Conventional Mechanical Instruments Research Articles

An evaluation of diode laser as an adjunct to scaling and root planning in the nonsurgical treatment of chronic periodontitis: A clinico-microbiological study

Introduction: Laser is an acronym for light amplification by stimulated emission of radiation. They are being developed for a variety of uses in periodontal therapy. The diode laser in dentistry is used for treatment of diseased periodontal soft tissue, allowing significant bacterial reduction, and removal of the inflammatory products while creating excellent hemostasis. A flexible fiber optic delivery system allows the clinician easy and safe access around the periodontal pocket. The wavelengths are transmitted through water and are very poorly absorbed in apatite crystals, making them an excellent choice to use in a periodontally involved sulcus that has inflamed tissue and pigmented bacteria. This study was undertaken to evaluate the effectiveness of diode laser as an adjunct to scaling and root planing (SRP) in the nonsurgical treatment of chronic periodontitis. Aim: To evaluate the effectiveness of diode laser on plaque index (PI), gingival index (GI) probing pocket depth (PPD) and clinical attachment level (CAL) in chronic periodontitis patients and to compare the outcome with SRP alone. To evaluate the efficacy of diode laser on plaque microorganisms namely Aggregatibacter actinomycetemcomitans and Prevotella intermedia. Materials and Methods: A total number of 20 generalized chronic periodontitis patients were selected for the study. A randomized split-mouth design was followed to assign quadrants in each to one of the two treatment groups: SRP alone (Group I control group) and diode laser as an adjunct to SRP (Group II test group). The assessment of clinical parameters was carried out at baseline, day 30, 90, and 180. The microbiological analysis was done prior to the start of the treatment at baseline, day 15, 30, 90, and 180, respectively. Results: At baseline mean colony count was equal in both groups, however, at all the subsequent time intervals, mean colony count was lower in Group II as compared to Group I. All the groups showed statistically significant reduction in relation to PI, GI, PPD, CAL, and microbial count. Discussion: In this study, an attempt was made to evaluate the adjunctive role of diode lasers on gingival inflammation, pocket probing depth, the level of clinical attachment, and microbial count in relation to SRP using a case-control design. Recently, the use of laser has emerged as an adjunctive procedure in enhancing the clinical outcome of the periodontal treatment. It is one of the most promising new technical modalities for nonsurgical periodontal treatment and has an advantage of reaching sites that cannot be approached by conventional mechanical instrumentation. Conclusion: In the present study, an attempt was made to evalute the adjunctive role of diode lasers on plaque index, gingival index, pocket probing depth, level of clinical attachment and microbial count in relation to scaling and root planning using a case-control design. On the basis of these findings, adjunctive treatment with diode laser at a higher but clinically safe frequency (940nm) at repeated intervals showed a better efficacy in ensuring a better periodontal health as compared to SRP alone.

Computer-assisted navigation for cruciate-retaining total knee arthroplasty in patients with advanced valgus arthritic knees

BackgroundThe valgus arthritic knee is a complex deformity involving both soft tissue and bony problems that significantly affect the positioning of the components for, and decrease the accuracy of, reconstructed alignment in total knee arthroplasty (TKA). The unique bony deformity and soft tissue problem makes the use of conventional mechanical instrumentation difficult and leads to unsatisfactory results. PurposeThe purpose of this study was to investigate the effect of computer-assisted navigation for TKA on the postoperative mechanical axis, component alignment, and functional outcomes in the arthritic knee with genu valgus deformity. MethodsFrom January 2003 to August 2009, 24 patients (24 knees) with advanced valgus knee arthritis who underwent computer-assisted navigation for cruciate-retaining TKA were retrospectively reviewed. The accuracy of the postoperative mechanical axis and component alignment, and functional outcomes were assessed. ResultsThe mean postoperative mechanical axis was 180.2° (range, 178.1–182.5°). All patients achieved the targeted goal of a leg axis within 3° of the neutral axis. The joint line was not substantially elevated. No patient required conversion to a constrained component to achieve stability. At a mean follow-up of 45.5 months, the Hospital for Special Surgery (HSS) knee score improved from a mean preoperative score of 55.6 to 92.8 postoperatively. The International Knee Society (IKS) clinical score improved from 42.2 to 95.9. The IKS for pain improved from 15.4 to 47.1, and the IKS knee function score improved from 35.8 to 95.4. ConclusionComputer-assisted navigation for TKA is a useful alternative technique for advanced valgus knee arthritis where accurate restoration of the joint line, proper alignment of the limb and prosthetic components, and meticulous soft tissue balancing may be challenging because of bony deformities and soft tissue contractures.

Computer-Assisted Orthopaedic Surgery and Robotic Surgery in Total Hip Arthroplasty

Various systems of computer-assisted orthopaedic surgery (CAOS) in total hip arthroplasty (THA) were reviewed. The first clinically applied system was an active robotic system (ROBODOC), which performed femoral implant cavity preparation as programmed preoperatively. Several reports on cementless THA with ROBODOC showed better stem alignment and less variance in limb-length inequality on radiographic evaluation, less incidence of pulmonary embolic events on transesophageal cardioechogram, and less stress shielding on the dual energy X-ray absorptiometry analysis than conventional manual methods. On the other hand, some studies raise issues with active systems, including a steep learning curve, muscle and nerve damage, and technical complications, such as a procedure stop due to a bone motion during cutting, requiring re-registration and registration failure. Semi-active robotic systems, such as Acrobot and Rio, were developed for ease of surgeon acceptance. The drill bit at the tip of the robotic arm is moved by a surgeon's hand, but it does not move outside of a milling path boundary, which is defined according to three-dimensional (3D) image-based preoperative planning. However, there are still few reports on THA with these semi-active systems. Thanks to the advancements in 3D sensor technology, navigation systems were developed. Navigation is a passive system, which does not perform any actions on patients. It only provides information and guidance to the surgeon who still uses conventional tools to perform the surgery. There are three types of navigation: computed tomography (CT)-based navigation, imageless navigation, and fluoro-navigation. CT-based navigation is the most accurate, but the preoperative planning on CT images takes time that increases cost and radiation exposure. Imageless navigation does not use CT images, but its accuracy depends on the technique of landmark pointing, and it does not take into account the individual uniqueness of the anatomy. Fluoroscopic navigation is good for trauma and spine surgeries, but its benefits are limited in the hip and knee reconstruction surgeries. Several studies have shown that the cup alignment with navigation is more precise than that of the conventional mechanical instruments, and that it is useful for optimizing limb length, range of motion, and stability. Recently, patient specific templates, based on CT images, have attracted attention and some early reports on cup placement, and resurfacing showed improved accuracy of the procedures. These various CAOS systems have pros and cons. Nonetheless, CAOS is a useful tool to help surgeons perform accurately what surgeons want to do in order to better achieve their clinical objectives. Thus, it is important that the surgeon fully understands what he or she should be trying to achieve in THA for each patient.

Limb Alignment Improves with Computer-Assisted Navigation in Total Knee Replacement, But Questions Remain

The value of intraoperative computer navigation during total knee arthroplasty has been debated for more than a decade. Despite substantial research, contradictory results and reservations about the cost and efficacy of the technology have contributed to the failure of computer navigation to become the accepted standard for establishing limb alignment during knee replacement surgery. In their paper, Zhang and colleagues report the results of a well-designed, prospective, randomized study that was conducted to compare the short-term clinical and radiographic results of total knee arthroplasty performed with computer navigation with the results of total knee arthroplasty performed with conventional mechanical instruments. The authors attempted to control for as many variables as possible by studying patients with bilateral knee arthritis who were undergoing simultaneous bilateral knee replacement. For each patient, both the order of the surgery and the knee that was assigned to the computer-navigation group were selected by randomization. During the follow-up period, the clinician, radiologist, and patient were blinded with regard to the type of procedure that had been performed on each knee. The outcomes recorded included overall limb alignment on full-length radiographs; various parameters of prosthetic positioning on both standard radiographs and …

Ultraschallbasiertes Knochenschneiden in der Oralchirurgie: eine Übersicht anhand von 60 Patientenfällen

Surgical reconstruction of bony defects in the oral cavity can often be challenging since thin and fragile bony structures are especially prone to fracture cased by bulky cutting tips or the application of significant pressure by conventional mechanical instruments. The risk of accidental damage to adjacent soft tissue structures, such as nerves, by a dental drill or saw is also extremely high. The use of modulated ultrasound (piezosurgery) makes it possible to overcome such complications as a result of the precise and minimally invasive surgery technique which is limited to mineralized hard tissue. In 60 patients (38 male, 22 female) a piezosurgery device was used for different bone augmentation procedures before dental implant placement. The instrument uses modulated ultrasound (25 - 30 kHz) and the amplitude of the working tip ranges from 60 mum to 200 mum. The device was employed for sinus floor elevation (25), alveolar ridge augmentation using an autogenous block graft (25), alveolar ridge splitting (5) or lateralization of the alveolar nerve (5). Physiological sodium chloride was used as a cooling solution. For all osteotomies mode boosted burst c and pump 5 were used. Piezoelectric osteotomy permitted micrometric selective cutting and a clear surgical site due to the cavitation effect created by the cooling solution and the oscillating tip. No excessive bleeding was encountered. The risk of accidental soft tissue harm, such as perforating the sinus membrane or damaging adjacent nerves, was definitely lower than in the case of a conventional bur. No serious complications were encountered in the postoperative wound healing process after 2, 14, 30 and 90 days. However, the surgical procedures were time-consuming. Piezosurgery is an advantageous osteotomy technique for delicate structures in the oral and maxillofacial region. With respect to osteotomies of thin and fragile bones, the application of ultrasound is superior to other mechanical instruments because of the extremely precise and virtually arbitrary cut geometries, easy handling, efficient bone ablation and minimal accidental damage to adjacent soft tissue structures.

Bone Healing After Piezosurgery and its Influence on Clinical Applications

Osteotomies are well-established procedures in oral and maxillofacial surgery for either corrective measures or for gaining access to subjacent hard and soft tissues. Yet surgical reconstruction of bony defects can often be very challenging as thin and fragile bony structures are especially prone to fracture due to bulky cutting tips or massive application of pressure by conventional mechanical instruments. By employing the new technique of piezosurgery such complications can be overcome. It was the aim of this animal study to analyse the bone remodelling process after ultrasound osteotomy in the sheep tibia under functional loading after 8 and 12 weeks and to evaluate its impact on clinical applications.

Computer-Assisted Navigation Increases Precision of Component Placement in Total Knee Arthroplasty

In our clinical study, 200 total knee arthroplasties were evaluated to compare the use of the OrthoPilot system with conventional mechanical instrumentation. Long-term outcome of total knee replacement depends mainly on the accuracy of implant positioning and restoration of the mechanical leg axis. Our experience was that navigation could achieve a greater degree of accuracy concerning the aforementioned aspects. Among 513 primary-inserted total knee replacements, 100 navigated knees were compared with 100 conventionally implanted knees after matching the two groups of patients by gender, body mass index, age, preoperative deformities, radiographic findings, and operating time. Three weeks after surgery, the radiographic results were significantly better in the computer-assisted group compared with the results in the conventional group when we assessed component positioning in four axes. Only the sagittal tibial component angle was not significantly different. Total knee arthroplasty using the OrthoPilot system led to increased precision of tibial and femoral component positioning in comparison with hand-guided replacement surgery. An additional 10 minutes of operating time was acceptable. Navigation-specific complications were not seen, and the number of outliers decreased. Because computer navigation in orthopaedics is a new technology, data regarding long-term outcomes are not available. Diagnostic study, Level II-1 (retrospective study). See the Guidelines for Authors for a complete description of levels of evidence.

Pain related to mechanical and chemomechanical removal of caries in children

The objective of the present study is to compare the pain response associated with the chemomechanical method and hand excavation method during caries removal. Previous studies have indicated that a chemomechanical caries removal system (Carisolv™) has been effective in minimizing the use of conventional mechanical instruments and that it may reduce the need for local anaesthesia. In the present study, a comparison of the pain experienced during treatment with a chemomechanical tecnique and during conventional hand excavation method was carried out in 34 patients. Patients between 4 and 6 years of age were selected for the research. In our study, during the removal of caries some children felt pain both using the Carisolv system and hand excavation method (26.5% and 58.8%, respectively). In the Carisolv group 11.8% of the children wanted local anaesthesia to remove the pain which occurred during the operation; in the hand excavation group 23.5% wanted anaesthesia. In conclusion, the Carisolv system is effective in the removal of caries, causes less pain and need for anaesthesia, decreases the fear, anxiety and stress of children especially created by injectors and drills and increases cooperation.

Chemomechanical caries removal

The purpose of this paper was to introduce Carisolv? system for chemo-mechanical caries removal and its main characteristics, mechanism of action, clinical procedure and the efficacy of this alternative method. New materials and technical and technological development contributed to more precise and efficient work in dentistry. However, problems of rotary instruments for caries removal have remained. Chemomechanical method for caries removal was introduced thirty years ago as an alternative to the conventional mechanical instruments. The technique involved applying a solution onto the carious tissue, allowing it to soften and to remove it without use of drill. Its advantages were: selective removal of carious tissue, absence of pain, reduced need for local anesthesia and reduced potential negative effects to the dental pulp.