the IDS technique with a two-step etch-and-rinse or a one-step self-etch adhesive system does not represent any advantage over the DDS technique (p = 0.07, p = 0.15). On the other hand, for the aged bond strength, regardless of the adhesive strategy used, the IDS technique improved the bond strength of restorations to the dentin (p = 0.001). The subgroups analysis shows that this improvement is observed only when a three-step etch-and-rinse adhesive system (p < 0.001) or when a combination of an adhesive system plus a layer of flowable resin (p = 0.01) is used. The in vitro evidence suggests that the use of the IDS technique improves the bond strength of dentin to resin-based restorations regardless of the adhesive strategy used. The use of a three-step etch-and-rinse adhesive system or the combination of an adhesive system plus a layer of flowable resin seems to considerably enhance the bond strength in the long term.