Dentists' Perspective and Experiences Relative to the Accidental Dropping of Implant Drivers and Components Intraorally: A Survey of Practicing Clinicians.

Ingestion or aspiration of dental implant screwdrivers or implant components is potentially life-threatening. There are no reports on the frequency at which dentists drop these devices within the mouth or which components are most problematic. There are few reports on what protective measures clinicians take, where risks exist, and how this problem is managed. A 9-part questionnaire was provided to dentists. Data collected included clinicians' roles, implant surgeons, restorative clinicians, or both-the frequency of dropping implant screwdrivers or components, items considered most problematic. Patient protection and management were also requested. Finally, questions related to how much of a problem clinicians considered this to be and if further solutions and a standardized management protocol should be developed. One hundred twelve dentists voluntarily completed the survey. Of the dentists, 54% restored, 37% restored and surgically placed, and 9% solely placed implants. Twenty-nine percent claimed never to drop components, with 56% dropping an instrument less than 10% of the time. Less than half would suggest patients seek medical advice if a screwdriver or component was accidentally dropped intraorally and was not recovered. Thirty percent never tied floss tethers to screwdrivers, and a similar percentage reported they only sometimes did so. Throat pack protection was reported 51% of the time. Ninety percent considered dropping components an issue, with screwdrivers most problematic. Aspiration or ingestion of implant screwdrivers and components is problematic, with dentists varying their use of protection devices. There is a need to standardize and implement patient protection procedures and management and develop methods to reduce the risk of these potentially life-threatening issues.

Determining the manner of death in victims in drug-induced psychosis: a case of an atypical head stab wound.

This case report presents a rare case of an atypical head stab wound suffered by a drug addict and inflicted with a screwdriver during drug-induced psychosis. It describes the diagnostic and treatment procedures in the hospital and the findings of the subsequent autopsy. It also analyzes the review of the interpretation of the CT scans made upon admission and the subsequent treatment by an independent medical review panel, which revealed signs of medical mismanagement. Therefore, it also discusses the legal consequences that the case may have involved for the attending physicians in addition to the consequences for the suspected perpetrator. The report raises many issues encountered in the case in terms of the clinical treatment and forensic determination of the manner of death in cases of injuries caused by sharp instruments and highlights the importance of comprehensive evaluation of the circumstantial evidence together with the clinical or autopsy findings, since such evidence may sometimes be overlooked in clinical practice.

Modified individualized titanium mesh in orbital floor reconstruction for preventing exposure.

Objective: To describe a novel method of medial fixation of titanium mesh with a right-angled screwdriver for orbital floor and maxillary reconstruction and to compare the reconstruction outcome of orbital floor reconstruction with modified and traditional methods. Methods: The data of 23 patients who underwent maxillectomy and orbital floor defect reconstruction by individualized titanium mesh in Peking University School and Hospital of Stomatology between 2018 and 2021 were retrospectively reviewed. While eight patients received modified orbital floor reconstruction with titanium mesh and angled screwdriver (group A), 15 patients received traditional orbital floor reconstruction (group B). The contact area with buccal flap for titanium mesh in groups A and B was calculated. Titanium mesh deformation, fracture or exposure was recorded. Postoperative ophthalmic function and success of esthetic restoration were assessed. Results: Mean follow-up was for 15.7 months (range, 9-22 months). The contact area with buccal flap for the modified titanium mesh in group A (13.11 ± 1.41 cm2) was significantly less than that of the traditional titanium mesh in group B (21.83 ± 1.23 cm2; p < .05). The exposure of titanium mesh occurred in two patients in group B. The self-evaluation of facial symmetry for 23 patients showed no significant difference between group A (7.75 ± 0.71) and group B (6.68 ± 1.30; p > .05). No specific complications were reported. Conclusion: We propose a novel method of zygomatic medial fixation of titanium mesh with a right-angled screwdriver for orbital floor and maxillary reconstruction, which has the potential to prevent the postoperative exposure of titanium mesh. Level of Evidence: Level III (Retrospective comparative study).

Biomechanical Investigation of Bone Screw Head Design for Extracting Stripped Screw Heads: Integration of Mechanical Tests and Finite Element Analyses.

Enhancing the design of bone screw head sockets to prevent stripping and improve the torque required for smooth unscrewing is a significant challenge in orthopedic applications. This research aims to establish a quantitative methodology by integrating mechanical testing with finite element (FE) simulations to determine a safe limitation depth for the screwdriver when engaging with the hexagonal socket, thus avoiding stripped screw heads. A FE model was developed to investigate the biomechanical responses of the screw head design. Five custom-made hexagonal sockets were manufactured, and single load torsional tests were conducted to assess the mechanical performance of the screws and drivers. The results from the mechanical tests were compared with the FE simulations, demonstrating a close agreement and confirming the model's validity. Furthermore, additional FE models were created to study the impact of manufacturing tolerances on the socket width and screwdriver width. The findings revealed that the maximum torque to failure for the four designs was lower than the margins specified in ISO 6475. Additionally, increasing the depth of the screwdriver led to higher maximum torque values. This research suggests that the technique of screw insertion, specifically the depth of the driver tool within the screw socket, holds greater importance in preventing stripped screw heads than the design and manufacturing width of the bone screw's hexagonal socket and screwdriver. This confirms the importance of screwdriver engagement inside the bone screw socket to prevent stripped screw heads and sheds light on the added value of maximum torque prediction for future design modifications.

Piercing the surface: A mechanical analysis of stabbing with household tools.

Estimating the applied power during a stabbing incident, or estimating the minimal force necessary to penetrate the body with a certain weapon is a challenging task in forensic practice. A thorough forensic evaluation of stabbing forces needs objective numerical experimental data. Stabbing tests of 12 different weapons - including knives, a pair of scissors, a fork, screwdrivers, a rasp, a corkscrew, and a utility knife blade - were performed with a Mecmesin MultiTest-dV material tester on pork loin and ballistic gel to estimate the stabbing forces and dynamics. Penetration force (Fp ) and maximal force (Fmax ) were recorded, and the registered force curves were analyzed. Fmax was 159.8-212.07 Newton (N), 30.56-30.58 N, 168.9-185.48 N for various knives; 171.39-190.43 N for the pair of scissors, 233.6 N for the fork; 532.65-562.65 N, 370.31-367.19 N and 314.51-432.89 N for various screwdrivers, 44.14-56.62 N for utility knife during pork loin stabbing. The butter knife, corkscrew and rasp were not able to penetrate the pork loin, and the curved fork bent during stabbing. The results prove that weapon characteristics greatly influence the force necessary for penetration. Maximal stabbing force depends mostly on tip sharpness, and the force sharply decreases after penetration occurs, which indicates that edge sharpness is not as important as tip characteristics during stabbing perpendicular to skin surface. The penetration force during stabbing with a pair of scissors is comparable to the penetration force of knives. Stabbing with screwdrivers generally needs larger force than average knives but depends greatly on screwdriver size.

Nance-Horan Syndrome: characterization of dental, clinical and molecular features in three new families.

BACKGROUND: Nance-Horan syndrome (NHS; MIM 302,350) is an extremely rare X-linked dominant disease characterized by ocular and dental anomalies, intellectual disability, and facial dysmorphic features. CASE PRESENTATION: We report on five affected males and three carrier females from three unrelated NHS families. In Family 1, index (P1) showing bilateral cataracts, iris heterochromia, microcornea, mild intellectual disability, and dental findings including Hutchinson incisors, supernumerary teeth, bud-shaped molars received clinical diagnosis of NHS and targeted NHS gene sequencing revealed a novel pathogenic variant, c.2416 C > T; p.(Gln806*). In Family 2, index (P2) presenting with global developmental delay, microphthalmia, cataracts, and ventricular septal defect underwent SNP array testing and a novel deletion encompassing 22 genes including the NHS gene was detected. In Family 3, two half-brothers (P3 and P4) and maternal uncle (P5) had congenital cataracts and mild to moderate intellectual deficiency. P3 also had autistic and psychobehavioral features. Dental findings included notched incisors, bud-shaped permanent molars, and supernumerary molars. Duo-WES analysis on half-brothers showed a hemizygous novel deletion, c.1867delC; p.(Gln623ArgfsTer26). CONCLUSIONS: Dental professionals can be the first-line specialists involved in the diagnosis of NHS due to its distinct dental findings. Our findings broaden the spectrum of genetic etiopathogenesis associated with NHS and aim to raise awareness among dental professionals.

Helping Surgeons' Hands: A Biomechanical Evaluation of Ergonomic Instruments.

PURPOSE: "Ergonomic" is a common descriptor for a desk or computer workspace but is a term rarely used to describe a surgical instrument. Instead, surgeons spend many hours in inconvenient positions, often using instruments that are not ergonomic. Improving the ergonomics of surgical instruments may decrease the required force for simple tasks and allow for more efficient surgery. METHODS: To evaluate the impact of ergonomic surgical instruments, the authors developed ergonomic screwdriver handles. The shape and size of these handles were engineered using previous dental studies and 3-dimensional modeling to create an ideal handle for specific glove sizes. Participants were recruited to test 3 different ergonomic handle sizes against a standard screwdriver while assessing digital peak force, digital contact area, and participant preference. Ten participants (3 women) with glove sizes ranging from 6 to 8 were evaluated. RESULTS: Ergonomic screwdriver handles sized for glove sizes 6 and 7 required significantly less thumb peak force than the standard screwdriver for all participants (702 N for glove size 6 and 567 N for glove size 7 ergonomic screwdrivers, vs 1780 N for "one size fits all" standard screwdriver). Participants consistently preferred screwdrivers that required lower thumb and index finger forces. All ergonomic handles required lower thumb and index finger force. Eighty percent of participants preferred a screwdriver modeled within 1 glove size of their own. CONCLUSIONS: Improved ergonomic handles require less force and are preferred by surgeons. CLINICAL RELEVANCE: The significant decrease in thumb peak force for glove sizes 6 and 7 suggests that there is room for ergonomic improvement in instruments, especially for surgeons with smaller hands. Manufacturing ergonomic screwdriver handles and using the evolving convenience of 3-dimensional printing may help to develop a more comfortable work environment for surgeons.

Brown-Sequard syndrome associated with a spinal cord injury caused by a retained screwdriver: A case report and literature review.

Background: Nonmissile penetrating spine injury (NMPSI) represents a small percent of spinal cord injuries (SCIs), estimated at 0.8% in Western countries. Regarding the causes, an NMPSI injury caused by a screwdriver is rare. This study reports a case of a retained double-headed screwdriver in a 37-year-old man who sustained a stab injury to the back of the neck, leaving the patient with a C4 Brown-Sequard syndrome (BSS). We discuss the intricacies of the surgical management of such cases with a literature review. Methods: PubMed database was searched by the following combined formula of medical subjects headings, (MESH) terms, and keywords: (((SCIs [MeSH Terms]) OR (nmpsi [Other Term]) OR (nonmissile penetrating spinal injury [Other Term]) OR (nonmissile penetrating spinal injury [Other Term])) AND (BSS [MeSH Terms])) OR (BSS [MeSH Terms]). Results: A total of 338 results were found; 258 were case reports. After excluding nonrelated cases, 16 cases were found of BSS induced by spinal cord injury by a retained object. The male-to-female ratio in these cases is 11:5, and ages ranged from 11 to 72. The causes of spinal cord injury included screwdrivers in three cases, knives in five cases, and glass in three cases. The extracted data were analyzed. Conclusion: Screwdriver stabs causing cervical SCIs are extremely rare. This is the first case from Iraq where the assault device is retained in situ at the time of presentation. Such cases should be managed immediately to carefully withdraw the object under direct vision and prevent further neurological deterioration.

Patterned injuries from screwdrivers.

A 40-year-old man was stabbed multiple times with a cross-tipped, Phillips head screwdriver with many of the puncture wounds characterized by a cruciate pattern consistently measuring approximately 5 × 5 mm corresponding to the shape of the weapon. Death was due to a single penetrating wound to the chest that had transfixed the aorta. This report characterizes the features of injuries that may be inflicted by Phillips head screwdrivers, contrasting this with injuries that may occur if the weapon is a flat or slotted head screwdriver. Given their ready availability, ease of handling, and sharpness, screwdrivers are surprisingly rarely used in fatal assaults.

Percutaneous reduction with double screwdrivers versus limited open reduction in the treatment of irreducible extracapsular hip fractures.

BACKGROUND: The reduction in irreducible extracapsular hip fractures has always been controversial. Here, we present a new minimally invasive reduction technique and compare it with limited open reduction (LOR) to treat irreducible extracapsular hip fractures. METHODS: From January 2016 to January 2018, our institution treated 653 patients with extracapsular hip fractures by intramedullary fixation. Among them, 525 cases got a successful closed reduction. The other 128 were irreducible and reduced by percutaneous reduction with double screwdrivers (PRDS) or LOR. There were 66 cases in the PRDS group while 62 in the LOR group. All fractures were classified using the Evans-Jensen classification. In addition, the differences in incision length, blood loss, fluoroscopic number, operation time, inpatient time, weight training time, Harris score, and complications were analyzed. RESULTS: The incision length was 8.4 ± 1.4 cm in the PRDS group and 15.3 ± 3.0 cm in the LOR group, respectively (p < 0.05); blood loss was equal to 151 ± 26 and 319 ± 33 ml, respectively (p < 0.05); fluoroscopic number was 14 ± 3 and 8 ± 2, respectively (p < 0.05); operation time was 44 ± 9 and 73 ± 11 min, respectively (p < 0.05); inpatient time was 6.2 ± 1.7 and 8.4 ± 2.2 days, respectively (p < 0.05); weight training time after the operation was 4.5 ± 1.5 and 10.7 ± 1.8 days, respectively (p < 0.05); and the excellent rate of Harris score was 92.4% and 88.7%, respectively (p > 0.05). There was no significant difference in complication incidence between the two groups (p > 0.05). CONCLUSIONS: The PRDS group presented better clinical effects for managing irreducible extracapsular hip fractures than the LOR. Therefore, the PRDS technique could be the first reduction choice for patients with irreducible fractures.

The contact length parameter as a geometric factor for user-centered design of pistol grip geometries of power tools.

In this study the geometric parameter of the contact length is introduced, which intends to combine force exertion and perceived handle comfort in an anthropometric length in order to determine an optimal handle circumference. To prove suitability of the approach, 31 subjects were determined and correlations to handle circumferences with the highest finger forces and highest rated comfort were investigated. For all fingers, medium correlations were found among the contact lengths and the circumferences determined with maximum force (p < 0.001, rindex = 0.348, rmiddle = 0.419, rring = 0.374 and rlittle = 0.337) with high accordance of median values. Weak to moderate correlations were found between circumferences with maximum comfort and the contact lengths (p < 0.001, rindex = 0.150, rmiddle = 0.265, rring = 0.174). Using finger-specific proportionality factors, the contact lengths can be determined directly from the hand lengths, which enables great benefits for user-centered design.

Screwdriver aspiration during implant surgery: case report and literature review / 口腔疾病防治

Objective @#To discuss and summarize the preventive measures and treatment methods for aspiration/ingestion during dental procedures.@*Methods @# One case of aspiration during an implant operation was reported, and the literature on aspiration/ingestion during oral procedures was reviewed.@*Results@#An implant screwdriver accidentally slipped into the mouth of the patient during implant surgery. The patient experienced no obvious discomfort except a few coughs. The surgeon and assistant paused the procedure immediately to search for the screwdriver, but it was not found. The patient declared that there was no special abnormality, such as breathing disorder or chest distress, so we considered that the foreign body was ingestion. After the implant surgery was completed, no foreign body was found in the stomach via gastroscopy. Chest X-ray and CT showed a dense metal shadow in the lower lobe of the left lung. Under local anesthesia, bronchoscopy and biopsy forceps were used by respiratory physicians to clip out the foreign body. After removal of the foreign body, the patient had no obvious discomfort but a slight cough. Cephalexin and metronidazole were given for three days to prevent infection. Three days later, the patient had no complaints of respiratory discomfort. After reviewing the literature, we found that the operation should be paused immediately after aspiration/ingestion occurs during dental procedures and that the dental chair should be laid down to prevent the foreign body from descending deeper, which may increase the difficulty of removal and cause gastrointestinal and respiratory tract injury. The position of the foreign body should be determined by imaging examination, and the corresponding means to remove the foreign body should be performed.@*Conclusion @# Patients may have no obvious symptoms after aspiration/ingestion during dental procedures, and the foreign body can be removed after imaging examination.

[Development and clinical application of universal screwdriver].

OBJECTIVE: To develop a universal screwdriver for sealing the end of the central hole of the femoral interlocking intramedullary nail, so as to shorten the operation time of the tail cap implantation of the intramedullary nail and improve the accuracy of implantation. METHODS: Total 77 patients with intertrochanteric fractures underwent femoral interlocking intramedullary nail (FIIN) surgery from June 2018 to June 2019. There were 28 males and 49 females, aged 55 to 80 (76.22± 7.32) years old, and course of disease was 20 to 40 h. All patients were divided into universal screwdriver group (39 cases) and ordinary screwdriver group (38 cases) according to whether the self-developed universal screw was applicable during the operation. The blood loss during tail cap implantation, the time of tail cap implantation, the success rate of one-time implantation, and the postoperative curative effect were compared between two groups. RESULTS: All patients were followed up for 12 to 36 months, with an average of(20.00±6.38) months. The bleeding volume and the time of tail cap implantation in the universal screwdriver group were significantly lower thanthose in the ordinary screwdriver group (P<0.05);The one-time success rate (100%) of the universal screwdriver group was significantly higher than that of the ordinary screwdriver group (75.4%)(P< 0.05);at the last follow-up, the efficacy scores of two groups were improved compared with preoperatively, but the efficacy scores of the universal screwdriver group were significantly better than those of the ordinary screwdriver group(P<0.05). CONCLUSION: The universal screwdriver is easy to operate during the operation when using the cap of the femoral intramedullary nail, the operation time is shortened, the amount of bleeding is reduced, and the treatment effect is satisfactory.

Development and clinical application of universal screwdriver / 中国骨伤

OBJECTIVE@#To develop a universal screwdriver for sealing the end of the central hole of the femoral interlocking intramedullary nail, so as to shorten the operation time of the tail cap implantation of the intramedullary nail and improve the accuracy of implantation.@*METHODS@#Total 77 patients with intertrochanteric fractures underwent femoral interlocking intramedullary nail (FIIN) surgery from June 2018 to June 2019. There were 28 males and 49 females, aged 55 to 80 (76.22± 7.32) years old, and course of disease was 20 to 40 h. All patients were divided into universal screwdriver group (39 cases) and ordinary screwdriver group (38 cases) according to whether the self-developed universal screw was applicable during the operation. The blood loss during tail cap implantation, the time of tail cap implantation, the success rate of one-time implantation, and the postoperative curative effect were compared between two groups.@*RESULTS@#All patients were followed up for 12 to 36 months, with an average of(20.00±6.38) months. The bleeding volume and the time of tail cap implantation in the universal screwdriver group were significantly lower thanthose in the ordinary screwdriver group (@*CONCLUSION@#The universal screwdriver is easy to operate during the operation when using the cap of the femoral intramedullary nail, the operation time is shortened, the amount of bleeding is reduced, and the treatment effect is satisfactory.

Friction Marks of Stabbing Tools in Tires.

When receiving a stabbed tire for examination, forensic toolmark examiners can determine whether a suspect tool was used in a specific crime based on class-characteristics and individual-characteristics marks that have been left by the tool on the tire. This study discusses friction marks and their forensic value during the examination of a punctured tire. The term friction mark refers to the noticeable mark around the penetration area on a tire's surface. Tires designed to create high friction when contacting a road. Due to this design, friction is created between the stabbing tool shank and the sides of the hole. As a result of this friction, the shank of the stabbing tool wears the outer layer of tire around the hole. This leaves a friction mark whose general shape reflects the cross-sectional shape of the stabbing tool's shank. This phenomenon was observed and named by Locke (7) in his evaluation of tire puncture marks with knives. This article demonstrates the same phenomenon with other types of stabbing tools. Test stabs were produced with different tools representing a variety of cross-sectional shapes of shanks, and the resulting friction marks were photo-documented and discussed. Correlations between the various cross-sectional shapes and their corresponding friction marks are shown. Based on friction mark examination, the examiner: (i) can infer suspect tool shank cross-sectional shape with the evaluation of the friction mark shape and (ii) can deduce the maximum dimensions of the shank. This examination simplifies and accelerates the forensic comparison procedure and the investigation time.

Torsion Resistance of the Ball Head System Screw and Screwdriver for Angled Screw Channels on Implant Prosthetics.

The primary objective of this study was to determine the torsion resistance of the Ball Head System (BHS) screw and screwdriver set at 0°, 20°, and 30° angulations. The secondary objective was to compare the BHS set with the 1.3-mm hexagonal screwdriver system (HexS) at 20° and analyze the condition of the BHS after 10 and 30 iterations with 30 N·cm torque at 30° angulation. A workbench made from type 4 plaster with 6 steel implant replicas (external hexagon, 4.1 mm) inserted at 0°, 20°, and 30° angulation was designed. An analogical torque meter was used. The deformations produced on the whole set were examined by field emission scanning electron microscopy. A descriptive analysis was performed. The maximum torque performance for BHS at 30° angulation was 54 ± 12 N·cm. Most screws could be removed despite the deformations produced. At 20° angulation, the BHS set achieved an average torque resistance of 67 ± 12 N·cm, whereas the HexS failed at 45 ± 2 N·cm. Although the iterations performed at 30 N·cm torque and 20° angulation produced some deformations on BHS sets; these could be tightened and unscrewed. The BHS allows tightening at a torque of up to 54 N·cm. Under the same conditions, BHS showed more torque resistance than HexS. Deformation of BHS sets was directly related to the number of iterations.

Triggered EMG (T-EMG) Values of Pedicle Screws with a Powered Screwdriver vs A Standard Probe in Adolescent Idiopathic Scoliosis Do Not Agree: A Prospective Validation Study.

Triggered electromyography (t-EMG) is a common technique used during spinal instrumentation in surgery for adolescent idiopathic scoliosis. This study tests the validity of t-EMG values obtained with a standard ball-tipped probe after completion of screw placement versus t-EMG values obtained during screw insertion with a powered screwdriver. t-EMG values were collected for screws spanning T7-L5 using both a standard probe and a powered screwdriver. A power analysis determined that a sample size of 300 screws would provide enough precision to estimate limits of agreement within ±2 mA. A monopolar constant current stimulation technique (0.2 ms duration and 3.11 Hz stimulation rate) was used at each level. EMG was acquired with placement of bipolar pairs of subdermal needle electrodes. A Bland-Altman plot was used to assess agreement between threshold readings from the two techniques. Twenty-nine patients were enrolled in this study with 305 screws. t-EMG values measured using a powered screwdriver were on average 1 mA lower than values from a standard probe. When readings less than or equal to 20 mA were considered, the limits of agreement were approximately 4 and 7 mA overall. In total, 28/305 (9%) screws were removed and reinserted, 9/305 (3%) screws were redirected, and 3/305 (1%) screws were aborted based on t-EMG readings. Despite a small overall difference in t-EMG value between the standard probe and screwdriver, there was still large variability in agreement between the two techniques. t-EMG values obtained with a powered screwdriver during screw insertion are not interchangeable with values measured by a probe.

Quantitative Statistics and Identification of Tool-Marks.

This study was designed to establish a feature identification method of tool-mark 2D data. A uniform local binary pattern histogram operator was developed to extract the tool-mark features, and the random forest algorithm was adopted to identify these. The presented method was used to conduct five groups of experiments with a 2D dataset of known matched and nonmatched tool-marks made by bolt clippers, cutting pliers, and screwdrivers. The experimental results show that the proposed method achieved a high rate of identification of the tool-mark samples generated under identical conditions. The proposed method effectively overcomes the disadvantage of unstable illumination of 2D tool-mark image data and avoids the difficulty in mark inspection caused by manually preset parameters in the existing methods, thus reducing the uncertainty of inspected results.

Accidental Ingestion of an Implant Screwdriver: A Case Report and Literature Review.

Head and neck oncology patients are high risk for ingestion or aspiration of dental instruments during treatment, due to altered anatomy and sensation. This article describes a case report of accidental ingestion of an implant screwdriver during the prosthetic phase of oral rehabilitation of a 79 year old oncology patient. The management protocol is described which included referral to the medical Accident and Emergency department, where the object was safely removed from the stomach via endoscopy. A review of similar cases of ingestion/inhalation in the literature suggests implant screwdrivers should be retrieved as safe passage through the gastrointestinal system is not assured. Awareness of the medical history and risk factors should alert clinicians to be extra cautious, and preventative strategies should be implemented at all times. Preventative measures include ligation of instruments with floss/suture material, treatment in a more vertical position, and use of rubber dam where possible.