Accuracy and consistency of the visual diagnosis of exposed dentine on worn occlusal/incisal surfaces

Most indices for the assessment of wear of various aetiologies include the distinction between 'enamel still present' and 'dentine exposed' for grading. Since the visual diagnosis of exposed dentine has not yet been validated, the present study is a first attempt to investigate its accuracy and consistency. Sixty-one examiners (23 scientists, 18 university dentists and 20 dental students) were asked to diagnose 49 tooth areas with different grades of wear and to decide whether dentine was exposed (positive test) or not (negative test). Afterwards, the teeth were histologically evaluated. In 44 areas, dentine (also in all cases with minor wear) was exposed, and in 5 areas enamel was present. Overall sensitivity was 0.65, specificity 0.88 and the proportion of correct diagnoses was 0.67. The diagnosis 'dentine is exposed' was about 5 times as likely and the diagnosis 'dentine is not exposed' half as likely to come from an area with exposed dentine than from an enamel-covered area. The closeness of the visual diagnosis to the histological findings was only fair (kappa=0.27), no significant impact of professional experience was found. For inter- and intra-examiner agreement, kappa was 0.28 and 0.55, respectively. It was concluded that the diagnosis of exposed dentine is difficult.

Posterior Vertical Bite Reconstructions of Erosively Worn Dentitions and the "Stamp Technique" - A Case Series with a Mean Observation Time of 40 Months

PURPOSE In the present case series, the authors report on seven cases of erosively worn dentitions (98 posterior teeth) which were treated with direct resin composite. MATERIALS AND METHODS In all cases, both arches were restored by using the so-called stamp technique. All patients were treated with standardized materials and protocols. Prior to treatment, a waxup was made on die-cast models to build up the loss of occlusion as well as ensure the optimal future anatomy and function of the eroded teeth to be restored. During treatment, teeth were restored by using templates of silicone (ie, two "stamps," one on the vestibular, one on the oral aspect of each tooth), which were filled with resin composite in order to transfer the planned, future restoration (ie, in the shape of the waxup) from the extra- to the intraoral situation. Baseline examinations were performed in all patients after treatment, and photographs as well as radiographs were taken. To evaluate the outcome, the modified United States Public Health Service criteria (USPHS) were used. RESULTS The patients were re-assessed after a mean observation time of 40 months (40.8 ± 7.2 months). The overall outcome of the restorations was good, and almost exclusively "Alpha" scores were given. Only the marginal integrity and the anatomical form received a "Charlie" score (10.2%) in two cases. CONCLUSION Direct resin composite restorations made with the stamp technique are a valuable treatment option for restoring erosively worn dentitions.

Design of a semi-implantable hearing device for direct acoustic cochlear stimulation

A new hearing therapy based on direct acoustic cochlear stimulation was developed for the treatment of severe to profound mixed hearing loss. The device efficacy was validated in an initial clinical trial with four patients. This semi-implantable investigational device consists of an externally worn audio processor, a percutaneous connector, and an implantable microactuator. The actuator is placed in the mastoid bone, right behind the external auditory canal. It generates vibrations that are directly coupled to the inner ear fluids and that, therefore, bypass the external and the middle ear. The system is able to provide an equivalent sound pressure level of 125 dB over the frequency range between 125 and 8000 Hz. The hermetically sealed actuator is designed to provide maximal output power by keeping its dimensions small enough to enable implantation. A network model is used to simulate the dynamic characteristics of the actuator to adjust its transfer function to the characteristics of the middle ear. The geometry of the different actuator components is optimized using finite-element modeling.

The esophageal ECG as a novel technique for ambulant heart rhythm monitoring

Introduction: Diagnosing arrhythmias by conventional Holter-ECG can be cumbersome because of artifacts, skin irritation and poor P-waves. In contrast, esophageal electrocardiography (eECG) is promising due to the anatomic relationship of the esophagus to the atria and its favorable bioelectric properties. Methods used: In an ambulant setting, we recorded eECGs from 10 volunteers with a novel, highly-miniaturized eECG recorder that is worn discretely behind the ear (1.5×1.8×5cm, 22grams). The device continuously records two eECG leads during 3 days with 500Hz sampling frequency and 24-bit resolution. Results: Mean ± SD recording time was 21.7±19.6 hours (max. 60 hours). Test persons were not limited in daily activities (e.g. eating, speaking) and only complained mild discomfort during probe insertion, which subsided later on. During 99.8% of time, the recorder acquired signals appropriate for further analysis. In unfiltered data, QRS complexes and P-waves were identifiable during >98% of time. P waves had higher amplitudes as compared to surface ECG (0.71 ± 0.42mV vs. 0.16 ± 0.03mV, p = 0.004). No complications occurred. Conclusion: Ambulatory eECG recording is safe, well tolerated and promising due to excellent P-wave detection, overcoming some limitations of conventional Holter ECG.

Actigraphy in agitated patients with dementia : Monitoring treatment outcomes

Especially in pharmacotherapeutic research, a variety of methods to monitor behavioural and psychological symptoms of dementia (BPSD) are currently being discussed. To date, the most frequently used of these are clinical scales, which, however, are subjective and highly dependent on personnel resources. In our study, we tested the usefulness of actigraphy as a more direct and objective way to measure day-night rhythm disturbances and agitated behaviour.After a baseline assessment, 24 patients with probable dementia of the Alzheimer type (NINCDS-ADRDA) and agitated behaviour received either 3 mg melatonin (n=7), 2.5 mg dronabinol (n=7), or placebo (n=10) for two weeks. In addition, 10 young and 10 elderly healthy subjects were examined as a control group. Motor activity levels were assessed using an actigraph worn continuously on the wrist of the non-dominant hand. At the beginning and the end of the study, patients' Neuropsychiatric Inventory (NPI) scores were also assessed.In the verum group, actigraphic nocturnal activity (P=0.001), NPI total score (P=0.043), and NPI agitation subscale score (P=0.032) showed significant reductions compared to baseline. The treatment-baseline ratio of nocturnal activity (P=0.021) and treatment-baseline difference of the nocturnal portion of 24 h activity (P=0.012) were reduced. Patients' baseline activity levels were similar to those seen in healthy elderly subjects. Younger healthy subjects exhibited higher motor activity even at night. There was no correlation between actigraphy and NPI.Both actigraphic measures and the gold standard clinical scale were able to distinguish between the verum and placebo groups. However, because they did not correlate with each other, they clearly represent different aspects of BPSD, each of which reacts differently to therapy. As a result, actigraphy may well come to play an important role in monitoring treatment success in BPSD.

Effects of rivastigmine on actigraphically monitored motor activity in severe agitation related to Alzheimer's disease: a placebo-controlled pilot study

Acetylcholinesterase inhibitors (AChEIs) are effective in the treatment of cognitive symptoms in Alzheimer's disease (AD). Because the behavioral and psychological symptoms of dementia (BPSD) have also been attributed to central cholinergic deficits, we examined whether the AChEI rivastigmine can reduce motor activity as measured in a rater-independent manner by wrist actigraphy in agitated AD patients. A total of 20 consecutive AD inpatients (13 females, 7 males, 80.4+/-9.1 years, S.D.) were included from our geriatric psychiatry unit, all of whom were exhibiting agitated behavior not attributable to delirium. Patients were assigned randomly and in a single-blinded fashion to rivastigmine 3mg or placebo for 14 days. Motor activity levels were monitored using an actigraph worn continuously on the wrist of the non-dominant hand. At the beginning and end of the study, patients were assessed using the Neuropsychiatric Inventory (NPI) and Nurses' Observation Scale for Geriatric Patients (NOSGER). Patients in the rivastigmine group exhibited less agitation than placebo recipients on the NPI-agitation subscale, but not on NOSGER. Actigraphic measurements showed a tendency towards reduced motor activity in the rivastigmine group. Because rivastigmine usually exerts its main effects after a longer period of time, the short-term effects seen in our study justify further controlled clinical trials examining the use of rivastigmine in BPSD by means of actigraphy.

A Novel Implantable Hearing System with Direct Acoustic Cochlear Stimulation

A new implantable hearing system, the direct acoustic cochlear stimulator (DACS) is presented. This system is based on the principle of a power-driven stapes prosthesis and intended for the treatment of severe mixed hearing loss due to advanced otosclerosis. It consists of an implantable electromagnetic transducer, which transfers acoustic energy directly to the inner ear, and an audio processor worn externally behind the implanted ear. The device is implanted using a specially developed retromeatal microsurgical approach. After removal of the stapes, a conventional stapes prosthesis is attached to the transducer and placed in the oval window to allow direct acoustical coupling to the perilymph of the inner ear. In order to restore the natural sound transmission of the ossicular chain, a second stapes prosthesis is placed in parallel to the first one into the oval window and attached to the patient's own incus, as in a conventional stapedectomy. Four patients were implanted with an investigational DACS device. The hearing threshold of the implanted ears before implantation ranged from 78 to 101 dB (air conduction, pure tone average, 0.5-4 kHz) with air-bone gaps of 33-44 dB in the same frequency range. Postoperatively, substantial improvements in sound field thresholds, speech intelligibility as well as in the subjective assessment of everyday situations were found in all patients. Two years after the implantations, monosyllabic word recognition scores in quiet at 75 dB improved by 45-100 percent points when using the DACS. Furthermore, hearing thresholds were already improved by the second stapes prosthesis alone by 14-28 dB (pure tone average 0.5-4 kHz, DACS switched off). No device-related serious medical complications occurred and all patients have continued to use their device on a daily basis for over 2 years. Copyright (c) 2008 S. Karger AG, Basel.

[Gerodontic consultation service for hospitalized geriatric patients: diagnosis and therapy (II)]

The aim of the study was to report on oral, dental and prosthetic conditions as well as therapeutic measures for temporarily institutionalized geriatric patients. The patients were referred to the dentist since dental problems were observed by the physicians or reported by the patients themselves. This resulted in a selection among the geriatric patients; but they are considered to be representative for this segment of patients exhibiting typical signs of undertreatment. The main problem was the poor retention of the prosthesis, which was associated to insufficient masticatory function and poor nutrition status. Forty-seven percent of the patients were edentulous or had maximally two radicular rests out of function. Altogether 70% of the maxillary and 51% of the mandibular jaws exhibited no more teeth. Eighty-nine percent of the patients had a removable denture, and it was observed that maxillary dentures were regularly worn in contrast to mandibular dentures. The partially edentate patients had a mean number of ten teeth, significantly more in the manidublar than maxillary jaw. Treatment consisted mainly in the adaptation and repair of dentures, tooth extractions and fillings. Only few appointments (mostly two) were necessary to improve the dental conditions, resulting in low costs. Patients without dentures or no need for denture repair generated the lowest costs. Slightly more visits were necessary for patients with dementia and musculoskeletal problems. The present findings show that regular maintenance care of institutionalized geriatric patients would limit costs in a long-term perspective, improve the oral situation and reduce the need for invasive treatment.

[Rehabilitation of a periodontally compromised dentition with implant-supported zirconia bridges. Case report]

Clinical aspects of reconstruction with fix prosthesis and dental implants in a patient with a history of periodontitis is shown. A successful stabilization and rehabilitation of the periodontally involved dentition can be achieved with tooth-worn crown and bridge reconstructions. From a functional and aesthetic point of view the result may not be satisfying due to mobility and overlength of the teeth and open approximal spaces. Today, dentist and patient have often to weigh if teeth shall be maintained or replaced by dental implants. Thereby, both must be aware of the fact that in complex cases long-term success and aesthetic outcome may be difficult to predict. An intense discussion with the patient on his expectations, invasive treatment, risks with regard to biologic and prosthetic aspects is mandatory and must be based on the best scientific evidence available. The present case report shows different considerations and describes a radical solution which meets the patient's needs and is based on modern CAD-CAM technology.

Orthodontic retention procedures in Switzerland.

OBJECTIVE To survey retention procedures used in orthodontic practices in Switzerland. MATERIAL AND METHODS A questionnaire previously developed by Renkema et al. (2009) was sent to 223 Swiss orthodontists. The questionnaire comprised six parts, mainly containing multiple-choice questions. Information as to background education of the individual orthodontist, retention in general, frequency of different types of removable or bonded retainers that were used, retention pro- tocol, and the type and size of the wire used for bonded retainers was assessed. RESULTS The overall response rate was 65 percent. Most orthodontists placed a bonded retainer in the upper and lower arch, except when the upper arch was expanded during treatment or when extractions were performed in the upper arch, in which case they placed a combination of fixed and removable retainers. Opinions varied with regard to how many hours the removable retainers should be worn and the duration of the retention phase. As far as bonded retainers were concerned, 87 percent of the orthodontists preferred life-long retention. Ninety-three percent of the orthodontists considered that the development of a guide- line on retention procedures would be useful. CONCLUSIONS The choice of retention procedures is mostly based on orthodontists personal preference. A further research into the long-term effectiveness of individual retention protocols is needed.