The virtual patient in dental medicine

OBJECTIVES The aim of this Short Communication was to present a workflow for the superimposition of intraoral scan (IOS), cone-beam computed tomography (CBCT), and extraoral face scan (EOS) creating a 3D virtual dental patient. MATERIAL AND METHODS As a proof-of-principle, full arch IOS, preoperative CBCT, and mimic EOS were taken and superimposed to a unique 3D data pool. The connecting link between the different files was to detect existing teeth as constant landmarks in all three data sets. RESULTS This novel application technique successfully demonstrated the feasibility of building a craniofacial virtual model by image fusion of IOS, CBCT, and EOS under 3D static conditions. CONCLUSIONS The presented application is the first approach that realized the fusion of intraoral and facial surfaces combined with skeletal anatomy imaging. This novel 3D superimposition technique allowed the simulation of treatment planning, the exploration of the patients' expectations, and the implementation as an effective communication tool. The next step will be the development of a real-time 4D virtual patient in motion.

Systematic literature review of digital three-dimensional superimposition techniques to create virtual dental patients

PURPOSE Digital developments have led to the opportunity to compose simulated patient models based on three-dimensional (3D) skeletal, facial, and dental imaging. The aim of this systematic review is to provide an update on the current knowledge, to report on the technical progress in the field of 3D virtual patient science, and to identify further research needs to accomplish clinical translation. MATERIALS AND METHODS Searches were performed electronically (MEDLINE and OVID) and manually up to March 2014 for studies of 3D fusion imaging to create a virtual dental patient. Inclusion criteria were limited to human studies reporting on the technical protocol for superimposition of at least two different 3D data sets and medical field of interest. RESULTS Of the 403 titles originally retrieved, 51 abstracts and, subsequently, 21 full texts were selected for review. Of the 21 full texts, 18 studies were included in the systematic review. Most of the investigations were designed as feasibility studies. Three different types of 3D data were identified for simulation: facial skeleton, extraoral soft tissue, and dentition. A total of 112 patients were investigated in the development of 3D virtual models. CONCLUSION Superimposition of data on the facial skeleton, soft tissue, and/or dentition is a feasible technique to create a virtual patient under static conditions. Three-dimensional image fusion is of interest and importance in all fields of dental medicine. Future research should focus on the real-time replication of a human head, including dynamic movements, capturing data in a single step.

Assessment and management of dental erosion

Studies have shown a growing trend toward increasing prevalence of dental erosion, associated with the declining prevalence of caries disease in industrialized countries. Erosion is an irreversible chemical process that results in tooth substance loss and leaves teeth susceptible to damage as a result of wear over the course of an individual's lifetime. Therefore, early diagnosis and adequate prevention are essential to minimize the risk of tooth erosion. Clinical appearance is the most important sign to be used to diagnose erosion. The Basic Erosive Wear Examination (BEWE) is a simple method to fulfill this task. The determination of a variety of risk and protective factors (patient-dependent and nutrition-dependent factors) as well as their interplay are necessary to initiate preventive measures tailored to the individual. When tooth loss caused by erosive wear reaches a certain level, oral rehabilitation becomes necessary.

Mandibular implant overdentures followed for over 10 years: patient compliance and prosthetic maintenance

PURPOSE: The mandibular implant overdenture is a popular treatment modality and is well documented in the literature. Follow-up studies with a long observation period are difficult to perform due to the increasing age of patients. The present data summarize a long-term clinical observation of patients with implant overdentures. MATERIALS AND METHODS: Between 1984 and 1997, edentulous patients were consecutively admitted for treatment with an implant overdenture. The dentures were connected to the implants by means of bars or ball anchors. Regular maintenance was provided with at least one or two scheduled visits per year. Recall attendance and reasons for dropout were analyzed based on the specific history of the patient. Denture maintenance service, relining, repair, and fabrication of new dentures were identified, and complications with the retention devices specified separately. RESULTS: In the time period from 1984 to 2008, 147 patients with a total of 314 implants had completed a follow-up period of >10 years. One hundred one patients were still available in 2008, while 46 patients were not reexamined for various reasons. Compliance was high, with a regular recall attendance of >90%. More than 80% of dentures remained in continuous service. Although major prosthetic maintenance was rather low in relation to the long observation period, visits to a dental hygienist and dentist resulted in an annual visit rate of 1.5 and 2.4, respectively. If new dentures became necessary, these were made in student courses, which increased the treatment time and number of appointments needed. Complications with the retention devices consisted mostly of the mounting of new female retainers, the repair of bars, and the changing of ball anchors. The average number of events and the rate of prosthetic service with ball anchors were significantly higher than those with bars. Twenty-two patients changed from ball anchors to bars; 9 patients switched from a clip bar to a rigid U-shaped bar. CONCLUSIONS: This long-term follow-up study demonstrates that implant overdentures are a favorable solution for edentulous patients with regular maintenance. In spite of specific circumstances in an aging population, it is possible to provide long-term care, resulting in a good prognosis and low risk for this treatment modality. For various reasons the dropout rate can be considerable in elderly patients and prosthetic service must be provided regularly.

Assessment of smoking behaviour in the dental setting. A study comparing self-reported questionnaire data and exhaled carbon monoxide levels

The present study validated the accuracy of data from a self-reported questionnaire on smoking behaviour with the use of exhaled carbon monoxide (CO) level measurements in two groups of patients. Group 1 included patients referred to an oral medicine unit, whereas group 2 was recruited from the daily outpatient service. All patients filled in a standardized questionnaire regarding their current and former smoking habits. Additionally, exhaled CO levels were measured using a monitor. A total of 121 patients were included in group 1, and 116 patients were included in group 2. The mean value of exhaled CO was 7.6 ppm in the first group and 9.2 ppm in the second group. The mean CO values did not statistically significantly differ between the two groups. The two exhaled CO level measurements taken for each patient exhibited very good correlation (Spearman's coefficient of 0.9857). Smokers had a mean difference of exhaled CO values of 13.95 ppm (p < 0.001) compared to non-smokers adjusted for the first or second group. The consumption of one additional pack year resulted in an increase in CO values of 0.16 ppm (p = 0.003). The consumption of one additional cigarette per day elevated the CO measurements by 0.88 ppm (p < 0.001). Based on these results, the correlations between the self-reported smoking habits and exhaled CO values are robust and highly reproducible. CO monitors may offer a non-invasive method to objectively assess current smoking behaviour and to monitor tobacco use cessation attempts in the dental setting.

Clinical outcome of a short-term psychotherapeutic intervention for the treatment of dental phobia

Objective: Anxiety before receiving dental treatment is widespread. The aim of this investigation was to evaluate the effect of a brief psychologic treatment on adherence to the dental treatment regimen in patients with dental phobia. Method and Materials: Dental phobic patients (n = 160) received 3 sessions of cognitive behavioral therapy that consisted of stress management training and exposure to phobic stimuli. The outcome was determined in terms of 3 subsequent dental visits. Results: Participating patients had not visited a dental clinician for an average of 6 years. Comparison of patients who completed the psychologic treatment with those who dropped out showed that 68% of the former but also 52% of the latter adhered to the subsequent dental treatment regimen. The number of psychologic treatment sessions correlated significantly and positively with anxiety level before treatment. Conclusion: Short-term psychologic therapy of 3 sessions results in a success rate of 70% to adherence to dental treatment among dental phobic patients. Duration of avoidance of anxiety before treatment was not related to success in completing the trial. Nevertheless, the more intense the patient's phobia, the more psychotherapeutic sessions were necessary. (Quintessence Int 2007;38; E589-E596).

Performance of dental implants after staged sinus floor elevation procedures: 5-year results of a prospective study in partially edentulous patients

OBJECTIVES: The aim of this prospective study was to evaluate the 5-year performance and success rate of titanium screw-type implants with the titanium plasma spray (TPS) or the sand-blasted, large grit, acid-etched (SLA) surface inserted in a two-stage sinus floor elevation (SFE) procedure in the posterior maxilla. MATERIAL AND METHODS: A total of 59 delayed SFEs were performed in 56 patients between January 1997 and December 2001, using a composite graft with autogenous bone chips combined with deproteinized bovine bone mineral (DBBM) or synthetic porous beta-tricalcium phosphate (beta-TCP). After a healing period averaging 7.75 months, 111 dental implants were inserted. After an additional 8-14-week healing period, all implants were functionally loaded with cemented crowns or fixed partial dentures. The patients were recalled at 12 and 60 months for clinical and radiographic examination. RESULTS: One patient developed an acute infection in the right maxillary sinus after SFE and did not undergo implant therapy. Two of the 111 inserted implants had to be removed because of a developing atypical facial pain, and 11 implants were lost to follow-up and were considered drop-outs. The remaining 98 implants showed favorable clinical and radiographic findings at the 5-year examination. The peri-implant soft tissues were stable over time; the mean probing depths and mean attachment levels did not change during the follow-up period. The measurement of the bone crest levels (DIB values) indicated stability as well. Based on strict success criteria, all 98 implants were considered successfully integrated, resulting in a 5-year success rate of 98% (for TPS implants 89%, for SLA implants 100%). CONCLUSION: This prospective study assessing the performance of dental implants inserted after SFE demonstrated that titanium implants can achieve and maintain successful tissue integration with high predictability for at least 5 years of follow-up in carefully selected patients.

Fixed mandibular and maxillary implant rehabilitation in a fully edentulous patient: a case report

The complete dental rehabilitation of a patient with a failing dentition using fixed implant-supported prostheses requires carefully planned and well-sequenced treatment. This case report presents the treatment steps and sequencing for a patient in whom removable provisional prostheses were not an option. While an immediate loading protocol was used in the mandible, a staged approach featuring strategic extractions and implant placement in several phases was applied in the maxilla. The major advantage of this treatment protocol was that the patient was maintained in fixed prostheses throughout the treatment.

[The deaf patient--information for a barrier-free conversation with patients in dentistry]

There are about 650,000 people with hearing problems in Switzerland, 10,000 of whom use sign language. About 100,000 people are hard of hearing. Deaf patients require special treatment in the dental office as they have specific communication needs. This community, like many other minority groups, has a sign language and a culture of its own. To prevent misunderstandings it is therefore very important to provide solutions for an enhanced communication. However, guidelines for the communication with deaf dental patients are still missing. Successful communication between deaf patients and dentist is essential for effective care. This paper is concerned with providing background information and introducing recommendations for unrestricted dentist-patient communication. The aim of this article is to improve dentists' knowledge of the appropriate communication with this patient group.

Management of children with autism spectrum disorder in the dental setting: concerns, behavioural approaches and recommendations

OBJECTIVES This article reviews the present literature on the issues encountered while coping with children with autistic spectrum disorder from the dental perspective. The autistic patient profile and external factors affecting the oral health status of this patient population are discussed upon the existing body of evidence. MATERIAL AND METHODS The MEDLINE database was searched using the terms 'Autistic Disorder', 'Behaviour Control/methods', 'Child', 'Dental care for disabled', 'Education', 'Oral Health', and 'Pediatric Dentistry' to locate related articles published up to January 2013. RESULTS Most of the relevant studies indicate poor oral hygiene whereas they are inconclusive regarding the caries incidence in autistic individuals. Undergraduate dental education appears to determine the competence of dental professionals to treat developmentally disabled children and account partly for compromised access to dental care. Dental management of an autistic child requires in-depth understanding of the background of the autism and available behavioural guidance theories. The dental professional should be flexible to modify the treatment approach according to the individual patient needs.

Dental phobia is no contraindication for oral implant therapy

OBJECTIVES Dental phobia is a psychological disease and a possible contraindication for implant therapy. The study aimed to show that implant therapy in dental-phobic patients (DP, test group) after adequate psychological and dental pretreatment (PDPT) is successfully possible and results in a similar implant prognosis as in nonfearful patients (NF, control group). METHOD AND MATERIALS 15 DP with PDPT and 15 NF were treated with dental implants and were re-evaluated 2 to 4 years after denture-mounting regarding: alteration of dental anxiety (Hierarchical Anxiety Questionnaire [HAQ], Visual Analog Scale [VAS]), patient satisfaction and compliance, implant success, and peri-implant health. Statistical tests of non-inferiority DP versus NF were performed with Hodges-Lehmann estimators and respective one-sided 97.5% confidence intervals of Moses, and pairwise testings with Mann-Whitney test. RESULTS The DP test group rated its anxiety significantly lower at follow- up than at baseline (PHAQ < .001). However, at follow-up, anxiety was still higher in DP than in NF (PHAQ = .046; PVAS < .001). Implant success at follow-up was 100%. Oral health was equally good in DP and NF patients. At follow-up, all patients were satisfied with implant therapy, but compliance was better for NF (100%) than for DP (73% dental checkup; 67% dental hygienist). CONCLUSION Implant therapy can be successfully performed in DP patients with PDPT as phobia is not negatively influenced by the invasive implant therapy. However, motivation for professional maintenance programs remains challenging.

The implementation of a tobacco dependence education curriculum in a Swiss Dental Hygiene School - an 8-year review

OBJECTIVE The aim of our investigation was to review the implementation of a comprehensive tobacco dependence education (TDE) curriculum at the Medi School of Dental Hygiene (MSDH), Bern, Switzerland, 2001-2008. METHODS In 2001, new forms to record patients' tobacco use history and willingness to quit were created for all the MSDH patients. In 2002, a new theoretically based tobacco dependence treatment protocol was implemented into the MSDH curriculum. Students received instruction on how to provide brief tobacco use dependence interventions as well as maintain detailed records of patient tobacco use and cessation interventions for every smoker at all dental hygiene visits. RESULTS In 2002, 17 lecture hours were added to the following subjects: pathology, periodontology, preventive dentistry, pharmacology and psychology. During the same time period, 2213 patients (56.9% women) have visited the MSDH. Smoking status was recorded in 85.7% of all the patients (30.2% smokers). Brief tobacco use interventions were recorded in 36.8% of all smokers while 7.6% of these have reported to quit smoking. CONCLUSIONS Overall, the new TDE curriculum was successfully implemented and accepted by the MSDH faculty. Applications in the clinical practice, however, may still be improved to better identify smokers and increase initial and follow-up interventions potentially leading to higher quit rates.

Influence of rubber dam on objective and subjective parameters of stress during dental treatment of children and adolescents - a randomized controlled clinical pilot study

BACKGROUND Rubber dam is recommended for isolating the working field during adhesive dentistry procedures; however, dentists often omit rubber dam, particularly in paediatric dentistry, supposing that it would stress the patient. AIM The aim of this study was to evaluate stress parameters during a standardized dental treatment procedure performed with or without rubber dam. The treatment time was measured as a secondary outcome variable. DESIGN This study was designed as a randomized, controlled, clinical study with 72 patients (6-16 years; mean age, 11.1). During standardized fissure sealing procedures, objective parameters of stress (e.g., skin resistance, breath rate) were recorded. The operator's stress level was measured by pulse rate. Subjective pain (patients) and stress perception (operator) were evaluated by an interview. RESULTS The breath rate was significantly (P<0.05) lower and the skin resistance level was significantly higher during treatment with rubber dam compared to the control group. Subjective pain perception was significantly lower for the test group. The treatment time needed for the fissure sealing procedure was 12.4% less in the test group. CONCLUSION Isolation with rubber dam caused less stress in children and adolescents compared to relative isolation with cotton rolls if applied by an experienced dentist.

Partial lateralization of the nasopalatine nerve at the incisive foramen for ridge augmentation in the anterior maxilla prior to placement of dental implants: a retrospective case series evaluating self-reported data and neurosensory testing

The objective of this study was to assess implant therapy after a staged guided bone regeneration procedure in the anterior maxilla by lateralization of the nasopalatine nerve and vessel bundle. Neurosensory function following augmentative procedures and implant placement, assessed using a standardized questionnaire and clinical examination, were the primary outcome variables measured. This retrospective study included patients with a bone defect in the anterior maxilla in need of horizontal and/or vertical ridge augmentation prior to dental implant placement. The surgical sites were allowed to heal for at least 6 months before placement of dental implants. All patients received fixed implant-supported restorations and entered into a tightly scheduled maintenance program. In addition to the maintenance program, patients were recalled for a clinical examination and to fill out a questionnaire to assess any changes in the neurosensory function of the nasopalatine nerve at least 6 months after function. Twenty patients were included in the study from February 2001 to December 2010. They received a total of 51 implants after augmentation of the alveolar crest and lateralization of the nasopalatine nerve. The follow-up examination for questionnaire and neurosensory assessment was scheduled after a mean period of 4.18 years of function. None of the patients examined reported any pain, they did not have less or an altered sensation, and they did not experience a "foreign body" feeling in the area of surgery. Overall, 6 patients out of 20 (30%) showed palatal sensibility alterations of the soft tissues in the region of the maxillary canines and incisors resulting in a risk for a neurosensory change of 0.45 mucosal teeth regions per patient after ridge augmentation with lateralization of the nasopalatine nerve. Regeneration of bone defects in the anterior maxilla by horizontal and/or vertical ridge augmentation and lateralization of the nasopalatine nerve prior to dental implant placement is a predictable surgical technique. Whether or not there were clinically measurable impairments of neurosensory function, the patients did not report them or were not bothered by them.