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1.
Nawakamon Suriyan Lertrit Sarinnaphakorn George R. Deeb Sompop Bencharit 《The Journal of prosthetic dentistry》2019,121(3):411-416
Statement of problem
Conventional guided implant surgery promises clinical success through implant placement accuracy; however, it requires multiple drills along with surgical sleeves and sleeve adapters for the horizontal and vertical control of osteotomy drills. This results in cumbersome surgery, problems with patients having limited mouth opening, and restriction to specific drill or implant manufacturers. A protocol for using trephination drills to simplify guided surgery and accommodate multiple implant systems is introduced.Purpose
The purpose of this clinical study was to evaluate the accuracy of implant placement using this novel guided trephine drill protocol with and without a surgical sleeve.Material and methods
Intraoral scanning and preoperative cone beam computed tomography (CBCT) scans were used for implant treatment planning. Surgical guides were fabricated using stereolithography. Implant surgery was performed using the guided trephination protocol with and without a surgical sleeve. Postoperative CBCT scans were used to measure the implant placement deviations rather than the implant planning position. Surgical placement time and patient satisfaction were also documented. One-tailed t test and F-test (P=.01) were used to determine statistical significance.Results
Thirty-five implants in 17 participants were included in this study. With a surgical sleeve, implant positional deviations were 0.51 ±0.13 mm vertically, 0.32 ±0.10 mm facially, 0.11 ±0.11 mm lingually, and 0.38 ±0.13 mm mesially. Without a surgical sleeve, implant positional deviations were 0.58 ±0.27 mm vertically, 0.3 ±0.14 mm facially, 0.39 ±0.16 mm lingually, and 0.41 ±0.12 mm mesially. No statistically significant difference was found between the 2 protocols (P>.01), except that the sleeve group had greater vertical control precision (F-test, P=.006), reduced placement time, and the time variation was reduced (t test, P=.003; F-test, P<.001).Conclusions
This trephination-based, guided implant surgery protocol produces accurate surgical guides that permit guided surgery in limited vertical access and with the same guided surgery protocol for multiple implant systems. Guided sleeves, although not always necessary, improve depth control and reduce surgical time in implant placement. 相似文献2.
Yiqin Fang Xueyin An Seung-Mi Jeong Byung-Ho Choi 《The Journal of prosthetic dentistry》2019,121(5):836-842
Statement of problem
Implant placement in the anterior regions is often challenging because of limited space and bone volume availability.Purpose
The purpose of this clinical study was to investigate the accuracy of computer-guided surgery with a long drill key to place implants in the anterior regions.Material and methods
Computer-guided implant surgery was performed for 32 participants requiring implants in anterior regions. The procedure involved using a 12-mm-long drill key to guide the 2.0-mm-diameter drill. Deviations between the planned and actual implant positions were evaluated by using cone beam computed tomography (CBCT) scans obtained before and after surgery. A t test was used for comparisons between the planned and placed implants and to determine the influence of the arch (maxilla/mandible) and time (immediate/delayed) on accuracy.Results
A total of 40 implants (20 implants in the maxilla and 20 implants in the mandible) were placed. The mean linear deviation was 0.46 mm (range, 0 to 1.15 mm) for the implant shoulder and 0.67 mm (range, 0.14 to 1.19 mm) for the implant apex. The mean angular deviation was 1.40 degrees (range, 0.30 to 2.57 degrees). The mean depth deviation was 0.15 mm (range, 0.10 to 0.82 mm).Conclusions
This clinical study showed that the accuracy of computer-guided implant placement may be enhanced by using a long drill key and may thus enable more accurate implant placement in anterior regions. 相似文献3.
Andrea F. Campello Marília F. Marceliano-Alves José F. Siqueira Fábio V. Marques Fábio R. Guedes Ricardo T. Lopes Fabrícia O. Alvarenga Flávio R.F. Alves 《Journal of endodontics》2019,45(5):619-622
Introduction
This study evaluated the accuracy and reliability of the tactile perception of the first apical binding file (FABF) and cone-beam computed tomographic (CBCT) imaging in estimating the canal diameter at the working length (WL).Methods
Ten anterior mandible segments were obtained from cadavers maintained in formalin and scanned using CBCT and high-resolution micro–computed tomographic (micro-CT) imaging. Scans were used to measure the smallest canal diameter of 38 mandibular incisors at 1 mm short of the root apex. After coronal access preparation, the canals of these teeth were explored with a size 08 K-file up to the radiographic apex, and the WL was established 1 mm shorter. Larger K-files were passively introduced in the canal up to the WL until binding was felt and the next instrument size could not reach this point. This instrument was regarded as the FABF. The accuracy and level of agreement (reliability) of the FABF and CBCT imaging in determining the initial apical canal size were determined using the Pearson correlation coefficient and the intraclass correlation coefficient, respectively, considering the micro-CT measurements as the gold standard.Results
The Pearson correlation coefficient and the intraclass correlation coefficient were statistically significant when CBCT imaging was compared with micro-CT imaging (P < .01), showing a moderate accuracy (r = 0.61) and good reliability (0.74). On the other hand, FABF was inaccurate and unreliable (P > .05). The means of the smallest root canal diameter obtained by micro-CT and CBCT imaging were 0.22 mm (range, 0.14–0.34 mm) and 0.23 mm (range, 0.13–0.37 mm), respectively. The mean of the FABF diameter was 0.15 mm (range, 0.08–0.30 mm).Conclusions
Although FABF did not accurately reflect the diameter of the apical canal at the WL, CBCT imaging showed good accuracy and reliability. Data from CBCT imaging regarding the initial apical canal size may be used to plan root canal enlargement. 相似文献4.
Paul Weigl Georgia Trimpou Jonas Lorenz Georg-Hubertus Nentwig Hans-Christoph Lauer 《The Journal of prosthetic dentistry》2019,121(4):618-622
Statement of problem
Nonrigid retainer systems for removable implant superstructures are associated with negative effects such as rocking and increased load on the denture base. Rigid retainer systems such as telescopic crowns reduce these negative effects, but their fabrication demands highly skilled dental technicians and is therefore expensive. Whether a protocol with prefabricated retainers will reduce production time is unclear.Purpose
The purpose of this prospective clinical trial was to evaluate a prefabricated telescopic retainer and a treatment protocol including the intraoral luting of a framework.Material and methods
A total of 23 participants (15 women and 8 men with a mean age of 61.6 ±2.9 years) were included. After 3 dropouts, 21 removable dentures (9 mandibular and 12 maxillary) retained by 91 delayed loaded Ankylos implants were investigated. All implants were restored with prefabricated conically shaped abutments (SynCone-abutment). The prefabricated corresponding cone matrix was assembled intraorally into a metal frame with autopolymerizing resin. After a loading period of 3 years, a follow-up examination investigated the fit of the framework, the prosthetic aftercare, the technical failures, and the retention force. A questionnaire was used to evaluate participant satisfaction. In addition, laboratory fabrication time and costs were compared with those of individually fabricated restorations.Results
One mandibular implant was lost after 25 months (survival rate, 98.9%). The removable dentures showed no apparent rocking and minimal prosthetic maintenance during the 36-month trial. No dentures required relining. The retention force was scored as good in 17 participants and high (with 6 implants in the maxilla) and low (with 2 implants in the mandible) in 2 participants each. No technical failures occurred. An assessment of laboratory fabrication time and costs revealed reduced time and costs. Patient satisfaction was significantly increased (P<.001) over the entire observation time.Conclusions
The SynCone retainer presented a time- and cost-efficient treatment option with sufficient long-term retention for removable dentures and high patient satisfaction. Mandibular prostheses restored with 2 implants had limited success. 相似文献5.
Shanon Patel Risha Patel Federico Foschi Franceso Mannocci 《Journal of endodontics》2019,45(4):406-413
Introduction
The purpose of this study was firstly to compare the impact of radiographs, cone-beam computed tomographic (CBCT) imaging, and 3D Endo software (Dentsply Sirona, Ballaigues, Switzerland) on the assessment of root canal anatomy and radiographic quality of endodontic treatment and secondly to assess stress levels in the same cohort of residents performing endodontic treatment.Methods
Sixty patients requiring primary molar endodontic treatment were allocated randomly into 3 groups: group 1 (n = 20), conventional radiographs (periapical radiography [PR]) only; group 2 (n = 20), PR and CBCT imaging; and group 3 (n = 20), PR, CBCT imaging, and 3D Endo software. All treatment was performed using a standardized protocol. Residents completed a questionnaire to assess their stress levels and usefulness of the imaging modality used. The radiographic quality of completed cases was assessed by 2 experienced endodontists who were not involved in the supervision of the cases being assessed.Results
Groups 2 (CBCT imaging) and 3 (PR, CBCT imaging, and 3D Endo) proved significantly better than group 1 (PR) (P < .001) for assessing the number of root canals and anatomy and estimating the working lengths. Group 3 provided a significantly more accurate determination of the working level (P = .002). There were significantly more cases with obturation short of the apex (<2 mm) and voids in group 1 compared with group 3 (P < .05) and a significantly higher number of cases with voids in group 1 compared with group 3 (P < .01). Clinicians found treatment to be moderately or very stressful in 75%, 5%, and 0% in groups 1, 2, and 3, respectively.Conclusions
3D Endo software followed by CBCT imaging were found to be more desirable for the evaluation of root canal anatomy and working lengths and reducing the residents' stress levels. 相似文献6.
Eduarda Helena Leandro Nascimento Marcela Ramos Abrahão Elias Victor Hugo Fernandes Vasconcelos Francisco Haiter-Neto Elismauro Francisco Mendonça Thiago Oliveira Sousa 《Journal of endodontics》2019,45(5):549-553
Introduction
Imaging methods are essential for the correct identification of root canal anatomy, which is a key factor for successful endodontic therapy. This study aimed to evaluate the performance of periapical radiography (PR) and cone-beam computed tomographic (CBCT) imaging in identifying the apical delta (AD) using micro-computed tomographic imaging as the gold standard.Methods
PR and CBCT images of 110 human premolars (120 root canals) were obtained using the VistaScan digital intraoral system (Durr Dental, Beitigheim-Bissinger, Germany) and the 3D Accuitomo CBCT unit (J Morita, Kyoto, Japan), respectively. Two oral radiologists assessed the PR and CBCT images for the presence of ADs using a 5-point scale. Additionally, in the CBCT images, the number of apical foramina was also evaluated. The gold standard was established by means of micro–computed tomographic imaging. The diagnostic values related to PR and CBCT imaging were compared using the McNemar test. The detection of the number of foramina was compared using the paired t test (α ≤ 0.05).Results
ADs were present in 40 root canals (33.3%). Both PR and CBCT images differed significantly from the gold standard (P < .05) in the detection of ADs. CBCT imaging showed higher values than PR for all diagnostic tests (P < .05). Despite the moderate accuracy of PR (0.62) and CBCT imaging (0.73), these methods presented very low sensitivity values (0.07 and 0.35 for PR and CBCT, respectively). CBCT imaging had a tendency of underestimating the number of foramina (P < .05).Conclusions
CBCT imaging showed better performance than PR in the detection of ADs; both imaging modalities underestimate its presence when compared with the gold standard. In general, the number of apical foramina cannot be reliably assessed using CBCT imaging. 相似文献7.
Shira Ackerman Francisco Curiel Aguilera John M. Buie Gerald N. Glickman Mikhail Umorin Qian Wang Poorya Jalali 《Journal of endodontics》2019,45(5):615-618
Introduction
Cone-beam computed tomographic (CBCT)-based 3-dimensional–printed surgical guides, such as those used in implant placement and orofacial surgery, allow for accurate planning and performance of surgical procedures. The objective of this study was to evaluate the accuracy of CBCT-designed surgical guides for use during endodontic surgery.Methods
A split-mouth design was conducted using 48 roots in a cadaver model. In the experimental group, using information from the preoperative CBCT scans and digital impressions, surgical guides were designed using Blue Sky Bio (Grayslake, IL) planning software and printed using a Form 2 3-dimensional printer (Formlabs, Somerville, MA). The guides were designed to allow for surgical access at 3 mm from the apex of each root with depth control to the lingual or palatal surface of the root. In the control group, surgical access was completed “freehand” by visually approximating measurements from the CBCT scan only. The planned and postoperative CBCT images were superimposed, and the deviation of the surgical access point from the planned target was measured using Invivo software (Anatomage, San Jose, CA). A 2-tailed t test and the Fisher exact test were conducted to compare the deviation in the experimental CBCT-guided group versus the control CBCT-approximated freehand group.Results
The mean deviation for the guided group (1.743 mm) was significantly less than that of the approximated freehand group (2.638 mm, P < .001). Only in 11 of the 24 samples of the control group was surgical access considered clinically successful (within the apical area of the root), whereas all 24 of the experimental samples were considered clinically successful.Conclusions
Using a CBCT-designed printed surgical guide is a more accurate method for access to the apical portion of the root during surgical endodontics compared with a “freehand” CBCT-approximated method. 相似文献8.
Najla Chebib Nicole Kalberer Murali Srinivasan Sabrina Maniewicz Thomas Perneger Frauke Müller 《The Journal of prosthetic dentistry》2019,121(4):623-630
Statement of problem
Simplified edentulous jaw impression techniques have gained popularity, while their validity has not yet been evaluated.Purpose
The purpose of this clinical study was to compare the trueness of maxillary edentulous jaw impressions made with irreversible hydrocolloid (ALG), polyvinyl siloxane (PVS), PVS modified with zinc oxide eugenol (ZOE) (PVSM), and an intraoral scanner (TRI) with a conventionally border-molded ZOE impression (control).Material and methods
Twelve edentulous maxillary impressions were made with the impression techniques. The analog impressions were scanned using a laboratory scanner, imported into 3-dimensional comparison software, and superimposed against the corresponding control. Trueness was evaluated by calculating the effective deviation known as root mean square (RMS) for the entire surface (ES) and for specific regions of interest such as peripheral border, inner seal, midpalatal suture, ridge, and posterior palatal seal. The secondary outcomes for this study were the patients' perception of the impression techniques. Statistical analyses with the Wilcoxon tests were carried out (α=.05).Results
For ES, significant differences were found when comparing ALG (1.21 ±0.35 mm) with PVS (0.75 ±0.17 mm; P=.008), PVSM (0.75 ±0.19 mm; P=.012), and TRI (0.70 ±0.18 mm; P=.006) but not among the other groups. Significant differences were found for peripheral border when comparing ALG (2.03 ±0.55 mm) with PVS (1.12 ±0.32 mm; P=.006), PVSM (1.05 ±0.29 mm; P=.003), and TRI (1.38 ±0.25 mm; P=.008), as well as TRI and PVSM (P=.028). Significant differences were also found for inner seal when comparing ALG (0.74 ±0.36 mm) with PVSM (0.52 ±0.13 mm; P=.041), as well as TRI (0.8 ±0.25 mm) versus PVS (0.56 ±0.14 mm; P=.005) and PVSM (P=.005). The difference at the ridge was significant when comparing PVS (0.18 ±0.07 mm) with PVSM (0.28 ±0.19 mm; P=.015) but not among the other groups. A significant difference was also found for posterior palatal seal when comparing PVS (0.55 ±0.41 mm) with PVSM (0.60 ±0.43 mm; P=.034). Patient perceptions showed significantly better satisfaction scores for ALG (1.83 ±2.03) and PVS (3.17 ±2.40) than for TRI (4.08 ±2.71), PVSM (4.58 ±2.35), and ZOE (6.83 ±1.75).Conclusions
Edentulous impressions made with PVS, PVSM, and TRI had similar deviations and may yield clinically acceptable results. Irreversible hydrocolloids are contraindicated for definitive impression making in completely edentulous jaws. 相似文献9.
S.E.C.M. van de Vijfeijken R. Schreurs L. Dubois A.G. Becking 《Journal of cranio-maxillo-facial surgery》2019,47(4):542-547
Purpose
The aim of this study was to evaluate the accuracy of resection templates in cranioplasties in order to facilitate a one-stage resection and cranial reconstruction. Patients and methods: In three cases, cranial resections were combined with direct reconstructions using the principles of computer-aided design, manufacturing, and surgery. The precision of the resection template was evaluated through a distance map, comparing the planned and final result.Results
The mean absolute difference between the planned and actual reconstructed contour was less than 1.0 mm. After 3 years, no clinical signs of infection or rejection of the implants were present. The computed tomography scans showed no irregularities, and the aesthetic results remained satisfactory.Conclusion
One-stage resection and cranial reconstruction using a resection template, control template, and a prefabricated patient-specific implant of poly(ether-ether-ketone) (PEEK) proved to be a viable and safe method. 相似文献10.
Björn Gjelvold Deyar Jallal Hadi Mahmood Ann Wennerberg 《The Journal of prosthetic dentistry》2019,121(3):498-503
Statement of problem
Different factors influence the degree of deviation in dental implant position after computed tomography–guided surgery. The surgical guide–manufacturing process with desktop 3D printers is such a factor, but its accuracy has not been fully evaluated.Purpose
The purpose of this in vitro study was to evaluate the deviation in final dental implant position after the use of surgical guides fabricated from 2 different desktop 3D printers using a digital workflow.Material and methods
Twenty 3D-printed resin models were prepared with missing maxillary premolar. After preoperative planning, 10 surgical guides were produced with a stereolithography printer and 10 with a digital light-processing (DLP) printer. A guided surgery was performed; 20 dental implants (3.8×12 mm) were installed, and a digital scan of the dental implants was made. Deviations between the planned and final position of the dental implants were evaluated for both the groups.Results
A statistically significant difference between stereolithography and DLP were found for deviation at entry point (P=.023) and the vertical implant position (P=.009). Overall lower deviations were found for the guides from the DLP printer, with the exception of deviation in horizontal implant position.Conclusions
The tested desktop 3D printers were able to produce surgical guides with similar deviations with regard to the final dental implant position, but the DLP printer proved more accurate concerning deviations at entry point and vertical implant position. 相似文献11.
Lisa A. Lang Sarah E. Hansen Norma Olvera Sorin Teich 《The Journal of prosthetic dentistry》2019,121(4):611-617
Statement of problem
Identifying factors that affect the clinical outcomes of implant therapy is important.Purpose
The purpose of this retrospective study was to determine whether implant location was a factor affecting the complication and failure rates of single-tooth implant-supported restorations in a predoctoral setting.Material and methods
The charts of 431 patients treated with a surgically placed dental implant and restored with a single crown in the predoctoral clinic were analyzed. Data on implant location, type of complication (surgical or prosthetic), and type of failure were collected and analyzed according to implant location using the Fisher Exact Test and Mantel-Haenszel Exact Chi Square Test analysis (α=.05).Results
The charts revealed 158 complications (68 surgical and 90 prosthetic) in 110 patients, and 3.9% of the implants failed. No statistically significant difference was found between the number of surgical complications or prosthetic complications in the maxilla and the mandible (P=.469).Conclusions
Jaw location (maxilla compared with mandible) of the implant had no statistically significant impact on the incidence of surgically or prosthetically related complications. No statistically significant difference was found in overall implant failures, surgical failures, and prosthetic failures between maxillary and mandibular implants. 相似文献12.
Adrien Naveau Christophe Rignon-Bret Claudine Wulfman 《The Journal of prosthetic dentistry》2019,121(5):775-781.e1
Statement of problem
The success of single, anterior, implant-supported restorations relies on mechanical and esthetic outcomes. Titanium has been the most commonly used material for abutments, but zirconia is increasingly chosen for its appearance despite its unclear mechanical performance. Today, manufacturers market prefabricated, computer-aided design and computer-aided manufacturing (CAD-CAM) custom and zirconia abutments with titanium connections.Purpose
The purpose of this study was to systematically review the mechanical and esthetic outcomes of implant zirconia abutments used in the anterior region, considering the design changes of the past 5 years.Material and methods
An electronic search was conducted in Medline (PubMed) for studies on zirconia abutments. All clinical studies with at least a 1-year follow-up and case series (>5 abutments) published after 2013 were included. Mechanical and esthetic outcomes were collected.Results
Of the 231 retrieved studies, 20 remained for quantitative analysis. Twelve described mechanical outcomes, and 15 focused on esthetics, using mainly the pink esthetic score. Five articles reported abutment fractures and no chipping. No difference was found between prefabricated and custom abutments or internal and external implant connections regarding fractures or screw loosening. All authors reported “good to excellent” esthetic integration in terms of restorations and soft-tissue color and the presence and height of papillae. The most difficult esthetic parameters to achieve were root convexity, soft-tissue color, and texture and level of mucosa.Conclusions
Esthetics remain the major advantage of zirconia abutment when compared with titanium, despite reservations concerning the risk of mechanical complications. Data are lacking for zirconia abutments with titanium inserts, although the prospects for this design are promising. 相似文献13.
Alex Leo Sequeira Aparna I. Narayan Vinu Thomas George 《The Journal of prosthetic dentistry》2019,121(5):843-847
Statement of problem
Variation in the baseline mechanical properties of polyamide thermoplastic polymers used in the fabrication of prosthetic dental appliances and the effects of nonaldehyde disinfectants on the mechanical properties of these polymers are unclear.Purpose
The purpose of this in vitro study was to compare the flexural and impact strengths of 2 flexible denture materials (Valplast and Sunflex) and evaluate the effect of 24-hour immersion in nonaldehyde disinfectant (Perform) on their flexural and impact strengths.Material and methods
Of 48 specimens of Valplast and Sunflex, half were immersed in nonaldehyde disinfectant solution containing the active ingredient 2% peroxymonosulfate for 24 hours. Flexural and impact strengths were measured using a universal testing machine. The Student t test with Bonferroni correction was used (α=.008).Results
For the Valplast group, the mean ±standard deviation flexural strength was 27.8 ±0.57 MPa, and the impact strength was 3.5 ±0.98 kJ/m2. For the Sunflex group, the mean flexural strength was 57.4 ±4.09 MPa, and the impact strength was 6.0 ±3.11 kJ/m2. Sunflex showed greater flexural strength (P≤.001) and impact strength (P=.001) than Valplast. A significant increase in the impact strength (P≤.001) but not in the flexural strength of Valplast was observed after exposure to the disinfectant solution. Immersion disinfection had no significant effect on the strength of Sunflex.Conclusions
The flexural and impact strengths of Sunflex were significantly greater than those of Valplast. Immersion disinfection with peroxymonosulfate had no significant effect on Sunflex but increased the impact strength of Valplast. 相似文献14.
Ahmed Jamleh Amjad Alghaihab Abdulmohsen Alfadley Hussam Alfawaz Abdullah Alqedairi Khalid Alfouzan 《Journal of endodontics》2019,45(5):611-614
Introduction
The aim of this in vitro study was to compare the cyclic fatigue resistance and torsional resistance of EdgeTaper Platinum (ETP) with those of ProTaper Gold (PTG) at simulated body temperature.Methods
ETP and PTG files with #25 tip size were selected. Cyclic fatigue tests were performed in a stainless steel artificial canal until file fracture occurred. The time to fracture was recorded. For the torsional resistance testing, the apical 5 mm of the file was firmly secured with acrylic resin, and the assembly was fixed over torque gauge device. A uniform torsional stress was applied with continuous rotation motion until fracture occurred. The torque at failure was recorded. Both experiments were conducted at 35 ± 1°C. Fractured surfaces were tested via scanning electron microscopy. Statistical analysis was performed using independent Student t test at 5% significance level.Results
The ETP had superior cyclic fatigue resistance than PTG (P < .01). However, it exhibited lower torsional resistance (P < .05). The ETP and PTG showed typical features of cyclic and torsional fatigue behavior under scanning electron microscopy.Conclusions
The ETP exhibited superior resistance to cyclic fatigue but failed to show any improvement in the torsional resistance compared with PTG. 相似文献15.
Shajidan Kelimu Mariko Hattori Shataer Awuti Mahmoud E. Elbashti Yuka I. Sumita Hisashi Taniguchi 《The Journal of prosthetic dentistry》2019,121(4):671-675
Statement of problem
A palatogram aids prosthodontists and speech pathologists in evaluating the precise prosthetic treatment needed and the effectiveness of such treatment to improve speech intelligibility. Powder is commonly used to visualize tongue-palate contact, where wetted areas of powder in the oral cavity reveal such contact during palatography. However, discomfort and the risk of aspiration are among the shortcomings of this method, and an improved method is needed.Purpose
The purpose of this in vitro study was to examine the feasibility of a new method of palatography that uses airborne-particle–abraded acrylic resin so that wet areas can be easily distinguished from dry areas.Material and methods
Seventy-two specimens of heat-polymerized acrylic resin were prepared in 6 different resin colors. After the specimens had been airborne-particle abraded, CIELab color values for each specimen were measured using a colorimeter under dry and wet conditions and recorded. Color difference (ΔE) was then computed, and a paired Student t test, 1-way analysis of variance, and multiple comparison using the Tukey post hoc analysis were applied (α=.05).Results
A significant color difference was found between the 2 conditions in all acrylic resin specimens examined. Mean ΔE ranged from 5.58 to 6.76.Conclusions
The results indicated that an airborne-particle–abraded acrylic resin surface can show color differences made by wetting on palatograms. 相似文献16.
Statement of problem
Clinicians are aware that the vertical dimension of occlusion and the interocclusal rest space (IRS) are 2 major factors that require consideration in the management of patients needing oral reconstructive procedures. However, how the dimensions vary with age and prosthetic status is unclear.Purpose
The purpose of this clinical study was to analyze the IRS in dentate, partially edentulous, and completely edentulous participants using both conventional and electromyographic (EMG)-based methods. The effect of age and prosthodontic status on the clinical and EMG assessment of the IRS was also explored.Material and methods
The IRS was determined for a group of dentate (n=31) and partially edentate (n=31) participants, as well as a group of completely edentulous (n=31) participants who had worn dentures for at least 10 years before participating in the study. Clinical and EMG-based assessments (monitoring both elevator and depressor activity) were carried out using 5 different methods: rest, relaxing mask, phonetics, deglutition, and myobalance. Bivariate and multivariate analyses (forward stepwise linear regression models) were performed to compare the effect of age and prosthodontic status on the IRS (α=.05).Results
The average IRS values obtained from clinical and EMG-based assessments were significantly greater among dentate participants (2.8 ±0.4 mm and 3.6 ±0.6 mm, respectively) than partially edentulous (1.9 ±0.5 mm and 2.6 ±0.5 mm) and completely edentulous participants (1.4 ±0.5 mm and 2.2 ±0.6 mm). The IRS values obtained using the 5 methods of clinical assessment were statistically smaller than those obtained by EMG. Correlation and regression analyses showed that age and extended edentulism significantly decreased the IRS. For the IRS determined clinically, a decrease was found of 0.01 to 0.02 mm/year, based on the age of the participant. However, this decrease became greater (0.05 to 0.6 mm) where the participant had changed from being dentate to partially edentulous and partially edentulous to completely edentulous.Conclusions
The IRS becomes significantly smaller in relation to age and denture extension. The rest position in the clinical examination was located cranial to the position used to make the EMG-based measurement. Small but significant differences were found between the IRS values obtained in the clinical and EMG-based methods of assessment in all the prosthetic groups. 相似文献17.
Paulo Valdeci Worm Guilherme Finger Tobias Ludwig do Nascimento Carla Bittencourt Rynkowski Marcus Vinicius Martins Collares 《Journal of cranio-maxillo-facial surgery》2019,47(5):715-719
Objective
To evaluate the quality of life in patients with moderate or large cranial bone defects before and after late cranioplasty.Methods
Authors performed a prospective clinical trial including all consecutive patients that filled inclusion criteria during a period of 1 year. All patients answered the quality of life SF-36 questionnaire in 5 different times. Besides authors gathered information about the primary trauma and demographic characteristics.Results
A total of 70 consecutive patients were admitted to the hospital during the study period, and 62 were included in the project. Cranioplasty statistically improved patients' quality of life in all 8 domains after a 24 months follow-up.Conclusion
Cranioplasty has a significant impact over the quality of life in brain trauma victims who survived the primary trauma and harbor a large cranial bone defect. 相似文献18.
Mayuri Kerr Neil Park David Leeson Sergey Nikolskiy 《The Journal of prosthetic dentistry》2019,121(5):797-802
Statement of problem
Accuracy in impression making may be enhanced by digitizing the physical impression directly and thereby be unhampered by errors introduced by gypsum casts.Purpose
The purpose of this in vitro study was to compare the dimensional accuracy of microcomputed tomography (micro-CT) scans of impressions with that of optical scans of impressions and gypsum casts.Material and methods
A titanium maxillary cast with 3 metrology-grade ruby spheres in place of 3 teeth was used as a reference. Sphere 1 (S1) to sphere 2 (S2) distance (S1-S2) was 25.036 mm, and sphere 1 (S1) to sphere 3 (S3) distance (S1-S3) was 41.846 mm. Half-arch impressions were made of the titanium cast using polyvinyl siloxane impression material with a 1-step 2-phase technique. The polyvinyl siloxane impressions were then micro-CT scanned and optically scanned, and the resulting stone casts were also optically scanned. Scans from the 3 groups—CT scanning of impressions (CT), optical scanning of impressions (OP), and optical scanning of stone casts (SC)—were used to measure the distances between the 3 ruby spheres and were compared with the reference titanium model. The Wilcoxon signed-rank test for matched pairs was used to compare the groups (α=.01).Results
For the distance of 25.036 mm, S1-S2 distance, CT scans of impressions (CT) showed an error of 20 ±20 μm, whereas optical scans of stone casts (SC) showed an error of 0 ±20 μm. At a distance of 41.846 mm, S1-S3 distance, CT showed an error of 0 ±40 μm, whereas SC showed an error of ?40 ±40 μm. The difference in error between measurements at both distances was statistically significant (P<.01). The group of optical scans of impressions (OP) had to be excluded because of missing data and deformed features on the scan.Conclusions
Although optically scanned stone models are more dimensionally accurate than micro-CT scanned impressions at a 25.036-mm distance, at a distance of 41.846 mm, micro-CT scanned impressions showed less error than optically scanned stone models. Micro-CT scanning of half-arch impressions is a viable method of digitizing a physical impression of dental structures and capturing data about the patient's oral structures. A digital image obtained by micro-CT scanning is more accurate than that obtained by optical scans of stone casts for long-span restorations. 相似文献19.
20.
Oral Cenk Aktas Wolfgang Metzger Ayman Haidar Yahya Açil Aydin Gülses Jörg Wiltfang Catharina Marques Sacramento Frank Philipp Nothdurft 《Journal of cranio-maxillo-facial surgery》2019,47(4):661-667