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1.
Clin Oral Investig ; 26(2): 1229-1239, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34327588

RESUMEN

OBJECTIVES: This study aimed to investigate the mandibular canal of ramus and design a suitable osteotomy line for intraoral vertical ramus osteotomy (IVRO) using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Ninety patients were classified into class I, II, and III skeletal pattern groups. When extended from the horizontal base plane (0 mm, mandibular foramen [MF]), with a 2-mm section interval, to 10 mm above and 10 mm below the MF, the following landmarks were identified: external oblique ridge (EOR), posterior border of the ramus (PBR), and posterior lateral cortex of ramus (PLC): IVRO osteotomy point. RESULTS: In the base plane (0-mm plane), the EOR-PBR distance of class III (34.78 mm) and the IOR-PBR distance of class II (32.72 mm) were significantly higher than those of class I (32.95 mm and 30.03 mm). Compared to the EOR-PLC distance, the designed osteotomy point (two-thirds EOR-PBR length) has a 3.49-mm safe zone at the base plane and ranging from 0.89 mm (+ 10-mm plane) to 8.37 mm (- 10-mm plane). CONCLUSIONS: The position at two-thirds EOR-PBR length (anteroposterior diameter of the ramus) can serve as a reference distance for the IVRO osteotomy position. CLINICAL RELEVANCE: Mandibular setback operations for treating mandibular prognathism mainly include sagittal split ramus osteotomy (SSRO) and IVRO. IVRO has a markedly lower incidence of postoperative lower lip paraesthesia than SSRO. Our design presented a reference point for identification during IVRO, to prevent damage to the inferior alveolar neurovascular bundle.


Asunto(s)
Maloclusión de Angle Clase III , Prognatismo , Tomografía Computarizada de Haz Cónico , Humanos , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Osteotomía Sagital de Rama Mandibular , Prognatismo/diagnóstico por imagen , Prognatismo/cirugía
2.
J Formos Med Assoc ; 121(12): 2593-2600, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35843789

RESUMEN

BACKGROUND/PURPOSE: Postoperative skeletal relapse is the most important issue in patients undergoing orthognathic surgery. This study aimed to investigate clinical skeletal relapse (≥2 mm) after mandibular setback surgery (intraoral vertical ramus osteotomy: IVRO) using receiver operating characteristic curve (ROC curve) analysis. METHODS: Serial cephalograms of 40 patients with mandibular prognathism were obtained at different time points: (1) before surgery (T1), (2) immediately after surgery (T2), and (3) at least with a 2-year follow-up postoperatively (T3). The menton (Me) was used as the landmark for measuring the amount of mandibular setback and postoperative skeletal relapse. Postoperative stability (T32) was divided into groups A and B by skeletal relapse ≥2 mm and <2 mm, respectively. The area under the ROC curve (AUC) was used to determine the cut-off point for mandibular setback. RESULTS: At the immediate surgical setback (T21), the amount of setback in group A (15.55 mm) was significantly larger than in group B (10.97 mm). Group A (T32) showed a significant relapse (4.07 mm), while group B showed a significant posterior drift (1.23 mm). The amount of setback had the highest AUC area (0.788). The cut-off point was 14.1 mm (T21) that would lead to a clinical relapse of 2 mm (T32). CONCLUSION: In IVRO, the postoperative mandibular positions reveal posterior drift and anterior displacement (relapse). The experience of clinical observation and patient perception of postoperative skeletal relapse was ≥2 mm. In the ROC curve analysis, the cut-off point of setback was 14.1 mm.


Asunto(s)
Maloclusión de Angle Clase III , Procedimientos Quirúrgicos Ortognáticos , Prognatismo , Humanos , Prognatismo/cirugía , Curva ROC , Cefalometría , Mandíbula/cirugía , Recurrencia , Estudios de Seguimiento
3.
J Formos Med Assoc ; 121(1 Pt 2): 434-438, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33966940

RESUMEN

Malaria is an infectious disease caused by Plasmodium parasites that are mainly transmitted through the bites of infected female Anopheles mosquitoes. The average annual number of malaria cases was less than ten in Taiwan in the last five years. Most of the cases were caused by Plasmodium vivax and Plasmodium falciparum, and were primarily diagnosed in travelers who returned from Southeast Asia and Africa. Here, we report the first case of Plasmodium ovale infection within five years that was confirmed by peripheral blood smear examination and molecular identification in a 25-year-old Asian female patient who returned from Uganda.


Asunto(s)
Malaria , Plasmodium ovale , Adulto , África Oriental , Femenino , Humanos , Malaria/diagnóstico , Malaria/tratamiento farmacológico , Plasmodium ovale/genética , Taiwán
4.
J Formos Med Assoc ; 120(1 Pt 3): 697-704, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32753286

RESUMEN

BACKGROUND/PURPOSE: The neurosensory disturbance is a common complication following sagittal split ramus osteotomy (SSRO) whereas the shortest buccal bone marrow (SBM) is an important risk factor. The present study aimed to investigate the relationship between the occurrence rates of SBM among three skeletal patterns. METHODS: The cone-beam computed tomography (CBCT) images of 90 participants were divided into skeletal Class I, II, and III. There were six horizontal planes separated apart by a 2 mm interval; it started with plane 0 (original intact mandibular canal) to plane 5 which was 10 mm below. The data of SBM were divided into two groups (SBM ≥ 1 mm and SBM < 1 mm). With an SBM value < 1 mm, we defined a high occurrence rate of postoperative neurosensory abnormality or unfavorable split. RESULTS: The Class III patients had the smallest SBM value (1.31-1.75 mm) whereas the Class II patients had the largest SBM value (1.57-2.09 mm). For the Class III patients, the highest and lowest occurrence rates of SBM were 56.5% and 43.5% respectively. For the Class II patients, the highest and lowest occurrence rates of SBM were 37.1% and 17.7% respectively. The patients with Class III malocclusion had higher occurrence rates of SBM than the patients with Class II malocclusion. CONCLUSION: Class III had a significantly higher occurrence of probability (SBM < 1 mm) than Class II. Therefore, patients with Class III were more likely to experience postoperative neurosensory abnormalities and unfavorable split than patients with Class II.


Asunto(s)
Osteotomía Sagital de Rama Mandibular , Médula Ósea/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Humanos , Maloclusión de Angle Clase III , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía
5.
BMC Med Imaging ; 20(1): 39, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32293310

RESUMEN

BACKGROUND: In the literature, attempts are seldom made to quantify spatial limitation during mandibular arch distalization. This study aimed to investigate the spatial limitations associated with cortical contact with the mandibular second molar during mandibular arch distalization. METHODS: The study population included 67 individuals who had undergone cone beam computed tomography (CBCT) (34 male and 33 female; mean age: 23.9 ± 2.72 years). The total ridge width, alveolar housing width, and root width were measured to evaluate the buccolingual limit. The space distal to the molar root represented the mesiodistal limit. The influence of sex, right versus left side, root-contact condition, malocclusion category, and presence of wisdom teeth were evaluated. RESULTS: The rate of cortical contact was 49.3% before any orthodontic movement. No significant differences were observed in the alveolar width according to sex (male vs female), side assessed (right vs left), wisdom teeth (present vs absent), or malocclusion category. The ridge width and the alveolar width were smaller in the contact group than in the non-contact group (P < 0.01). The group with wisdom teeth showed a larger available distalization distance, but a significant difference was observed only near the alveolar crest. CONCLUSIONS: Both ridge width and available distalization distance were limiting factors for mandibular teeth distalization. For cases in which whole-arch distalization is planned, CBCT is recommended before treatment, especially for non-extraction treatment. This approach ensures safe and predictable tooth movement.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Maloclusión/diagnóstico por imagen , Mandíbula/diagnóstico por imagen , Tercer Molar/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Ortodoncia Correctiva , Estudios Retrospectivos , Adulto Joven
6.
Odontology ; 108(3): 503-510, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31802301

RESUMEN

The aim of present study was to investigate the critical risk factor (age 30: peak bone mass) to evaluate the success of orthodontic implants. A total of 426 orthodontic implants were placed in 270 patients as orthodontic anchorages. Data were analyzed according to patient's characteristics, location of placement, implant categories, and orthodontic force. The young patients were the age ≤ 30 years and the older patients were the age > 30 years. Statistical analysis was performed and a p value < 0.05 was considered to indicate statistical significance. The Chi-square or Fisher exact test was used depending on sample sizes. The null hypothesis was no statistically significant correlation between age ≤ 30 years and age > 30 years. The overall success rate (with and without predrill) was 89.2%. The success rate of orthodontic implants was significantly larger in younger patients (89.9%) than in older patients (76.1%). Recognizing age-related factor in the success rates, older patient (> 30 years) were significant lower than young patients (≤ 30 years) in the gender (female and male), malocclusion (Class II), facial pattern (ortho and hyperdivergent), location (infrazygomatic crest), jaw (maxilla), side (right), material (titanium and stainless), length (9 mm and 10 mm), diameter (2 mm), load (< 3 weeks), and force (intrusion). Therefore, the null hypothesis was rejected. Age 30 is a cutoff point to achieve the success of orthodontic implants. The success rates of older patients (age > 30 years) were significant lower than young patients (age ≤ 30 years), especially in female.


Asunto(s)
Implantes Dentales , Maloclusión , Métodos de Anclaje en Ortodoncia , Anciano , Densidad Ósea , Femenino , Humanos , Masculino , Maxilar
7.
J Formos Med Assoc ; 117(7): 632-639, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28911792

RESUMEN

BACKGROUND/PURPOSE: Patients are always concerned about their postoperative appearance before surgery for facial deformity correction. The present study investigated the facial profile and frontal changes following two-jaw surgery. METHODS: Forty patients who underwent two-jaw surgery were divided by the amount of mandibular setback (group I: ≤8 mm and group II: >8 mm). Cephalometric radiograms (lateral and frontal) were collected and analyzed at three intervals: preoperatively (T1), immediately postoperatively (T2), and final follow-up (T3). The following points were identified: cheek points (C1-C5), pronasale (Prn, tip of the nose), anterior nasal spine (ANS), subnasal (Sn), point A, labrale superius (Ls), incision superius (Is), labrale inferius (Li), incision inferius (Ii), point B, labiomental sulcus (Si), pogonion (Pog), soft tissue pogonion (PogS), ramus point (RP), and gonion (Go). The immediate postoperative changes (T21), final postoperative changes (T32), and final stability (T31) were calculated and analyzed. RESULTS: In T31, the cheek line showed significant advancements of 2.3 mm (group I) and 1.6 mm (group II). The soft:hard tissue ratios were significantly correlated: Prn:ANS (0.37:1), Prn:A (0.39:1), Sn:A (0.85:1), C3:A (0.82:1), Ls:Is (0.92:1), Li:Ii (0.91:1), Si:B (0.88:1), and PogS:Pog (group I, 0.78:1 and group II, 0.93:1). The intercondylion and intergonial widths of group II (T31) significantly increased 1.8 and 4 mm, respectively. Regarding the postoperative skeletal stability (T32), group I showed significant correlations between amounts of mandibular setback, but group II did not. CONCLUSION: In the facial profile, the cheek line showed significant advancement postoperatively. The frontal mandibular transverse dimensions were significantly increased.


Asunto(s)
Cara/anatomía & histología , Mandíbula/cirugía , Osteotomía , Prognatismo/cirugía , Adulto , Cefalometría , Femenino , Estudios de Seguimiento , Humanos , Masculino , Mandíbula/anatomía & histología , Maxilar/anatomía & histología , Radiografía , Recurrencia , Taiwán
8.
Implant Dent ; 27(3): 288-293, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29781832

RESUMEN

PURPOSE: The aim of this study was to evaluate the mechanical strengths in 5 different designs of orthodontic microimplants by analyzing their configuration of structure. MATERIALS AND METHODS: Thirty microimplants of 5 types (diameter 1.5 mm: type A, B, and C; diameter 1.3 mm: type D and E) were assessed. All microimplants were manually driven into the artificial bones at a 7-mm depth. The anchor area (AA), gripping area (GA), insertion torque (IT), Periotest value (PTV), and pullout strength (PS) were measured. Intergroup and intragroup comparisons were used to detect their significant differences. RESULTS: In the intergroup comparison, type D had a least IT (4.5 Ncm). In the PTV analysis, type B had the largest AA (7.76 mm) and its PTV (1.6) was significantly least than the others. In the PS test, type C had the largest GA (2.40 mm) and its PS was the largest. Intragroup comparisons (IT and PS), type A, and type E presented positively significant correlation. GA revealed positive with PS, and AA showed reverse tendency with PTV. CONCLUSION: The more AA of microimplants, the more stable they are. The more GA of microimplants, the more PS they are. Therefore, type C was better than the others because it had the largest GA and second largest AA.


Asunto(s)
Implantes Dentales , Métodos de Anclaje en Ortodoncia , Diseño de Aparato Ortodóncico , Remoción de Dispositivos , Ensayo de Materiales , Acero Inoxidable , Estrés Mecánico , Titanio , Torque
9.
Implant Dent ; 26(4): 553-558, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28350585

RESUMEN

PURPOSE: The aim of this study was to evaluate the pullout strength of 3 different orthodontic mini implants. MATERIALS AND METHODS: Twenty-seven mini implants (diameter: 2 mm, length: 7 mm) were implanted into artificial bone (Sawbones; Pacific Research Laboratories Inc.) at depths of 3, 4, and 5 mm. The insertion torque (IT), resonance frequency (RF), pullout strength (PS), and anchor length (AL) were measured. One-way analysis of variance with Tukey honest significant difference (HSD) postcomparison were used to detect intergroup differences. The null hypothesis was that IT, RF, and PS would significantly correlate in the same brand. RESULTS: In the implantation depths (ID) (5 and 4 mm), IT of Types C (16.67 and 14.33 N·cm) and Type B (14 and 13.33 N·cm) were significantly higher than Type A (10.33 and 9.33 N·cm). Type A had a largest AL and PS at the IDs (5 and 4 mm). In the IDs (3 mm), PS was no different. Type C had no correlation among the RF, IT, and PS. Therefore, null hypothesis was rejected. CONCLUSION: AL exerted crucial effects on the PS of the mini implants.


Asunto(s)
Implantes Dentales , Métodos de Anclaje en Ortodoncia , Diseño de Aparato Ortodóncico , Fenómenos Biomecánicos , Materiales Biomiméticos , Análisis del Estrés Dental , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Estrés Mecánico , Propiedades de Superficie
10.
Odontology ; 102(1): 81-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23377841

RESUMEN

This study tested the hypothesis that developmental heterogeneity in cranial base morphology increases the prevalence of Class III malocclusion and mandibular prognathism in Asians. Thin-plate spline (TPS) graphical analysis of lateral cephalometric radiographs of the cranial base and the upper midface configuration were compared between a European-American group (24 females and 31 males) and four Asian ethnic groups (100 Chinese, 100 Japanese, 100 Korean and 100 Taiwanese; 50 females and 50 males per group) of young adults with clinically acceptable occlusion and facial profiles. Procrustes analysis was performed to identify statistically significant differences in each configuration of landmarks (P < 0.001). The TPS graphical analysis revealed that the greatest differences of Asians were the horizontal compression and vertical expansion in the anterior portion of the cranial base and upper midface region. The most posterior cranial base region also showed horizontal compression between the basion and Bolton point, with forward displacement of the articulare. Facial flatness and anterior displacement of the temporomandibular joint, resulting from a relative retrusion of the nasomaxillary complex and a relative forward position of the mandible were also noted. These features that tend to cause a prognathic mandible and/or retruded midface indicate a morphologic predisposition of Asian populations for Class III malocclusion.


Asunto(s)
Pueblo Asiatico , Base del Cráneo/anatomía & histología , China/etnología , Femenino , Humanos , Japón/etnología , Masculino , República de Corea/etnología , Taiwán/etnología
11.
Artículo en Inglés | MEDLINE | ID: mdl-24964647

RESUMEN

Cryptosporidiosis is a zoonotic disease caused by the protozoan parasite Cryptosporidium. A total of 436 horse fecal samples were collected from 19 farms, and acid-fast staining method was used for primary screening. Cryptosporidium oocysts were found in 161 samples, among which 33 positive sample were selected for nested PCR, restriction fragment length polymorphism analysis and DNA sequencing of 18 S rDNA, showing 31 samples to be bovine C. parvum and 2 C. felis. The methods employed in this study should be useful as tools to identify cryptosporidiosis genotypes and species of livestock.


Asunto(s)
Criptosporidiosis/epidemiología , Criptosporidiosis/parasitología , Criptosporidiosis/veterinaria , Cryptosporidium/aislamiento & purificación , Heces/parasitología , Caballos/parasitología , Animales , Cryptosporidium/genética , Reacción en Cadena de la Polimerasa , Prevalencia , Análisis de Secuencia de ADN , Taiwán/epidemiología
12.
J Dent Sci ; 19(1): 364-376, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38303855

RESUMEN

Background/purpose: In comparing the cranial base's size, most cephalometric studies focused on the length and angle in the anteroposterior direction. However, investigating the anterior, middle, and posterior cranial base's transverse dimensions is challenging. This study aimed to investigate the transverse dimensions of the cranial base in different craniofacial skeletal patterns and sexes using cone-beam computed tomography (CBCT). Materials and methods: A total of 210 adults (105 males and 105 females), including three different skeletal relationships, were included in the study. The cranial base dimensions were measured on a three-dimensional image structure rendered by CBCT. Statistical methods included the Kappa statistic for analysis of consistency and reproducibility and the independent t-test for differences in cranial base dimensions between sexes. A general linear model (GLM) was used to compare the transverse size of the cranial base among skeletal Class I, II, and III groups. The Pearson correlation coefficient explored the correlation among the cranial base dimensions. Results: The cranial base dimensions did not differ significantly between skeletal Class I, II, and III. The more prominent cranial base size was found in males than females, except for the crista galli length (CGL) and cribriform ethmoid plate width (CEPW). The cranial base dimensions did not differ significantly between different skeletal relationships. Most dimensions have significant correlations in the middle and the posterior cranial base. Conclusion: The cranial base's transverse dimensions in Taiwanese adults show no significant differences between craniofacial skeletal relationships. In the middle and posterior cranial base, transverse measurements reveal significant sexual dimorphism.

13.
J Dent Sci ; 19(3): 1443-1451, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39035289

RESUMEN

Background/purpose: The extent of three-dimensional soft tissue changes in patients with varied facial skeletal patterns following mandibular setback surgery remains unclear. In this study, we aimed to investigate the postoperative changes in soft tissue chin thickness among mandibular prognathism patients, focusing on those presenting different divergence patterns, such as hyperdivergent and normodivergent patients. Materials and methods: Cone-beam computed tomography images were obtained from 56 skeletal Class III patients who underwent only mandibular setback. Based on vertical craniofacial skeletal relationship, patients were divided into normodivergent group (27°37°) group. The three-dimensional displacements of Infradentale (Id), B point (B), and Pogonion (Pog), the soft tissue thickness of Id-Li (Labrale inferius), B-B' (soft tissue B point), and Pog-Pog' (soft tissue Pog point) were measured. Factors influencing the change in soft tissue thickness were investigated. Results: Preoperative B-B' and Pog-Pog' thickness were significantly thinner in the hyperdivergent group than normodivergent group. Postoperative changes in B-B' and Pog-Pog' thickness were significantly larger in the hyperdivergent group than normodivergent group. A significant correlation was found between soft tissue thickness change (B-B' and Pog-Pog') and the preoperative soft tissue thickness and superior movement (B and Pog). Conclusion: Hyperdivergent patients with skeletal class III have thinner preoperative soft tissue thickness (B-B' and Pog-Pog') than normodivergent patients in the preoperation. Postoperative changes in B-B' and Pog-Pog' thickness were significantly larger in the hyperdivergent group than normodivergent group. Postoperative superior movement of B and Pog correlated with postoperative change of soft tissue thickness.

14.
J Formos Med Assoc ; 112(12): 801-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24331110

RESUMEN

This report presents a case of a 12-year-old girl with maxillary deficiency, mandibular prognathism, and facial asymmetry, undergoing growth hormone (GH) therapy due to idiopathic short stature. Children of short stature with or without GH deficiency have a deviating craniofacial morphology with overall smaller dimensions; facial retrognathism, especially mandibular retrognathism; and increased facial convexity. However, a complete opposite craniofacial pattern was presented in our case of a skeletal Class III girl with idiopathic short stature. The orthodontic treatment goal was to inhibit or change the direction of mandibular growth and stimulate the maxillary growth of the girl during a course of GH therapy. Maxillary protraction and mandibular retraction were achieved using occipitomental anchorage (OMA) orthopedic appliance in the first stage of treatment. In the second stage, the patient was treated with a fixed orthodontic appliance using a modified multiple-loop edgewise archwire technique of asymmetric mechanics and an active retainer of vertical chin-cup. The treatment led to an acceptable facial profile and obvious facial asymmetry improvement. Class I dental occlusion and coincident dental midline were also achieved. A 3½-year follow-up of the girl at age 18 showed a stable result of the orthodontic and dentofacial orthopedic treatment. Our case shows that the OMA orthopedic appliance of maxillary protraction combined with mandibular retraction is effective for correcting skeletal Class III malocclusion with midface deficiency and mandibular prognathism in growing children with idiopathic short stature undergoing GH therapy.


Asunto(s)
Enanismo Hipofisario/tratamiento farmacológico , Hormona del Crecimiento/uso terapéutico , Ortodoncia Correctiva/métodos , Prognatismo/terapia , Adolescente , Niño , Asimetría Facial/complicaciones , Femenino , Humanos , Maloclusión de Angle Clase III
15.
Artículo en Inglés | MEDLINE | ID: mdl-23682432

RESUMEN

Cryptosporidium, a protozoan pathogen that causes cryptosporidiosis has emerged as an important source of diarrheal illness among humans and animals. The current routine laboratory technique used for Cryptosporidium diagnosis is light microscopy with acid-fast staining but the technique has low efficiency and sensitivity for species-specific identification. Single PCR to amplify a 220 bp fragment of 18 S ribosomal DNA of C. parvum and C. hominis was developed. The restriction enzymes, TaqI and VspI, were used to distinguish between amplicons of human and bovine C. parvum genotype. Water samples, collected from Lo-Na, Ton-Pu, Ho-Ping, and Jen-Ai, Taiwan contained only bovine C. parvum genotype whereas in the Ton-Pu and Jen-Ai samples C. hominis was also present. Thus, the used of PCR-RFLP allowed successful identification of Cryptosporidium in water samples and differentiation between human and bovine species.


Asunto(s)
Cryptosporidium/genética , Agua Dulce/parasitología , Secuencia de Aminoácidos , Animales , Bovinos , Cryptosporidium/aislamiento & purificación , Cryptosporidium parvum/genética , Cryptosporidium parvum/aislamiento & purificación , Enzimas de Restricción del ADN , Genes Protozoarios , Genotipo , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Taiwán
16.
J Dent Sci ; 18(3): 1031-1041, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37404629

RESUMEN

Background/purpose: Facial asymmetry is a common dentofacial deformity especially in skeletal Class III jaw relation. The purpose of this study was to evaluate the condylefossa relationship of Taiwanese people in skeletal Class III jaw relation with or without facial asymmetry by CBCT image. Materials and methods: CBCT images were collected from Kaohsiung Medical University Hospital and then divided into symmetric Class III group (Menton [Mn] deviation â‰¦ 4 mm) and asymmetric Class III group (Menton [Mn] deviation > 4 mm). Maxilla deviation, upper and lower dental midline deviation, joint space, condylar axial angle and condylar volume was measured. Independent t test was used for comparison between groups, and paired t test was applied for comparison between both condyles within each group. The Pearson correlation coefficient was used to analyze the correlation between skeletal midline deviations and joint morphology. Results: No significant difference was found in joint space between groups or between sides within each group, but we can find a significant difference in axial condylar angle easurement which was greater on the non-deviation side of condyle. Significant lesser condylar volume was also found on the deviation side in asymmetric group. There had a significant positive correlation between Mn point deviation, geometric center difference and condylar volume ratio. Conclusion: These results demonstrated that in the side with greater mandibular growth potential, the axis rotation in axial plane would be greater. In the side with lesser mandibular growth potential, the total condyle volume would be lesser, even though with large variation.

17.
J Dent Sci ; 18(1): 175-183, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36643236

RESUMEN

Background/purpose: Among the craniofacial structures, the mandible is the only bony structure with movable joints. Each part (including condyle process, coronoid process, and ramus) of mandible would interaction with the muscles and proceed different osteogenesis progress. The objective of this study was to evaluate the mandibles with symmetric and asymmetric skeletal Class III jaw relations by quantifying differences in the condyle process, coronoid process and ramus on CBCT (Cone-beam computer tomography) images. Our hypothesis was that CBCT would reveal no voluminal differences between deviated and non-deviated mandibular segments in asymmetric skeletal Class III. Materials and methods: CBCT imagines were collected from dental department, KMUH and then divided into symmetric Class III group (Menton deviation < 4mm) and asymmetric Class III group (Menton deviation≧4mm). The mandibular structure would be segmented to ramus, condylar and coronoid process. Each volume was measured. Independent t test was used for comparison between groups, and paired t test was applied for comparison between both segmented parts within each group. Results: Significant differences between deviation and non-deviation sides in the asymmetric group were found in condylar and ramus segments for volumetric quantitative measurements. There has no significant difference in ramus parts between groups. Significant greater condylar volume was found in non-deviation side of asymmetric group. Conclusion: The results demonstrated that in the side with greater mandible growth potential, the condylar and the ramus volume would be greater as well. CBCT is a useful and accurate modality for quantification and evaluation of mandibular asymmetry.

18.
Bull Environ Contam Toxicol ; 89(2): 240-4, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22617948

RESUMEN

The purpose of this animal study was to investigate the influence of maternal lead exposure during pregnancy and lactation on molar development in the offspring. Scanning electron microscopy revealed no significant differences in the molar morphology among the groups. However, in all the experimental groups, deep, wide cracks were found in the occlusal enamel. Further, the experimental groups had smaller molar diameters than the control group, lead exposure during lactation had a greater influence on the molar size in the offspring, and the groups with the higher dose of lead exposure during pregnancy and lactation had significantly smaller molar sizes than the groups that received the lower dose. The mesiodistal and buccolingual diameters of molars were measured as 3.10 ± 0.07 and 1.95 ± 0.04 mm for control group, 2.97 ± 0.08 and 1.94 ± 0.01 mm for lactation group of low dose, 2.96 ± 0.05 and 1.84 ± 0.02 mm for lactation group of high dose, 3.09 ± 0.06 and 1.94 ± 0.04 mm for pregnancy group of low dose, and 3.02 ± 0.06 and 1.85 ± 0.06 mm for pregnancy group of high dose, respectively.


Asunto(s)
Esmalte Dental/efectos de los fármacos , Lactancia , Plomo/toxicidad , Exposición Materna/efectos adversos , Diente Molar/efectos de los fármacos , Animales , Esmalte Dental/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Agua Potable/química , Femenino , Microscopía Electrónica de Rastreo , Diente Molar/crecimiento & desarrollo , Embarazo , Efectos Tardíos de la Exposición Prenatal , Ratas , Ratas Sprague-Dawley
19.
Parasitol Int ; 88: 102553, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35124287

RESUMEN

Cryptosporidium spp. is a group of protozoans that cause diarrheal disease in both humans and animals. In Taiwan, very little information is available about the epidemiology of Cryptosporidium spp. in domesticated animals, especially in Eastern Taiwan where agriculture is one of the main industries. Therefore, this study aimed to investigate the occurrence of Cryptosporidium spp. in livestock in Hualien Country of Eastern Taiwan and identify their genotypes. Excrements from dogs (n = 81), cattle (n = 156), and pigs (n = 142) were randomly collected from different pastures or farm in Hualien Country. Microscopic examination and nested PCR were performed on all samples and both showed identical results, with 4.94% (4/81) of dogs, 24.36% (38/156) of cattle, and 16.20% (23/142) of pigs being infected with Cryptosporidium species. Positive samples were then sequenced and analyzed. DNA sequencing revealed that all four positive samples isolated from dogs were Cryptosporidium canis (C. canis); 38 positive samples from cattle were identified as C. bovis (8/38), C. canis (1/38), C. ryanae (4/38), and C. scrofarum (25/38); and 22 positive samples isolated from pigs were identified as C. scrofarum while one was identified as C. suis. In addition, the infective rates of animals from indoor farms (57.14% of all positive samples) are much higher than the rates from pastures. This study provided evidence of the occurrence of Cryptosporidium spp. in Hualien country, and farming conditions largely affect their infection rates. Therefore, precautions should be made to control Cryptosporidium spp. transmission.


Asunto(s)
Enfermedades de los Bovinos , Criptosporidiosis , Cryptosporidium , Enfermedades de los Porcinos , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Criptosporidiosis/epidemiología , Cryptosporidium/genética , Perros , Heces , Genotipo , Ganado , Prevalencia , Porcinos , Enfermedades de los Porcinos/epidemiología , Taiwán/epidemiología
20.
J Pers Med ; 12(3)2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35330507

RESUMEN

(1) Background: This study explored the effects of modified anterior maxillary subapical osteotomy (AMSO) on facial profile changes in patients with bimaxillary protrusion. (2) Methods: Cephalograms of patients were collected preoperatively and over 2 months postoperatively. The following landmarks were recorded: pronasale (Prn), subnasale (Sn), labrale superius (Ls), anterior nasal spine (ANS), and incisor superius (Is). The following distances and angles were measured: ANS-Prn, ANS-Sn, ANS-Ls, Is-Sn, Is-Ls, SNA angle, and nasolabial (NLA) angle. (3) Results: Is and ANS were significantly retracted by 7.3 and 2.3 mm, respectively. Soft tissue landmarks (Prn, Sn, and Ls) were significantly retracted (1.2, 1.6, 4.4 mm, respectively). Postoperative changes in soft/hard tissue ratios were 0.54, 0.72, 0.31, and 0.60 for Prn/ANS, Sn/ANS, ANS/Is, and Ls/Is, respectively. The NLA angle was increased significantly by 7.1°. (4) Conclusions: The horizontal soft/hard tissue ratios of Sn/Is, ANS/Is, and Ls/Is were 0.22, 0.31, and 0.60, respectively. The NLA angle was increased significantly by 7.1°. The modified AMSO provides an increased blood supply, allows for direct vision, and results in fewer complications than other AMSO methods.

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