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1.
Artículo en Inglés | MEDLINE | ID: mdl-39098862

RESUMEN

Estimating chronological age is crucial in forensic identification. The increased application of medical imaging in age analysis has facilitated the development of new quantitative methods for the macroscopic evaluation of bones. This study aimed to determine the association of age-related changes in the trabecular microstructure with chronological age for age estimation in forensic science through different non-invasive imaging techniques. This systematic review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. An electronic search was performed with PubMed/MEDLINE, Scopus, and Cochrane databases as well as with a Google Scholar search. Qualitative synthesis was performed using the Anatomical Quality Assessment tool. A detailed literature search yielded 3467 articles. A total of 14 articles were ultimately included in the study. A narrative approach was employed to synthesize the data. Microcomputed tomography, high-resolution peripheral quantitative computed tomography, and cone beam computed tomography have been used for the quantitative estimation of age. These imaging techniques aid in identifying the trabecular bone microarchitectural parameters for chronological age estimation. Age-related changes in trabecular bone included a decrease in the bone volume fraction, trabecular number, and connectivity density and an increase in trabecular separation. This study also revealed that morphometric indices vary with age and anatomical site. This study is registered with the International Prospective Register of Systematic Reviews (PROSPERO) with the registration number CDRD42023391873.

2.
Int J Legal Med ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940946

RESUMEN

Cranial vault thickness (CVT) and its variations provide valuable insights into an individual's biological attributes such as age and sex. This paper aimed to assess the correlations of CVT with age and sex and develop a regression model for age estimation in Malaysian subadults using computed tomography (CT) images. A total of 521 CT images (male/female: 279/242; age range: 0-20 years; Malay/Chinese/Indian: 221/145/155) were included in the study. Correlations of CVT measurements with age and sex, including frontal bone thickness (FBT), occipital bone thickness (OBT), left parietal bone thickness (LPBT), and right parietal bone thickness (RPBT) were assessed and regression formulae were developed for age estimation in subadults. A significant correlation between CVT measurements and age was demonstrated (p < 0.001). Age estimation was most accurate in the younger age group (< 2 years) at frontal and occipital, and accuracy decreases in the older age groups. Additionally, sexual dimorphism was evident in the frontal and parietal bone thickness within the age range of 3-6 years and 16-20 years, respectively. In conclusion, the findings suggested CVT measurements could be used to corroborate other age estimation methods for subadults.

3.
J Prosthet Dent ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38627176

RESUMEN

STATEMENT OF PROBLEM: Three-dimensional (3D) printing of cobalt chromium (Co-Cr) removable partial dentures (RPDs)by selective laser melting (SLM) has been claimed to be less challenging than by conventional casting and provides significant improvements. However, the adaptation and fit of the SLM framework and the optimum build orientation are still unclear. PURPOSE: The purpose of this in vitro and clinical study was to evaluate the effect of different build orientations on the adaptation of removable partial denture frameworks fabricated by SLM technology in vitro and to compare the adaptation of the SLM and conventional RPD frameworks clinically. MATERIAL AND METHODS: A master model simulating a maxillary arch of Kennedy class III modification 1 was scanned and duplicated to create a virtual 3D cast and reference cast. Four groups (n=40) of Co-Cr RPD frameworks were fabricated. For the SLM groups, the Co-Cr framework was virtually designed and exported for SLM printing. The SLM printing was done in 3 different build orientations: 0-degree (n=10), 45-degree (n=10), and 90-degree (n=10) groups. Other Co-Cr frameworks were conventionally cast (n=10). All Co-Cr frameworks were scanned and virtually superimposed with the master model using a surface-matching software program. The gap under 9 selected points in the palatal major connectors was analyzed and calculated. A smaller gap indicates more surface adaptation and close contact between the palatal major connector and the master model. The data were analyzed using the Kruskal-Wallis and Dunnett T3 tests (α=.05). Three patients with a partially dentate maxillary arch were enrolled in the clinical part based on inclusion criteria. Two RPD frameworks were provided for each patient (conventional casting and SLM printing). The adaptation of each framework was assessed by measuring the gap between the palatal major connector of the framework and the palate with light-body silicone. The differences in adaptation between the conventional and SLM frameworks were compared by using independent t tests (α=.05). RESULTS: The in vitro study identified significant differences in the adaptation of the palatal major connector among the 4 groups (P<.001), except for conventional and 0-degree SLM printing (P=.999). The conventional and 0-degree SLM frameworks exhibited the best adaptation, with the lowest gap underneath the palatal major connector of the RPD framework (0.01 ±0.02 mm and 0.01 ±0.01 mm, respectively). In the clinical part of the study, no significant difference was found between the adaptation of SLM and the conventional framework (P=.430) CONCLUSIONS: The adaptation of SLM printing can be maximized with less gap under the palatal major connector of the RPD framework when using the 0-degree build orientation. Co-Cr frameworks produced with SLM printing technology were comparable with conventionally produced frameworks; hence, SLM printed frameworks can be an alternative for clinical applications when optimum SLM parameters are applied.

4.
BMC Oral Health ; 24(1): 252, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373931

RESUMEN

BACKGROUND: Artificial intelligence has been proven to improve the identification of various maxillofacial lesions. The aim of the current study is two-fold: to assess the performance of four deep learning models (DLM) in external root resorption (ERR) identification and to assess the effect of combining feature selection technique (FST) with DLM on their ability in ERR identification. METHODS: External root resorption was simulated on 88 extracted premolar teeth using tungsten bur in different depths (0.5 mm, 1 mm, and 2 mm). All teeth were scanned using a Cone beam CT (Carestream Dental, Atlanta, GA). Afterward, a training (70%), validation (10%), and test (20%) dataset were established. The performance of four DLMs including Random Forest (RF) + Visual Geometry Group 16 (VGG), RF + EfficienNetB4 (EFNET), Support Vector Machine (SVM) + VGG, and SVM + EFNET) and four hybrid models (DLM + FST: (i) FS + RF + VGG, (ii) FS + RF + EFNET, (iii) FS + SVM + VGG and (iv) FS + SVM + EFNET) was compared. Five performance parameters were assessed: classification accuracy, F1-score, precision, specificity, and error rate. FST algorithms (Boruta and Recursive Feature Selection) were combined with the DLMs to assess their performance. RESULTS: RF + VGG exhibited the highest performance in identifying ERR, followed by the other tested models. Similarly, FST combined with RF + VGG outperformed other models with classification accuracy, F1-score, precision, and specificity of 81.9%, weighted accuracy of 83%, and area under the curve (AUC) of 96%. Kruskal Wallis test revealed a significant difference (p = 0.008) in the prediction accuracy among the eight DLMs. CONCLUSION: In general, all DLMs have similar performance on ERR identification. However, the performance can be improved by combining FST with DLMs.


Asunto(s)
Aprendizaje Profundo , Resorción Radicular , Tomografía Computarizada de Haz Cónico Espiral , Humanos , Resorción Radicular/diagnóstico por imagen , Inteligencia Artificial , Tomografía Computarizada de Haz Cónico
5.
Leg Med (Tokyo) ; 66: 102391, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38211402

RESUMEN

Three-dimensional surface area analyses of developing root apices for age estimation in children and young adults have shown promising results. The current study aimed to apply this three-dimensional method to develop a regression model for estimating age in Malaysian children aged 7 to 14 using developing maxillary second premolars. A training sample of 155 cone-beam computed tomography scans (83 Malays and 72 Chinese) was analysed, and the formula was subsequently validated on an independent sample of 92 cone-beam computed tomography scans (45 Malays and 47 Chinese). The results showed a strong correlation (r = 94 %) between the chronological age as a dependent variable and the predictor variables, including root surface area of the apex, sex, ethnicity, and root development status (open/closed apices). For this model, the predictor variables accounted for 88.4 % of the variation in age except sex and ethnicity. A mean absolute error value of 0.42 indicated that this model can be reliably used for Malaysian children. In conclusion, this study recognises the method of three-dimensional surface area analyses as a valuable tool for age estimation in forensic and clinical practice. Further studies are highly recommended to assess its effectiveness across different demographic groups.


Asunto(s)
Determinación de la Edad por los Dientes , Tomografía Computarizada de Haz Cónico Espiral , Niño , Humanos , Pueblo Asiatico , Diente Premolar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Maxilar/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Adolescente
6.
Odontology ; 112(2): 570-587, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37957521

RESUMEN

This study aims to evaluate the number of roots and root canal morphology types of maxillary premolars in relation to a patient's gender and age in an Iraqi population using two classification systems. Cone beam computed tomography (CBCT) scans of 1116 maxillary premolars from 385 patients were evaluated for the number of roots and root canal morphology types according to Vertucci's classification and Ahmed et al. classification systems. Differences in the number of roots and root canal morphology types with regard to tooth type, patients' gender and age groups were evaluated and the degree of bilateral symmetry was determined. Chi-squared test was used for statistical analysis. About 51.1% of the 1st premolars were double rooted. The majority (87.9%) of the 2nd premolars were single rooted. The three-rooted form presented in only 1.2% and 0.7% of the 1st and 2nd premolars, respectively. Vertucci Type IV (Ahmed et al. code 2MaxP B1P1) and Vertucci Type I (Ahmed et al. code 1MaxP1) were the most common canal morphology types in the 1st and 2nd premolars, respectively. Females showed a lower number of roots and a higher prevalence of Vertucci Type I configuration (P < 0.05). Younger age groups showed a higher prevalence of Vertucci Type I configuration (P < 0.05). Bilateral symmetry was seen in more than half of the maxillary premolars. There is a considerable variation in the number of roots and root canal configurations of maxillary premolars in the studied Iraqi population, with a significant difference by gender and age groups. Ahmed et al. classification provided more accurate presentation of the root and canal anatomy in maxillary premolars compared to Vertucci's classification.


Asunto(s)
Cavidad Pulpar , Raíz del Diente , Femenino , Humanos , Diente Premolar/diagnóstico por imagen , Diente Premolar/anatomía & histología , Cavidad Pulpar/diagnóstico por imagen , Irak , Raíz del Diente/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos
7.
J Dent Educ ; 87(8): 1089-1098, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37164913

RESUMEN

PURPOSE: To assess the application and accuracy of two systems (Vertucci et al. 1974 and Ahmed et al. 2017) in classifying the root and canal morphology of human dentition among final-year undergraduates, interns, and postgraduate dental students in India. METHODS: The survey was conducted using physical and online presentation modes in two phases. Phase 1; PowerPoint presentation (PPT), describing the most used classification system (Vertucci et al. 1974) and its supplementary types and Ahmed et al. (2017) classification. A single presenter delivered the PPT to participants, using either a projector in an auditorium/seminar hall (face-to-face) or an online platform (zoom meeting software). Phase 2 involved determining the students' responses. A questionnaire was distributed amongst the participants after the lecture and collected for analysis. Fisher's exact test was used to analyze the data statistically, and the significance level was set at 0.05 (p < 0.05). RESULTS: A total of 1082 participants were involved in this survey. Overall, 93% of study participants found that Ahmed et al. classification system was more practical and accurate than Vertucci et al. system and its supplemental configurations (p < 0.001). About 97% agreed that Ahmed et al. classification system aided in understanding root and canal morphology better than Vertucci's and its additional configurations, and they recommended to include in their curriculum (p < 0.001). CONCLUSIONS: In comparison to Vertucci's classification system and supplementary types, the undergraduate and postgraduate dental students, and interns in India agreed that Ahmed et al. classification system is more practical and accurate for classifying the root and canal morphology.


Asunto(s)
Dentición , Raíz del Diente , Humanos , Raíz del Diente/anatomía & histología , Cavidad Pulpar/anatomía & histología , Estudiantes , India , Tomografía Computarizada de Haz Cónico
8.
Leg Med (Tokyo) ; 64: 102275, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37229938

RESUMEN

Sex estimation is crucial in biological profiling of skeletal human remains. Methods used for sex estimation in adults are less effective for sub-adults due to varied cranium patterns during the growth period. Hence, this study aimed to develop a sex estimation model for Malaysian sub-adults using craniometric measurements obtained through multi-slice computed tomography (MSCT). A total of 521 cranial MSCT dataset of sub-adult Malaysians (279 males, 242 females; 0-20 years old) were collected. Mimics software version 21.0 (Materialise, Leuven, Belgium) was used to construct three-dimensional (3D) models. A plane-to-plane (PTP) protocol was utilised to measure 14 selected craniometric parameters. Discriminant function analysis (DFA) and binary logistic regression (BLR) were used to statistically analyze the data. In this study, low level of sexual dimorphism was observed in cranium below 6 years old. The level was then increased with age. For sample validation data, the accuracy of DFA and BLR in estimating sex improved with age from 61.6% to 90.3%. All age groups except 0-2 and 3-6 showed high accuracy percentage (≥75%) when tested using DFA and BLR. DFA and BLR can be utilised to estimate sex for Malaysian sub-adult using MSCT craniometric measurements. However, BLR showed higher accuracy than DFA in sex estimation of sub-adults.


Asunto(s)
Antropología Forense , Determinación del Sexo por el Esqueleto , Masculino , Femenino , Adulto , Humanos , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto Joven , Antropología Forense/métodos , Determinación del Sexo por el Esqueleto/métodos , Cefalometría , Cráneo/diagnóstico por imagen , Cráneo/anatomía & histología , Análisis Discriminante , Restos Mortales , Tomografía Computarizada Multidetector , Imagenología Tridimensional
9.
Biology (Basel) ; 11(10)2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36290424

RESUMEN

The aim of this study is two-fold: first, to correlate the values for each of the trabecular bone microstructure (TBM) parameters to the individual's chronological age and sex, thereby facilitating the assessment of potential age and sex-related changes in trabecular bone microstructure parameters in the mandible; and second, to quantify the trabecular microstructural parameters in relation to chronological age. Twenty cone-beam computed tomographic (CBCT) scans were retrieved retrospectively from a database of adult patients with ages ranging in age from 22 to 43 years. In the mandible, the volume of interest included the inter-dental space between the second mandibular premolar and the first mandibular molar, as well as the trabecular space beneath and between the apices. Using the AnalyzeDirect 14.0 software, the DICOM images of CBCT scans were pre-processed, transformed, segmented using a novel semi-automatic threshold-guided method, and quantified. In addition, TBM parameters were derived, and statistical analysis was conducted using a Pearson correlation test with two tails. All parameters exhibited no statistically significant differences (p > 0.05) between chronological age and sex. Statistically significant negative correlations were found between Tb. N (r = −0.489), BS/TV (r = −0.527), and chronological age (p = 0.029 and p = 0.017, respectively). Only Tb. N and BS/TV exhibited an inverse relationship with chronological age. Numerous studies have quantified the trabecular architecture of the jaw bones, but none have found a correlation between the quantified trabecular parameters and chronological age. The digital imprints produced by radiographic imaging can serve as biological profiles for data collection.

10.
J Prosthet Dent ; 128(3): 530.e1-530.e7, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35933173

RESUMEN

STATEMENT OF PROBLEM: Additive manufacturing by selective laser melting (SLM) has been claimed to be less challenging than conventional casting of cobalt-chromium (Co-Cr) removable partial dentures (RPDs), providing significant improvements. However, how the physicomechanical properties of Co-Cr RPDs fabricated by SLM compare with those fabricated by conventional casting is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the physicomechanical properties of Co-Cr RPD palatal major connectors fabricated by SLM compared with those fabricated by conventional casting. MATERIAL AND METHODS: A master die simulating a maxillary arch of Kennedy class III modification 1 was scanned to create a virtual 3-dimensional (3D) cast. Two groups of 5 Co-Cr RPD major connectors were fabricated. In the 3D printing group, the Co-Cr major connector was virtually designed and exported for direct SLM 3D printing. For the conventional group, Co-Cr major connectors were constructed conventionally. The Co-Cr major connectors were virtually superimposed with the master die for surface adaptation analysis. Additional comparative analyses of surface roughness, relative density, microhardness, and microstructure of the 2 groups were performed. Data were analyzed by using independent t tests (α=.05). RESULTS: The overall volumetric and linear discrepancies were significantly higher (P<.05) in the 3D printing group. Significant differences in the surface roughness (P<.05) and microhardness (P<.05) were observed, with the 3D printing group having higher surface roughness and microhardness than the conventional group. Unlike conventional connectors, the microstructure of 3D-printed connectors showed fine homogeneous granules. CONCLUSIONS: Compared with the conventional casting technique, SLM 3D printing enabled the fabrication of Co-Cr RPD major connectors with higher microhardness and fine homogenous microstructure. However, the surface adaptation and surface roughness of SLM 3D printing Co-Cr connectors were worse than those produced conventionally. Both techniques showed similar relative densities.


Asunto(s)
Dentadura Parcial Removible , Cromo , Aleaciones de Cromo/química , Cobalto , Rayos Láser , Fenómenos Químicos
11.
Ann Hum Biol ; 49(2): 109-115, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35535801

RESUMEN

AIM: This study compared the effectiveness of the three-dimensional (3D) cone beam computed tomography (CBCT) method of age estimation developed by Asif et al. with two-dimensional Cameriere's method. SUBJECTS AND METHODS: CBCT images belonging to 129 Malaysian Chinese and Malay ethnic groups aged 7-14 years were investigated and analysed. RESULTS: The results indicated a strong correlation between chronological age and the predictor variables for both Cameriere's (r = 0.984) and Asif's (r = 0.988) methods of age estimation. Fisher Z test analysis indicated no statistically significant difference in the correlation values between the two methods. Mean absolute error (MAE) value of 0.613 was observed for Cameriere's and 0.290 was observed for Asif's method. CONCLUSIONS: The results indicated that the methods of age estimation from both Asif et al. and Cameriere et al. are applicable on Malaysian children. However, Asif et al.'s 3D CBCT method of age estimation resulted in greater accuracy and reliability in estimating chronological age.


Asunto(s)
Determinación de la Edad por los Dientes , Determinación de la Edad por los Dientes/métodos , Pueblo Asiatico , Niño , Etnicidad , Humanos , Imagenología Tridimensional , Radiografía Panorámica , Reproducibilidad de los Resultados
12.
J Taibah Univ Med Sci ; 17(2): 289-296, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35592796

RESUMEN

Objective: To determine the effects of repeated placement of quantified lyophilised platelet-rich plasma (LPRP) on the soft and hard tissue components. Methods: Lyophilised platelet-rich plasma was topically placed, and later injected, into fresh sockets using the third molar surgical model, randomised according to the split-mouth approach. The control site received placebo. The application of LPRP was done intraoperatively, one month and two months postoperatively. The measured endpoints included post-operative pain, swelling, trismus, pocket depth at mid-distal adjacent second molar, soft tissue healing, and bone formation (which was assessed radiographically). Fifteen healthy young adults, aged between 21 and 35 years, visiting the Oral and Maxillofacial Surgery Clinic at the University of Malaya were recruited for this study. Results: There was no significant difference in post-operative pain, swelling size, trismus, and bone healing within their specific timelines during this study. However, the LPRP group showed significant reduction in pocket depth at the two-month post-operative period, suggesting that LPRP improves soft tissue healing. Conclusion: Soft tissue healing, measured as the change of periodontal pocket depth, showed significant reduction, suggesting the benefit of LPRP for soft tissue healing. However, bone regeneration and reduction of post-operative sequelae showed no improvement even after quantification and repeated LPRP application.

13.
J Craniomaxillofac Surg ; 49(12): 1175-1181, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34247917

RESUMEN

The aim of this study was to compare optic canal parameters of syndromic craniosynostosis patients with those of normal patients to visit the possibility of optic nerve impingement as a cause of visual impairment. Computed tomography scan images were processed using the Materialise Interactive Medical Image Control System (MIMICS) Research 21.0 software (Materialise NV, Leuven, Belgium). Eleven optic canal parameters were measured: 1) height of optic canal on the cranial side, 2) height of optic canal on the orbital side 3) length of the medial wall of the optic canal, 4) length of the lateral canal wall of the optic canal, 5) diameter of the optic canal at five points (Q1-Q4 and mid canal), and 6) area and perimeter of optic canal. These measurements were obtained for both the right and left optic canals. The study sample comprised four Crouzon syndrome, five Apert syndrome, and three Pfeiffer syndrome patients. The age of these syndromic craniosynostosis patients ranged from 2 to 63 months. The height of the optic canal on the orbital side (p = 0.041), diameter of the mid canal (p = 0.040), and diameter between the mid-canal and the cranial opening (Q3) (p = 0.079) for syndromic craniosynostosis patients were statistically narrower compared with those of normal patients when a significance level of 0.1 was considered. Scatter plots for the ages of patients versus the above parameters gave three separated clusters that suggested the arresting of optic canal development with age. The findings from this study demonstrated a narrowing of the optic canal in syndromic craniosynostosis patients, and indicate that optic canal anatomical characteristics may have an association with visual impairment among pediatric syndromic craniosynostosis patients.


Asunto(s)
Acrocefalosindactilia , Disostosis Craneofacial , Craneosinostosis , Acrocefalosindactilia/complicaciones , Acrocefalosindactilia/diagnóstico por imagen , Niño , Preescolar , Disostosis Craneofacial/complicaciones , Disostosis Craneofacial/diagnóstico por imagen , Craneosinostosis/diagnóstico por imagen , Humanos , Lactante , Hueso Esfenoides , Tomografía Computarizada por Rayos X
14.
BMC Oral Health ; 21(1): 249, 2021 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-33964918

RESUMEN

BACKGROUND: The aim of this study was to compare the trabecular bone microstructures of anterior and posterior edentulous regions of human mandible using cone-beam computed tomography (CBCT) and micro computed tomography (µCT). METHODS: Twenty volumes of interests consisting of six anterior and fourteen posterior edentulous regions were obtained from human mandibular cadavers. A CBCT system with a resolution of 80 µm (3D Accuitomo 170, J. Morita, Kyoto, Japan) and a µCT system with a resolution of 35 µm (SkyScan 1173, Kontich, Belgium) were used to scan the mandibles. Three structural parameters namely, trabecular number (Tb.N), trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp) were analysed using CTAn software (v 1.11, SkyScan, Kontich, Belgium). For each system, the measurements obtained from anterior and posterior regions were tested using independent sample t-test. Subsequently, all measurements between systems were tested using paired t-test. RESULTS: In CBCT, all parameters of the anterior and posterior mandible showed no significant differences (p > 0.05). However, µCT showed a significant different of Tb.Th (p = 0.023) between anterior and posterior region. Regardless of regions, the measurements obtained using both imaging systems were significantly different (p ≤ 0.021) for Tb.Th and Tb.N. CONCLUSIONS: The current study demonstrated that only the variation of Tb.Th between anterior and posterior edentulous region of mandible can be detected using µCT. In addition, CBCT is less feasible than µCT in assessing trabecular bone microstructures at both regions.


Asunto(s)
Hueso Esponjoso , Mandíbula , Bélgica , Hueso Esponjoso/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Humanos , Japón , Mandíbula/diagnóstico por imagen , Microtomografía por Rayos X
15.
J Indian Prosthodont Soc ; 21(2): 198-203, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33938871

RESUMEN

Aim: To investigate the effect of different cooling methods on denture base adaptation of rapid heat-cured acrylic resin using 3D superimposition technique. Setting and Design: In vitro - Comparative study. Materials and Methods: Denture base adaptation of two different rapid heat-cured polymethyl methacrylate acrylic resins using five different cooling methods were compared. Forty maxillary edentulous stone cast were prepared to produce the denture bases with standardized thickness. The specimens were divided into five groups (n = 8) according to type of materials and cooling methods. The master stone cast and all forty denture bases were scanned with 3Shape E1 laboratory scanner. The scanned images of each of the denture bases were superimposed over the scanned image of the master cast using Materialize 3-matic software. Three dimensional differences between the two surfaces were calculated and color surface maps were generated for visual qualitative assessment. Statistical Analysis Used: Generalized Linear Model Test, Bonferroni Post Hoc Analysis. Results: All bench-cooled specimens showed wide green-colored area in the overall palatal surface, while the rapid cooled specimens presented with increased red color areas especially at the palate and post dam area. Generalized Linear Model test followed by Bonferroni post hoc analysis showed significant difference in the root mean square values among the specimen groups. Conclusion: Samples that were bench cooled, demonstrated better overall accuracy compared to the rapid cooling groups. Regardless of need for shorter denture processing time, bench cooling of rapid heat-cured PMMA is essential for acceptable denture base adaptation.


Asunto(s)
Bases para Dentadura , Calor , Resinas Acrílicas , Humanos , Transición de Fase , Polimetil Metacrilato
17.
J Craniofac Surg ; 32(1): 355-359, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33156163

RESUMEN

BACKGROUND: In syndromic craniosynostosis (SC), unlike persistent corneal irritation due to severe exophthalmos and increased intracranial pressure, optic canal (OC) stenosis has been scarcely reported to cause visual impairment. This study aimed to validate the OC volumetric and surface area measurement among SC patients. METHODS: Sixteen computed tomography scan of SC patients (8 months-6 years old) were imported to Materialise Interactive Medical Image Control System (MIMICS) and Materialise 3-matics software. Three-dimensional (3D) OC models were fabricated, and linear measurements were obtained. Mathematical formulas were used for calculation of OC volume and surface area from the 3D model. The same measurements were obtained from the software and used as ground truth. Data normality was investigated before statistical analyses were performed. Wilcoxon test was used to validate differences of OC volume and surface area between 3D model and software. RESULTS: The mean values for OC surface area for 3D model and MIMICS software were 103.19 mm2 and 31.27 mm2, respectively, whereas the mean for OC volume for 3D model and MIMICS software were 184.37 mm2 and 147.07 mm2, respectively. Significant difference was found between OC volume (P = 0.0681) and surface area (P = 0.0002) between 3D model and software. CONCLUSION: Optic canal in SC is not a perfect conical frustum thus making 3D model measurement and mathematical formula for surface area and volume estimation not ideal. Computer software remains the best modality to gauge dimensional parameter and is useful to elucidates the relationship of OC and eye function as well as aiding intervention in SC patients.


Asunto(s)
Craneosinostosis , Imagenología Tridimensional , Craneosinostosis/diagnóstico por imagen , Humanos , Programas Informáticos , Tomografía Computarizada por Rayos X
18.
Angle Orthod ; 90(6): 774-782, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-33378515

RESUMEN

OBJECTIVES: To investigate the effect of micro-osteoperforation (MOP) on the horizontal and vertical distribution of mandibular trabeculae bone volume fraction in relation to different MOP intervals during canine retraction. MATERIALS AND METHODS: This single-center, single-blinded, prospective randomized split-mouth clinical trial included 30 healthy participants aged 18 years and older, randomized into three groups of different MOP intervals (4, 8, and 12-weekly). Cone beam computed tomography images were taken to assess the bone volume fraction (bone volume over total volume or BV/TV). RESULTS: BV/TV was significantly reduced (mean difference: 9.79%, standard deviation [SD]: 11.89%; 95% confidence interval [CI]: 4.77, 14.81%; P < .01) and canine retraction increased (mean difference: -1.25 mm/4 mo, SD: 0.79 mm; 95% CI: -1.59, -0.92 mm; P < .01) with MOP, compared to control sites. MOP significantly changed the vertical and horizontal patterns of trabeculae bone with lower values nearer to intervention sites. Only the 4-weekly MOP interval group showed significant decrease in BV/TV (mean difference: 14.73%, SD: 12.88%; 95% CI: 3.96, 25.50%; P = .01) despite significant increase in canine retraction rate for all interval groups. With the use of MOP, BV/TV was found to be inversely correlated to the rate of canine retraction (r = -0.425; P = .04). CONCLUSIONS: Mandibular trabecular alveolar bone volume fraction was reduced and rate of orthodontic tooth movement increased with MOP, especially in the 4-weekly interval. However, this effect was limited to the immediate interdental region of MOP.


Asunto(s)
Mandíbula , Técnicas de Movimiento Dental , Adolescente , Tomografía Computarizada de Haz Cónico , Humanos , Mandíbula/diagnóstico por imagen , Boca , Estudios Prospectivos
19.
Am J Orthod Dentofacial Orthop ; 158(4): 579-586.e1, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32826123

RESUMEN

INTRODUCTION: The study aimed to investigate the effects of micro-osteoperforations (MOPs) on the mandibular bone volume/tissue volume (BV/TV) ratio changes and the rate of orthodontic tooth movement using cone-beam computed tomography images. Another objective was to evaluate the effects of MOP frequency intervals (4 weeks, 8 weeks, and 12 weeks) on the BV/TV ratio and rate of tooth movement. METHODS: In 24 participants, 140-200 g of force was applied for mandibular canine retraction. Three MOPs were made according to the scheduled intervals of the 3 different groups: group 1 (MOP 4 weeks), group 2 (MOP 8 weeks), and group 3 (MOP 12 weeks) directly at the mandibular buccal cortical bone of extracted first premolars sites. Cone-beam computed tomography scans were obtained at the 12th week after MOP application. Computed tomography Analyzer software (version 1.11.0.0; Skyscan, Kontich, Belgium) was used to compute the trabecular alveolar BV/TV ratio. RESULTS: A significant difference was observed in the rate of canine movement between control and MOP. Paired t test analysis showed a significant difference (P = 0.001) in the mean BV/TV ratio between control and MOP sides in all the frequency intervals groups. However, the difference was significant only in group 1 (P = 0.014). A strong negative correlation (r = -0.86) was observed between the rate of canine tooth movement and the BV/TV ratio at the MOP side for group 1 and all frequency intervals together (r = -0.42). CONCLUSIONS: The rate of orthodontic tooth movement can be accelerated by the MOP technique with frequently repeated MOPs throughout the treatment.


Asunto(s)
Diente Canino/diagnóstico por imagen , Técnicas de Movimiento Dental , Diente Premolar , Tomografía Computarizada de Haz Cónico , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía
20.
J Dent ; 101: 103455, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32828845

RESUMEN

OBJECTIVES: This clinical study assessed and compared the linear and volumetric changes of extraction sockets grafted with a combination of Platelet-Rich Fibrin (PRF) and Calcium Sulfate (CS) (PRF-CS), and extraction sockets grafted with a combination of PRF and xenograft (X) (PRF-X). METHODS: Five single maxillary premolar extraction sockets received PRF-CS grafts and five single maxillary premolar sockets received PRF-X grafts. Linear (horizontal and vertical) measurements were accomplished using Cone Beam Computed Tomography (CBCT) images and volumetric changes were assessed using MIMICS software. Soft tissue level changes were measured using Stonecast models. All measurements were recorded at baseline (before extraction) and at 5-months post-extraction. RESULTS: Significant reduction in vertical and horizontal dimensions were observed in both groups except for distal bone height (DBH = 0.44 ±â€¯0.45 mm, p = 0.09) and palatal bone height (PBH = 0.39 ±â€¯0.34 mm, p = 0.06) in PRF-X group. PRF-CS group demonstrated mean horizontal shrinkage of 1.27 ±â€¯0.82 mm (p = 0.02), when compared with PRF-X group (1.40 ±â€¯0.85 mm, p = 0.02). Vertical resorption for mesial bone height (MBH = 0.56 ±â€¯0.25 mm, p = 0.008), buccal bone height (BBH = 1.62 ±â€¯0.91 mm, p = 0.01) and palatal bone height (PBH = 1.39 ±â€¯0.87 mm, p = 0.02) in PRF-CS group was more than resorption in PRF-X group (MBH = 0.28 ±â€¯0.14 mm, p = 0.01, BBH = 0.63 ±â€¯0.39 mm, p = 0.02 and PBH = 0.39 ±â€¯0.34 mm, p = 0.06). Volumetric bone resorption was significant within both groups (PRF-CS = 168.33 ±â€¯63.68 mm3, p = 0.004; PRF-X = 102.88 ±â€¯32.93 mm3, p = 0.002), though not significant (p = 0.08) when compared between groups. In PRF-X group, the distal soft tissue level (DSH = 1.00 ±â€¯0.50 mm, p = 0.03) demonstrated almost 2 times more reduction when compared with PRF-CS group (DSH = 1.00 ±â€¯1.00 mm, 0.08). The reduction of the buccal soft tissue level was pronounced in PRF-CS group (BSH = 2.00 ±â€¯2.00 mm, p = 0.06) when compared with PRF-X group (BSH = 1.00 ±â€¯1.50 mm, p = 0.05). CONCLUSIONS: PRF-CS grafted sites showed no significant difference with PRF-X grafted sites in linear and volumetric dimensional changes and might show clinical benefits for socket augmentation. The study is officially registered with ClinicalTrials.gov Registration (NCT03851289).


Asunto(s)
Pérdida de Hueso Alveolar , Fibrina Rica en Plaquetas , Pérdida de Hueso Alveolar/diagnóstico por imagen , Sulfato de Calcio , Humanos , Proyectos Piloto , Extracción Dental , Alveolo Dental/diagnóstico por imagen , Alveolo Dental/cirugía
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