Objectives
Working Group 2 was convened to address topics relevant to prosthodontics and dental implants. Systematic reviews were developed according to focused questions addressing (a) the number of ...implants required to support fixed full‐arch restorations, (b) the influence of intentionally tilted implants compared to axial positioned implants when supporting fixed dental prostheses (FDPs), (c) implant placement and loading protocols, (d) zirconia dental implants, (e) zirconia and metal ceramic implant supported single crowns and (f) zirconia and metal ceramic implant supported FDPs.
Materials and methods
Group 2 considered and discussed information gathered in six systematic reviews. Group participants discussed statements developed by the authors and developed consensus. The group developed and found consensus for clinical recommendations based on both the statements and the experience of the group. The consensus statements and clinical recommendations were presented to the plenary (gathering of all conference attendees) and discussed. Final versions were developed after consensus was reached.
Results
A total of 27 consensus statements were developed from the systematic reviews. Additionally, the group developed 24 clinical recommendations based on the combined expertise of the participants and the developed consensus statements.
Conclusions
The literature supports the use of various implant numbers to support full‐arch fixed prostheses. The use of intentionally tilted dental implants is indicated when appropriate conditions exist. Implant placement and loading protocols should be considered together when planning and treating patients. One‐piece zirconia dental implants can be recommended when appropriate clinical conditions exist although two‐piece zirconia implants should be used with caution as a result of insufficient data. Clinical performance of zirconia and metal ceramic single implant supported crowns is similar and each demonstrates significant, though different, complications. Zirconia ceramic FDPs are less reliable than metal ceramic. Implant supported monolithic zirconia prostheses may be a future option with more supporting evidence.
The aim of this study was to evaluate the influence of different backgrounds on spectrophotometric colour values of natural teeth. Twenty volunteers (10 males and 10 females) with a mean age of ...25 years and 9 months (±3 years and 2 months) were each subjected to 4 spectrophotometric measurements of their upper right central incisor. Each sample was measured with alternatively black, 50 % grey, white or no background (positive control). Δ
E
medians ranged from 0.9 to 5.9. All artificial backgrounds presented significant differences (
p
< 0.05) when compared to values obtained without any background. No significant differences were observed between black and 50 % grey background (
p
> 0.05). If an artificial background needs to be used, as for example when performing in vitro studies, preference should be given to a black background as it approaches best the clinical situation (i.e. no background). Even if no statistically significant differences were found when compared with the grey background, the black background should be preferred due to its lower Δ
E
medians, standard deviation as well as lower minimum and maximum values.
The purpose of the study was to determine whether the hinge axis registration and the transfer modality (facebow transfer vs. average mounting) from the subject to the articulator affect the ...three-dimensional condylar shift between the centric relation (CR) and the maximum intercuspation (MI) position.
The study was comprised of 32 fully dentate subjects (16 male and 16 female). Only the asymptomatic participants with normal occlusal relations (Angle class I) aged 20 - 33 (mean age 22.6 ± 4.7) met the inclusion criteria. Three-dimensional condylar shift (anteroposterior, superoinferior and mediolateral shift) between the centric relation position (CR) and the maximum intercuspation (MI) position was analyzed by means of Mandibular Position Indicator (SAM Prazisionstechnik GmbH, Muenchen, Germany).
The average three-dimensional condylar shift was 0.13 ± 0.12 mm for facebow transfer and 0.22 ± 0.23 mm for average mounting. There were no statistically significant differences noted between genders. The results of the Mann-Whitney test showed statistically significant differences for anteroposterior and superoinferior condylar shift (P < 0.001). However, the difference in the mediolateral shift was not statistically significant.
In order to find discrepancies within the three-dimensional condylar shift, facebow transfer proved to be more accurate than the average mounting in the semi-adjustable articulator. However, the average value of three-dimensional shifts of the condyle did not differ from normal values and they did not have clinical significance. Thus, both ways of transfer modalities (facebow transfer and average mounting) in asymptomatic subjects with normal occlusion can be considered reliable.
This study investigated the relationship between chronic head, face and neck pain, and the level of depression in Croatian war veterans with post-traumatic stress disorder (PTSD). The presence of ...self-reported pain, pain on digital palpation, and pain severity in masticatory and neck muscles, temporomandibular joints and sinuses, as well as the level of depression were assessed in a group of war veterans with PTSD (n=52). Control groups consisted of war veterans without PTSD (n=50) and healthy men that were not engaged in war actions and were free from PTSD (n=50). The number of self-reported pain and number of painful sites were correlated with the level of depression. More self-reported pain and painful sites were recorded in the group of war veterans with PTSD as compared with either war veterans without PTSD or healthy men. Furthermore, PTSD patients mostly suffered from severe depression. There was a statistically significant positive correlation between all investigated pain parameters and level of depression. As the most important finding, the present study demonstrated chronic head, face and neck pain to be related to depression in PTSD patients.
The purpose of this retrospective radiographic study was to analyze the thickness of the facial bone wall at teeth in the anterior maxilla based on cone beam computed tomography (CBCT) images, since ...this anatomical structure is important for the selection of an appropriate treatment approach in patients undergoing postextraction implant placement. A total of 125 CBCT scans met the inclusion criteria, resulting in a sample size of 498 teeth. The thickness of the facial bone wall in the respective sagittal scans was measured perpendicular to the long axis of the tooth at two locations: at the crest level (4 mm apical to the cementoenamel junction; MP1) and at the middle of the root (MP2). No existing bone wall was found in 25.7% of all teeth at MP1 and in 10.0% at MP2. The majority of the examined teeth exhibited a thin facial bone wall (< 1 mm; 62.9% at MP1, 80.1% at MP2). A thick bone wall (⋝ 1 mm) was found in only 11.4% of all examined teeth at MP1 and 9.8% at MP2. There was a statistically significant decrease in facial bone wall thickness from the first premolars to the central incisors. The facial bone wall in the crestal area of teeth in the anterior maxilla was either missing or thin in roughly 90.0% of patients. Both a missing and thin facial wall require simultaneous contour augmentation at implant placement because of the well-documented bone resorption that occurs at a thin facial bone wall following tooth extraction. Consequently, radiographic analysis of the facial bone wall using CBCT prior to extraction is recommended for selection of the appropriate treatment approach.
To evaluate the color stability of composite resin types designed for esthetic anterior restorations when continuously exposed to various staining agents.
Thirty-six disk-shaped specimens were made ...of each of 12 composite materials (1 microfilled and 11 hybrid composites). After dry storage at 37 degrees C for 24 hours in an incubator (INP-500, Memmert), the initial color of each specimen was assessed by a calibrated reflectance spectrophotometer (SpectroShade). Specimens were immersed in five staining solutions or dry stored (control). All specimens were kept in an incubator at 37 degrees C for 99 days. Test solutions were changed every 14th day to avoid bacteria or yeast contamination. After 99 days of storage, spectrophotometric measurements were again performed and L*a*b* scores once more recorded to determine the color changes.
Wine proved to have the highest staining potential followed by coffee, tea, orange juice, and cola, which had the lowest staining potential. The highest color change measured against a white background was observed for Durafill (Heraeus Kulzer) in wine (DeltaE = 62.3), while the least staining was found for Enamel HFO (Micerium) in cola (DeltaE = 3.5). The highest color change measured against a black background was observed for EsthetX (Dentsply) in wine (DeltaE = 46.0), while the least staining was observed for Enamel HFO in cola (DeltaE = 2.5).
Composite staining susceptibility proved to vary among composite structure and brands. Potential discoloration might be limited by dietary restriction based on such in vitro evaluation.
This retrospective radiographic study analyzed the dimensions of the alveolar bone in the posterior dentate mandible based on cone beam computed tomography (CBCT) images. A total of 56 CBCT images ...met the inclusion criteria, resulting in a sample size of 122 cross sections showing posterior mandibular teeth (premolars and molars). The thickness of the buccal and lingual bone walls was measured at two locations: 4 mm apical to the cementoenamel junction (measurement point 1, MP1) and at the middle of the root (measurement point 2, MP2). Further, alveolar bone width was assessed at the level of the most coronal buccal bone detectable (alveolar bone width 1, BW1) and at the superior border of the mandibular canal (alveolar bone width 2, BW2). The vertical distance between the two as well as the presence of a lingual undercut were also analyzed. There was a steady increase in buccal bone wall thickness from the first premolar to the second molar at both MP1 and MP2. BW1 at the level of the premolars was significantly thinner than that for molars. Alveolar bone height was constant for all teeth examined. For the selection of an appropriate postextraction treatment approach, analysis of the alveolar bone dimensions at the tooth to be extracted by means of CBCT can offer valuable information concerning bone volume and morphology at the future implant site.
A precise radiographic evaluation of the local bone dimensions and morphology is important for preoperative planning of implant placement. The purpose of this retrospective study was to analyze ...dimensions and morphology of edentulous sites in the posterior mandible using cone beam computed tomography (CBCT) images. This retrospective radiographic study measured the bone width (BW) of the mandible at three locations on CBCT scans for premolars (PM1, PM2) and molars (M1, M2): at 1 mm and 4 mm below the most cranial point of the alveolar crest (BW1, BW2) and at the superior border of the mandibular canal (BW3). Furthermore, the height (H) of the alveolar process (distance between the measuring points BW1 and BW3), as well as the presence of lingual undercuts, were analyzed. A total of 56 CBCTs met the inclusion criteria, resulting in a sample size of 127 cross sections. There was a statistically significant increase from PM1 to M2 for the BW2 (P < .001), which was not present for BW1 and BW3 values. For the height of the alveolar process, the values exhibited a decrease from PM1 to M2 sites. Sex was a statistically significant parameter for H (P = .001) and for BW1 (P = .03). Age was not a statistically significant parameter for bone width (BW1: P = .37; BW2: P = .31; BW3: P = .51) or for the height of the alveolar process (P = .41) in the posterior mandible. Overall, 73 (57.5%) edentulous sites were evaluated to be without visible lingual undercuts; 13 (10.2%) sites exhibited lingual undercuts classified as influential for implant placement. Precise evaluation of the alveolar crest by cross-sectional imaging is of great value to analyze vertical and buccolingual bone dimensions in different locations in the posterior mandible. In addition, CBCTs are valuable to diagnosing the presence of and potential problems caused by lingual undercuts prior to implant placement.
To examine whether psychological variables such as depression and non-specific physical symptoms (somatization) influence pain entity among acute and chronic TMD patients with one or more TMD ...diagnoses (muscle disorders, MD; disc displacements, DD; and arthralgia, arthritis, arthrosis, AAA). One hundred and fifty-four patients (37 male and 117 female; mean age, 39.0 +/- 14.5 years) with Research Diagnostic Criteria for Temporomandibular Disorders (RDC/ TMD) protocol were selected. Differences in mean depression and somatization scores between acute and chronic TMD patients, as well as TMD patients with one or multiple TMD diagnoses were compared by using the parametric T-test for independent samples. The majority of patients were acute TMD patients (81.8%), while the remaining 28 patients (18.2%) were chronic TMD patients. 62% of patients had only one TMD diagnosis (MD or DD or AAA), 31% of patients had two diagnoses (MD+DD, MD+AAA, DD+AAA) and, finally, 7% of patients had three diagnoses (MD+DD+AAA) according to the RDC/TMD protocol. According to the SCL-90 psychometric evaluation, 19.5% of patients presented a severe depression score (> 1.105), 27.3% of participants presented a severe somatization score with pain items included (> 1.000). The results of the t-test for independent samples showed statistically significant differences between acute and chronic TMD patients (p < 0.001), as well as between patients who were assigned one diagnosis (p = 0.019) and patients who had two or more diagnoses (p < 0.001); for mean levels of depression and somatization scores. Chronic TMD patients and patients with multiple TMD diagnoses had higher rates of depression and somatization in this study. These results could be used in a tailored strategy of TMD treatment.
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