Composite Placement Research Articles

Temperature change of the pulpal floor and restoration with preheated bis-GMA free and containing resin composite (a randomized clinical trial)

BackgroundPreheating is one of several innovative approaches and improvements developed to increase the durability and clinical behavior of resin composites. Development of preheated composites is to reduce its viscosity in order to improve resin composite adaptation and placement ease. The purpose of this clinical trial was to study the effect of preheating Bis-GMA free and Bis-GMA-containing resin composites at different temperatures on the pulpal floor and restoration temperature. A total of twenty individuals (N = 40) have two carious posterior teeth that need to be restored were randomly assigned to one of two groups based on the type of restorative materials used: (group 1) Bis-GMA-containing resin composite VisCalor bulk (VCB), and (group 2) Bis-GMA-free resin composite Admira Fusion x-tra (AFX). Preheating temperatures of 50 °C and 70 °C were utilized to separate each group into two subgroups. Class I or II cavities were prepared. Thermometer device with two separate K-type temperature probes was used to measure the base line temperature values at the pulpal floor before beginning the restorative procedure (C0), pulpal floor during packing of preheated composite (C1), the top composite surface after packing and before curing (C2), pulpal floor after curing of the preheated composite (C3), and top composite surface after curing (C4). One-way ANOVA and the Kruskal–Wallis test were used to analyze the data.ResultsThe measured temperature of pulpal floor for both preheated VCB or AFX at 50 °C or 70 °C revealed significant increasing from base line measured temperature to during packing as well as after curing with (P-value < 0.001). There was no significant difference for mean composite surface temperature for both preheated materials at 50 °C or 70 °C whether before or after curing.ConclusionsPreheating of bulk fill Bis-GMA free and containing resin composite rises both the pulpal floor and the restoration temperature; meanwhile, the rise in temperature was limited. The application of the curing unit caused the greatest temperature rise.

Multidisciplinary management of orthodontic patients at the University of Port Harcourt Teaching Hospital, Rivers State, Nigeria

Background: Orthodontic patients may present with complex dentofacial problems that require treatment by more than one dental specialist as well as medical specialists. Such patients present not only with malocclusion but also dental caries, periodontal diseases, dental trauma, missing teeth, sleep apnoea among others. Multi-disciplinary management allows for effective and efficient comprehensive care. The aim of this study was to highlight the multidisciplinary care of orthodontic patients at University of Port Harcourt Teaching Hospital. Materials and Methods: A 7-year retrospective study of patients who attended the Orthodontic Clinic in the Department of Child Dental Health, University of Port Harcourt Teaching Hospital, Port Harcourt, Nigeria. Data collected from the patients’ files was analysed using IBM Statistical Package for Social Sciences (SPSS) Statistics for Windows version 25.0. Results: A total of 200 patients with an age range of 4-44years comprising 80 (40%) males and 120 (60%) females were included in the study. The majority of patients, 145 (72.5%) had scaling and polishing performed by paediatric dentists whilst 53 (26.5%) adult patients were seen by a periodontologist. Eight (4%) had root canal therapy, composite and glass ionomer cement (GIC) restorations placement by a restorative dentist whilst 6 (3%) had teeth replaced by the prosthodontist. The patients were also co-managed by oral and maxillofacial surgeons (28,14%), Ear Nose and Throat surgeons (3,1.5%), paediatricians (5, 2.5%) and neurosurgeons (2, 1%). Conclusion: Multidisciplinary management of our patients was by both medical and dental specialists particularly paediatric dentists and periodontists.

Two-stage model of prepreg bonding interface formation in automated fiber placement process

While Automated Fiber Placement (AFP) of thermoset matrix composites are widely used in the aviation industry, there is little conclusive research on the relationship between the physical model of bonding interface formation process and the actual bonding strength between prepreg layers formed in AFP process. Although massive amounts of experimental data on prepreg tack have been achieved from existing research, engineers are unable to use these data as a decisive criterion in choosing process parameters. In this research, a prepreg layup physical model based on reptation model and viscoelastic mechanical model is built, in which the bonding interface formation process is divided into two stages, namely, diffusion and viscous stage. Layup-peeling experiments are conducted via a special designed high-speed layup experimental platform so that practical AFP process parameters can be imitated, and a logarithmic curve of layup velocity-peeling energy under different layup pressure is achieved. The slope of the logarithmic curve and the surface morphology of the sample after peeling prove the correctness of the established model. Simultaneously, the experimental data proves that when prepreg is peeled off, the transition from the cohesive failure mode to the interface failure mode occurs at the laying speed between 100 mm/s and 200 mm/s. These results can be used as a reference for choosing AFP process parameters to realize the balance between good bonding quality and harmless separation of adjacent prepreg layers.

Comparative Evaluation of Microleakage in Premolars after Placement of Microhybrid and Nanohybrid Composite Using Snow Plow Technique

Background: Microleakage is the significant reason for composite restoration failure. The type of composite material utilized should reduce polymerization shrinkage and hence avoid micro-leakage.&#x0D; Objectives:&#x0D; &#x0D; To evaluate microleakage in Class I cavity using microhybrid composite in snow plow placement technique.&#x0D; To evaluate microleakage in Class I cavity using nanohybrid composite in snow plow placement technique&#x0D; To compare microleakage in Class I cavity with microhybrid composite and nanohybrid composite using snow plow placement technique.&#x0D; &#x0D; Methodology: Prepared Class I cavities in 22 human premolars will be divided randomly into 2 groups based on the restorative material used. These cavity preparations will be restored using the snow plow technique. All the specimens will be thermocycled and stained with 50% silver nitrate solution. We will wash the specimens in the distilled water, store them in the developing solution and for 24 hours exposed to sunlight. The samples will be sectioned longitudinally from the middle of cavity into two parts and will be then evaluated for microleakage on the basis of silver nitrate penetration under stereomicroscope (20X). To compare the microleakage, data will be subjected to statistical analysis.&#x0D; Expected Results: Nanohybrid composite placement using snow plow technique is expected to have less micro-leakage than microhybrid composite placement using the same technique.&#x0D; Conclusion: If this study proves correct, this would be helpful for the clinicians to choose the most efficient restorative material with the best technique and minimal microleakage which will aid in the success of the root canal treatment.

Pain Perception Associated with Mini-Implants and Interventions for Pain Management: A Cross-Sectional Questionnaire-Based Survey.

Background Orthodontists use mini-implants temporarily as an effective mode of skeletal anchorage devices. The placement of mini-implants can cause pain and discomfort to the patients. Patients often develop swelling, and the pain could interfere with their daily activities. Practitioners tend to prescribe antibiotics and pain medication for management. Objectives The main objectives of this study are to evaluate the pain perception and discomfort due to mini-implant placement experienced by the patient and evaluate the interventions for pain management commonly practiced among orthodontists. Materials and Methods The study was designed as a questionnaire-based cross-sectional study. A total of 271 patients were assessed, for whom 625 mini-implants (ranging from 1.2 to 2 mm diameter and length 8-14 mm) were placed. Pain scores were assessed using the VAS and the “Faces” pain rating scale to collect data about discomfort in daily activity and function. Data was collected from 244 patients. A total of 155 orthodontists were questioned regarding the prescription of medications and the interventions for managing pain and adverse effects. Results Average pain score among female subjects was 16.71 and among men was 13.5. The highest pain scores were recorded for palatal mini-implants with an average score of 36.29 and the least for interradicular mini-implants with an average score of 9.02. Among the subjects, 47.9% of them took analgesics, and the most commonly prescribed analgesics were paracetamol (39%). Swelling at the site is where the mini-implants were placed, and ulceration due to implants were commonly dealt with the excision of the surrounding soft tissue, composite placement, and palliative care with oral analgesic gels. Conclusion Female subjects had more mini-implants placed, and female subjects had also given more pain scores than their male counterparts. Palatal mini-implants caused the highest pain, followed by mini-implants placed at the infrazygomatic crest and the buccal shelf region. Palatal mini-implants caused maximum discomfort during speech and eating, followed by the mini-implant in the buccal shelf and the infrazygomatic crest region that also caused difficulty in yawning and laughing. Infiltration anesthesia was commonly given for the placement of interradicular implants and extra-alveolar mini-implants. Paracetamol was the most prescribed by the orthodontists, and more than half the doctors did not regularly prescribe antibiotics.

Placement of composites in the masticatory load-bearing posterior region (in German)

Direct composite restorations are placed in the cavities in the posterior region using an incremental layering technique. Numerous different layering concepts are described in the literature. However, only those procedures that can be easily and reliably applied in routine clinical treatment have become established in daily practice. This article is intended to provide a clinically oriented overview of the most common layering procedures for the direct restoration of posterior defects with plastic composite materials.

Composite versus Amalgam Restorations Placed in Canadian Dental Schools.

To investigate the latest teaching policies of posterior composite placement versus amalgam and to determine the actual numbers of posterior composites versus amalgam restorations placed in Canadian dental schools, over the years from 2008 to 2018. Emails were sent to Chairs/Heads of Restorative Departments and Clinic Directors of all 10 Canadian dental schools to collect data in the forms of: 1) Questionnaire on current teaching policies of posterior composite and amalgam restorations; 2) data entry form to collect the actual numbers of posterior composite and amalgam restorations placed in their clinics. For the teaching questionnaire, the response rate was 90% (n=9). Seven (78%) of the responding schools reported that they assign 25%-50% of their preclinical restorative teaching time towards posterior composite placement. While, three (33%) of the responding schools allocated 50%-75% of their restorative teaching towards amalgam placement. Data entry response rate was 80% (n=8). Amalgam material was dominant in the restoration distribution from 2008 to 2012. While from 2013 to 2018, resin composite material was dominant in all eight responding schools. Linear regression analysis revealed a significant increasing trend in placing posterior composites in all the responding schools over time (p<0.05). Data analysis revealed a clear trend towards an increase of posterior composite restoration placement and a decrease in the number of amalgam restorations placed. However, the teaching time assigned for posterior composite is not aligned with quantity placed. Review and adjustment of time allocated for teaching and training of each material are recommended.

The effect of composite placement technique on the internal adaptation, gap formation and microshear bond strength.

This study aimed to compare the efficiency of placement technique on internal adaptation, gap formation and microshear bond strength (SBS) of bulk-fill composite resin materials. Standardized class V cavities were prepared for microcomputed tomography (mCT) test and divided into four groups (n=12) as follows: Group SDR: Smart Dentin Replacement system/bulk fill; Group SF2: Sonic-Fill system/bulk fill sonic-activated composite placement system; Group CHU: Herculite-XRV-Ultra composite resin inserted with Compothixo/sonic-vibrated composite resin placement system; Group HIT: Herculite-XRV-Ultra composite resin applied with incremental technique. Self-etch adhesive (Optibond-XTR) was used for bonding in all groups. After 10000 thermocycling, mCT scans were taken to reveal gap formation at the toothrestoration interface and universal testing machine was used to test microshear bond strength SBS values (n=10). ANOVA, post-hoc Bonferroni and Tukey HSD tests were used for evaluating the gap formation and SBS values p=0.05. SF2 and CHU showed the best adaptability compared with both SDR and HIT. The difference between groups SDR and HIT was statistically significant (p<0.05).SBS values were found to be the highest for SF2, and the lowest for HIT groups (p>0.05). Bulk-fill composite resins placed either with sonic-activated or sonic-vibrated instrument demonstrated better adaptability, less gap formation and higher bond strength than both the bulk-fill flowable composite and conventional incremental techniques.

Relocation and reinforcement of the adhesive/composite interface with spontaneous amine-peroxide interfacial polymerization

ObjectivesThis study demonstrates a spontaneous redox polymerization process located at the adhesive-composite interface that precedes photocure of the composite with the intent to improve bonding. MethodsAn aromatic amine and benzoyl peroxide redox initiator system was partitioned between BAPO-photoinitiated BisGMA/HEMA adhesive and BisGMA/TEGDMA resin-composites. The composite was placed on the photocured adhesive layer with a brief delay before photopolymerization of the composite layer. Micro-tensile bond strength between the adhesive and composite was assessed in comparison with the non-redox active control materials. ResultsThe presence of amine or peroxide in these resins without the redox initiation contribution enhanced both the rate and the final conversion of the BAPO-based photopolymerizations. Control formulations using redox-only initiation showed active polymer formation starting at approximately 30 s when physical mixing of the redox components was involved; however, simply by waiting 60 s between composite placement and photocure provided adequate time for passive interfacial diffusion of benzoyl peroxide from the pre-cured adhesive into the overlaid aromatic amine-containing composite such that a sufficient degree of redox initiated interfacial polymerization occurred prior to the composite photocure. The result was a significant increase in the adhesive to composite micro-tensile bond strength with the failure site moved away from the mainly interfacial failure noted for the control. SignificanceThe stress-free autonomous pre-conversion of a redox-initiated thin film of composite that then provides a compositionally homogeneous interface for composite photopolymerization offers a means to enhance at least short-term bond strength between the adhesive and composite phases during restorative placement.

Current and future trends in the teaching of direct posterior resin composites in Malaysian dental schools: a cross-sectional study

ObjectiveTo investigate the current and future teaching of posterior composite restorations in undergraduate curricula in Malaysian dental schools. MethodsA 24-item validated questionnaire including closed and open questions on the teaching of posterior composites was emailed to faculty members in all 13 Dental Schools in Malaysia. Responses were compiled on Excel and analysed. ResultsAll 13 dental schools responded to the survey yielding a 100 % response. All schools indicated the use of posterior composites for 2- and 3-surface cavities in premolars and molars. The didactic teaching time devoted to composites was greater than for amalgam (38 h vs 29 h). Clinically, most posterior restorations placed by students were composites (average 74.1 %, range 10 %–100 %); the remaining 25.9 % were amalgams (range, 0 %–50 %). Slot-type cavities were the preparation techniques most commonly taught (n = 11,84.6 %). The use of rubber dam for moisture control was mandatory in most schools (n = 11, 84.6 %). History of adverse reaction to composites was found to be the most common contraindication to composite placement. The phase down of teaching and use of amalgam in Malaysia is expected to occur within the next six years. ConclusionThe trend to increase the teaching of posterior composites reported for other countries is confirmed by the findings from Malaysian dental schools. Notwithstanding this trend, the use of amalgam is still taught, and future studies are required to investigate the implications of the phase down of amalgam in favour of posterior composites. Clinical significanceNotwithstanding the increase in the teaching of posterior composites there is a pressing need to update and refine clinical guidelines for the teaching of posterior composites globally.

Heat transfer modelling of flashlamp heating for automated tape placement of thermoplastic composites

Flashlamp systems introduce pulsed and broadband heating to automated tape placement (ATP) offering greater control and optimisation potential. A thorough understanding of the role of operation parameters on the process is necessary to unlock these capabilities. A 2D finite element model of the heat conduction, able to analyse the temperature field evolution in the time scales of short high-energy pulses, was developed and combined with ray tracing analysis in this work. The model was validated against experimental data from ATP trials of AS4/PEEK composites. Parametric studies showed that pulse duration and frequency influence significantly both the surface and bulk temperature profiles. Longer pulses lead to higher irradiation temperatures, whilst the profiles converge to the behaviour of a continuous source of equivalent power at high frequency. The versatility of flashlamp heating enhances the processing envelope through expanding the feasible combinations of maximum temperature and depth of penetration achievable in ATP processing.

Comparative Evaluation of Depth of Cure between Two Bulk-fill Composites and a Conventional Resin Composite: An In Vitro Study

ABSTRACT Aim and objective To evaluate and compare the depth of cure of two bulk-fill composites with a conventional composite. Materials and methods A sample size of 36 was taken and divided into three groups based on the type of composite. Standardized cylindrical stainless steel molds were prepared with 8 mm diameter and 10 mm depth. Measurement of depth of cure by the scraping method was performed according to the ISO 4049 (2009). After placing the specimens, the mold was pressed with polyester strips covered by glass slides and curing was initiated using Bluephase 20i (Ivoclar Vivadent US) light-curing unit through the glass slide. Immediately after curing, the specimens were removed from the mold and the uncured part of the specimens was removed by scraping with a plastic spatula. The absolute length of the hardened composite specimen was measured using a digital vernier caliper. The measured length was divided by two and recorded as the ISO depth of cure. Results The depth of cure of the composite specimens was found to be higher for Voco Xtra Fil bulk-fill composite than for Shofu Beautifil bulk-fill composite and Filtek Z350 XT conventional composite (3M/ESPE). Conclusion Within the limitations of the study, it can be concluded that the placement of bulk-fill composites with 3-mm increments is mandatory for complete curing. Clinical significance Depth of cure of bulk-fill composites determines the adaptation of restoration to the tooth structure, and this study aims to evaluate two newly introduced bulk-fill composites using scrape test. How to cite this article Bastian M, Vineet RV, Mathew J, et al. Comparative Evaluation of Depth of Cure between Two Bulk-fill Composites and a Conventional Resin Composite: An In Vitro Study. Cons Dent Endod J 2020;5(2):23–27.

Effect of two desensitizing agents on post-operative hypersensitivity of composite resin restorations

Post-operative hypersensitivity still occurs although the improvements in adhesive systems and their techniques, so the current study was conducted to evaluate the efficacy of two desensitizing systems. Materials and methods: A total No. of 48 patients were randomly divided into 3 groups (n=16); Gluma group, SAD group, and control group. Class I cavity preparation and self-etch bonding technique was used by Universal bonding system in the control group, before that desensitizing agent was applied in the two desensitizing tested groups, light cured and composite placement incrementally (Tetric N-ceram) and light cured, finishing, and polishing of composite restorations, then VAS system was used to record post-operative hypersensitivity by patients, and after 1 day,1 week and 1 month the data collected and statistically analyzed. Results: Total number of patients who suffered from post-operative hypersensitivity was 15 patients (31.25 %) after one day of treatment, the total number decreased to 9 patients (18.75 %) after one week postoperatively, and after one month the total number decreased again to 4 patients (8.33 %). In all the tested groups 1 day gave a significant difference than one week ( P= 0.011*),,,

Thermal analysis of cylindrical molds using thermoplastic composite during robotic fiber placement

Thermoplastic composites have gradually become a hotspot due to its low manufacturing cost and good weld ability. In this study, to realize the placement of the thermoplastic composite material carbon fiber/polyether ether ketone (CF/PEEK), the consolidation roller of the existing thermoplastic composite placement head is optimized. The process simulation analysis of the thermoplastic composite material is carried out. A two-dimensional heat transfer model of the thermoplastic prepreg laying process is established in ANSYS. Transient thermal analysis is carried out using the life and death unit technology. The optimum machining parameters are obtained through analyzing the influence of mold temperature, laying speed, and heating temperature on the temperature field of the first layer in curved surface laying.

Composite veneers: The direct-indirect technique revisited.

This article provides an update on the direct-indirect composite veneer technique. Composite veneers have long been used as a conservative and esthetic treatment option for anterior teeth. While they are generally performed using a direct technique, there has been renewed interest in the direct-indirect composite veneer technique because of its advantages and broad indications for restoration of tooth color and morphology. In the direct-indirect composite veneer technique, the selected composites are initially applied on the tooth using a layering approach, without any bonding agent, sculpted to a primary anatomic form with slight excess, and light-cured. The partially polymerized veneer is then removed from the tooth, heat-tempered, and finished to final anatomy and processed extra-orally before being luted. Advantages of this technique include enhanced physical and mechanical properties afforded by the tempering process, unrivaled marginal adaptation, enhanced finishing and polishing, and the ability to try-in the veneer before luting, enabling a shade verification and modulation process that is not possible with the direct technique. The direct-indirect approach also affords enhanced gingival health and patient comfort. This article reviews the direct-indirect composite veneer technique, and outlines critical steps and tips for clinical success. The direct-indirect technique for composite veneers combines advantages of the direct composite placement technique with those of the indirect veneer technique, including operator control, single-visit fabrication and delivery, increased material properties, and excellent esthetics.

Amalgam Phase-Down Part 2: UK-Based Knowledge, Opinions, and Confidence in the Alternatives

Introduction:Amalgam use has recently been phased down, and the potential for a phase-out is being investigated.Objectives:The study aimed to identify knowledge of the phase-down and opinions of a potential phase-out of amalgam by UK primary care clinicians and assess their confidence in using different materials in different situations.Methods:An anonymized, prepiloted cross-sectional e-survey was used to assess primary care clinicians’ knowledge and opinions of the amalgam phase-down and potential phase-out and their confidence in using amalgam and the alternatives in different situations. In total, 11,902 invitations were distributed through British dentist and therapist associations. Prior hypotheses were tested alongside descriptive statistics.Results:Response rate was 13% (n = 1,513). Knowledge of the amalgam phase-down was low, with just 3% clinicians correctly identifying all patient groups in whom amalgam use should be avoided in the United Kingdom. Postgraduate education on posterior composite placement was high (88%), but a large majority had personal and patient-centered concerns over the suitability of the alternatives and lacked confidence when placing composite in comparison to amalgam in difficult situations (P < 0.0001). Logistic regressions revealed that the best predictors of high confidence in placing mesio-occluso-distal composites and composites in difficult situations were being a private general dentist or being primarily a composite user.Conclusion:Primary care clinicians have major personal and patient-centered concerns regarding the amalgam phase-down (of which they have limited knowledge) and potential phase-out. Many lack confidence in using the alternative, composite, to restore posterior teeth in difficult situations, whereas confidence in using amalgam in similar situations is high. Effective education of clinicians and understanding patients’ needs, alongside policy changes, are required to enable a successful amalgam phase-down and potential phase-out.Knowledge Transfer Statement:This study shows that UK primary care clinicians are worried about the phase-down of amalgam for themselves and their patients. Many lack confidence in the alternative, composite, when used in difficult situations, which is in stark contrast to amalgam. Knowledge of the phase-down is limited. There is a need for more effective education of clinicians, an understanding of patients’ values, and policy changes to ensure the success of the phase-down and potential phase-out of amalgam.

Placement of posterior composite restorations in United Kingdom dental practices: techniques, problems, and attitudes

To investigate the range of techniques used by U.K. general dental practitioners when placing posterior composites, their attitudes and opinions and problems encountered. A pre-piloted questionnaire was distributed to 500 UK GDPs selected at random from the U.K. Dentists Register requesting specific information on attitudes, use and problems encountered in relation to posterior composite placement. 254 useable replies were returned (response rate= 51%). Over 95% of respondents would consider placing posterior composites, but only 33% (n=84) would regularly or often place composite in the occlusal surface of a molar tooth. 62% of respondents (n=157) are influenced by articles in peer-reviewed journals when deciding to place a posterior composite, while 95% (n=241) reported that they are not influenced by advertising. Techniques for managing operatively exposed dentine vary, and are related to the depth of the dentine cavity: 79% (n=201) use a 'dentine-bonding' technique (i.e., no base/liner) approach for shallow cavities, while only 9% (n=23) would consider this approach for a deep dentine cavity. Only 10% of respondents (n=25) use a sectional metal matrix system for restoring occlusoproximal cavities, while 29% (n=74) use transparent matrix systems, and 61% (n=155) use a circumferential metal matrix system. More than one-half (52%, n=132) of practitioners reported they experienced problems with food packing in more than one in four posterior composites placed. Despite having been previously discouraged by financial guidelines and with probable limited exposure to posterior composite instruction at dental school, U.K. GDPs are placing posterior composites with reasonable reference to current best available evidence. Diverse opinions exist on the management of certain clinical scenarios, such as of operatively exposed dentine.

Clinical Performance of Direct Anterior Composite Restorations Using Esthetic Dual-Shade versus Polychromatic Natural Layering Technique: a split mouth randomized controlled clinical trial

Objective: to evaluate the clinical performance of the dual shade layering and polychromatic resin composite layering techniques using a randomized controlled trail. Material and Methods: 42 participants (84 restorations) of class IV or class III through and through within a pair of anterior contra-lateral teeth were randomly allocated into two groups according to technique of composite restoration placement: control “polychromatic layering” and intervention “dual-shade layering”. Follow-up was done at 1 month (baseline) and 1 year. Restorations were evaluated using Visual Analog Scale (VAS), restoration color shade match using Vita Easyshade V ®, and blinded assessor using FDI criteria for assessment of dental restorations measuring (aesthetic properties). Chi-square test was used to compare between restorations of both techniques. Results: There was no statistically significant difference between restorations of both techniques for patient satisfaction outcome, restorations color match outcome, and for all tested FDI outcomes except surface luster with 100% success. Conclusion: Both dual-shade layering and polychromatic natural layering techniques, exhibited acceptable clinical and esthetic performance. Keywords Composite; Polychromatic layering technique; Dual-shade layering technique; Clinical performance.

Real-time monitoring of thermal history of thermoplastic automatic lamination with FBG sensors and process modelling validation

Automated fibre placement (AFP) of thermoplastic composites has been reaching a high efficient and technological level in the last years. In situ consolidation (ISC) process involves cost reduction since extra autoclave cycle is not required. A good control of the temperature and pressure during the lamination is mandatory to achieve a good consolidation without thermal degradation for the manufacturing of high quality parts. Due to the manufacturing set-up, temperature monitoring is limited to infrared thermographic cameras and superficial measurements. Within this context, Fibre Bragg grating (FBG) sensors emerged as a potential device for thermal history monitoring in real-time. An investigation was carried out by using different FBG sensors for process monitoring of thermoplastic ISC. In this study, the sensors were embedded inside CF/PEEK thermoplastic samples and the lamination process was subsequently monitored. Also, a thermal model was created in order to obtain a simulated thermal history of the process. The process was successfully monitored, and it has been demonstrated that FBG sensors are a useful tool for thermoplastic ISC process monitoring. The results provided by the sensors allowed to identify different phases of the process (heating, consolidation and cooling down). The thermal history of the process was monitored by encapsulated FBG sensors acting as temperature probes. A good correlation between the sensors and the thermal was found. In addition to that, First steps were taken for strain history monitoring by means of FBG sensors.

Laparoscopic Repair of Primary and Secondary Epigastric Hernias. Technical Considerations of the IntraPeritoneal On Lay Mesh + Defect Closure (IPOM-Plus Technique)

We present our experiences with the laparoscopic repair of primary and secondary (incisional) epigastric hernias that occur in the vicinity of bony structures. In our institute, we retrospectively reviewed 51 patients with primary and secondary epigastric hernias from 2002 to 2016. The European Hernia Society guidelines were used for classifying these hernias. Laparoscopic dissection of the falciform ligament, intracorporeal suturing of the defect and intraperitoneal composite mesh onlay placement was performed in all patients. There were 32 males and 19 females with a mean age of 40 years and a mean BMI of 29.5kg/m2. There were multiple defects in eight patients (15.68%). The mean hernial defect size was 5.75 cm2 (range 3–8.5 cm2). The surface of the used mesh was ranging from 225–400 cm2 (mean 312.5 cm2). Mean follow-up was nine months. Morbidity rate was 11.7% and the recurrence rate was 1.9%. Upper abdominal hernias are difficult to manage laparoscopically because of the complexity of dissection and their anatomic proximity to the falciform ligament, xiphoid and costal margins. Multiple defects and associated hernias can also be easily identified and laparoscopically repaired simultaneously with the placement of a large mesh. The mesh borders can be adequately fixed beyond the bony confines via the laparoscopic approach, which would otherwise be impossible in the open technique. Laparoscopic repair of these hernias is safe and effective and provides all the benefits of minimally invasive surgery.