Evolution of surface morphology of Er:YAG laser-machined human bone

Use of a Fiberoptic-Laser Approach During Endoscopic Sinus Surgery: A Cadaver Feasibility Study

Aims

The aim of the present study is to evaluate the clinical applicability of laser energy during an oro-nasal endoscopic approach (ONEA) in the management of the anterior maxillary sinus wall.

Methods

An experiment on three adult human cadavers was performed to study the nasal cavities with angled rigid scopes and using the ONEA technique. In order to evaluate the effectiveness of laser energy on the bone, the drilling effect was compared to laser energy (1470 nm diode laser, continuous wave, power 8, 9 and 10 W).

Results

Compared to a rigid angled scope, the ONEA technique allowed complete visualization of the anterior wall of the maxillary sinus. Microscopic analysis of frontal bone revealed similar bone Exeresis with high-speed drilling (270.28 μm) and laser approaches (285.73-456.6 μm).

Conclusions

The laser ONEA technique is an innovative, mini-invasive, and safe approach to the anterior wall of the maxillary sinus. Additional study is warranted to further develop this technique.

Antibiotics Efficiency in the Infection Complications Prevention after Third Molar Extraction: A Systematic Review

(1) Background: Antibiotics are used in every medical field including dentistry, where they are used for the prevention of postoperative complications in routine clinical practice during the third molar extraction. (2) Methods: This study is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The present systematic review aimed to evaluate and systematize the use of antibacterial drugs in order to prevent postoperative complications in outpatient oral surgery for wisdom teeth extraction. We conducted a systematic review using electronic databases such as Medline PubMed, Scopus, and the Cochrane Central Register of Controlled Trials. Considering inclusion and exclusion criteria, we included randomized clinical trials published up to 2021 investigating the antibiotic prescription for third molar extraction. (3) Results: We selected 10 studies after the application of inclusion and exclusion criteria. The results showed that the most widely used antibiotic was amoxicillin both with and without clavulanic acid, in different dosages and duration. There were no statistically significant differences between treatment groups for development of postoperative complications. (4) Conclusions: Based on the analysis of the included studies, penicillin is currently the most widely prescribed group of antibiotics. The widespread use of this antibiotic group can lead to antimicrobial resistance (AMR). Due to increasing prevalence of bacteria resistance to penicillins, clinicians should carefully prescribe these antibiotics and be aware that the widespread use of amoxicillin may do more harm than good for the population.

Cold Ablation Robot-Guided Laser Osteotome (CARLO®): From Bench to Bedside

Background: In order to overcome the geometrical and physical limitations of conventional rotating and piezosurgery instruments used to perform bone osteotomies, as well as the difficulties in translating digital planning to the operating room, a stand-alone robot-guided laser system has been developed by Advanced Osteotomy Tools, a Swiss start-up company. We present our experiences of the first-in-man use of the Cold Ablation Robot-guided Laser Osteotome (CARLO^®). Methods: The CARLO^® device employs a stand-alone 2.94-µm erbium-doped yttrium aluminum garnet (Er:YAG) laser mounted on a robotic arm. A 19-year-old patient provided informed consent to undergo bimaxillary orthognathic surgery. A linear Le Fort I midface osteotomy was digitally planned and transferred to the CARLO^® device. The linear part of the Le Fort I osteotomy was performed autonomously by the CARLO^® device under direct visual control. All pre-, intra-, and postoperative technical difficulties and safety issues were documented. Accuracy was analyzed by superimposing pre- and postoperative computed tomography images. Results: The CARLO^® device performed the linear osteotomy without any technical or safety issues. There was a maximum difference of 0.8 mm between the planned and performed osteotomies, with a root-mean-square error of 1.0 mm. The patient showed normal postoperative healing with no complications. Conclusion: The newly developed stand-alone CARLO^® device could be a useful alternative to conventional burs, drills, and piezosurgery instruments for performing osteotomies. However, the technical workflow concerning the positioning and fixation of the target marker and the implementation of active depth control still need to be improved. Further research to assess safety and accuracy is also necessary, especially at osteotomy sites where direct visual control is not possible. Finally, cost-effectiveness analysis comparing the use of the CARLO^® device with gold-standard surgery protocols will help to define the role of the CARLO^® device in the surgical landscape.

First-in-man application of a cold ablation robot guided laser osteotome in midface osteotomies

The aim of the study was to assess the clinical applicability of robot guided laser osteotomy for clinical application. This is the initial report on 14 consecutive patients requiring an orthognathic procedure with a midface osteotomy (no restrictions made on the surgical indication itself) who have undergone surgery by means of the Cold Ablation Laser Osteotome CARLO® (AOT Advanced Osteotomy Tools, Basle, Switzerland), which is an integrated system, functionally comprising: an Er:YAG laser source, intended to perform osteotomies using cold laser ablation, a robot arm that controls the position of the laser source, an optical tracking device that provides a continuous and accurate measurement of the position of the laser source and of reference elements attached to instruments or bones, a navigation system (software) that is able to read preoperatively defined planned osteotomies, and - under the control of a surgeon - performs the planned osteotomies. Safety was assessed by unimpaired postoperative healing and the absence of device related injuries; performance was assessed as ability to cut the maxilla along the preoperatively planned cutting path with a rage of accuracy of 2mm. Cold ablation robot-guided laser osteotomy could successfully be performed in 14 consecutive patients. No intraoperative complications or technical failure occurred. All osteotomies were within an average deviation of 0.80 mm (±0.26 mm) of the virtually preplanned location. The registration procedure to set up the robot at the beginning of the operation required a mean time of 4.6 min (±5.3min). In this report we describe the effective and successful routine use of Cold ablation robot-guided laser osteotomy in an actual clinical setting. It is a promising technical innovation that has the potential to set new standards for accuracy and safety in orthognathic surgery.

Thermal Assessment of Ex Vivo Laser Ablation of Cortical Bone

As a potential osteotomy tool, laser ablation is expected to provide rapid machining of bone, while generating minimal thermal damage (carbonization) and physical attributes within the machined region conducive to healing. As these characteristics vary with laser parameters and modes of laser operation, the clinical trials and in vivo studies render it difficult to explore these aspects for optimization of the laser machining parameters. In light of this, the current work explores various thermal and microstructural aspects of laser-ablated cortical bone in ex vivo study to understand the fundamentals of laser-bone interaction using computational modeling. The study employs the Yb-fiber Nd:YAG laser (λ = 1064 nm) in the continuous wave mode to machine the femur section of bovine bone by a three-dimensional machining approach. The examination involved thermal analysis using differential scanning calorimetry and thermogravimetry, phase analysis using X-ray diffractometry, qualitative analysis using X-ray photoelectron spectroscopy, and microstructural and semiquantitative analysis using scanning electron microscopy equipped with energy-dispersive spectrometry. The mechanism of efficient bone ablation using the Nd:YAG laser was evaluated using the computational thermokinetics outcome. The use of high laser fluence (10.61 J/mm²) was observed to be efficient to reduce the residual amorphous carbon in the heat-affected zone while achieving removal of the desired volume of the bone material at a rapid rate. Minimal thermal effects were predicted through computational simulation and were validated with the experimental outcome. In addition, this work reveals the in situ formation of a scaffold-like structure in the laser-machined region which can be conducive during healing.