Effects of glass ionomer and microfilled composite subgingival restorations on periodontal tissue and subgingival biofilm: a 6-month evaluation

Evaluation of a novel restorative protocol to treat non-carious cervical lesion associated with gingival recession: a 2-year follow-up randomized clinical trial

OBJECTIVE

To compare 2 different resin composites and 2 adhesive systems used in a new restorative protocol (partial restoration) to treat non-carious cervical lesions associated with gingival recession type 1 (RT1).

MATERIAL AND METHODS

Eighty combined defects (CDs) were treated with a partial restoration and periodontal plastic surgery for root coverage. The CDs were randomly assigned to one of the following groups: NP + TE (n = 20), nanofilled composite and 2-step total-etch adhesive system; NP + UA (n = 20), nanofilled composite and universal adhesive system; MH + TE (n = 20), microhybrid composite and 2-step total-etch adhesive; MH + UA (n = 20), microhybrid composite and universal adhesive. Restorations were assessed using the United States Public Health Service (USPHS) criteria at 1 week (baseline) and 6, 12, and 24 months. Survival rate, periodontal parameters, dentin hypersensitivity (DH), and aesthetics were also evaluated.

RESULTS

After 24 months, only the MH + TE group did not lose any restoration, with no significant differences between groups. For surface roughness parameter, MH presented 83.3% of the restorations scoring Bravo, whereas NP presented 48.5% of the restorations scoring Bravo. All groups presented restorations with marginal discoloration. All periodontal parameters behaved similarly, regardless of the restorative material. All groups presented significant reductions of dentin hypersensitivity and improved aesthetic perceptions (p < 0.05).

CONCLUSION

Both resin composites and adhesives tested can be combined for partial restorations to treat CDs.

CLINICAL RELEVANCE

This new restorative-surgical protocol to treat CDs presents satisfactory outcomes. The partial restorations can be successfully executed with both combinations of adhesives and resin composites evaluated in this investigation. TRN : ClinicalTrial.gov: NCT03215615; registration date July 12, 2017.

Evaluation of the clinical performance of GIOMERs and comparison with other conventional restorative materials in permanent teeth: a systematic review and meta-analysis

Aim The aim of this systematic review and meta-analysis was to analyse the clinical performance of GIOMER restorative composites and compare them with other conventional restorative materials in permanent teeth.Methods Searches in PubMed, Web of Science, Scopus, Ovid and Cochrane Library were conducted. Grey literature search was also performed. Clinical trials that evaluated the clinical performance of restorations with GIOMER restorative composites in permanent teeth compared to those using composite resin, glass ionomer cement, resin-modified glass ionomer cement (RMGIC) and other GIOMERs were included. Meta-analyses comparing GIOMER restorative composites with RMGIC at 6- and 12-month follow-ups and comparing two types of GIOMER were feasible.Results Ten studies fulfilled the inclusion criteria. In these studies, GIOMER was compared to different types of dental restoration materials. Dental restorations were evaluated by United States Public Health Service criteria in all included studies. Four studies were suitable for meta-analysis, which showed significant differences between GIOMER and RMGIC surface roughness at 6-month (odds ratio [OR] = 6.56; 95% confidence interval [CI] = 2.38-18.13) and 12-month (OR = 8.76; CI = 3.19-24.07) follow-ups. No significant differences between GIOMER restorative composites and RMGIC for marginal adaptation were found at 6- and 12-month follow-ups. When comparing two GIOMERs, significant differences were seen between Beautifil II and Beautifil Flowable Plus F00 for marginal staining (OR = 2.58; CI = 1.42-23.27; I2 = 0%) and surface roughness (OR = 4.59; CI = 1.11-18.97; I2 = 0%) at the 36-month follow-up. No significant differences between Beautifil II and Beautifil Flowable Plus F00 were seen for marginal adaptation and anatomic form at 6-, 18- and 36-month follow-ups.Conclusions GIOMER restorative composites presented similar performance concerning marginal adaptation and better surface roughness when compared to RMGIC. GIOMER Beautifil II presented similar performance to GIOMER Beautifil Flow Plus F00 concerning marginal adaptation and anatomic form and worse marginal staining and surface roughness when compared to Beautifil Flowable Plus F00.

Deep Margin Elevation: A Literature Review

A conservative approach for restoring deep proximal lesions is to apply an increment of composite resin over the preexisting cervical margin to relocate it coronally, the so-called “deep margin elevation” (DME). A literature search for research articles referring to DME published from January 1998 until November 2021 was conducted using MEDLINE (PubMed), Ovid, Scopus, Cochrane Library and Semantic Scholar databases applying preset inclusion and exclusion criteria. Elevation material and adhesive system employed for luting seem to be significant factors concerning the marginal adaptation of the restoration. This technique does not affect bond strength, fatigue behavior, fracture resistance, failure pattern or repairability. DME and subgingival restorations are compatible with periodontal health, given that they are well-polished and refined. The available literature is limited mainly to in vitro studies. Therefore, randomized clinical trials with extended follow-up periods are necessary to clarify all aspects of the technique and ascertain its validity in clinical practice. For the time being, DME should be applied with caution respecting three criteria: capability of field isolation, the perfect seal of the cervical margin provided by the matrix, and no invasion of the connective compartment of biological width.

Survival of atraumatic restorative treatment restorations in the elderly patients: a systematic review

This study aimed to assess the survival of glass ionomer cement (GIC) restorations performed using the atraumatic restorative treatment (ART) in elderly patients. The systematic review protocol was registered in the PROSPERO database. The records were searched until August 2020 in eight electronic bibliographic databases, and included randomized and non-randomized clinical trials and observational studies, with no restrictions on the language or year of publication. Study selection and data extraction were performed independently by two reviewers. Data were extracted, summarized, collected for qualitative analysis, and evaluated for individual risk of bias using the Joanna Briggs Institute's Critical Appraisal Tool. The literature search retrieved 5,186 records; however, only seven studies fulfilled the eligibility criteria and were included. The studies were published between 2002 and 2019. A total of 1,239 restorations were investigated at intervals of 6, 12, 24, and 60 months of follow-up. Some studies had a low risk of bias, while others had moderate and high risk of bias. In general, GIC restorations placed using ART were considered satisfactory. The 6-month, 12-month, and 24-month survival rates ranged from 81.3% to 97.2%, 72.2% to 94%, and 63% to 87%, respectively; additionally, the survival rate for the longest follow-up period (60 months) was 85%. Given the best evidence-based information regarding caries removal, we highlight the need to provide a conservative and effective technique for use in elderly patients. ART is a promising and viable alternative that guarantees the survival of restorations in elderly patients.

Application of Texture and Fractal Dimension Analysis to Evaluate Subgingival Cement Surfaces in Terms of Biocompatibility

Biocompatibility is defined as “the ability of a biomaterial, prosthesis, or medical device to perform with an appropriate host response in a specific application”. Biocompatibility is especially important for restorative dentists as they use materials that remain in close contact with living tissues for a long time. The research material involves six types of cement used frequently in the subgingival region: Ketac Fil Plus (3M ESPE, Germany), Riva Self Cure (SDI, Australia) (Glass Ionomer Cements), Breeze (Pentron Clinical, USA) (Resin-based Cement), Adhesor Carbofine (Pentron, Czech Republic), Harvard Polycarboxylat Cement (Harvard Dental, Great Britain) (Zinc polycarboxylate types of cement) and Agatos S (Chema-Elektromet, Poland) (Zinc Phosphate Cement). Texture and fractal dimension analysis was applied. An evaluation of cytotoxicity and cell adhesion was carried out. The fractal dimension of Breeze (Pentron Clinical, USA) differed in each of the tested types of cement. Adhesor Carbofine (Pentron, Czech Republic) cytotoxicity was rated 4 on a 0–4 scale. The Ketac Fil Plus (3M ESPE, Germany) and Riva Self Cure (SDI, Australia) cements showed the most favorable conditions for the adhesion of fibroblasts, despite statistically significant differences in the fractal dimension of their surfaces.

Rethinking the decision-making process to treat gingival recession associated with non-carious cervical lesions

The presence of a tooth-surface defect, such as a non-carious cervical lesion (NCCL), associated with sites of gingival recession (GR) defects creates a combined soft tissue/tooth defect (CD) that requires a different treatment plan. This study aimed to critically review the literature regarding the available treatment protocols for CDs and suggest a new decision-making process. NCCLs were classified as Class A-: the cementoenamel junction (CEJ) was visible and the root surface discrepancy was < 0.5 mm (no step); Class A+: CEJ was visible and the root surface discrepancy was > 0.5 mm (with a step); Class B-: unidentifiable CEJ without a step; Class B+: unidentifiable CEJ with a step. NCCLs affecting both root and crown surfaces (Class B) lead to CEJ destruction and consequently eliminate an important landmark used before and after root coverage procedures. The depth of the root surface discrepancy is vital owing to its possible impact on soft tissue adaptation after healing, which, in turn, may influence the treatment options, namely the use of graft and/or composites to compensate for the discrepancy. Clinically, a step with horizontal depth greater than 0.5 mm should be recognized as the minimum threshold value to define this condition. Extremely deep defects tend to assume a V-shaped topography. Therefore, extremely deep V-shaped defects were classified into subclasses A+V, a V-shaped defect, and B+V, a V-shaped defect with loss of CEJ, for management considerations. The treatment options, supported by the literature, and a decision-making process to deal with each condition are presented.

In Vitro Study on the Adhesive Performance of Some Resin-Based Materials Used to Restore Class II Cavities

The study aimed to evaluate the adhesive performances of two ormocer materials and two micro-hybrid composites placed to restore class II cavities. We tested the null hypothesis, which considered that the adhesive behaviors of tested materials did not differ. On each extracted tooth, two class II cavities were prepared having an enamel located cervical margin and a cementum located cervical margin, respectively, and were restored using two different restoration techniques. The teeth followed a tooth impregnating protocol and were sectioned and evaluated by optical microscopy to highlight the marginal microleakage around restorations. Cervical and occlusal microleakage as well as microleakage ratios were calculated. The microleakage test showed that all tested materials exhibited some degree of dentinal microleakage both on cervical and occlusal areas irrespective of the restoration technique. Some significant differences were recorded in adhesion performance of the materials. The cervical microleakage ratio was significantly increased for one of the micro-hybrid resin composites in comparison with one of the ormocer materials (p = 0.0159). Significantly differences were observed in occlusal microleakage ratios when the two micro-hybrid composites were compared (p = 0.047). The results failed to reject the null hypothesis. The present study could not demonstrate the superiority of ormocer-materials relative to conventional composites.

Cytotoxicity of Different Composite Resins on Human Gingival Fibroblast Cell Lines

The aim of the present study was to evaluate and compare the cytotoxic effects of eight composite resins on immortalized human gingival fibroblasts. Composite resins were eluted in cell culture medium for 48 or 72 h at 37 °C. Immortalized human gingival fibroblast-1 (HGF-1) cell lines were seeded in 96-well (1 × 10⁴) plates and incubated for 24 h at 37 °C with the obtained extraction medium. The percentage of viable cells in each well (MTT test) was calculated relative to control cells, which were set to 100%. Data observed were not normally distributed, and nonparametric statistical methods were used for statistical analysis. The Wilcoxon test was used for intragroup comparison, and the Kruskal–Wallis test was used for intergroup multiple comparisons. Significance value was set as p < 0.05. All materials tested showed cytotoxic effects on gingival fibroblasts, recordable as noncytotoxic, mildly cytotoxic or severely cytotoxic, depending on the percentage of cell viability. The Wilcoxon test for intragroup comparison showed that the percentage of viable cells decreased significantly for extracts, for all composite resins tested. The composite resins contained monomers that displayed cytotoxic properties. BisGMA, TEGDMA and UDMA had inhibitory effects and induced apoptotic proteins in pulp fibroblast. Composite resins that contained lower percentages of unbound free monomers—and that released less ions—possessed superior biocompatibility in vitro.

Periodontal response to a tricalcium silicate material or resin composite placed in close contact to the supracrestal tissue attachment: a histomorphometric comparative study

OBJECTIVE

Subgingival dental restorations and periodontal health have been studied for many years; however, there is a low histological evidence on the behavior of new materials in the supracrestal tissue attachment. The aim of this study is to analyze the periodontal response when a tricalcium silicate material (TSM) or composite margin restorations is placed to 0.5 mm and 1.5 mm from the bone crest with a histomorphometric analysis in dogs.

METHODS

Nine mongrel dogs were used in this study: four dogs (8 canine teeth) for TSM group, 4 dogs (8 canine teeth) for composite group, and 1 dog (2 canine teeth) with cavities without restorations. Cavity preparation of 2×2×1 mm was created on the buccal aspect of the canines at 0.5 and 1.5 mm of the crestal bone. Cavities were restored with composite and TSM or were left unrestored as control. After 12 weeks of healing, the dogs were euthanized and blocks containing the tooth and soft tissues were processed.

RESULTS

In all the specimens, the junction epithelium was stablished apical to the tooth preparations. A shorter distance to the bone (0.5 cavity) implies greater apical periodontal migration regardless of the material used. In the TSM groups, the connective tissue height and the distance between bone level and apical margin preparation were greater than those in the composite groups, while the epithelium height was less. However, there were no statistically significant differences comparing TSM and composite groups at either 0.5 mm or 1.5 mm (p > 0.05).

CONCLUSION

Histologic analysis did not show periodontal reattachment to TSM or composite. In both cases, bone crest migrates apically. For that reason, it is recommended to perform composite restorations at the subgingival level whenever the distance to the bone crest is at least 2 mm.

CLINICAL RELEVANCE

Both composite and TSM do not achieve reinsertion of the connective tissue in the biological width.

Treatment efficacy of gingival recession defects associated with non-carious cervical lesions: a systematic review

Purpose

This systematic review aimed to compare the efficacy, defined in terms of the mean percentage of root coverage (mRC), of surgical treatment approaches combined with adhesive restorations of non-carious cervical lesions (NCCLs) to that of root coverage alone in patients with a single gingival recession (GR) and NCCL.

Methods

A literature search was conducted to identify longitudinal studies reporting the mRC following treatment for the correction of GR defects associated with NCCLs using a combination of surgical and restorative techniques in systemically and periodontally healthy patients.

Results

The search resulted in the retrieval of 12,409 records. Seven publications met the inclusion criteria for the qualitative synthesis of data. The mRCs ranged from 69% to 97%. In the medium term, the gingival margin position was more stable when a connective tissue graft (CTG) was used, independently of whether restoration of teeth with NCCLs was performed.

Conclusions

The strength of the evidence was limited by methodological heterogeneity in terms of study design as well as the unit and period of analysis, which precluded a meta-analysis. Although no definitive conclusion could be drawn due to the lack of sufficient evidence to estimate the effectiveness of the interventions, CTG-based procedures contributed to gingival margin stability regardless of the performance of restoration to treat NCCLs.

The Relationships Between Tooth-Supported Fixed Dental Prostheses and Restorations and the Periodontium

PURPOSE

To search the literature and to critically evaluate the findings on the periodontal outcomes of restorations and tooth-supported fixed prostheses.

MATERIALS AND METHODS

PubMed was searched according to a systematic methodology, previously reported, but updated to include a larger database. Filters applied were: Case reports, clinical trial, review, guideline, randomized controlled trial, meta-analysis, systematic reviews, and English. A narrative review was then synthesized to discuss periodontal outcomes related to restorations and tooth-supported fixed prostheses. Relevant data was organized into four sections: Direct restorations, indirect restorations, biologic width or supracrestal tissue attachment and tooth preparation/finish line design.

RESULTS

While increased gingival index, bleeding on probing, probing depth and clinical attachment loss have been associated with subgingival restorations, intracrevicular margins do not cause periodontal diseases. Inflammation and bone loss occur, for both direct and indirect restorations, only with large overhangs. Different restorative materials are associated with different clinical responses when placed in the gingival sulcus or within the epithelial and connective tissue attachments. When the connective tissue attachment is removed, histological changes occur causing its apical shift and subsequent re-establishment. Gingival displacement during impression procedures can cause gingival recession. Emergence profile can have a range of values, not associated with periodontal diseases. Periodontal response appears to be clinically not different when compared among different finish line designs.

CONCLUSIONS

Contemporary procedures and materials used for the placement and fabrication of tooth-supported restorations and fixed prostheses are compatible with periodontal health when adequate patient education and motivation in self-performed oral hygiene are present. Periodontal diagnostic criteria should be thoroughly reviewed before fixed restorative treatments are planned and executed.

Cytotoxicity of Different Nano Composite Resins on Human Gingival and Periodontal Ligament Fibroblast Cell Lines: An In Vitro Study

The aim of this study is to determine the cytotoxicity of three different nano composite resins (CRs) on human gingival fibroblast (hGF) and periodontal ligament fibroblast (hPDLF) cell lines. These CRs selected were nanohybrid organic monomer-based Admira Fusion (AF), nanohybrid Bis-(acryloyloxymethyl) tricyclo [5.2.1.0.sup.2,6] decane-based Charisma Topaz (CT), and supra nano filled resin-based Estelite Quick Sigma (EQS). MTT assay was performed to assess the cytotoxicity of CRs at 24 h and one week. AF and EQS applied on hGF cells at 24 h and one week demonstrated similar cytotoxic outcomes. Cytotoxicity of CT on hGF cells at one week was higher than 24 h (p = 0.04). Cytotoxicity of CT on hGF cells was higher at 24 h (p = 0.002) and one week (p = 0.009) compared to control. All composites showed higher cytotoxicity on hPDLF cells at one week than the 24 h (AF; p = 0.02, CT; p = 0.02, EQS; p = 0.04). AF and EQS demonstrated lower cytotoxicity on hPDLF cells than the control group at 24 h (AF; p = 0.01, EQS; p = 0.001). CT was found more cytotoxic on hPDLF cells than the control (p = 0.01) and EQS group (p = 0.008) at one week. The cytotoxicity of CRs on hGF and hPDLF cells vary, according to the type of composites, cell types, and exposure time.

Experimental and clinical studies on plastic periodontal procedures

We have compiled, in this Periodontology 2000 review, all Latin American literature on experimental and clinical studies of periodontal plastic procedures. The body of literature on this subject has led to a discussion of the features and treatment outcomes of root-coverage procedures. Over time, knowledge on periodontal plastic procedures has become less empirical and more supportive of the clinical management of recession-type defects. Gingival recession etiology, animal studies, free gingival grafts, pedicle flaps (semilunar, laterally positioned, and coronally positioned), and subepithelial connective tissue grafts are extensively reviewed. The use of allografts as an alternative to subepithelial connective tissue grafts, the treatment of multiple gingival recessions, and the rationale for use of guided tissue regeneration and enamel matrix derivative in plastic periodontal procedure is discussed. We also assess how smoking can affect the treatment outcomes in plastic surgery procedures. Minimally invasive procedures are of great value in improving the features of the final tissues. The following aspects identified in this compilation were of great interest: (a) some factors, anatomical in nature, favor the formation of root recessions, but it is the inflammatory process (caused by the presence of biofilm and/or by traumatic toothbrushing) that is responsible for the development of root recessions; and (b) pedicle flap procedures (especially the coronally positioned flap) are extremely versatile and have the most predictable outcome of all root-coverage procedures, especially when combined with subepithelial connective tissue grafting and/or allogeneic grafts. In summary: subepithelial connective tissue grafting is considered as the first option to augment gingival width and thickness, and it may provide better long-term results; the same principles of root-coverage procedures in individual sites appear be used in clinical practice also for multiple-recession type defects; an allograft is an efficient alternative to a subepithelial connective tissue graft and, when it is the treatment option of choice, the use of wide, extended flaps should be considered; because of the superiority of plastic periodontal procedures over guided tissue regeneration and the technical difficulty of the latter, guided tissue regeneration has become obsolete for root-coverage procedures; there is rather a large body of evidence attesting that smoking negatively influences root-coverage procedures, especially subepithelial connective tissue grafts; and minimally invasive techniques may be of great value for improving the results obtained with plastic periodontal procedures, but these techniques need to be better addressed in clinical trials, both in terms of the quality and quantity of the new tissue generated.

Clinical and histological reaction of periodontal tissues to subgingival resin composite restorations

OBJECTIVES

To compare the clinical and histological response of supracrestal periodontal tissues to subgingival composite restorations versus natural root surfaces MATERIAL AND METHODS: In 29 subjects with a single tooth requiring subgingival restorations, a deep margin elevation (DME) procedure with composite resin was applied. Full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), and focal probing depth (PD) were measured at baseline, before DME, and after 3 months. The distance between the coronal marked (CM) point to the apical margin of the composite reconstruction (AMR), at baseline, and to the tip of the periodontal probe inserted to reach the bottom of the sulcus (APP), 3 months later, was measured. An all-around secondary flap, harvested to ensure the subsequent single-crown prosthetic rehabilitation was histologically processed. The histological inflammation degree was evaluated in areas of gingival tissues adjacent to the composite (group B) and adjacent to the natural surface of each single tooth (group A).

RESULTS

Significant FMPS, FMBS, and PD decreases were observed (p < 0.05). CM-AMR and CM-APP were significantly different (p < 0.05), suggesting an attachment gain after 3-months. The inflammation level of gingival tissue was similar in groups A and B (p > 0.05).

CONCLUSIONS

For the first time, this topic was clinically and histologically studied in humans. Subgingival restorations resulted compatible with gingival health, with levels similar to that of untreated root surfaces.

CLINICAL RELEVANCE

Deep margin elevation procedure produces favorable clinical and histological outcomes allowing a routine utilization in reconstructive dentistry.

Clinical evaluation of combined surgical/ restorative treatment of gingival recession-type defects using different restorative materials: A randomized clinical trial

Background/purpose

An ideal therapeutic procedure for the treatment of gingival recession associated with an NCCL has presented a challenge to clinicians. Various dental materials and surgical approaches have been used to manage gingival recessions associated with NCCLs for the most predictable combined surgical/restorative treatment. The objective of this study was to evaluate the treatment of gingival recessions associated with non-carious cervical lesions (NCCL) using a modified coronally advanced flap (MCAF) in combination with a connective tissue graft (CTG) on restored root surfaces.

Materials and methods

Twenty-three systemically healthy subjects, who were positive for the presence of three cervical lesions associated with gingival recessions in three different adjacent teeth, were enrolled in the study. The NCCL were each restored prior to surgery by using one of three different materials: nanofilled composite resin (NCR), resin-modified glass ionomer cement (RMGI) or giomer. The gingival recession defects were treated by CTG.

Results

Inter-group differences were not statistically significant for probing depth (PD), relative recession height (rRH), relative clinical attachment level (rCAL), keratinized tissue width (KTW) or keratinized tissue thickness (KTT) (p > 0.05) among the groups at any time. The mean percentage of defect coverage was 71.18 ± 23.16% for NCR + CTG group; 71.33 ± 22.33% for RMGI + CTG group; and 64.23 ± 20.33% for giomer + CTG group at 1 year postoperatively (p > 0.05).

Conclusion

The combined surgical/restorative treatments provided successful clinical results. Giomer + CTG may be less effective compared to other groups for treatment of gingival recession associated with NCCL.

Gingival tissue reaction to direct adhesive restoration: A preliminary study

INTRODUCTION

It is debated whether composite resin marginal/submarginal direct restoration can be usefully performed without inflammatory consequences. This histological study is the first human analysis aimed to compare, in the same tooth, the gingival tissue close to composite resin restorations with gingival tissue close to hard tissue.

METHODS

Eight healthy patients with almost a residual strategic tooth needing endodontic therapy, and post-and-core restoration, then indirect prosthetic restoration, were selected. Direct margin relocation with composite resin was necessary to perform endodontic treatment. The crown lengthening with a secondary flap harvested was necessary to perform prosthetic rehabilitation. Three months after marginal relocation, the secondary flap was harvested, embedded in PMMA, 4-μm sectioned, and stained to analyze the inflammation degree.

RESULTS

All patients completed post-and-core reconstruction and the planned prosthetic therapy, maintaining the stringent hygienic protocol plan. The inflammation level comparison, slightly lower in gingiva close to the teeth (3.62 ± 0.38) than in gingiva close to the composite (3.75 ± 0.26), results in a p-value of 0.11 after Wilcoxon test.

CONCLUSIONS

Results highlight a minimal, statistically not significant difference in the inflammation degree after margin relocation, conceivably due to patients, teeth and cases selection, together with adopted stringent methodological and supportive measures.

The effects of different restorative materials on periodontopathogens in combined restorative-periodontal treatment

Objective

The aim of the study was to evaluate the association between subgingival restorations and the target periodontopathogenic bacteria (Pg, Td and Pi) in subgingival biofilm during one year after combined restorative-periodontal treatment.

Material and Methods

Seventeen systemically healthy subjects, who were positive for the presence of three cervical lesions associated with gingival recessions in three different adjacent teeth, were included in the study. A total of 51 combined defects were treated with connective tissue graft plus a nanofilled composite resin (NCR+CTG), a resin-modified glass ionemer cement (RMGI+CTG) and a fluoride-releasing resin material with pre-reacted glass (PRG), called giomer (Giomer+CTG). Periodontal clinical measurements and subgingival plaque samples were obtained from all combined defects at baseline and at 6 and 12 months after the surgery. The number of bacteria were evaluated by the real-time polymerase chain reaction (qPCR) method.

Results

No statistically significant difference in the amount of DNA copies of Pg, Td and Pi was observed in any of the groups at any time points (p>0.05). In addition, there was no statistically significant difference in the amount of DNA copies of the bacteria at baseline and at 6 and 12 months postoperatively, regardless of treatment group (p>0.05).

Conclusion

This study suggests that subgingivally placed NCR, RMGI and giomer restorations can show similar effects on periodontopathogenic bacteria in the treatment of gingival recessions that are associated with noncarious cervical lesions (NCCLs).

Does Evidence Support a Combined Restorative Surgical Approach for the Treatment of Gingival Recessions Associated With Noncarious Cervical Lesions?

OBJECTIVES

Gingival recessions are frequently associated with noncarious cervical lesions. Combined restorative surgical approaches have been suggested for the management of these combined defects. The aim of this review was to analyze the current evidence on the effectiveness of these combined restorative surgical approaches.

METHODS

A systematic review of randomized controlled studies published from January 2006 to June 2016 was performed.

RESULTS

Ten articles comparing combined restorative surgical approaches to surgery alone were included. Both the procedures showed similar outcomes in term of root coverage but the combined restorative surgical approach achieved better result in the reduction of dentin hypersensitivity. In combined restorative surgical treatments, resin-modified glass ionomers showed better antimicrobial properties but poorer esthetic outcome than resin composites.

CONCLUSION

Data to support or refute definitely the interest of combined approaches for the treatment of gingival recessions associated with noncarious cervical lesions are limited.

Stress-strain Analysis of Premolars With Non-carious Cervical Lesions: Influence of Restorative Material, Loading Direction and Mechanical Fatigue

Noncarious cervical lesions (NCCLs) are characterized by a loss of dental structure at the cementoenamel junction (CEJ) caused by stress, biocorrosion, and attrition. Variations in occlusal loading can promote different stress and strain patterns on the CEJ. Restoration of NCCLs is part of lesion management; however, there is still no conclusive restorative protocol for NCCLs. This study aimed to evaluate the stress and strain distribution of maxillary premolars with NCCLs according to three factors: 1) restorative technique; 2) direction of occlusal loading; and 3) mechanical fatigue. Three-dimensional (3D) finite element analysis (FEA) and strain gauge testing were used to assess stress and strain, respectively. 3D-FEA orthotropic, linear, and elastic models were generated: sound tooth (SO); unrestored NCCL; or NCCL restored with glass ionomer; flowable composite resin; nanofilled composite resin (CR); lithium disilicate ceramic; and nanofilled composite resin core associated with a lithium disilicate laminate (CL). A 150-N compressive static load was applied in two conditions: axially in both cusps (Al); and at a 45° angle to the long axis of the tooth applied to the palatine cusp (Ol). For the experimental tests, specimens were treated as described previously, and one strain gauge was attached to the buccal surface of each tooth to record tooth strains before and after cyclic loading (200,000 cycles, 50 N). FEA showed that the association of NCCL and Ol resulted in higher stress values. CR and CL restorations showed the closest biomechanical behavior to SO for both loading types. Loaded Al or Ol specimens showed higher strain values after mechanical fatigue. Lower stress and strain were observed with Al when compared with Ol. The restoration of NCCLs with composite resin only or associated with ceramic laminates seems to be the best approach because the results for those groups were similar in biomechanical behaviors to sound teeth.

Root coverage in an HIV-positive individual: combined use of a lateral sliding flap and resin-modified glass ionomer for the management of an isolated severe recession defect

BACKGROUND

Gingival recession is a frequent clinical finding in the general population. Exposed root surfaces are more likely to develop root sensitivity and root caries and pose esthetic concerns for the patient. Most root coverage procedures have been described on non-restored root surfaces. Limited data are available that describe root coverage procedures on restored root surfaces. To our knowledge, this is the first case report in which a severe recession defect and its associated carious lesion were managed using the combination of a lateral sliding flap and a resin-modified glass ionomer restoration in an HIV-positive individual.

METHODS

A 53-year-old male patient with a 25-year history of HIV infection presented for comprehensive care. The facial surface of tooth #22 had a fractured composite restoration, recurrent decay, and a Miller Class III recession defect. The lesion was restored with resin-modified glass ionomer and root coverage was obtained by a lateral sliding flap mobilized from the adjacent edentulous ridge. After 8 weeks, surgical access was used to correct a previously undetected void in the restoration.

RESULTS

Uneventful healing was observed at the 1-, 4-, 8-, 10-, 12-, and 24-week postoperative visits. Root coverage of 5 mm along with a 2-mm band of keratinized tissue was obtained at 24 weeks. The gingiva displayed no signs of inflammation and was tightly adapted to the root surface with minimal probing depths circumferentially.

CONCLUSION

Successful root coverage was obtained on a resin-modified glass ionomer-restored surface in an HIV-positive individual.