Randomized controlled clinical trial on the efficacy of a novel antimicrobial chewing gum in reducing plaque and gingivitis in adolescent orthodontic patients.

OBJECTIVES: Chewing gums containing antiseptics or other antimicrobial substances may be effective in reducing plaque and gingivitis. Therefore, the aim of this randomized placebo-controlled clinical trial was to investigate the efficacy of a novel antimicrobial chewing gum containing essential oils (cinnamon, lemon, peppermint) and extracts on reduction of dental plaque and gingivitis as well as on oral health-related quality of life (OHRQoL) in adolescent orthodontic patients. MATERIALS: 52 patients (11-22 years of age) were randomly assigned to use a test chewing gum (COVIDGUM, Clevergum) or a commercially available control chewing gum over a period of 10 days. Approximal plaque index (API), papillary bleeding index (PBI) and an OHRQoL questionnaire for children (COHIP-G19) were assessed at baseline (BL), after 10 days (10d) and 30 days (30d). In addition, oral health and oral hygiene related questions of the COHIP-G19 questionnaire were evaluated separately in subscales at each timepoint. Data were analyzed using non-parametrical statistical procedures (α = 0.05). RESULTS: API and PBI decreased significantly over time from BL to 10d and from BL to 30d in both groups, without significant differences between the groups. In both groups, the COHIP-G19 score, oral health subscale and oral hygiene subscale decreased significantly over time. Regarding the oral hygiene subscale, the test group showed significantly better scores at 30d (p = 0.011). CONCLUSION: Both chewing gums performed similarly effective in terms of reducing plaque accumulation and gingival inflammation and improving OHRQoL. CLINICAL RELEVANCE: Chewing gums without antimicrobial ingredients may be sufficient to decrease plaque accumulation and gingival inflammation.

Optimal effective concentration combinations (OPECCs) for binary application of membrane-targeting antiseptics and TMPyP-mediated antimicrobial photodynamic therapy.

The widespread occurrence of multi-resistant bacteria is a health problem of global dimension. Infections caused by multi-resistant pathogens are difficult to treat and often associated with high mortality. Therefore, new treatment strategies are of interest, such as the use of differently acting antibacterial concepts. One of these new concepts is the use of antiseptics in combination with the antibacterial photodynamic therapy (aPDT). Currently, no method has yet been established as a standard procedure for investigating combined effects and evaluating them in a generally valid and unambiguous manner. The focus of this study was on how cationic antiseptics benzalkonium chloride (BAC) and chlorhexidine digluconate (CHX) behave in a combined application with aPDT using the photosensitizer TMPyP. For this purpose, BAC and CHX were applied in combination with the aPDT using TMPyP in non-lethal concentrations to the three bacteria Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis. The results of the combination experiments with sublethal concentrations of BAC or CHX with the aPDT showed that the binary application had a lethal effect. Irrespective of the bacteria, the reduction in concentrations in OPECC, compared to individual concentrations, was more than 50% for TMPyP, 23-40% for BAC, and 18-43% for CHX. Furthermore, the optimal effective concentration combinations (OPECCs) could be determined. The latter showed that the combined application allowed the reduction of both concentrations compared to the single application.

BMSC-HNC Interaction: Exploring Effects on Bone Integrity and Head and Neck Cancer Progression.

In recent research, the tumor microenvironment has been shown to attract mesenchymal stromal cells (MSCs), which is of particular interest due to its implications for cancer progression. The study focused on understanding the interaction between bone marrow-derived MSCs (BMSCs) and head and neck cancer (HNC) cells. This interaction was found to activate specific markers, notably the osteogenic marker alkaline phosphatase and the oncogene Runx2. These activations corresponded with the release of collagenase enzymes, MMP9 and MMP2. To gain insights into bone resorption related to this interaction, bovine bone slices were used, supporting the growth of "heterogeneous spheroids" that contained both BMSCs and HNC cells. Through scanning electron microscopy and energy-dispersive X-ray (EDX) analysis, it was observed that these mixed spheroids were linked to a notable increase in bone degradation and collagen fiber exposure, more so than spheroids of just BMSCs or HNC cells. Furthermore, the EDX results highlighted increased nitrogen content on bone surfaces with these mixed clusters. Overall, the findings underscore the significant role of BMSCs in tumor growth, emphasizing the need for further exploration in potential cancer treatment strategies.

Randomized Clinical Split-Mouth Study on Partial Ceramic Crowns Luted with a Self-adhesive Resin Cement with or without Selective Enamel Etching: Long-Term Results after 15 Years.

PURPOSE: This follow-up of a randomized clinical split-mouth study aimed to investigate the influence of selective enamel etching on the long-term clinical performance of partial ceramic crowns (PCCs) luted with a self-adhesive resin cement. MATERIALS AND METHODS: 43 patients received two PCCs (Vita Mark II; Cerec 3D) each for the restoration of extensive lesions with multiple cusp coverage, inserted with a self-adhesive resin cement (RelyX Unicem, RXU). Using a split-mouth design, one PCC received additional selective enamel etching (RXU+E) and one did not (RXU-E). Patients were clinically evaluated at baseline and after up to 15 years (median observation period 176 months) using modified USPHS and FDI criteria. The data were analyzed non-parametrically (chi-squared tests, α = 0.05). Clinical survival of all restorations after 15 years was evaluated using the Kaplan-Meier analysis. RESULTS: After 15 years, 19 patients were available for clinical assessment (recall rate: 56%). Kaplan-Meier analysis showed a cumulative survival of 78.1% for RXU+E and of 42.9% for RXU-E, indicating a significantly higher survival rate for RXU+E (p = 0.004). Regarding the clinical performance of PCCs available for the 15-year evaluation, no statistically significant differences were found between RXU+E and RXU-E using modified USPHS and FDI criteria. Both groups revealed significant deterioration over time regarding surface luster, marginal adaptation, and marginal discoloration. RXU+E resulted in significantly inferior anatomic form over time and a significant improvement in post-operative hypersensitivity compared to baseline. CONCLUSION: For posterior PCCs, selective enamel etching can be recommended based on higher survival rates after 15 years. Clinically, deterioration due to aging is similar in both groups.

General diseases and medications in 687 patients reporting on adverse effects from dental materials.

OBJECTIVES: Examination of patients claiming adverse effects from dental materials can be very challenging. Particularly, systemic aspects must be considered besides dental and orofacial diseases and allergies. Therefore, the aim of this study was to investigate a cohort of 687 patients reporting on adverse effects from dental materials focusing on findings related to known general diseases or conditions or medication-related findings with relevance to their subjective complaints. METHODS: Six hundred eighty-seven patients visiting a specialized consultation on claimed adverse effects from dental materials were retrospectively investigated for their subjective complaints, findings related to known general diseases or conditions, medication-related findings, dental and orofacial findings, or allergies with relevance to their subjective complaints. RESULTS: The most frequent subjective complaints were burning mouth (44.1%), taste disorders (28.5%), and dry mouth (23.7%). In 58.4% of the patients, dental and orofacial findings relevant to their complaints could be found. Findings related to known general diseases or conditions or medication-related findings were found in 28.7% or 21.0% of the patients, respectively. Regarding medications, findings related to antihypertensives (10.0%) and psychotropic drugs (5.7%) were found most frequently. Relevant diagnosed allergies toward dental materials were found in 11.9%, hyposalivation in 9.6% of the patients. In 15.1% of the patients, no objectifiable causes for the expressed complaints could be found. CONCLUSIONS: For patients complaining of adverse effects from dental materials, findings related to known general diseases or conditions and medications should be given particular consideration, while still in some patients, no objectifiable causes for their complaints can be found. CLINICAL RELEVANCE: For patients complaining about adverse effects from dental materials, specialized consultations and close collaboration with experts from other medical fields are eligible.

Preprocedural mouthwashes for infection control in dentistry-an update.

OBJECTIVES: Aerosols and splatter are routinely generated in dental practice and can be contaminated by potentially harmful bacteria or viruses such as SARS-CoV-2. Therefore, preprocedural mouthwashes containing antiseptic agents have been proposed as a potential measure for infection control in dental practice. This review article aims to summarize the clinical (and, if insufficient, preclinical) evidence on preprocedural mouthwashes containing antiseptic agents and to draw conclusions for dental practitioners. METHODS: Literature on preprocedural mouthwashes for reduction of bacterial or viral load in dental aerosols was searched and summarized. RESULTS: Preprocedural mouthwashes, particularly those containing chlorhexidine digluconate (CHX), cetylpyridinium chloride (CPC), or essential oils (EO), can significantly reduce the bacterial load in dental aerosols. With respect to viruses such as HSV-1, there are too little clinical data to draw any clear recommendations. On the other hand, clinical data is consolidating that CPC-containing mouthwashes can temporarily reduce the intraoral viral load and infectivity in SARS-CoV-2 positive individuals. Nevertheless, potential risks and side effects due to regular antiseptic use such as ecological effects or adaptation of bacteria need to be considered. CONCLUSIONS: The use of preprocedural mouthwashes containing antiseptics can be recommended according to currently available data, but further studies are needed, particularly on the effects on other viruses besides SARS-CoV-2. When selecting a specific antiseptic, the biggest data basis currently exists for CHX, CPC, EO, or combinations thereof. CLINICAL RELEVANCE: Preprocedural mouthwashes containing antiseptics can serve as part of a bundle of measures for protection of dental personnel despite some remaining ambiguities and in view of potential risks and side effects.

Galleria mellonella as an alternative in vivo model to study implant-associated fungal infections.

Fungal implant-associated bone infections are rare but difficult to treat and often associated with a poor outcome for patients. Candida species account for approximately 90% of all fungal infections. In vivo biofilm models play a major role to study biofilm development and potential new treatment options; however, there are only a very few in vivo models to study fungi-associated biofilms. Furthermore, mammalian infection models are replaced more and more due to ethical restrictions with other alternative models in basic research. Recently, we developed an insect infection model with Galleria mellonella larvae to study biofilm-associated infections with bacteria. Here, we further expanded the G. mellonella model to study in vivo fungal infections using Candida albicans and Candida krusei. We established a planktonic and biofilm-implant model to test different antifungal medication with amphotericin B, fluconazole, and voriconazole against the two species and assessed the fungal biofilm-load on the implant surface. Planktonic infection with C. albicans and C. krusei showed the killing of the G. mellonella larvae at 5 × 105 colony forming units (CFU). Treatment of larvae with antifungal compounds with amphotericin B and fluconazole showed significant survival improvement against planktonic C. albicans infection, but voriconazole had no effect. Titanium and stainless steel K-wires were preincubated with C. albicans and implanted inside the larvae to induce biofilm infection on the implant surface. The survival analysis revealed significantly reduced survival of the larvae with Candida spp. infection compared to noninfected implants. The treatment with antifungal amphotericin B and fluconazole resulted in a slight and nonsignificant improvement survival of the larvae. The treatment with the antifungal compounds in the biofilm-infection model was not as effective as in the planktonic infection model, which highlights the resistance of fungal biofilms to antifungal compounds like in bacterial biofilms. Scanning electron microscopy (SEM) analysis revealed the formation of a fungal biofilm with hyphae and spores associated with larvae tissue on the implant surface. Thus, our study highlights the use of G. mellonella larvae as alternative in vivo model to study biofilm-associated implant fungal infections and that fungal biofilms exhibit high resistance profiles comparable to bacterial biofilms. The model can be used in the future to test antifungal treatment options for fungal biofilm infections.

Randomized clinical split-mouth study on a novel self-adhesive bulk-fill restorative vs. a conventional bulk-fill composite for restoration of class II cavities - results after three years.

OBJECTIVES: This randomized prospective split-mouth study evaluated the clinical performance of a novel, tooth-colored, self-adhesive bulk-fill restorative (SABF, 3M) for restoration of class II cavities as compared to a conventional bulk-fill composite (Filtek One, 3M; FOBF) over 36 months. The null-hypothesis was that both materials perform equally regarding clinical success and performance according to the FDI clinical criteria and scoring system. METHODS: 30 patients received one SABF and one FOBF restoration each. For FOBF, Scotchbond Universal (3M) was used as adhesive (self-etch mode), whereas SABF was applied without adhesive. Two blinded examiners evaluated the restorations at baseline, 24 and 36 months using FDI criteria. Data were analyzed non-parametrically (χ2-tests; α=0.05). RESULTS: 29 patients were available for the 24- and 36-month examinations. Clinical success rate was 96.6% for both materials at 36-mo (one restoration failure due to secondary caries each). All other restorations revealed clinically acceptable FDI scores at all recalls. FOBF performed significantly better than SABF at all time points regarding surface lustre (p<0.001) and color match and translucency (p<0.001) and regarding marginal staining at 36-months (p=0.008). Marginal staining and marginal adaptation deteriorated significantly over time for both materials (both p<0.001). CONCLUSIONS: The null-hypothesis could only partially be rejected. Both materials performed similarly regarding clinical success and performance within 36 months of clinical service, but SABF exhibited significantly inferior, but clinically fully acceptable esthetic properties as compared to FOBF. Both restorative materials showed clinically fully acceptable results over 36 months of clinical service and thus may be recommended for clinical use. CLINICAL SIGNIFICANCE: The novel tooth-colored self-adhesive bulk-fill restorative exhibited clinically fully acceptable results over 36 months of clinical service, similarly to a conventional bulk-fill restorative used with a universal adhesive, but with slight shortcomings in esthetic properties. Therefore, both restorative materials may be recommended for clinical use.

Ecological Effects of Daily Antiseptic Treatment on Microbial Composition of Saliva-Grown Microcosm Biofilms and Selection of Resistant Phenotypes.

Antiseptics are widely used in dental practice and included in numerous over-the-counter oral care products. However, the effects of routine antiseptic use on microbial composition of oral biofilms and on the emergence of resistant phenotypes remain unclear. Microcosm biofilms were inoculated from saliva samples of four donors and cultured in the Amsterdam Active Attachment biofilm model for 3 days. Then, they were treated two times daily with chlorhexidine digluconate (CHX) or cetylpyridinium chloride (CPC) for a period of 7 days. Ecological changes upon these multiple antiseptic treatments were evaluated by semiconductor-based sequencing of bacterial 16S rRNA genes and identification of amplicon sequence variants (ASVs). Furthermore, culture-based approaches were used for colony-forming units (CFU) assay, identification of antiseptic-resistant phenotypes using an agar dilution method, and evaluation of their antibiotic susceptibilities. Both CHX and CPC showed only slight effects on CFU and could not inhibit biofilm growth despite the two times daily treatment for 7 days. Both antiseptics showed significant ecological effects on the microbial compositions of the surviving microbiota, whereby CHX led to enrichment of rather caries-associated saccharolytic taxa and CPC led to enrichment of rather gingivitis-associated proteolytic taxa. Antiseptic-resistant phenotypes were isolated on antiseptic-containing agar plates, which also exhibited phenotypic resistance to various antibiotics. Our results highlight the need for further research into potential detrimental effects of antiseptics on the microbial composition of oral biofilms and on the spread of antimicrobial resistance in the context of their frequent use in oral healthcare.

Impact of access cavity cleaning on the seal of postendodontic composite restorations in vitro.

AIM: The aim of the study was to investigate the influence of cavity cleaning and conditioning on marginal integrity of directly placed post-endodontic composite class-I-restorations in vitro. METHODOLOGY: A total of 168 fully intact teeth without caries or fillings received pre-endodontic composite restorations (class-II) after their extraction. Occlusal endodontic access-cavities were prepared, and root canals were instrumented and filled with gutta-percha and an epoxy resin-based sealer. Prior to post-endodontic class-I-restoration, access cavities were completely contaminated with sealer, cleaned with alcohol and pre-treated as follows: cleaner only (alcohol), glycine-polishing, Al2 O3 sandblasting, carbide bur (immediate as well as delayed restoration). A positive control (not contaminated with sealer and adhesive used) and negative control (cleaner used but no adhesive) were established. Half of the teeth from each group were subjected to thermocycling and mechanical loading (TCML). Marginal integrity of post-endodontic restoration was evaluated in oro-vestibular or mesio-distal sections after AgNO3 dye penetration (DP) by standardized photomacroscopic imaging and expressed in per cent of margin length along all segments and separately for enamel, dentine and composite, respectively. Results were analysed non-parametrically (α = .05). RESULTS: No restorations or teeth fractured or debonded completely. Without TCML, the median DP of all segments was significantly higher for the negative control compared with all other groups in oro-vestibular cutting direction (53%; p = .002) and in mesio-distal cutting direction (51%; p ≤ .041). The other groups without TCML revealed 16%-24% DP (oro-vestibular) and 12%-24% DP (mesio-distal). With TCML, the median DP in oro-vestibular cutting direction for all segments ranged between 48% and 62% for all groups, a significant difference was only observed between glycine-polishing and carbide bur (p = .041). In mesio-distal cutting direction, the median DP in negative control was 69% with TCML and significantly higher compared with all other groups (p = .002). For all other groups, the median DP of all segments ranged between 28% and 40% with TCML without significant differences. Error rates method (k = 7) revealed a significant influence of TCML in general on penetration of all segments in both oro-vestibular and mesio-distal cutting directions. CONCLUSION: Additional access cavity pre-treatment after alcohol cleaning did not improve the marginal integrity of post-endodontic composite restorations. Thorough cleaning of the access cavity with alcohol seems to assure an acceptable marginal integrity to the tooth and restorative composite.

Biology of selective caries removal: a systematic scoping review protocol.

INTRODUCTION: Primary goal of restorative caries therapy is to preserve pulp vitality and the dentition. Whereas the conventional approach of complete caries removal aims at the elimination of all affected substances without regard to losses of hard tissue or pulp vitality, the innovative concept of selective caries removal (SCR) is characterised by a targeted and non-invasive excavation. It presents a lower risk of accidental pulp exposure, which reportedly has a positive effect on tooth survival. Although clinical data show the benefits of SCR, knowledge about the biological processes during this procedure in the pulp-dentine complex of permanent teeth is scarce. Hence, the aim of this work is to systematically scope the existing literature and map the existing evidence according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews guideline. This protocol details the scoping review's methodological and analytical approaches. METHODS AND ANALYSIS: First, a structure was established (phase I) as basis for a systematic scoping of literature (phase II). In the course of phase I, a total of 100 systematic reviews related to selective caries removal were searched in MEDLINE and information or theories on the biological processes were extracted. During the entire procedure, two reviewers independently screened the articles, and controversies were mediated by vote of a third reviewer. Eventually, it became apparent that different biological explanations can be organised into four categories: pulp response, cavity seal, remaining bacteria and cavity liner. Based on this structure, a search for original publications (phase II) will be performed and retrieved evidence will be assembled using a predefined conceptual framework. ETHICS AND DISSEMINATION: As primary data will not be included in this study, ethical approval is not required. Findings will be disseminated through peer-reviewed publications, conference presentations and summaries for key stakeholders.

One-year results of a novel self-adhesive bulk-fill restorative and a conventional bulk-fill composite in class II cavities-a randomized clinical split-mouth study.

OBJECTIVES: In the context of the phase-down of amalgam, development of easily applicable, permanent restorative materials is of high clinical interest. Aim of this study was to evaluate the clinical performance of a novel, tooth-colored, self-adhesive bulk-fill restorative (SABF, 3M Oral Care) and a conventional bulk-fill composite (Filtek One, 3M Oral Care; FOBF) for restoring class II cavities. The null-hypothesis tested was that both materials perform similar regarding clinical performance. MATERIALS AND METHODS: In this randomized split-mouth study, 30 patients received one SABF and one FOBF restoration each. Scotchbond Universal (3M Oral Care) was used as adhesive for FOBF (self-etch mode), while SABF was applied directly without adhesive. Restorations were evaluated by two blinded examiners at baseline, 6 months and 12 months employing FDI criteria. Non-parametric statistical analyses and χ2-tests (α = 0.05) were applied. RESULTS: Thirty patients (60 restorations) were available for the 6- and 12-month recalls exhibiting 100% restoration survival. All restorations revealed clinically acceptable FDI scores at all time points and for all criteria. Only regarding esthetic properties, FOBF performed significantly better than SABF regarding surface lustre (A1) and color match and translucency (A3) at all time points and marginal staining (A2b) at 12 months. CONCLUSIONS: The null-hypothesis could not be rejected. Both materials performed similarly regarding clinical performance within the first year of clinical service. SABF exhibited slightly inferior, but clinically fully acceptable esthetic properties as compared to FOBF. CLINICAL RELEVANCE: Within the limitations of this study, the self-adhesive bulk-fill restorative showed promising results and may be recommended for clinical use.

Randomized clinical split-mouth study on the performance of CAD/CAM-partial ceramic crowns luted with a self-adhesive resin cement or a universal adhesive and a conventional resin cement after 39 months.

Objectives To determine the clinical performance of partial ceramic crowns (PCCs) luted with a conventional resin cement combined with a universal adhesive without or with selective enamel etching or luted with a self-adhesive resin cement. Methods In a split-mouth design, each three CAD/CAM-PCCs (Vita Mark II, Cerec) were placed in 50 patients. Two PCCs were luted with a conventional resin cement (RelyX Ultimate) combined with a universal adhesive (Scotchbond Universal) without (SB-E) or with (SB+E) selective enamel etching. The third PCC was luted with a self-adhesive resin cement (RelyX Unicem 2; RXU). Chi-square tests (α≤0.05) were applied. Based on clinical failures (complete debonding or need for replacement of the restorations), Kaplan-Meier survival analysis was performed. Results 31 patients were evaluated clinically using FDI criteria at 39 months. Clinically acceptable results were detected over time, except for "fracture of material and retention" (inacceptable fractures and debondings). Within materials, statistically significant differences (p ≤ 0.003) between baseline and 39 months were found for "marginal adaptation" and "marginal staining". At 39-month, SB+E and SB-E showed significantly better results compared to RXU in "marginal adaptation"(p ≤ 0.021) and "marginal staining"(p ≤ 0.013). Kaplan-Meier analysis showed higher survival rates after 39 months for SB+E (96%) and SB-E (88%) compared to RXU (69%) with statistically significant differences between RXU vs. SB-E (p = 0.022) and RXU vs. SB+E (p ≤ 0.001). Conclusions After 39-months, PCCs luted with the self-adhesive resin cement exhibited a statistically significant inferior survival rate compared to restorations luted with the conventional resin cement combined with a universal adhesive without or with selective enamel etching. Clinical significance Currently, self-adhesive resin cements cannot be recommended for luting partial ceramic crowns. However, the standard adhesive luting procedure comprising a universal adhesive and luting composite yielded good clinical results for more than 3 years irrespectively of application of a selective enamel etching step.

A prospective clinical pilot study on the effects of a hydrogen peroxide mouthrinse on the intraoral viral load of SARS-CoV-2.

OBJECTIVES: SARS-CoV-2 is mainly transmitted by inhalation of droplets and aerosols. This puts healthcare professionals from specialties with close patient contact at high risk of nosocomial infections with SARS-CoV-2. In this context, preprocedural mouthrinses with hydrogen peroxide have been recommended before conducting intraoral procedures. Therefore, the aim of this study was to investigate the effects of a 1% hydrogen peroxide mouthrinse on reducing the intraoral SARS-CoV-2 load. METHODS: Twelve out of 98 initially screened hospitalized SARS-CoV-2-positive patients were included in this study. Intraoral viral load was determined by RT-PCR at baseline, whereupon patients had to gargle mouth and throat with 20 mL of 1% hydrogen peroxide for 30 s. After 30 min, a second examination of intraoral viral load was performed by RT-PCR. Furthermore, virus culture was performed for specimens exhibiting viral load of at least 103 RNA copies/mL at baseline. RESULTS: Ten out of the 12 initially included SARS-CoV-2-positive patients completed the study. The hydrogen peroxide mouthrinse led to no significant reduction of intraoral viral load. Replicating virus could only be determined from one baseline specimen. CONCLUSION: A 1% hydrogen peroxide mouthrinse does not reduce the intraoral viral load in SARS-CoV-2-positive subjects. However, virus culture did not yield any indication on the effects of the mouthrinse on the infectivity of the detected RNA copies. CLINICAL RELEVANCE: The recommendation of a preprocedural mouthrinse with hydrogen peroxide before intraoral procedures is questionable and thus should not be supported any longer, but strict infection prevention regimens are of paramount importance. TRIAL REGISTRATION: German Clinical Trials Register (ref. DRKS00022484).

Influence of selective caries excavation on marginal penetration of class II composite restorations in vitro.

Selective caries excavation may support pulp preservation. This in vitro study investigated the influence of selective removal of demineralized dentin on marginal integrity of composite restorations as determined by dye penetration. Dentinal caries-like lesions were produced in the approximal surfaces of 40 extracted human molars (ethylenediaminetetraacetate, 0.5 M, 96 h). The following test procedures were established: complete excavation, selective excavation, and caries-free control. Two class II cavities with enamel at the cervical margins were prepared per tooth and demineralization volume was determined by micro-computed tomography for the purpose of a stratified distribution to receive complete excavation or selective excavation. After complete or selective excavation (30 cavities each), adhesive composite restorations were placed. Cavities without demineralized dentin (20 cavities) served as control. The marginal integrity of restorations was evaluated by dye penetration with and without thermocycling or mechanical loading. Results were analyzed by non-parametrical statistical tests (Mann-Whitney U Test) with an α = 0.05 level of significance. Dye penetration did not differ significantly among completely excavated, selectively excavated, or undemineralized teeth, but was increased by thermocycling and mechanical loading in all experimental groups. Selective caries removal did not increase marginal penetration in class II restorations. The presence of remaining demineralized dentin surrounded by sound dentin did not impair marginal integrity of restorations with margins placed in sound enamel.

Monolithic Polymer-Infiltrated Ceramic Network CAD/CAM Single Crowns: Three-Year Mid-Term Results of a Prospective Clinical Study.

PURPOSE: To evaluate the clinical outcomes of monolithic CAD/CAM-fabricated polymer-infiltrated ceramic network (PICN) single crowns (SC) after 3 years. MATERIALS AND METHODS: A total of 34 patients who received 76 single crowns were included in this cohort study. Full-coverage crown preparation with reduced thickness (1.0 to 1.5 mm) was applied. All monolithic PICN SCs (VITA Enamic) were manufactured using a CAD/CAM system and adhesively seated. Clinical follow-up evaluations were performed at 6, 12, 24, and 36 months after insertion using modified United States Public Health Service (USPHS) criteria. Kaplan-Meier survival and success methods were applied to calculate absolute and relative failures. To determine effects of time and restoration, a mixed logit model was adjusted for the modified USPHS criteria (P < .05). RESULTS: PICN SCs revealed an estimated Kaplan-Meier survival rate of 93.9% after 3 years. Four clinically unacceptable fractures occurred, which resulted in replacement of the affected SCs. Neither secondary caries nor debonding were recorded. The 3-year Kaplan-Meier success rate was 92.7%. Significant increases in marginal discoloration (P = .0002) and surface roughness (P < .0001) were noted over time. Color match, anatomical form, and marginal adaptation remained favorable over the given observation period. CONCLUSION: PICN CAD/CAM crowns with reduced thickness showed acceptable survival and success rates over a service time of 36 months. However, extended clinical follow-up periods are needed to evaluate the long-term performance.

Flowable composites for restoration of non-carious cervical lesions: Results after five years.

OBJECTIVES: To evaluate the clinical performance of two flowable composites for restoration of Class-V non-carious cervical lesions (NCCLs), one with novel (N'Durance® Dimer Flow, Septodont; ND) and one with modified conventional matrix composition (Filtek™ Supreme XTE Flow, 3M-ESPE; FS). The null hypothesis was that both flowable composite materials perform equally regarding clinical quality and survival. METHODS: 50 patients received one ND and one FS restoration of NCCLs in premolars using Clearfil Protect Bond (Kuraray) as an adhesive without additional selective enamel etching. Restorations were evaluated at baseline (BL), after 30 and 60 months employing selected original FDI criteria and refined FDI criteria by separate evaluation of enamel and dentine margins. Non-parametric statistical analyses and χ2 tests were applied (α=0.05). RESULTS: 38 patients with both restorations under risk were available for the 60-mo recall (recall rate: 76%). At 60-mo, 94.7% of ND and 84.2% of FS restorations were rated clinically acceptable. No significant differences for all selected FDI criteria were recorded between ND and FS at each examination time point except for the criteria surface lustre at 60-mo, where FS showed significantly better results. No significant differences over time could be detected for both materials. There was a trend for more deterioration along the enamel margins than along the dentine margins (criteria marginal staining and marginal adaptation). SIGNIFICANCE: Within the limitations of the study, the null hypothesis that materials perform equally could not be rejected. Both flowable composites performed similarly regarding clinical performance.