Hypnosis and Local Anesthesia for Dental Pain Relief-Alternative or Adjunct Therapy?-A Randomized, Clinical-Experimental Crossover Study.

This prospective randomized clinical crossover trial was designed to compare hypnosis and local anesthesia for experimental dental pain relief. Pain thresholds of the dental pulp were determined. A targeted standardized pain stimulus was applied and rated on the Visual Analogue Scale (0-10). The pain threshold was lower under hypnosis (58.3 ± 17.3, p < .001), maximal (80.0) under local anesthesia. The pain stimulus was scored higher under hypnosis (3.9 ± 3.8) than with local anesthesia (0.0, p < .001). Local anesthesia was superior to hypnosis and is a safe and effective method for pain relief in dentistry. Hypnosis seems to produce similar effects observed under sedation. It can be used in addition to local anesthesia and in individual cases as an alternative for pain control in dentistry.

Effectiveness of Self-Hypnosis on the Relief of Experimental Dental Pain: A Randomized Trial.

This randomized, controlled clinical trial evaluates the effectiveness of self-hypnosis on pain perception. Pain thresholds were measured, and a targeted, standardized pain stimulus was created by electrical stimulation of the dental pulp of an upper anterior tooth. Pain stimulus was rated by a visual analogue scale (VAS). The pain threshold under self-hypnosis was higher (57.1 ± 17.1) than without hypnotic intervention (39.5 ± 11.8) (p < .001). Pain was rated lower on the VAS with self-hypnosis (4.0 ± 3.8) than in the basal condition without self-hypnosis (7.1 ± 2.7) (p < .001). Self-hypnosis can be used in clinical practice as an adjunct to the gold standard of local anesthesia for pain management, as well as an alternative in individual cases.

Contrast curves of five different intraoral X-ray sensors: a technical note.

OBJECTIVES: The aim of this article is to compare the contrast and resolution properties of five different sensors using a known technical target. METHODS: Stripe patterns with defined amounts of line pairs per mm (2.5-20 LP/mm) were recorded using five commercial digital sensors. Image data were analyzed using ImageJ and MatLab to calculate different contrast curves using logistic regression. RESULTS: The Dexis Platinum Sensor reached a calculated 10% contrast at 29.52 LP/mm. The Duerr VistaRay 6 Sensor reached a 10% contrast at 9.9 LP/mm. The 10% contrast was found at 18.8 LP/mm for the Duerr VistaRay 7. The Sirona Xios+ Sensor reached a calculated 10% contrast at 13.9 LP/mm. The Sirona Fullsize charge-coupled device (CCD) Sensor exhibited 10% contrast at 10.3 LP/mm. CONCLUSIONS: The contrast transfer function assessment used in the study confirmed that the spatial frequency at 10% contrast was much lower than the theoretical resolution computed from the pixel size.

Clinical outcome in periradicular surgery: effect of patient- and tooth-related factors--a multicenter study.

OBJECTIVE: To evaluate the effect of patient- and tooth-related factors on the outcome of apical surgery in a multicenter study. METHOD AND MATERIALS: A total of 281 teeth in 255 patients undergoing periradicular surgery were investigated clinically and radiographically 6 to 12 months postoperatively. RESULTS: The overall success rate was 88.0%. Sex was a significant (P = .024) predictor, with a success rate of 89.8% in females and 84.0% in males. The success rate was significantly higher in patients 31 to 40 years of age. The treatment of premolars resulted in a significantly higher success rate (91.9%) than the treatment of anterior teeth (86.1%, P = .042) and molars (86.4 %, P = .026). The loss of the buccal bone plate and the extension of apical osteolysis to the furcation area in molars resulted in a considerably lower success rate. Lesion size, preoperative pain, tenderness to percussion, fistula, and resurgery were significant factors. CONCLUSION: There are several factors influencing the success rate of apical surgery that must be taken into account when considering apical surgery as a treatment alternative.

[Orthodontic treatment of patients medicated with bisphosphonates-a clinical case report].

INTRODUCTION: Bisphosphonates (BP) are an established medication, e.g., for the prevention/therapy of osteoporosis. The effects of the changed bone metabolism for orthodontic treatments are unknown. CASE REPORT: A 66-year-old woman underwent a total oral rehabilitation. The therapy included (1) tooth extractions, (2) periodontal treatment, (3) insertion of dental implants, (4) provisional implant restorations, (5) orthodontic treatment, and (6) definite implant restorations. The orthodontic tooth movements were in- and retrusion of the upper frontal teeth, intrusion of the lower front teeth, using the dental implants as skeletal anchorage. After implant insertion and one month before beginning the orthodontic treatment, osteoporosis was diagnosed in this patient and, without notification to our facility, BP treatment was initiated by her general practitioner (alendronate oral, 70 mg/week), with an overall duration of intake of 7 months. After 13 months, the orthodontic treatment was successfully accomplished; however enlarged periodontal gaps, sclerotic bone areas, and mild apical root resorptions of the upper frontal teeth were found in this patient. CONCLUSION: Currently, there are no recommendations for orthodontic patients undergoing BP therapy. Orthodontic tooth movement in this low-risk patient with a short duration of intake and a low-dose BP medication was possible. Because of the reduced bone metabolism and the higher amount of side effects, the treatment should be performed with extremely light forces and frequent monitoring.

The influence of bone substitute materials on the bone volume after maxillary sinus augmentation: a microcomputerized tomography study.

OBJECTIVES: This study aims to evaluate the effect of adding bone substitute materials (BSM) to particulated autogenous bone (PAB) on the volume fraction (Vf) of newly formed bone after maxillary sinus augmentation. MATERIALS AND METHODS: Thirty healthy patients undergoing maxillary sinus augmentation were included. PAB (N = 10), mixtures of PAB and beta-tricalciumphosphate (PAB/ß-TCP) (N = 10), as well as PAB and ß-TCP and hydroxyapatite (PAB/HA/ß-TCP) (N = 10) were randomly used for sinus augmentation. A sample of the graft material was maintained from each patient at time of maxillary sinus augmentation, and Vfs of the PAB and/or BSM in the samples were determined by means of microcomputerized tomography (µ-CT). Five months later, samples of the grafted areas were harvested during implantation using a trephine bur. µ-CT analysis of these samples was performed, and the Vf of bone and BSM were compared with the data obtained 5 months earlier from the original material. RESULTS: The mean Vf of the bone showed a statistically significant increase (p < 0.05) in all groups after a healing period of 5 months without statistically significant difference between the groups. CONCLUSIONS: With regard to the increase of bone volume, it is not relevant if PAB is used alone or combined with ß-TCP or HA/ß-TCP. CLINICAL RELEVANCE: The amount of PAB and associated donor site morbidity may be reduced by adding BSM for maxillary sinus augmentation.

The influence of substitute materials on bone density after maxillary sinus augmentation: a microcomputed tomography study.

PURPOSE: To evaluate whether adding bone substitute materials to autogenous particulated bone (PAB) might have an effect on the density of the grafted bone after maxillary sinus augmentation. MATERIALS AND METHODS: Thirty healthy patients undergoing lateral antrostomy were included. Sinuses were augmented at random with PAB (n=10) (control group); a mixture of PAB and beta-tricalcium phosphate (Β-TCP) (n=10) (experimental group); or a mixture of PAB, Β-TCP, and hydroxyapatite (HA) (n=10) (experimental group). A sample of each graft material was obtained at time of maxillary sinus augmentation, and microcomputed tomography (Μ-CT) analyses were performed. Five months later, samples of the augmented areas (n=23) were harvested by means of a trephine bur, and Μ-CT analyses of these samples were performed. Density values for the bone were compared to the data obtained 5 months before from the original material. RESULTS: All groups showed increasing density values after a healing time of 5 months. Because of a high dropout rate, the sample size was too small to compare the groups statistically. CONCLUSIONS: Bone density increased after maxillary sinus augmentation for both PAB alone or in combination with substitute materials based on HA and/or Β-TCP particles. A larger sample size and a split-mouth design would help to reliably reveal significant differences between the single materials.

Counting touching cell nuclei using fast ellipse detection to assess in vitro cell characteristics: a feasibility study.

In this article, we describe a new image analysis software that allows rapid segmentation and separation of fluorescently stained cell nuclei using a fast ellipse detection algorithm. Detection time ranged between 1.84 and 3.14 s. Segmentation results were compared with manual evaluation. The achieved over-segmentation rate was 0.11 (0.1 double counts and 0.01 false positive detections), and the under-segmentation rate was of 0.03 over all images. We demonstrate the applicability of the proposed algorithm to automated counting of fluorescent-labeled cell nuclei and to tissue characterization. Moreover, the performance of the proposed algorithm is compared with preexisting automated image analysis techniques described by others.

Antibiotic susceptibility of cocultures in polymicrobial infections such as peri-implantitis or periodontitis: an in vitro model.

BACKGROUND: Although polymicrobial infections, such as peri-implantitis or periodontitis, were postulated in the literature to be caused by synergistic effects of bacteria, these effects remain unclear looking at antibiotic susceptibility. The aim of this study is to compare the antibiotic susceptibilities of pure cultures and definite cocultures. METHODS: Laboratory strains of Aggregatibacter actinomycetemcomitans (Aa) (previously Actinobacillus actinomycetemcomitans), Capnocytophaga ochracea (Co), and Parvimonas micra (Pm) (previously Peptostreptococcus micros) were cultivated under anaerobic conditions, and their susceptibilities to 10 antibiotics (benzylpenicillin G, ampicillin, amoxicillin, ampicillin/sulbactam, amoxicillin/clavulanic acid, minocycline, metronidazole, linezolid, azithromycin, and moxifloxacin) were tested using the Epsilometertest. Cocultures, each consisting of two or three bacteria, were treated analogously. RESULTS: All four cocultures showed lower susceptibilities to azithromycin and minocycline than to pure cultures. The coculture Aa-Co showed a lower susceptibility to moxifloxacin as did the coculture Aa-Pm to benzylpenicillin G; the coculture Co-Pm showed a lower susceptibility to amoxicillin, amoxicillin/clavulanic acid, metronidazole, and benzylpenicillin G. However, the coculture Co-Pm showed a higher susceptibility to ampicillin, linezolid and moxifloxacin as did Aa-Pm and Aa-Co-Pm to linezolid. CONCLUSIONS: In addition to established in vitro assays, it was demonstrated that antimicrobial cocultures caused antibiotic susceptibilities that differed from those of pure cultures. Bacterial cocultures frequently showed lowered susceptibilities to antibiotics.

Recognition of root canal orifices at a distance - a preliminary study of teledentistry.

The remote recognition of root canal orifices was tested on 50 images of endodontically accessed teeth acquired with an intra-oral camera. The images were stored on a laptop computer and were presented to 20 observers who marked the visible canal orifices using software which stored the canal locations in standard files. The marked positions were verified on histological slices. In 87% of the cases, the canal locations were marked correctly. Inter-observer reliability depended on the location of the reviewed root canal (kappa = 0.44-0.77). The detection rate was related to the professional experience of the observers. The maximum proportion of accurate detections was found for the observers with more than 10 years of professional experience. The minimum proportion of accurate detections, 79%, was by the observer with one year of experience. The results of the study suggest that remote recognition of root canals by experienced dentists can help younger colleagues in the detection of root canal orifices.

Ink-jet printout of radiographs on transparent film and glossy paper versus monitor display: an ROC analysis.

The aim of this study was to compare the depiction ability of small grayscale contrasts in ink-jet printouts of digital radiographs on different print media with CRT monitor. A CCD-based digital cephalometric image of a stepless aluminum wedge containing 50 bur holes of different depth was cut into 100 isometric images. Each image was printed on glossy paper and on transparent film by means of a high-resolution desktop inkjet printer at specific settings. The printed images were viewed under standardized conditions, and the perceptibility of the bur holes was evaluated and compared to the perceptibility on a 17-in CRT monitor. Thirty observers stated their blinded decision on a five-point confidence scale. Areas (Az) under receiver operating characteristics curves were calculated and compared using the pair wise sign tests. Overall agreement was estimated using Cohen's kappa device and observer bias using McNemar's test. Glossy paper prints and monitor display revealed significantly higher (P < 0.001) average Az values (0.83) compared to prints on transparent film (0.79), which was caused by higher sensitivity. Specificity was similar for all modalities. The sensitivity was dependent on the mean gray scale values for the transparent film.

Spatial relation between a rigid (digital) intraoral X-ray receptor and longitudinal axes of maxillary teeth.

The purpose of this study was to quantify the existing (inevitable) angle which in intraoral radiology appears between tooth length axis and receptor caused by the anatomical situation. Especially in the upper jaw, due to its arched anatomy, a true "paralleling technique" is not achievable. The angulation necessarily causes distortion and a foreshortening of the image; hence, the foreshortened image leads to misinterpretations in diagnostics. We investigated the effects of the realistic angulation on these image deteriorating factors. Two hundred ninety-four plaster models of the upper jaw were collected, and the angles between a dummy receptor and the axes of the central incisor or the first molar were measured. For evaluation, a rigid dummy of an intraoral charge-coupled device (CCD) receptor (30 mm × 40 mm) was used. The mean angulation evaluated for central incisors was 36.7° (range 19-56°) and for first molars 42.5° (range 26-56°). This leads to a foreshortening of the tooth ranging from 5.4% to 44.1% in the image, when magnification is neglected. Large angles of up to 56°, in both incisor and molar region, result in a relevant underestimation of true tooth length up to 44%. It is important to note that this error cannot be simply corrected by means of local magnification correction. Techniques should be developed that allow for automated assessment of the effective angle to provide information for distortion correction.

On cone-beam computed tomography artifacts induced by titanium implants.

OBJECTIVES: To briefly review the mathematical background of beam-hardening artifacts in cone-beam computed tomography (CBCT)-reconstruction and to investigate geometrical properties relevant for these reconstruction errors. By means of simulated and experimental results, beam-hardening effects caused by titanium implants are evaluated. MATERIALS AND METHODS: The geometrical and physical properties of the acquisition process of the projections used for 3D reconstruction are investigated and their effects on the CBCT images in the presence of titanium implants are derived. Beam-hardening effects are computed for a simplified polychromatic situation (three energy subsets of 80 and 110 kV) and compared with experimental results from a hard-plaster phantom containing two 'implants' (pure titanium rods; 4 mm diameter) exposed in two CBCT machines. RESULTS: Massive absorption within a typical implant body (diameter: 4 mm) was computed for the low-energy subset of both energies (80 kV: 99.7%; 110 kV: 90.9%), whereas the high-energy subsets are only marginally absorbed (80 kV: 14.8%; 110 kV: 11.3%). Accordingly, phantom data revealed drastically reduced gray values in artifact-affected regions (3DAccuitomo: -46% to -51%) or (3DExam: -55%) plus increased noise (+67% vs. +73%), when compared with unaffected regions. CONCLUSIONS: Our theoretical and experimental results prove massive beam-hardening artifacts for a typical implant diameter and typical energies of up-to-date CBCT machines. Meaningful artifact reduction has to be based on more sophisticated mathematical modeling of the actual physical image acquisition process rather than on postprocessing of the erroneous results obtained from the rather crude reconstruction algorithms used presently.

Implementation of new software for fast screening of cell compatibility on surface modifications using low-contrast time-lapsed microscopy.

Assessment of cell adhesion and cell size provides valuable information on surface biocompatibility. However, most investigations on cell morphology dynamics are time and resource consuming, of rather descriptive character and lack procedures for appropriate quantification. The aim of the study was to develop a software programme which allows automated cell segmentation and identification as well as calculation and further processing of cell size in low-contrast images. The software utilises modified edge detection and morphologic operations for automatic cell analysis in light microscopy images. In an application study, osteogenic cell-adhesion dynamics were quantified for the ECM proteins collagen type I (COL) and fibronectin (FIB) over a period of 12 hrs. Untreated tissue culture polystyrene (TCPS) served as control. The software programme proofed full function in automatic cell tracking and quantification of cell size. After 11 h, cell sizes were highest for COL (6391 ± 1167 µm(2)) and FIB (6036 ± 411 µm(2)) compared with TCPS (3261 ± 693 µm(2)). The developed software allows quantification of initial cell size changes on translucent surface modifications and is suitable as a reliable tool for fast biocompatibility screening. Osteogenic cell adhesion was significantly promoted by COL and FIB indicating the potential of respective functionalized biomaterial surfaces.

The treatment of anterior dental trauma.

BACKGROUND: Avulsed frontal teeth often cannot be saved because of improper or lack of initial treatment. The result is a need for multiple interventions over the patient's lifetime, which also carry a high financial cost. METHODS: We explored the subject of lost anterior teeth in young patients with a PubMed search based on the term "prevalence of traumatic dental injuries" over the time period 2000-2010. In this article, we selectively review the publications retrieved by the search and give case examples to illustrate the proper initial treatment of children and adolescents (ages 6 to 17) with broken anterior teeth. RESULTS: The search retrieved 138 articles. Here, we review retrospective clinical studies of dental trauma between the ages of 6 and 17: only 6 adequately designed studies of this type were found. The estimated prevalence of anterior dental trauma in this age group ranged from 6.4% to 37.9%. The recommended initial steps for the preservation of traumatized teeth are easy to take. Avulsed teeth can and should be replanted at once. If there is no time, or if the patient simultaneously has other, life-threatening injuries, the avulsed teeth can be stored in a special nutrient medium until they can be replanted. Commercially available tooth rescue boxes enable replantation to be performed up to 24 hours after the injury. CONCLUSION: The authors of the selected studies agree that dental trauma is often improperly treated. Timely treatment of injured anterior teeth prevents much further damage and expensive treatment for the affected young patients.

Ex vivo radiographic tooth length measurements with the reference sphere method (RSM).

A reference-based radiographic "reference sphere method" (RSM) for accurate length measurements in (dental) projection radiographs for the assessment of tooth length in dry human mandible sections is evaluated. RSM determines the depth coordinates of reference spheres placed in the object plane from the elliptical distortion of their shadows. Two segments (one canine and one molar) of dry human mandibles were exposed 95 times at different angulations (0-40°) on a dental charge-coupled device receptor. Three steel spheres (diameters d (1) = 2.00 mm, d (2) = 3.00 mm) were attached roughly coplanar with the tooth's main axis. Radiographs were assessed once by visual inspection plus manual landmark identification with a mouse-driven cursor. The results were compared to the true tooth length assessed after extraction and to a conventional method (C), i.e., the rule of proportion based on magnification of the sphere shadows. Mean relative length error was 2.28% (d (1)) and 0.46% (d (2)) for RSM and -13.58% (d (1)) and -9.90% (d (2)) for C. For both methods, length errors were significantly (p < 0.0001) correlated with the inclination relative to the receptor. RSM allows for complete a posteriori determination of the imaging geometry under the assumption of a known source-to-receptor distance. One specific application is foreshortening correction of objects coplanar with the reference spheres. Remaining errors are mainly due to incorrect landmark definition. In our setup, these were exaggerated by the visual/manual image-evaluation process. Automated image analysis has been shown for similar tasks to minimize these errors considerably.

Clinical evaluation of a modified marginal sulcular incision technique in endodontic surgery.

The authors evaluated periodontal parameters following apical surgery using a new marginal sulcular incision. In 65 cases, surgical access was achieved by means of a sulcular incision technique without the involvement of the adjacent periodontia and the interproximal papillae and in 33 cases by means of a submarginal trapezoidal technique. Periodontal parameters (probing pocket depth, gingival recession, clinical attachment loss, and tooth mobility [periotest]) were recorded at baseline and after 6 months. Scar formation and the loss of papilla height were evaluated photographically. No significant changes in the attachment level and no loss of papilla height were found in either group. A slight gingival recession (0.2 +/- 0.4 mm) corresponding to the decrease in pocket depths occurred on the buccal aspect with the sulcular incision. Tooth mobility was significantly increased in both groups immediately and 6 months after surgery. Scar formation was more unfavorable with the submarginal incision.

Comparison of five parameters as risk factors for peri-mucositis.

PURPOSE: The aim of this study was to identify risk factors for the development of clinical signs of peri-implant mucositis and for the presence of periodontal pathogens and to determine a possible correlation between these clinical signs and the presence of periodontal pathogens. MATERIALS AND METHODS: In 100 patients, a modified Plaque Index (PI), a modified Sulcular Bleeding Index (BOP), and pocket probing depth (PPD) were recorded. Patients with one implant site that scored positive for PI, BOP, and PPD greater than or equal to 5 mm were considered to have peri-implant mucositis. A sample taken at the implant with the deepest pocket was analyzed for periodontal pathogens. Implant surface roughness, smoking, augmentation at the implant site, type of dentition, and radiation therapy were recorded as possible cofactors in the disease process. RESULTS: Thirty-one patients showed clinical signs of peri-implant mucositis and, in 25 implant sites, periodontal pathogens were found. Smoking showed a statistically significant correlation with clinical signs of peri-implant mucositis (univariate analysis). For periodontal pathogens at the implant site, the type of dentition was statistically significant. In the multivariate analysis of the clinical signs of peri-implant mucositis, smoking and radiation therapy were significant explanatory variables. Seventy-two percent of the patients showed agreement for finding either clinical signs of peri-implant mucositis and periodontal pathogens or for no clinical signs and no pathogens. The sensitivity for diagnosis of peri-implant mucositis was 45%, and the specificity was 84%. CONCLUSIONS: Smoking was the most important risk factor in the formation of peri-implant mucositis. Radiation therapy was an explanatory variable for the occurrence of inflammation. Implant surface roughness, augmentation at the implant site, and type of dentition had little influence on clinical signs of peri-implant mucositis. The type of dentition influences the periodontal microbiota at the implant site.

Fast algorithm for detection of reference spheres in digital panoramic radiography.

In this paper, an algorithm for detection of reference spheres from digital panoramic radiographic images is presented. The proposed algorithm was tested on a database of 107 digital panoramic radiographic images which were used for dental diagnostics. Results show that the proposed method exhibits for detection of reference spheres, a sensitivity of 97.33% and specificity of 93.85%. Performance time differed between 0.55 and 2.36s depending on image size. The aim of this work was to provide a fast ellipse detection algorithm to reduce measuring time on preoperative implant planning by lowering the computational cost.

Incidence and predictive factors for perforation of the maxillary antrum in operations to remove upper wisdom teeth: prospective multicentre study.

BACKGROUND: Our aim was to evaluate the incidence of perforations of the sinuses and their related treatment after the removal of upper wisdom teeth depending on various anatomical and clinical variables. MATERIAL AND METHODS: A total of 1057 upper wisdom teeth were removed under local anaesthetic in the departments of oral surgery at the Universities of Bonn, Düsseldorf, Frankfurt and Mainz, Germany. Data were collected with the help of an anonymised questionnaire dealing with information about the patients, and the position and stage of the development of teeth, as well as the occurrence and size of an oro-antral communication and its treatment. RESULTS: Of 465 extractions and 592 osteotomies of the upper third molars, 134 interventions (13%) were related directly to the diagnosis of a perforated maxillary sinus. Acute oro-antral communication occurred as a result of the removal of completely impacted teeth in 88 of 370, (24%) by removal of partially impacted teeth in 23 of 222 (10%) and in fully erupted third molars in 23 of 465 (5%) of all cases. These differences are significant (p<0.001). In 111 (83%), the diameter of the oro-antral perforation was less than 3mm. In 25 (19%) of all sinus openings, a buccal sliding flap was used to close the extraction wound. We conclude that intraoperative fracture of the root, higher degree of impaction and higher age of the patient are associated with a greater likelihood of oro-antral perforation.