Anchorage System Research Articles

A Study on the Impact of Temperature on the Anchoring Durability of Carbon-Fiber-Reinforced Polymer Cables

To improve the application of carbon-fiber-reinforced polymers (CFRPs) in civil engineering, the long-term durability of CFRP anchorage systems has become a critical issue. Temperature fluctuations can significantly impact the bond performance between CFRPs and the load transfer medium (LTM), making it essential to understand the effects of temperature on the durability of CFRP anchorages. Therefore, this study investigates the influence of temperature on the durability of CFRP anchorages through aging tests on 30 epoxy-filled CFRP-bonded anchorage specimens, followed by pull-out tests. The long-term degradation of CFRP cable anchorage performances in representative regions of the globe was predicted using Arrhenius theory. The experimental results show that after long-term temperature exposure, the maximum bond strength of the CFRP-LTM interface in the anchoring zone degrades after 30 days but continues to increase after 150 days. In contrast, the residual bond strength of the CFRP-LTM interface in the anchorage zone continuously decreases over time, with the degradation rates gradually decreasing over time. Higher temperatures lead to more severe degradation of anchoring performance. Based on the experimental results, it is predicted that the anchoring performance of a CFRP cable anchorage system will reach degradation rates of 63.72%, 83.36%, and 94.73% after 50 years in regions with average annual temperatures of 0 °C, 10 °C, and 20 °C, respectively. Therefore, the temperature has a significant long-term impact on the anchoring performance of CFRP cable bonding systems, necessitating a more conservative design in higher-temperature areas.

Study on the application of thermal-meltable recovery of CFRP strand anchors

Conventional pressure-type anchoring systems face challenges such as difficulty in recovery, low recovery efficiency, and insufficient durability over long-term use. Although the single-use cost of Carbon Fibre Reinforced Polymer (CFRP) strand anchors is higher than that of conventional steel strands, recovery and reuse can significantly reduce costs. Therefore, this study aims to investigate the bonded anchoring method of CFRP and proposes an innovative thermoplastic CFRP prestressed strand design that combines both anchoring strength and recoverability to address the shortcomings of existing anchoring systems. Two bonding materials, thermosetting resin and thermoplastic resin, were selected for bond strength tests under different conditions. The results indicated that epoxy resin had a bonding force of 280 kN and an anchoring efficiency of approximately 70%, making it the most suitable material. However, the anchoring efficiency still needs improvement. Based on this, an improved design scheme was proposed, which can increase anchoring efficiency to over 95%. Additionally, based on the dispersed bonding anchor system, this study explored a solution that involves adding a positioning plate at the end of the anchor strand and using epoxy resin for anchoring. The anchoring performance tests showed that the tensile strength of the CFRP strand ranged from 2.7–2.8 GPa, with an average anchoring efficiency of 100.5%, demonstrating excellent anchoring performance. Further thermoplastic recovery tests showed that when the temperature increased to 90°C, the maximum recovery force of the strand was 17.2 kN, about 4.4% of the ultimate load. When the temperature increased to 150°C, the maximum recovery force was 7.5 kN. The recovered CFRP strands were clean, with no resin residue, and had no damage, maintaining an intact structure. The proposed thermoplastic CFRP prestressed strand design demonstrates significant advantages in anchoring strength and recoverability. With the improved design, anchoring efficiency can be increased to over 95%, and the high-temperature recovery process shows good feasibility. Compared with traditional anchoring systems, CFRP strands offer higher anchoring efficiency, lower recovery force requirements, better economics, and sustainability, making them a promising solution for engineering applications.

Transcatheter Left Ventricular Reconstruction in HeartFailure Patients With Prior Anterior Myocardial Infarction: The Prospective ALIVE Trial.

Left ventricular (LV) dilatation and extensive scar portend a poor prognosis in heart failure (HF). The Revivent TC system (BioVentrix Inc) is used either during a hybrid transcatheter-surgical or a surgical-only procedure to exclude transmural scar and reduce LV dimensions. The purpose of this study was to examine the safety and efficacy of the Revivent TC® anchor system in patients with HF. We conducted a prospective, multicenter, nonrandomized (2:1 device vs control) trial in patients with NYHA functional class III-IV symptoms, LV ejection fraction≤45%, LV end-systolic volume index≥50mL/m2, and transmural anterior LV scar. Patients with inadequate scar or previous sternotomy served as the control group. The primary safety endpoint was the composite of major adverse events in the device arm compared with a performance goal of 40.5%. The primary effectiveness endpoint was the hierarchical composite of cardiovascular mortality, HF hospitalization, change in 6-minute walk test, change in Minnesota Living With HeartFailure questionnaire score, and change in NYHA functional classification assessed at 12months as the win ratio in the device group compared with the control group. In total, 126 patients (84 device; 42 control) were enrolled at 28 sites. Mean LV ejection fraction was 29.6%±7.2%, and mean LV end-systolic volume index was 93.9 ± 35.5mm. The primary 30-day safety performance goal endpoint was met (major adverse events 15 of 84 [17.9%]; 1-sided 97.5% upper confidence limit 27.7%; P<0.0001). There was no significant difference in the primary 12-month hierarchical composite efficacy endpoint (win ratio 1.13; P = 0.32). In post hoc analysis, the surgical only approach (23 treated patients) had more favorable outcomes than the hybrid approach (60 treated patients). The Revivent TC® system safely reduced LV dimensions in HF patients caused by extensive anterior scar but did not improve clinical effectiveness outcomes at 1 year. A randomized trial is warranted to further define the risks and benefits of the surgical only approach. (BioVentrix Revivent TC™ System Clinical Study; NCT02931240).

Effectiveness of Treating Vertical Maxillary Excess Among Non-growing Adult Patients With Skeletal Anchorage System: A Systematic Review and Meta-Analysis of Case Reports From 2008 to 2023

Effectiveness of Treating Vertical Maxillary Excess Among Non-growing Adult Patients With Skeletal Anchorage System: A Systematic Review and Meta-Analysis of Case Reports From 2008 to 2023

Reuse of CFRP Pultrusions in Novel Post-Tensioning Cables for Bridge Strengthening

This paper presents the development and validation of a new filament-wound CFRP sleeve and resin grout for the efficient anchorage of parallel CFRP wire bundles. Twenty-five-year-old, reused CFRP wires (recovered from two dismantled bridge cables) were examined with regard to any possible drop in strength or stiffness due to aging and then processed into two bridge strengthening cables. The new anchorage and cables were tested to their tensile capacity (giving on average 1.833 MN) in two full-scale instrumented experiments. This being successful, it gave the authors the confidence to manufacture two new 26–30 m long post-tensioning parallel-wire cables, each using 37 of the recovered CFRP wires. Both CFRP parallel-wire cables were finally successfully prestressed to 1 MN (55% of their UTS) in order to strengthen an existing bridge in the Swiss Alps over the river Ilfis in the summer of 2023. This strengthening project is described. The full-scale tests confirmed the durability and strength of the new anchorage system, and the feasibility for reusing valuable CFRP pultrusions for post-tensioning was proven by the successful bridge strengthening carried out. Finally, the project also demonstrated the sustainability potential of CFRP pultrusions. The monitoring data of this bridge project are presented and discussed.

A Pool of Bacterium-like Particles Displaying African Swine Fever Virus Antigens Induces Both Humoral and Cellular Immune Responses in Pigs

Background/Objectives: African swine fever (ASF), caused by African swine fever virus (ASFV), poses a significant threat to the global swine industry. This underscores the urgent need for safe and effective ASF vaccines. Methods: Here, we constructed five bacterium-like particles (BLPs) that each display one of the five ASFV antigens (F317L, H171R, D117L, B602L, and p54) based on the Gram-positive enhancer matrix-protein anchor (GEM-PA) system. GEM is a bacterial particle that contains only peptidoglycan, while PA is composed of three lysin motifs (Lysm) derived from the C-terminus of the AcmA protein, capable of non-covalently binding to GEM. By fusing the ASFV antigens with PA, the ASFV antigens can be firmly attached to the surface of GEM. Subsequently, the piglets were immunized via intramuscular injection with a mixture of BLPs-F317L, BLPs-H171R, BLPs-D117L, BLPs-B602L, and BLPs-p54. Results: The results showed that the piglets developed detectable serum IgG antibodies 2 weeks after the first immunization, and these high antibody levels were maintained 4 weeks after the booster immunization. Moreover, these piglets produced more IFN-γ-producing lymphocytes than the control piglets. Conclusions: The data indicate that the generated BLPs mixture can stimulate both humoral and cellular immune responses in piglets, these five ASFV proteins are promising antigens, and the BLPs generated represent candidate ASF vaccines.

Numerical Simulation of Anchor Pullout and Shear Tests Using a Regularized Damage Model

The prediction of the mechanical behavior of anchorage plates in reinforced concrete is crucial for ensuring equipment reliability, particularly in sensitive installations. This paper employs finite element analysis to forecast the experimental outcomes of anchor pullout and shear tests. In this article, a regularized damage model is proposed to simulate the effects of loads transmitted to the concrete by the anchor rod. Specifically, a modified Mazars model is introduced, incorporating an “energetic” regularization in both tension and compression. The model is validated for a single anchor rod under tension and subsequently for a complete anchorage system subjected to both tension and shear forces. Various failure modes, such as concrete cone cracking or steel rupture, are accurately represented, alongside the overall anchorage strength. This approach, thus, faithfully reproduces the mechanical behavior of anchorage plates, ensuring equipment robustness under diverse loading conditions.

Use of bore-epoxy anchorage system with CFRP laminates for shear strengthening of RC beams: An experimental and analytical investigation

Shear strengthening of reinforced concrete (RC) beams with externally bonded reinforcement (EBR) using carbon fiber reinforced polymer (CFRP) plates and sheets have become a widely accepted practice. To avoid the associated premature debonding failure, this study presents an experimental and analytical investigation on the use of bore-epoxy as an anchorage system for CFRP plates and sheets bonded on both sides of shear deficient RC beams of rectangular cross-sections. Nine (9) RC beams were prepared and strengthened with CFRP plates and sheets as EBR with bore-epoxy anchorage system considering different bore diameters and tested under four point bending. The results indicate that RC beams strengthened with bore-epoxy anchorage system have high shear strength as compared with the unstrengthened control beam and those strenghtended with the conventional EBR approach (without boring). The increase in the shear strength over the control beam was found to be up to 67 % and 121 % for cases of CFRP plates and sheets, respectively. Moreover, the increase of shear strength in comparison with the conventional EBR method ranged from 9.33 % to 20.36 % for CFRP plates and from 12.97 % to 36.10 % for CFRP sheets. Consistently, the contribution of bore-epoxy on the shear strength increased with the increase of bore diameter. Consequently, the existing formulas in the ACI440.2 R for predicting the shear strength of FRP strengthened RC beams were modified to incorporate the improvement made by the proposed bore-epoxy approach. The revised models predicted the experimental shear strength of RC beams, strengthened with bore-epoxy, with a good level of accuracy with average mean absolute percentage error (MAPE) = 6.07 %, 14.71 %, normalized mean square error (NMSE) = 0.097, 0.16, and coefficient of determination R2 = 0.912, 0.974 for plates and sheets, respectively.

Research on the Dynamic Response of a Bedding Rock Slope Reinforced by Pile–Anchor Structures Under Earthquakes: A Case Study of a Section of the Duyun-Shangri-La Expressway Project in Ludian County, Yunnan Province, China

Pile and anchor structures are extensively employed for slope stabilization. However, their dynamic response under seismic loading remains unclear and current seismic designs primarily use the pseudo-static method. Here, a three-dimensional numerical simulation of the dynamic behavior of a bedding rock slope supported by pile–anchor systems under earthquakes is conducted. The dynamic calculation for the slope subjected to seismic forces with varying excitation directions and acceleration amplitudes is performed. The dynamic behavior of both the slope and the pile–anchor system is investigated with respect to the slope’s failure mode, the dynamic soil pressure behind the pile, the anchor axial force, the bending moment, and the lateral displacement of the pile. The results indicate that the anti-slide piles cause a reflective and superposition effect on seismic waves within weak rock layers. As the input seismic intensity increases, the axial force in the anchor cables also increases, with the peak axial force occurring during the main energy phase of the seismic waves. The dynamic soil pressure acting behind the piles varies with the stratification of the slope rock layers, with lower peak dynamic earth pressure observed in weak layers. The weak layers on the slope surface experience through-shear failure. Under strong seismic loading, the structural element state undergoes significant changes.

Experimentally optimized anchored-FRP method: A high-strength, cost-effective and ease-to-install technique for concrete rehabilitation

Conventional EB-and NSM-FRP techniques tend to prematurely fail in FRP delamination, suggesting inefficient utilization of the FRP materials. Various anchorage systems have been developed by integrating FRP anchors with FRP patches or groove bond to maximize the utilization of FRP materials. This study proposes a simpler but robust method that can make full use of FRP materials while minimizing the need for groove excavation, FRP patches, epoxy adhesive and surface preparations. The reinforcement was achieved by externally bonding FRP reinforcement to the concrete surface, with bent anchors being embedded into the strengthened elements. 51 experiments were conducted to demonstrate the potentials of the proposed method, which successfully prevented premature debonding failure, thereby offering robust rehabilitation solutions with a reduction of up to 42 % in epoxy usage compared to current methodologies. The results also suggested the impact of key parameters, such as cross-sectional area, embedment depth, and multi-reinforcement arrangement, on the effectiveness of the proposed FRP technique. Based on the experimental findings, discussions and recommendations were presented to facilitate the continued advancement of the proposed FRP methodology, aiming to fully develop FRP strength and minimize the need for FRP materials and epoxy adhesive in comparison to the current anchored FRP methods.

Experimental study on seismic performance of glulam structural columns with anchored connections

In current timber structures, the low initial stiffness, and weak bending resistance of the connections result in significant structural deformation and failures. To improve the mechanical capabilities of timber structural joints, a novel timber-component anchorage system with robust bending resistance was introduced. Thirteen scaled-down specimens of glulam columns with anchored connections were meticulously fabricated for testing, scaled at a ratio of 1/2. Cyclic loading tests were conducted, considering three types of the volume compression percentage of confined wood perpendicular to the grain; and five axial-load levels. Subsequently, various seismic performance aspects of glulam columns with anchored connections were examined, including the failure mode, hysteresis behavior, envelope curve, strength degradation, stiffness degradation, energy dissipation capacity, and critical points. During the analysis, the influence of the P–Δ effect on the results was discussed and a damage-based hysteretic model was presented. Finally, a comparison of the mechanical performance for various types of timber structural joints was conducted. The findings revealed that the failure mode of the anchored glulam columns occurred as cracking perpendicular to the grain, and the anchored columns exhibited superior bending resistance and overall seismic performance.

Deep learning-based automated identification on vortex-induced vibration of long suspenders for the suspension bridge

Large amplitude vortex-induced vibration (VIV) of long suspenders, caused by vortex-shedding and wake flow, will decrease the service life of high-strength wires and its anchorage systems, hence listed as an essential monitoring indicator of the structural health monitoring system in the suspension bridges. Traditionally, a static vibration amplitude limitation is usually predefined and used to identify VIV from continuously monitored acceleration data of bridge suspenders. Due to the complexity of the starting vibration of the suspenders, it may not be able to flexibly adapt to the suspenders VIV under different conditions. In addition, transient but significant vibration events may not be captured since it relies only on static vibration amplitude limits without considering the temporal information of vibration. To address the above-mentioned issues, a novel framework to autonomously identify the suspenders VIV is proposed using the multimodal fusion techniques with deep neural networks. The main contributions of the methodology are: i) by calculating the wind field and vibration characteristic, two vibration response parameters are identified as indexes for the identification of suspenders VIV based on the significant difference method of big data analysis; ii) Two different modal information of time history images and power spectral density (PSD) sequences are used as inputs to the convolutional neural network (CNN) and bidirectional long short-term memory (BiLSTM) to extract the suspenders vibration response features from the time and frequency domain perspectives, respectively; and iii) The multimodal information is concentrated and enhanced by the multi-head attention (MHA) mechanism to achieve automated identification of the suspenders VIV. The proposed framework is validated with data collected from a full-scale long-span suspension bridge in comparison with the base model. The results show that the proposed framework can efficiently identify the full-cycle development process of the suspenders VIV. This study provides a convenient strategy for suspenders VIV identification, which can be used for bridge management and vibration mitigation device design.

Cellular Automata-Based Experimental Study on the Evolution of Corrosion Damage in Bridge Cable Steel Wire

Cable-stayed bridges have become the preferred bridge type for large-span bridges due to their unique advantages, and the long-term performance of the cable under the extreme conditions has been facing great challenges. An accelerated corrosion test was carried out using in-service cable, and the evolution model of the etch pit was established based on cellular automata to study the evolution law of corrosion damage to steel wire. This study showed that with the increase in the number of dry-wet cycles in the electrified accelerated corrosion, the macro- and micromorphology of the steel wire showed more serious corrosion damage, the tensile strength decreased, the ductility index decreased, and the tensile strength of the steel wire after corrosion decreased by nearly 5%; the geometric dimension of the steel wire etch pits all met a right-skewed distribution with a broader range of etch pit depth, mainly consisting of shallow spherical etch pits and deep ellipsoidal etch pits. The length, width, and depth sizes were mainly distributed in the range of 0.005 mm to 0.015 mm, 0.005 mm to 0.02 mm, and 0 mm to 0.04 mm; at the early stage of corrosion, the etch pits were first developed along the longitudinal direction. As the corrosion process progressed, the iron matrix participated in the electrochemical reaction, leading to the rapid expansion of the etch pits’ dimensions. The stress concentration effect at the bottom of the etch pit caused the maximum stress to approach 1800 MPa, with a stress concentration coefficient of more than 3.0; when the cable anchorage system was located in the connecting sleeve and the threaded splice seam, where corrosion protection was prone to failure, the outer steel wire bore most of the corrosive effects, and the internal cable was less eroded by the corrosive medium.

An innovative strategy for improving ductility of seawater sea-sand engineered cementitious composites beam reinforced with GFRP bar

Seawater sea-sand engineered cementitious composites (SS-ECC) members with glass fiber reinforced polymer (GFRP) bars have inferior ductility due to the brittle nature of GFRP bars. In the current research, an enlarged head anchorage system (EHAS) was recommended to improve the ductility of GFRP bars reinforced SS-ECC beams. To explore the bond characteristics between SS-ECC and GFRP bars with EHAS, a total of 39 specimens were tested by pull-out loading. The influences of enlarged head shape, stirrup spacing and SS-ECC's strength grade on the bond characteristics were experimentally investigated. GFRP longitudinal bars in specimens with EHAS presented rupture failure rather than anchorage failure. EHAS could effectively realize the slip hardening of GFRP bars in low strength SS-ECC, and ensure the reliable bond of GFRP bars in high strength SS-ECC. Additionally, the failure mechanism of specimens under pull-out loading was explored by finite element analysis (FEA). The pull-out resistance was mainly provided by EHAS in force transition stage and slip hardening stage. The influences of fiber reinforced polymer (FRP) bar type on the bond performance were investigated by FEA. EHAS could realize the slip-hardening behaviors of aramid, basalt and carbon FRP bars in normal strength SS-ECC. More importantly, to verify the effectiveness of the proposed ductility enhancement strategy, SS-ECC beams reinforced with GFRP bars were tested by four-point bending. These beams with different enlarged head shapes possessed excellent ductility and strong ultimate deformation capacity. It was recommended that low strength SS-ECC and GFRP bars with EHAS were jointly utilized to enhance the ductile performance of the beams.

Development of an anchor system for thick CFRP plates: Experimental and numerical investigation

Carbon fiber reinforced polymer (CFRP) has been widely used in construction, rehabilitation and maintenance of civil infrastructures. Anchor system is one of the most crucial part ensuring load transfer between CFRP and the structures. However, for CFRP plate anchors, there is a contradiction between the anchor capacity and the anchor size. In this paper, a novel cylinder shaped anchor for thick CFRP plates was developed based on a detailed experimental and numerical study. The proposed anchor weighs only 6 kg and it can develop 98 % strength of the 3 mm thickness CFRP plates. The experimental and numerical results revealed that the anchor efficiency of the proposed cylinder shaped anchor system is significantly affected by wedge shape, anchor material, tooth shape, pretightening force and magnitude of interference. The proposed anchor system can significantly promote application of thick CFRP plates.

TCT-461 Development of A Novel Multi-Point Adjustable Anchoring System for Percutaneous Left Ventriculoplasty

TCT-461 Development of A Novel Multi-Point Adjustable Anchoring System for Percutaneous Left Ventriculoplasty

A Spring Model for Pullout Behavior of Curved, Flexible Structures Embedded in Soil

ABSTRACTThe shape and flexibility of embedded structures, such as tree roots, piles, and anchors, have important impacts on the pullout behavior. However, the rate and manner of mobilization of soil resistances along such structures has not been rigorously explored across a wide range of shapes and structural properties. A spring model for computing compatible displacements of the structure and soil for curved, flexible structures is defined, validated against commonly used methods for computing pile pullout behavior, and then parametrically explored to demonstrate how resistances are mobilized along the length of such structures. The present model allows description of combined axial and transverse loading of these nonlinear structures. The simulation results for the case of normally consolidated clay show that the curvature of a structure causes the distribution of bearing resistance to extend further along the structure than for linear cases. The requirement of equilibrium of the structure produces a coupling between the mobilized bearing and tensile resistance in terms of rate of development and magnitude. Thus, the choices of structure shape impact the magnitude and distribution of mobilized resistance of embedded flexible structures. Implications for anchorage of tree root structures and principles of bioinspired design of anchorage systems are discussed.

Динамическая модель харвестера, оснащенного канатной анкерной системой, при проведении лесозаготовительных работ на крутом склоне

The efficiency of using logging machines for work in mountainous or hilly areas characterized by the presence of steep slopes depends on many factors, among which the quantitative parameters of the dynamic state of both the harvester itself and the anchor system play a priority role to ensure the safe operation of these technological machines. This article considers a complex spatial dynamic model that combines into a common interconnected system all the main components of the simulated phenomenon, including directly a harvester with a hydraulic manipulator mounted on it, a movable assortment in space, an anchor system consist-ing of an anchor rope and a winch, an anchor tree for attaching an anchor rope and the soil of the support surface. The dynamic mathematical model of such a six-component system includes 35 generalized coordinates that determine the linear and angular displacements of the mass centers of the listed system components. A system of 35 differential equations constructed using the Lagrange’s equation was solved by the 4-th-order Runge-Kutta method. For this purpose, a computer program has been developed, the description of which is contained in the article. In relation to the basic version of the simulated system with quantitative initial characteristics focused on the characteristics of a three-axle wheeled harvester with a 6K6 wheel formula, calculations of oscillatory processes for dynamic parameters determining the loading of the anchor system and the safety of harvester operation in the process of assortment manipulation were carried out.

Acoustic Emission (AE) based health monitoring of RC beams strengthened with mechanically anchored hybrid Fiber Reinforced Cementitious Matrix (FRCM) system

The debonding between fabric and matrix/substrate hampers the strength and durability of fiber-reinforced cementitious matrix (FRCM) strengthened elements. One of the ways to improve the performance is to use mechanical anchorages. However, damage mechanisms associated with such systems are complex, and structural health monitoring of such systems is quite challenging. While earlier studies have concentrated on monitoring the health of FRCM coupons using acoustic emission techniques, they did not account for the effect of impregnation or use of mechanical anchorages. Also, very few studies are available on the health monitoring of full-scale FRCM-strengthened specimens. The current investigation employs AE-based health monitoring to classify the damage characteristics of reinforced concrete (RC) beams strengthened with FRCM. Two strengthening strategies, with and without mechanical anchorages, are employed. The non-anchored system involves conventional strengthening using two layers of pre-impregnated fabric, while the mechanically anchored method utilizes pre-impregnated fabric and a distributed anchorage system. The AE data is then analyzed using several parameters correlated with the digital image correlation (DIC) technique. Trends of sentry function, historical index, and cumulative signal strength (CSS) provide insights into major event occurrences and changes in the underlying damage modes. Three different b-values indicate a transition from micro to macro cracks during different loading stages. On the other hand, frequency content and RA-AF analysis are employed as qualitative tools to identify the source and type of damage. The strengthened RC beams with mechanical anchorages exhibited a 20.9 % increase in flexural capacity compared to those without, as evidenced by the AE parameters and DIC techniques. Overall, the study revealed that acoustic emission health monitoring could effectively evaluate the overall condition of the strengthened system, even with the complexity of a multi-part composite system.

Beyond the screw: Exploring the recurrence of oral lesions

The integration of skeletal anchorage systems has revolutionized orthodontics, especially with the advent of mini-screws known for their ease of use and minimal invasiveness. The mandibular buccal shelf area, with its ample high-quality bone and low failure rates, has become a preferred extra-alveolar anchorage site. However, complications involving adjacent soft tissues are common with orthodontic bone screw placement. This case report describes the recurrence of reactive oral lesions following placement of orthodontic bone screws in the buccal shelf area. During the course of orthodontic therapy, the patient developed exophytic growths twice, at the same site, on the lower right back buccal mucosa. Diode laser was used in both instances for excision of the lesion and the specimen was sent for histo-pathological analysis. The first lesion was diagnosed as inflammatory fibrous hyperplasia, while the recurrent lesion was identified as pyogenic granuloma. At 12-months follow-up, no new lesions were detected. This report highlights the influence of lesion development time on its clinical and histological presentation. It is postulated that leaving the bone screw in place after initial biopsy could have contributed to its recurrence. Complete excision is the preferred treatment. Treatment options, including laser therapy, are available for such lesions.