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1.
J Clin Med ; 12(9)2023 Apr 24.
Article in English | MEDLINE | ID: mdl-37176531

ABSTRACT

(1) Background: Facial scanners are used in different fields of dentistry to digitalize the soft tissues of the patient's face. The development of technology has allowed the patient to have a 3-dimensional virtual representation, facilitating facial integration in the diagnosis and treatment plan. However, the accuracy of the facial scanner and the obtaining of better results with respect to the manual or two-dimensional (2D) method are questionable. The objective of this clinical trial was to evaluate the usefulness and accuracy of the 3D method (a dual-structured light facial scanner) and compare it with the 2D method (photography) to obtain facial analysis in the maximum intercuspation position and smile position. (2) Methods: A total of 60 participants were included, and nine facial landmarks and five interlandmarks distances were determined by two independent calibrated operators for each participant. All measurements were made using three methods: the manual method (manual measurement), the 2D method (photography), and the 3D method (facial scanner). All clinical and lighting conditions, as well as the specific parameters of each method, were standardized and controlled. The facial interlandmark distances were made by using a digital caliper, a 2D software program (Adobe Photoshop, version 21.0.2), and a 3D software program (Meshlab, version 2020.12), respectively. The data were analyzed by SPSS statistical software. The Kolmogorov-Smirnov test revealed that trueness and precision values were normally distributed (p > 0.05), so a Student's t-test was employed. (3) Results: Statistically significant differences (p ≤ 0.01) were observed in all interlandmark measurements in the 2D group (photography) to compare with the manual group. The 2D method obtained a mean accuracy value of 2.09 (±3.38) and 2.494 (±3.67) in maximum intercuspation and smile, respectively. On the other hand, the 3D method (facial scanner) obtained a mean accuracy value of 0.61 (±1.65) and 0.28 (±2.03) in maximum intercuspation and smile, respectively. There were no statistically significant differences with the manual method. (4) Conclusions: The employed technique demonstrated that it influences the accuracy of facial records. The 3D method reported acceptable accuracy values, while the 2D method showed discrepancies over the clinically acceptable limits.

2.
J Dent ; 121: 104138, 2022 06.
Article in English | MEDLINE | ID: mdl-35461973

ABSTRACT

PURPOSE: The purpose of this in vitro study was to evaluate the effect of ambient light illuminance on the accuracy and scanning time of different intraoral scanners (IOSs) in complete-arch implant scans. MATERIAL AND METHODS: Seven IOSs (TRIOS 3, Primescan, Element 5D, i700, i500, CS3700, and CS3600) at 5 ambient lighting illuminances (100, 500, 1000, 5000, and 10 000 lux) were evaluated. An edentulous cast with 4 implants was selected as the master model. An implant scan body was tightened on each implant. The cast was digitized by using a laboratory scanner to obtain a reference standard tessellation language (STL) file, and 50 scans (10 per ambient light condition) were recorded with each IOS. Scanning time was recorded by using a digital chronograph. Intraoral scan deviations were calculated by using a 3D metrology software program (Geomagic Control X). Kruskal-Wallis and pairwise comparison tests were used to analyze the data (α=0.05). RESULTS: The trueness and precision values obtained for each IOS tested were significantly different under the varying lighting conditions assessed. TRIOS 3 (34.0 ± 3.3 µm trueness; 24.5 ± 14.9 µm precision), Element 5D (34.5 ± 7.1 µm trueness; 25.9 ± 7.6 µm precision), and CS3700 (34.9. ±13.0 µm trueness; 34.6 ± 19.2 µm precision) performed better under 100 lux illumination, CS3600 (69.5 ± 24.0 µm trueness; 36.6 ± 20.1 µm precision) at 500 lux; i500 (36.2 ± 5.1 µm trueness; 21.4 ± 6.8 µm precision) at 1000 lux; i700 (34.8 ± 2.2 µm trueness; 15.4 ± 5.0 µm precision) at 5000 lux, and Primescan (37.4 ± 37.3 µm trueness; 26.2 ± 26.2 µm precision) at 10,000 lux. Additionally, the scanning time was different under different illuminance for each IOS. The fastest IOS in all light conditions was Primescan, with significant differences with all the groups (P<.01), followed by TRIOS 3 in all groups except under 100 lux illumination, where i700 was the second fastest. CONCLUSIONS: Ambient light influenced the accuracy and scanning time of IOSs assessed; however, the effect was not the same for all devices. It is necessary to optimize ambient light illuminance for each IOS to maximize scanning accuracy.


Subject(s)
Dental Impression Technique , Models, Dental , Computer-Aided Design , Dental Arch , Imaging, Three-Dimensional
3.
J Clin Exp Dent ; 14(1): e64-e71, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35070126

ABSTRACT

BACKGROUND: Clinical and radiographic evaluation of soft and hard tissues around convergent collar implants and shoulderless abutments. MATERIAL AND METHODS: Ambispective longitudinal analytical study with a sample size of 32 implants in 21 patients treated in a private dental clinic. Patients were divided into two groups: Prama Implants or group 1 (n=21) and Shelta implants combined with XA abutment or group 2 (n=11). Probing depth, horizontal mucosa thickness, peri-implant bone loss, plaque and bleeding after one-and two-year follow up are analyzed. RESULTS: In group 1, mean probing depth value was 1.67 mm (±0.58) and mean horizontal mucosa thickness value was 2.71 (±0.96). In group 2 mean probing depth was 2.18 (±0.40) and mean horizontal mucosa thickness value was 3.27 mm (±1.19). In group 1 an 85.7% of peri-implant bone level was maintained and a 14.3% increased. In group 2 a 100% of peri-implant bone level was maintained. In group 1 a 19% presented plaque when crowns were removed and in group 2 a 18.2% presented plaque. Neither of two groups presented spontaneous bleeding when crowns were removed. A 52.4% presented probing bleeding in group 1 and a 45.4% in group 2. CONCLUSIONS: Biologically guided crowns design seems to provide peri-implant hard and soft tissue stability. Key words:Biologic width, peri-implant soft tissue, marginal bone loss, transmucosal implant, convergent collar, BOPT (biological oriented preparation technique), BOPT abutment, soft tissue stability.

4.
J Clin Exp Dent ; 13(12): e1209-e1215, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34987713

ABSTRACT

BACKGROUND: Intraoral scanner evaluation (3Shape, TRIOS®) of soft tissue thickness around convergent collar implants and shoulderless abutments. MATERIAL AND METHODS: Ambispective longitudinal analytical study with a sample size of 26 implants in 17 patients treated in a private dental clinic. Pacients were divided into two groups: Prama Implants or group 1 (n=19) and Shelta implants combined with XA abutment or group 2 (n=7). Thickness changes after one- and two-year follow-up were analyzed. RESULTS: In group 1 baseline mean thickness was 6.53 mm (±1.06) and follow-up mean thickness was 8.06 mm (±0.98), in group 2 initial mean thickness was 7.66 mm (±1.09) and follow-up mean thickness was of 8.42 mm (±1.03). CONCLUSIONS: Biologically guided crowns design seems to significantly increase the soft tissue volumen around convergent morphology implants. Key words:Biologic width, peri-implant soft tissue, marginal bone loss, transmucosal implant, convergent collar, BOPT (biological oriented preparation technique), BOPT abutment, soft tissue stability, intraoral scanner.

5.
Cient. dent. (Ed. impr.) ; 13(2): 155-160, mayo-ago. 2016. ilus, tab
Article in Spanish | IBECS | ID: ibc-155291

ABSTRACT

Objetivos: Comparar la resistencia a la fractura de estructuras de fibra de carbono con estructuras de cobalto-cromo, unidas a resina y tras termociclado. Materiales y métodos: se confeccionaron cinco probetas de fibra de carbono y cinco de cromo-cobalto y se unieron a resina acrílica. Ambas probetas se sometieron a 5000 ciclos de termociclado, permaneciendo durante 30 segundos en saliva artificial entre 5º y 55º C de temperatura entre cada ciclo. Posteriormente se realizó un ensayo por carga en tres puntos hasta producirse fractura de las probetas. Resultados: Dos de las cinco probetas de fibra de carbono presentaron separación de los materiales tras el termociclado. El grupo de fibra de carbono obtuvo valores más bajos en la resistencia a la fractura (305,6 N), mientras que el grupo de cromo-cobalto alcanzó los 664,8 N de media (p=0,008). Conclusiones: Dentro de los límites del estudio, la resistencia a la fractura de las probetas de fibra de carbono fue significativamente menor que la de las probetas de cromo-cobalto. Es necesario mejorar las estructuras para poder indicar este material como alternativa al cromo-cobalto en prótesis híbridas implantosoportadas (AU)


Objective: To compare the resistance to fracture of carbon fiber and acrylic resin structures and with cobalt-chromium alloy and acrilic resin structures after thermal cycling. Material and methods: Five carbon fiber reinforced acrylic resin and five cobalt-chromium alloy embebed in acrylic resin specimens were fabricated. All specimens were thermal cycled from 5º to 55ºC for 5000 cycles with a 30-s dwell time. A three point loading test until fracture of specimens was performed. Results: In two of five specimens separation of carbon fiber from acrylic resin was observed after thermal cycling. The carbon fiber reinforced group presented lower resistance values (305,6 N) while cobalt-chromium group reached an average of 664,8 N (p=0.008). Conclusions: Within the limitations of this study, the resistance to fracture of carbon fiber specimens were significantly lower than cobalt-chormium group. More studies and improvment of carbon fiber reinforced resins are necessary in order to be used as alternative material for implant-supported hybrid prosthesis (AU)


Subject(s)
Humans , Carbon/analysis , Dental Materials/analysis , 51660/methods , Chromium Alloys/analysis , Dental Prosthesis
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