Ergonomics in dentistry: experiences of the practice by dental students

OBJECTIVE

The aim of this study was to qualitatively evaluate the experiences of students enrolled in the last year of dentistry school with ergonomic practice.

METHODS

This is a qualitative, observational and cross-sectional study, with a non-probabilistic sample design. The sample comprised students enrolled in the last year of dentistry in Araraquara-UNESP (n = 29). The data were collected by means of open semi-structured and individual interviews, captured by a digital voice recorder. The students were interviewed in their own university at a time that was previously scheduled, and care was taken to provide a private and welcoming environment to carry out the interviews. A script containing questions related to practices in ergonomics was prepared at the university. Data analysis was carried out using the qualitative-quantitative Collective Subject Discourse technique with the aid of Qualiquantisoft^® software program.

RESULTS

It was found that more than half of the students (58.6%) believe that adopting an ergonomic posture is important to prevent future problems, pain and occupational diseases, and 62.1% of the students confirm having difficulties in adopting ergonomic postures due to the types of treatment required and the regions of the mouth being treated. The main reasons stated for the fact that their colleagues do not adopt ergonomic postures are lack of attention, practice and forgetfulness (44.8%) and difficulty in visualising the operatory field or the procedure performed (27.6%).

CONCLUSION

It is possible to conclude that the students interviewed know ergonomic principles and their importance in occupational health. However, they found it difficult to put these principles into practice.

Dental optical tomography with upconversion nanoparticles-a feasibility study

Upconversion nanoparticles (UCNPs) have the unique ability to emit multiple colors upon excitation by near-infrared (NIR) light. Herein, we investigate the potential use of UCNPs as contrast agents for dental optical tomography, with a focus on monitoring the status of fillings after dental restoration. The potential of performing tomographic imaging using UCNP emission of visible or NIR light is established. This in silico and ex vivo study paves the way toward employing UCNPs as theranostic agents for dental applications.

Nanotechnology in Dentistry: Clinical Applications, Benefits, and Hazards

Nanotechnology is emerging as an interdisciplinary field that is undergoing rapid development and has brought about enormous changes in medicine and dentistry. Nanomaterial-based design is able to mimic some of the mechanical and structural properties of native tissue and can promote biointegration. Nanotechnology has various applications in dentistry, including dentition renaturalization, therapy for dentin hypersensitivity, complete orthodontic realignment in a single visit, covalently bonding diamondized enamel, enhancing properties of root canal sealers, and continuous oral health maintenance using mechanical dentifrobots. A range of synthetic nanoparticles such as hydroxyapatite, bioglass, titanium, zirconia, and silver nanoparticles are proposed for dental restoration. This review focuses on the developments in the field of nanomaterials in dentistry in the form of tissue regeneration materials, implantable devices, nanocomposites, endodontic sealers etc. and issues of patient safety.

A Systematic Method for" "Accurate Functional Diagnosis

The "medical model" is a term coined for a set of procedures in which American physicians are trained. For dentistry, the sequentially ordered set of procedures includes: (1) immediate concerns; (2) medical/ dental histories; (3) physical examination findings; (4) ancillary tests, if needed; (5) diagnosis; (6) risk assessment; (7) prognosis without treatment; (8) treatment-plan options/informed consent; (9) treatment; (10) post-treatment assessment and verification. This case report demonstrates a diagnostic system using the medical model via linear thinking-ie, step-by-step progression-to diagnose and conservatively treat a patient with a constricted chewing pattern.

Effectiveness of Hypnosis in Combination with Conventional Techniques of Behavior Management in Anxiety/Pain Reduction during Dental Anesthetic Infiltration

Background and Objective. Anxiety/pain are experiences that make dental treatment difficult for children, especially during the time of anesthesia. Hypnosis is used in pediatric clinical situations to modify thinking, behavior, and perception as well as, recently, in dentistry; therefore the aim of this study was to evaluate the effectiveness of hypnosis combined with conventional behavior management techniques during infiltration anesthetic. Methods. Anxiety/pain were assessed with the FLACC scale during the anesthetic moment, as well as heart rate variability and skin conductance before and during the anesthetic moment, between the control and experimental group. Results. A marginal statistical difference (p = 0.05) was found in the heart rate between baseline and anesthetic moment, being lower in the hypnosis group. No statistically significant differences were found with the FLACC scale or in the skin conductance (p > 0.05). Conclusion. Hypnosis combined with conventional behavior management techniques decreases heart rate during anesthetic infiltration showing that there may be an improvement in anxiety/pain control through hypnotic therapy.

Generation of 3D thermal models for dentistry applications

There are a variety of medical imaging modalities available, although each modality focus into different aspects, for example: anatomical, physiological or geometrical information. This paper presents a new imaging modality (3D THERMO-SCAN) that combines anatomical computer tomography (CT) imaging slices, together with 2D infrared thermography images and 3D scanned shaped models of the area under study. Therefore, it is presented the 3D reconstructions involving a case study of a volunteer with bruxism. Some characteristics of bruxism are the hyperactivity of the chewing muscles, which changes the dynamics of microcirculation, also changing the correspondent skin's temperature. The emphasis is to show the corresponding structures, such as jaw/mandibular region that will produce either decrease or increase in temperature, which are related to bruxism and the associated use of an occlusal splint, respectively.

[Ocular complications of local anaesthesia in dentistry]

An estimated 1 in 1,000 local anaesthetic injections in the maxilla or the mandible lead to unwanted effects on the ipsilateral eye. We have seen a case with diplopia and lateral rectus palsy following bimaxillary anaesthesia. A systematic literature review of reports on this type of complication resulted in a total of 144 documented cases published between 1936 and 2016. The most frequently reported symptoms included diplopia (72%), partial or full ophthalmoplegia (26%), ptosis (22%), mydriasis (18%), amaurosis (13%) and orbital pain (12%). This type of complication is best understood by pathophysiological hypotheses that include intra-arterial injection, intravenous injection, autonomic dysregulation, or deep injection and diffusion. If ocular symptoms appear after local intraoral anaesthesia, the patient should be reassured. In the case of diplopia, the eye should be covered with a gauze dressing, and the patient should be instructed about associated safety risks. If symptoms persist or when vision deteriorates, referral to an ophthalmologist is advisable.

Developing Customized Dental Miniscrew Surgical Template from Thermoplastic Polymer Material Using Image Superimposition, CAD System, and 3D Printing

This study integrates cone-beam computed tomography (CBCT)/laser scan image superposition, computer-aided design (CAD), and 3D printing (3DP) to develop a technology for producing customized dental (orthodontic) miniscrew surgical templates using polymer material. Maxillary bone solid models with the bone and teeth reconstructed using CBCT images and teeth and mucosa outer profile acquired using laser scanning were superimposed to allow miniscrew visual insertion planning and permit surgical template fabrication. The customized surgical template CAD model was fabricated offset based on the teeth/mucosa/bracket contour profiles in the superimposition model and exported to duplicate the plastic template using the 3DP technique and polymer material. An anterior retraction and intrusion clinical test for the maxillary canines/incisors showed that two miniscrews were placed safely and did not produce inflammation or other discomfort symptoms one week after surgery. The fitness between the mucosa and template indicated that the average gap sizes were found smaller than 0.5 mm and confirmed that the surgical template presented good holding power and well-fitting adaption. This study addressed integrating CBCT and laser scan image superposition; CAD and 3DP techniques can be applied to fabricate an accurate customized surgical template for dental orthodontic miniscrews.

SensInDenT-Noncontact Sensors Integrated Into Dental Treatment Units

This paper presents the first system design (SensInDenT) for noncontact cardiorespiratory monitoring during dental treatment. The system is integrated into a dental treatment unit, and combines sensors based on electromagnetic, optical, and mechanical coupling at different sensor locations. The measurement principles and circuits are described and a system overview is presented. Furthermore, a first proof of concept is provided by taking measurements in healthy volunteers under laboratory conditions.

A teledentistry system for the second opinion

In this paper we present a Teledentistry system aimed to the Second Opinion task. It make use of a particular camera called intra-oral camera, also called dental camera, in order to perform the photo shooting and real-time video of the inner part of the mouth. The pictures acquired by the Operator with such a device are sent to the Oral Medicine Expert (OME) by means of a current File Transfer Protocol (FTP) service and the real-time video is channeled into a video streaming thanks to the VideoLan client/server (VLC) application. It is composed by a HTML5 web-pages generated by PHP and allows to perform the Second Opinion both when Operator and OME are logged and when one of them is offline.

Does the 'inverse screening law' apply to oral cancer screening and regular dental check-ups?

Objective: Early detection through regular screening is a measure used in certain cancer prevention strategies. This approach has been advocated for the prevention of oral cancers in the UK. The objective of this study was to assess whether people at higher risk of oral cancer in the UK visit dentists on a regular basis, and thereby afford opportunities for oral cancer screening.

Methods: Data from two large national surveys were used. Firstly, data from the Health Survey for England, 2001, were used to assess the relationship between dental attendance (the outcome measure) and recognized oral cancer risk factors; there were 13,784 participants with complete data. We used known risk factors for oral cancer (age >40 years, male sex, alcohol intake >28 units per week, cigarettes >20 per day, and fruit and vegetables <5 times a day) to generate a risk score for oral cancer. Logistic regression was used to compute the odds ratios for regular dental attendance according to risk score. All analyses used education and social class as covariates. We also used data from the British Household Panel Survey to assess whether dental attendance behaviour is sustained over a set period of time (5547 participants with complete data).

Results: In persons in the higher risk category (as defined above) of the five risk factors, age, sex, alcohol, smoking, and fruit/vegetables, 68%, 56%, 52%, 43% and 60%, respectively reported regular dental check-ups. In persons with 0, 1, 2, 3, 4 and 5 of these risk factors, the odds ratio for regular dental check-ups was 1.00, 0.93, 0.81, 0.64, 0.50 and 0.28, respectively. The probability of regular dental attendance was low in all groups with a higher risk of oral cancer. In the longitudinal sample, the low probability of visiting a dentist regularly was stable over time.

Conclusion: Opportunistic screening for oral cancer in general dental practice in the UK is unlikely to be an effective preventive strategy.

[Navigation in implantology: Accuracy assessment regarding the literature]

Our objective was to assess the literature regarding the accuracy of the different static guided systems. After applying electronic literature search we found 661 articles. After reviewing 139 articles, the authors chose 52 articles for full-text evaluation. 24 studies involved accuracy measurements. Fourteen of our selected references were clinical and ten of them were in vitro (modell or cadaver). Variance-analysis (Tukey's post-hoc test; p < 0.05) was conducted to summarize the selected publications. Regarding 2819 results the average mean error at the entry point was 0.98 mm. At the level of the apex the average deviation was 1.29 mm while the mean of the angular deviation was 3,96 degrees. Significant difference could be observed between the two methods of implant placement (partially and fully guided sequence) in terms of deviation at the entry point, apex and angular deviation. Different levels of quality and quantity of evidence were available for assessing the accuracy of the different computer-assisted implant placement. The rapidly evolving field of digital dentistry and the new developments will further improve the accuracy of guided implant placement. In the interest of being able to draw dependable conclusions and for the further evaluation of the parameters used for accuracy measurements, randomized, controlled single or multi-centered clinical trials are necessary.

[Bactericid and fungicid polymers in dentistry. Polyethyleneimine, a new effective antibacterial and antifungal cationic polymer and its dental application]

In the past years antibacterial and antifungal polymers had become the focus of medical research. Polyethylenimine (PEI) and poliamidoamin had been proven the most effective polymers. The data shown in this short review discuss the chemical structure, pharmacological effects and medical use of PEI. Report in the international literature only gives examples of experimental dental appliance of PEI in sealers and filling materials. Because of the growing interest in the subject of PEI we find it important to inform the domestic dental society of cationic polymers.

Oral Manifestations of Inflammatory Bowel Diseases: Two Case Reports

Inflammatory bowel diseases (IBD) are known as chronic inflammatory disorders of the digestive tract, represented mainly by Crohn's disease (CD) and ulcerative colitis (UC). Among the main oral manifestations of IBD are cobblestoning of the oral mucosa, labial swellings with vertical fissures, pyostomatitis vegetans, angular cheilitis, perioral erythema, and glossitis. In this sense, understanding these nosological entities by dentists would help reach early and differential diagnosis. Thus, two case reports are presented and discussed based on theoretical references obtained by a literature review. The first case report refers to an adult patient whose IBD diagnosis was established after stomatological assessment. The second case was a patient with CD diagnosed in childhood with characteristic oral lesions.

Organic Nanomaterials and Their Applications in the Treatment of Oral Diseases

There is a growing interest in the development of organic nanomaterials for biomedical applications. An increasing number of studies focus on the uses of nanomaterials with organic structure for regeneration of bone, cartilage, skin or dental tissues. Solid evidence has been found for several advantages of using natural or synthetic organic nanostructures in a wide variety of dental fields, from implantology, endodontics, and periodontics, to regenerative dentistry and wound healing. Most of the research is concentrated on nanoforms of chitosan, silk fibroin, synthetic polymers or their combinations, but new nanocomposites are constantly being developed. The present work reviews in detail current research on organic nanoparticles and their potential applications in the dental field.

Potential use of snake venom derivatives as hemostatic agents in dentistry

This article reviews the hemostatic properties of snake venoms and their potential clinical application.

Simulations of thermal processes in tooth proceeding during cold pulp vitality testing

PURPOSE

This paper deals with the mathematical modeling of the thermal processes occurring in the tooth, during a very brief contact (a few seconds) with a very cold liquid on a part of the tooth crown. In this way one can simulate a heat transfer in tooth proceeding during a dental diagnostic test - pulp vitality testing. The impact of rapid ambient thermal changes acting on the tooth can cause toothache.

METHODS

The mathematical model: a system of partial differential equations with initial-boundary conditions (the axiallysymmetrical problem) and their numerical solutions using the control volume method is discussed.

RESULTS

Simulation results of the kinetics of the temperature changes inside the tooth are presented. The example of the control volume mesh (using the Voronoi polygons) well describing the shape of a molar tooth is given.

CONCLUSIONS

The simulation results (the temperature distribution in the tooth at any moment of the simulation time and the kinetics of temperature variation at the points of the tooth domain considered) can help dentists in the selection of an appropriate method of treatment.