Composite Resin Restorations Research Articles

The treatment options for the traumatically fractured tooth; Case reports

The traumatic accident could cause various damages to the teeth and surrounding tissues. It makes dentist embarrass be-cause it not only requires the dentist to make quick decision, but also delayed decision affect the prognosis of the treatment. Depending on the location of the fracture, the fractured teeth are divided into crown fracture without pulpal involvement (Uncomplicated crown fracture), crown fracture with pulpal involvement (Complicated crown fracture), crown-root frac-ture, and root fracture. When the crown was fractured, treatment was performed with reattachment of the fragment or direct composite resin restoration depending on the presence or absence of the crown fragment. In the case of crown-root fracture, the direction of treatment can be set depending on whether the moisture control for final restoration is properly performed. In the case of root fracture, follow-up was observed after fixation using resin wire splint fixation, and if necessary, endodontic treatment of the crown fragment is recommended. The cases reported here have led to positive treatment outcome in fractured tooth for various traumatized situation.

A Minimally Invasive Esthetic Approach for Teeth with Molar Incisor Hypomineralization: a Clinical Case Report

Molar incisor hypomineralization (MIH) is a qualitative defect of enamel, clinically characterized by white or yellow/brownish demarcated opacities that affect permanent molars, often associated with permanent incisors. The etiology is multifactorial, including systemic and genetic/epigenetic factors. Defects of anterior teeth can negatively impact children since they might present lower self-esteem and socialization problems. Purpose: To describe a minimally invasive treatment for anterior teeth affected by molar incisor hypomineralization, performed with direct composite resin restoration and a universal adhesive system. Case Report: An 8-year-old patient sought dental care with complaints about her dental appearance, reporting suffering from school bullying. She presented a white-yellowish opacity on the maxillary right central incisor. After a clinical examination, she was diagnosed with molar incisor hypomineralization. To improve dental esthetics, a direct composite resin restoration was proposed. The enamel surface was prepared and etched with 35% phosphoric acid etchant solution for 15 seconds before applying the universal adhesive system. Two different shades of the composite were used for layering the material to disguise the defect without extensive removal of the dental structure. The result was satisfactory as it was possible to mask the opacity, reestablish enamel thickness, and improve the patient's quality of life. Conclusion: Conservative restorations comprising a universal adhesive system seem to bring desirable esthetic results for anterior teeth with molar incisor hypomineralization.

Longevity of composite resin restorations: an unceasing quest

Longevity of composite resin restorations: an unceasing quest

Internal Adaptation of Composite Fillings Made Using Universal Adhesives-A Micro-Computed Tomography Analysis.

This study aimed to evaluate internal tooth-filling interfaces of composite fillings made using universal adhesives using micro-computed tomography (µCT). Sixty class V cavities were randomly assigned into six groups: Peak Universal etch and rinse (PER), Peak Universal self-etch (PSE), Adhese Universal etch and rinse (AER), and Adhese Universal self-etch (ASE). Two further adhesives considered gold standards were used as control groups: OptiBond FL (OER) for the etch and rinse technique and Clearfil SE for the self-etch technique (CSE). All teeth were subjected to thermomechanical loading and four-year water storage. Next, they were analyzed using µCT to investigate the internal tooth-filling interfaces. The proportions between the gap volume (GV) at the tooth-filling interface and the volume of applied composite filling (FV), between the gap and cavity volumes (CV), and between the gap volumes at the tooth-filling interface of the external (EGV) and internal (IGV) parts were calculated. Adhese Universal achieved the significantly lowest gap-to-filling- and gap-to-cavity-volume ratios for both types of etching techniques comparing to those of the Peak Universal and control groups. Significant differences between the gaps in external and internal parts of the tooth-filling interface were only noted in the control groups. Internal gap formation and development at the tooth-filling interface depend on the material as well as the type of its application.

Surface quality evaluation through 3D profilometry of dental restoration performed in a clinical simulated environment

This study evaluated the surface quality of Class V composite resin restorations, comparing the surface roughness resulting from applying three techniques for finishing and polishing in a condition of clinical simulated environment by using artificial dental arcade. Beyond the aesthetic aspect, the importance of the surface quality of the restoration is associated with biofilm accumulation that occur on the teeth restored surface depending on the roughness level, leading to carious lesions and gingivitis. The minimum roughness considered ideal to avoid the accumulation of bacterial biofilm, is 0.2 μm, and 0.5 μm for tactile perception. Most of the evaluations of the surface quality of restorative materials are performed in flat specimens, and the results can significantly differ from the clinical scenario. The present work discloses how heterogeneous the surface quality may result when dealing with natural teeth. The finishing and polishing techniques selected in this work comprised diamond burs and rubber points, diamond burs and surface sealant, and abrasive discs, for restoring premolar natural teeth using a commercial composite resin. The surface quality of the restoration resulting from the three techniques was investigated through Ra, Rt, Rp, R, Rk, Rpk, Rvk and RSm roughness parameters, extracted from 3D topography maps. It was found that the use of abrasive discs (G3) promoted better surface quality, with mean Ra roughness near 0.4 μm, against 0.6 μm for the surface sealant group (G2) and 1.0 μm for the rubber points group (G1). It was evidenced that, together with Ra, analyses of roughness parameters regarding the proportion of peaks and valleys, in this case, Rp and Rpk, and roughness spacing, RSm, were significant to gain confidence and reveal reliable screening of the performance between the three techniques, with the best surface condition of the restored area resulting from the use of abrasive discs.

Delayed vs. immediate placement of restorative materials over Biodentine and RetroMTA: a micro-shear bond strength study

BackgroundThe aim of the present study was to investigate the micro-shear bond strength (µSBS) of various restorative materials applied on two different fast-setting calcium silicate-based materials and to evaluate the effect of restoration time on µSBS.MethodsA total of 180 acrylic blocks with a cavity in the center were randomly divided into 2 main groups according to the capping material to be used (Biodentine or RetroMTA). The specimens were also randomly divided into 3 groups according to the restoration time (3 min, 12 min, 24 h). After the specified waiting periods, glass hybrid material (EQUIA Forte HT), resin composite (Filtek Z550) and light-cured calcium silicate material (Theracal LC) were placed on the specimens with tygon tubes. The specimens were kept for 24 h and then subjected to µSBS test. Statistical analysis was performed by 3-way ANOVA followed by Tukey test for pairwise comparisons (α = 0.05).ResultsThere is a statistically significant difference (p < 0.05) between the µSBS values obtained by applying resin composite on RetroMTA after different setting times (24 h > 12 min > 3 min). The µSBS obtained for the Biodentine-resin composite at the end of the 3 min setting time is significantly lower (p < 0.05) than the µSBS values at 12 min and 24 h. For both calcium silicate cements, at the end of all time periods, the µSBS obtained when resin composite was applied at the end was higher than the other materials (p < 0.05).ConclusionsFor Biodentine-resin composite bonding, the manufacturer’s recommendation of 12 min can be considered an appropriate time, whereas for RetroMTA-resin composite bonding, the µSBS increased as the waiting time increased. Regardless of the waiting time, it is recommended to prefer direct composite resin restoration over Biodentine and RetroMTA.

Comparison of the stress distribution in base materials and thicknesses in composite resin restorations

Resin-based composite materials are commonly used for restorations, but their dimensional changes during the polymerization could cause various clinical problems. This study evaluated the influence of a base of different materials and thicknesses on the stress magnitude and distribution in a second maxillary premolar with an MOD resin composite restoration using three-dimensional finite element analysis. A sound tooth without cavity was considered as the control group (ST), and another group was restored with composite resin without applying a base material in a MOD cavity (CR). The other three groups were restored with composite resin along with the following base materials: glass ionomer cement, low-viscosity resin, and tricalcium silicate, respectively (CR-GIC, CR-LR, and CR-TS). These three groups were further divided into two subgroups according to the thickness of the base layer: thin (0.5 mm) and thick (1.0 mm). The stress distribution was compared using the maximum principal stress after polymerization shrinkage and vertical loading with 600 N on the occlusal surface. Group ST showed the lowest stress value, and its stress propagation was confined to outer enamel surfaces only. Group CR demonstrated the highest stress distribution in the tooth-restoration interface with increased failure risk on marginal areas. The thin and thick subgroups of the three groups with a base layer had lower stress levels than Group CR. The base materials reduced the marginal stress caused by polymerization shrinkage of composite resin in MOD cavities. Different base materials and thicknesses did not affect the stress distribution.

Multidisciplinary Treatment: Follow-Up of Dental Autotransplantation for 10 Years.

The objective is to present a clinical case of dental autotransplantation managed with surgery, orthodontics, endodontics, periodontics, and aesthetic rehabilitation. A 10-year-old boy sought treatment after avulsion of the maxillary left central incisor, which was not reimplanted. Based on anamnesis, clinical examination, and complementary examinations, agenesis of the maxillary and mandibular second premolars except the mandibular right second premolar was observed. After a multidisciplinary planning, the space in the maxillary left central incisor region was opened to receive the transplanted mandibular right second premolar. The receptor site was created in a single surgical procedure. Pulp necrosis was noted in the transplanted tooth, which was treated endodontically, and the agenesis spaces were closed using fixed orthodontic appliances. After removing the appliance, gingivectomy with osteotomy was performed in the maxillary right central incisor and the transplanted tooth regions to harmonize the height and shape of the gingival contour. Next, aesthetic readjustment was performed with tooth whitening, using office and home techniques, followed by microabrasion of the vestibular surface of the maxillary right central incisor. Direct composite resin restorations were placed in the maxillary incisors, and the teeth were rehabilitated using incisal and palatal guides. A multidisciplinary approach is essential for reestablishing the function and aesthetics of complex cases involving dental autotransplantation.

Evaluation of Sealing Ability of New Composite Filling Material

This study was conducted to investigate the sealing ability (microleakage) of new composite restorative materials at tooth/composite interface.Thirty non carious, extracted human premolars teeth were mounted in acrylic resin, the teeth were randomly divided into three groups (n=10) according to the type of composite (tetric T-Econom, Evo ceram,IPS Empress). A standardize class V (5×3×2) mm dimensions cavity was prepared on the facial surface of each tooth (each group with corresponding bur type). After the specimens were filled with three types of composite restoration. They stored for one month in 37ºc distilled water, thermo cycled for 500 cycles between (5ºc &amp; 55ºc) and immersed in 2% methylene blue solution for 24h., and then sectioned longitudinally. For both occlusal and gingival margins, dye penetration at the tooth/composite interfaces were scored from 0-3 under stereomicroscope at a magnification x10. Data were analyzed using unpaired T-test, ANOVA, and Duncan’s multiple rang test at 5% significant level.Kruskal-wallis test show that there was a significant difference in microleakage between the three types of composite it represent that there was less microleakage in group filled with IPS Empress while tetric T-Econom show the highest leakage.There was no significant difference in microleakage between IPS Empress and Evo ceram composite filling.AS Conclusions; Within the limitations of this in vitro study the results show that there was less microleakage in the cavities filled with IPS Empress composite and EVO ceram composite as compared with Tetric T-Econom composite.

Influence of silver fluoride plus potassium iodine on adhesive properties of primary carious dentin-resin interface: An in vitro study

This paper evaluated the influence of different protocols of silver fluoride (SF) pretreatment of artificial carious lesions on the adhesive interface of composite resin restorations and remineralization of deciduous dentin compared to silver diamine fluoride (SDF). Sixty-four deciduous molar teeth were randomly divided into 8 groups (n = 8) according to the restoration time (immediately – IM; 30 days after SDF/SF treatment – 30 D) and treatment before restoration (SDF 38 %; SDF 38 % + potassium iodide – KI; SF 38 %; SF 38 % +KI). After SDF/SF application, teeth in the IM group were restored with self-etch universal adhesive system/composite resin. Samples in the 30D groups were stored in artificial saliva (37 °C) for 30 days before receiving the same restoring protocol. Beams were obtained from all groups and subjected to bond strength tests (µTBS), ultrastructural qualitative analysis (FEG) and mineral analysis (SEM/EDX; Micro-Raman spectroscopy). The µTBS data were subjected to three-factor ANOVA and multiple comparisons (Holm-Sidak method). Bond strength values (MPa) for IM groups were 16.9 ± 2.7 (SDF); 17.6 ± 3.5 (SDF + KI); 16.8 ± 5.5 (SF); 18.4 ± 4.1 (SF + KI); and 14.9 ± 4.2 (SDF); 16.0 ± 5.4 (SDF + KI); 14.1 ± 3.6(SF); 16.4 ± 5.4 (SF + KI) for 30D groups. Bond strength wasn’t influenced by the moment of restoration (IM or 30D); the use of KI didn’t alter adhesion characteristics; SDF/SF solutions resulted in similar adhesive strength; calcium and phosphate expressions were identified at the interfaces on IM and 30D moments. However, 30D presented qualitative increase in these ions, compatible with remineralization. It was concluded that the adhesion of composite resin restorations in artificial caries lesions of deciduous teeth treated with SDF (38 %) and SF (38 %) had similar effects in vitro; the use of KI or the moment when restorations were accomplished did not influence the adhesion and all tested protocols promoted remineralization of carious dentin.

Effect of silver diamine fluoride on the microleakage of flowable resin composite and glass ionomer cement restorations to carious primary dentin: an-in vitro study

BackgroundThis study aimed to evaluate the effect of Silver Diamine Fluoride (SDF) on the microleakage of flowable resin composite (FRC) and resin-modified glass ionomer cement (GIC) restorations bound to carious primary dentin.MethodsForty-four extracted carious primary molars were allocated into four groups as follows (n = 11 teeth/group): Group I, Flowable resin composite (FRCa): SDF38% treatment + FRC, Group II, Flowable resin composite (FRCb): FRC without SDF treatment, Group III, Resin-modified glass ionomer cement (GICa): SDF38% treatment + GIC, Group IV, Resin-modified glass ionomer cement (GICb): GIC without SDF treatment. Specimens were subjected to thermo cycling at 500 cycles between 5 to 55 °C (dwell time of 60 seconds) in baths before being immersed for 24 h in a 1% toluidine blue solution. Microleakage testing was conducted for each specimen in two areas; occlusal and gingival. Specimens were evaluated under stereomicroscope at 4x magnification. Results were analyzed using Kruskal-Wallis test followed by pairwise comparisons utilizing Dunn’s post hoc test at p ≤ 0.05.ResultsInsignificant differences between different groups (p = 0.49) were observed at the gingival walls area readings. The highest value was found in GICb (2.33 ± 0.52), while the lowest value was found in FRCa (1.71 ± 0.76). Insignificant differences between different groups (p = 0.982) were observed at the occlusal walls area readings. The highest value was found in FRCa (1.43 ± 0.98), while the lowest value was found in GICb (1.17 ± 1.33).ConclusionSDF does not adversely affect the microleakage of FRC and GIC restorations bound to carious primary dentin.

Pengaruh perendaman dengan jus umbi bit merah (beta vulgaris l.) terhadap perubahan warna restorasi resin komposit nanofiller

Background: To achieve an aesthetic restoration, it is necessary to choose the right technique and material. Nanofiller composite resin is an option in aesthetic restoration because it has high aesthetic qualities, mechanical properties, and wear resistance. The presence of discoloration in composite resin restorations is undesirable because it interferes with the aesthetic value and appearance. Changes in the color of the restoration caused by extrinsic factors are influenced by color pigments and acidic pH contained in the food and beverages consumed, for example, red beetroot. Objective: This study aims to determine the effect of consumption of red beetroot on the color change of nanofiller composite resin, by immersing it in red beetroot juice. Methods: The object of this research is a cylindrical nanofiller composite resin with a diameter of 10 mm and a thickness of 2 mm. The research was conducted by immersing the nanofiller composite resin in red beetroot juice and aquadest. The study was divided into 2 groups, the control group and the test group, which were placed in an incubator with a temperature of 37oC for 24 hours. In the treatment group, samples were immersed in red beetroot juice for 4 hours for 7 days, followed by immersion in distilled water. In the control group, samples were immersed in distilled water for 24 hours. The color parameters of the research subjects were measured using Vita Easyshade V, before and after treatment for 7 days. After the normality test, the acquired data was statistically tested using Mann-Whitney test and T-test (Independent). Results: The results of this study showed a significant color change (p&lt;0.05). Conclusion: There is an effect of soaking with red beetroot juice on the color change of the nanofiller composite resin.

Attitudes regarding a warranty and the expected longevity of dental treatment amongst New Zealand dentists, dental students, and patients: a mixed methods survey

ObjectivesTo investigate and compare estimates of the longevity of dental treatment, expectations for free remedial treatment, and attitudes about formal dental warranties among dentists, students, and patients.Materials and methodsThis is a mixed-method cross-sectional questionnaire survey with convenience sampling from dentists, dental students, and patients in New Zealand. A questionnaire was distributed to New Zealand dentists (n = 28) and final-year dental students (n = 27). A separate questionnaire was provided to patients in a university dental clinic (n = 43). Mann-Whitney U, Chi-square and Pearson Correlation, and Binary logistic regression tests were used to test for differences between groups and correlations amongst variables. Qualitative data were analysed thematically.ResultsDentists believed that their posterior composite resin restorations would last longer (p = 0.014), would remediate failed crowns for longer (p = 0.002) and would provide longer crown warranties (p = 0.003) compared to students. Patients had higher expectations for restoration longevity and free remediation for failed treatment. Students were generally more willing to provide warranties. Crowns were perceived to be the most warrantable, while endodontic treatment was the least warrantable. Recall attendance, mechanical failure, and adequate oral hygiene were commonly proposed as warranty conditions for restorations and crowns. There was little consensus about complete dentures and endodontic treatment.ConclusionsThere are significant disparities between the expectations of patients and clinicians regarding treatment longevity and free remediation times. Clinicians, in general, are willing to provide free remediation within a specified time frame, except for endodontic treatment, but are hesitant to provide formal dental warranties.

Single crown vs. composite for glass fiber post-retained restorations: An 8-year randomized clinical trial

ObjectivesThis study aimed to compare the success and survival rates of metal-ceramic crowns and composite resin restorations applied in root filled teeth that received a glass fiber post. MethodsA prospective, randomized controlled trial, with equivalent parallel groups was designed. Eighty-two teeth were randomly allocated to the metal-ceramic or composite resin groups. Multivariate Cox regression analysis with shared frailty for patients and Kaplan-Meier curves were performed using success and survival rates (p<0.05). ResultsSeventy-five post-retained restorations (34 metal-ceramic crowns and 41 composite restorations) in 62 patients were analyzed. The median follow-up was 8.1 years [IQR 4.0–9.9]. Twenty-seven failures were observed. Twenty-two failures (81.5 %) were observed in the composite resin group, of which six (27.3 %) were not repairable. Five failures (18.5 %) were observed in the metal-ceramic crown group, of which three (66.6 %) were non-repairable. The cumulative success rate at 8 years was 85.0 % for crowns (AFR=1.31 %) and 43.2 % for composite resins (AFR=6.58 %), while the survival rate was 93.8 % for crowns (AFR=0.52 %) and 97.6 % for composite resins (AFR=0.20 %). Considering the success rates, adjusted multivariate Cox regression showed that composite resin had a Hazard Ratio of 5.07 (95 %CI, 1.99–12.89) greater than the metal-ceramic crown. No significant difference in the failure risk was observed when the survival rates were considered (HR=0.38, 95 %CI (0.10 – 1.44), p = 0.156). Co-variables did not affect the success and survival rates (p>0.05). ConclusionsMetal-ceramic crowns showed a higher success rate than composite restorations. The survival rates were similar, but composite restorations presented a higher need for repairs. Clinical SignificancePost-retained composite restorations may need more reinterventions during the lifecycle, although more preservation of sound tooth structure is expected with a large restoration of resin post-and-core. These aspects have to be discussed with the patient for decision-making planning.

Posterior composite resin restorations combined with stamping technique for increasing vertical dimension: a case report

This clinician's report addressed the crucial consideration of occlusion functionality in aesthetic and oral rehabilitation treatments, highlighting the need to restore the lost vertical dimension. The objective of the study was to evaluate the relevance of recovering the occlusal vertical dimension in aesthetic and rehabilitative treatments, and to determine the viability of composite resin restorations combined with the stamping technique as a restorative option. A comprehensive approach supported by accurate diagnosis and the application of a functional and aesthetic wax-up was proposed. The study focused on the use of posterior composite resin restorations with the stamping technique as a viable restorative alternative. The development and reliability of composite resins and their adhesive systems were highlighted, highlighting their key characteristics. The results obtained demonstrated notable longevity in the restorations, supporting a conservative approach that replicates anatomical details with precision using transparent silicone matrices. Additionally, the benefits of this technique in terms of time and cost efficiency were explored. In summary, this clinical case highlights the importance of implementing an appropriate treatment plan supported by solid clinical evidence. The use of posterior composite resin restorations with the stamping technique to raise the vertical dimension is revealed not only as an effective alternative in aesthetic terms, but also as a long-term sustainable option

Proximal contact tightness of direct Class II composite resin restorations with various matrix systems: A systematic review.

Restoring an ideal proximal contact in direct Class II composite resin restorations is challenging due to polymerization shrinkage, absence of condensability of composite materials, thickness of matrix bands, and the use of various separation techniques, retainers, and bands. The aim of this study was to evaluate the proximal contact tightness that is achieved by various matrix systems used to restore a direct Class II cavity with composite resin restoration. A systematic review was carried out according to the PRISMA 2020 statement guidelines. The online search for the articles was done in electronic databases of MEDLINE/PubMed, Cochrane, and Google Scholar. The articles comparing different matrix systems for restoration were selected. Out of 146 articles, a total of 6 articles met the selection criteria and were included. The QUIN risk-of-bias (RoB) tool was used for assessing the study quality. The data extracted from full text articles selected for inclusion, using a standardized software (Office Excel 2013 Software, Microsoft Corporation, Redmond, WA, USA). Combination of sectional matrices and separation rings resulted in tighter proximal contact compared to other matrix systems.

Comparative Evaluation of Surface Roughness and Colour Stability of Four Different Composite Resins after Application of Desensitising Agents: An In-vitro Study

Introduction: Dentinal Hypersensitivity (DH) is a common clinical condition usually associated with exposed dentinal surfaces. Desensitising agents are regularly used by patients experiencing hypersensitivity, which can affect the physical properties of the existing restorative material. Aim: To evaluate the surface roughness and colour stability of four different types of composite resin restorations after exposure to a desensitising agent. Materials and Methods: The in-vitro study was conducted in the Department of Conservative Dentistry and Endodontics at Ranjeet Deshmukh Dental College and Research Centre, Nagpur, Maharashtra, India from January 2024 to March 2024. Total 56 standardised composite resin discs of size 8×2 mm thickness were prepared using four different types of composites: microhybrid, nanofilled, nanohybrid, and flowable. They were further divided into control and experimental groups based on the application of a desensitising agent, with seven samples in each subgroup. The desensitising agent was applied twice a day for three minutes for one month. Surface roughness was evaluated using a surface profilometer, and colour stability was assessed using a spectrophotometer with the Commision on Ilumination (CIE) L*a*b* formula. The data were analysed using Student’s t-test for pair-wise comparison and One-way Analysis of Variance (ANOVA), with Tukey post-hoc tests for intergroup comparison. Results: The application of a desensitising agent on the samples resulted in a significantly greater effect on the surface roughness of the experimental subgroup than their control counterparts (p≤0.05). Among all groups, the nanofilled group exhibited the lowest surface roughness (0.418±0.047), and the colour change (1.87±0.00) was clinically acceptable. However, the flowable group had the maximum colour change amongst all the other groups (3.16±0.00). Conclusion: Within the limitations of the study, nanofilled composite resin restorative material has minimal surface roughness and colour change after exposure to the desensitising agent. It can be considered the material of choice for restoration in patients with DH.

Esthetic rehabilitation of labial tooth defects caused by caries of the anterior teeth using a composite resin injection technique with veneer-shaped 3D printing indices.

An 18-year-old woman sought treatment for caries of the anterior teeth after completing orthodontic treatment. Direct composite resin restoration was chosen because the patient preferred a minimally invasive and cost-effective treatment whenever possible. Based on diagnostic wax-up, veneer-shaped indices for composite resin injection were designed to replicate and restore tooth defects rapidly and accurately. The overall esthetic result was excellent after a 1-year of follow-up. Direct freehand composite resin restorations are clinically challenging. The recently proposed 3D printing index for the composite resin injection technique is helpful for direct restoration but is challenging to remove. The veneer-shaped indices avoid the formation of an undercut in the direction of removing the index, making them easy to remove after finishing the restorations. Using veneer-shaped indices for composite resin injection enables rapid esthetic rehabilitation of labial tooth defects caused by caries. This approach reduces chairside time and operational difficulty while allowing for easy index removal after completing the restorations.

Comparison of Reverse Sandwich Restorations Versus Composite Fillings for the Restoration of External Cervical Resorptions: An In-Vitro Study.

The aim was to compare the 'reverse sandwich restoration' to resin composite restorations re- garding marginal adaptation, fracture resistance, favourable/unfavourable fractures in the management of external cervical resorption. Forty-eight extracted maxillary central incisors were selected and endodontically treated. Cervical regions of the labial root surfaces received simulated resorptive defects and were restored as three randomly allocated groups: Reverse Sandwich Restoration (resin composite + resin-modified glass ionomer) (RSR); resin composite restoration (COMP), and no restoration (NR). Each group was further divided into two subgroups (n=8 each): Thermomechanical Aging (TA) (equivalent to one year) and No Aging (NA). Marginal adaptation was scored by scanning electron microscopy. Fracture resistance was tested using a universal testing machine. Favourable versus unfavourable fractures were classified based on fracture extent. TA decreased the marginal adaptation for both RSR and COMP. Mean fracture resistance per groups were: RSR-NA 1522.4+-94.9N, RSR-TA 939.6+-72.9N, COMP-NA 1197.6+-95.7N, COMP-TA 870.4+-86.3N, NR-NA 1057.1+-88.1N, and NR-TA 836.6+-81.9N, respectively. Fracture resistance was the highest for RSR- NA compared to all other groups (p<0.05). TA decreased the fracture resistance in all groups (p<0.05), there was no significant difference between RSR and COMP regarding fracture resistance and favourable/ unfavourable fractures (p>0.05). RSR provided comparable results to resin composite fillings to restore artificial cervical defects pertaining to marginal adaptation, fracture resistance, and favourable versus unfavourable fractures. RSR is preferable due to its inherent biocompatibility to the periodontium. (EEJ-2023-04-050).

Clinical Longevity of Sonicated and Unsonicated Composite Resin Restorations in Posterior Permanent Teeth: A Systematic Review and Meta-Analysis

Clinical Longevity of Sonicated and Unsonicated Composite Resin Restorations in Posterior Permanent Teeth: A Systematic Review and Meta-Analysis