Biomedical subjects

V Tangugsorn

Publications and source records attributed to V Tangugsorn.

8 recordsLinked to original sources

PubMed2001

Obstructive sleep apnea: a canonical correlation of cephalometric and selected demographic variables in obese and nonobese patients.

One hundred male obstructive sleep apnea (OSA) patients were classified into 2 groups on the basis of body mass index (BMI): 43 nonobese (BMI < 30 kg/m2) and 57 obese (BMI > or = 30 kg/m2) patients. A comprehensive cephalometric analysis with a multivariate statistical method was performed in order to define the different principal components (PCs) of cervico-craniofacial skeletal and upper airway soft tissue morphology in each group and how they contributed to selected elements of the patient demographic data, ie, apnea-hypopnea index (AHI), nocturnal oxyhemoglobin saturation, and BMI. Thirty cephalometric variables of cervico-craniofacial skeletal morphology were reduced to 8 PCs describing 84.4% and 85.4% of the total variance in obese and nonobese OSA patients, respectively. Sixteen cephalometric variables of hyoid bone position and head posture were reduced to 4 PCs describing 84.4% and 85.9% of the total variance in obese and nonobese OSA patients, respectively. Twenty cephalometric variables of upper airway soft tissue morphology were reduced to 7 PCs describing 89.5% and 84.6% of the total variance in obese and nonobese OSA patients, respectively. For further analysis of PCs, a stepwise multiple regression analysis was chosen. Two dependent variables of interest are the minimal distance of the posterior pharyngeal airway space (PASmin) and AHI. PASmin accounted for 95.3% (obese OSA group) and 74.3% (nonobese OSA group) with 7 PCs and AHI for 46% with 3 PCs in both groups. Three canonical variables and their correspondents with different loadings were established differently for both OSA groups. A canonical correlation successfully clarified the complexity of simultaneous relationship of the relevant variables. These analyses are proved useful to demonstrate the relationship of cervico-craniofacial skeletal and upper airway soft tissue morphology and selected demographic data. This lays down a basis for understanding the complicated pathogenic components of obese and nonobese OSA patients.

Adult↗

PubMed2000

Obstructive sleep apnoea: multiple comparisons of cephalometric variables of obese and non-obese patients.

BACKGROUND: Pathogenesis of obstructive sleep apnoea (OSA) is complex and not yet fully understood. Several factors contribute to OSA severity. Obesity is believed to play an important role. Nevertheless, not all OSA patients are obese. Therefore, the different features that cause nocturnal upper airway obstruction in obese and non-obese OSA patients could be expected. PURPOSE: To investigate the different components of cervico-craniofacial skeletal and upper airway soft tissue morphology among obese OSA, non-obese OSA patients and the controls. PATIENTS: One hundred male OSA patients were classified into two groups on the basis of body mass index (BMI) as obese (BMI > or = 30 kg/m2) and non-obese (BMI < 30 kg/m2). Consequently, 57 obese and 43 non-obese OSA patients were examined and compared with a control group of 36 healthy males. STUDY DESIGN: A comprehensive cephalometric analysis of cervico-craniofacial skeletal and upper airway soft tissue morphology was performed. Sixty-eight cephalometric variables were compared among the three groups by one way analysis of variance with Bonferroni's test. RESULTS: Both OSA groups had aberrations of cervico-craniofacial skeletal as well as upper airway soft tissue morphology when compared with the controls. These anatomic deviations were confined to cervico-craniofacial skeletal structures in the non-obese OSA patients, whereas the obese OSA patients had more abnormalities in the upper airway soft tissue morphology, head posture and position of the hyoid bone. CONCLUSION: The findings imply that there should be different treatment regimens for the two subgroups of OSA patients. Cephalometric analysis together with various considerations of BMI is highly recommended as one of the most important tools in diagnosis and treatment planning for OSA patients.

Adult↗

PubMed2000

Obstructive sleep apnea (OSA): a cephalometric analysis of severe and non-severe OSA patients. Part II: A predictive discriminant function analysis.

One hundred male obstructive sleep apnea (OSA) patients were classified into 2 groups on the basis of apnea-hypopnea index (AHI) as severe (AHI > or = 50) and non-severe (AHI < 50). A comprehensive cephalometric analysis of cervicocraniofacial skeletal and upper airway soft tissue morphology was performed in 51 non-severe and 49 severe OSA patients. In addition, a multivariate statistical method (principal component, analysis and predictive discriminant analysis) was performed to identify the components that could correctly differentiate the severe from the non-severe OSA patients. Eight principal components (PCs) of cervicocraniofacial skeletal morphology, 4 PCs of hyoid bone position and head posture, and 7 PCs of upper airway soft tissue morphology, together with the selected demographic variables, were deduced to formulate a linear canonical discriminant function. The equation of a 9-variable model was generated as follows: PDF score = 4.127 - 0.144 (Body Mass Index) - 0.376 (PC1.1) + 0.311 (PC1.4) + 0.214 (PC1.5) + 0.075 (PC 2.1) - 1.309 (PC2.3) + 0.708 (PC3.2) - 0.059 (PC3.3) + 0.609 (PC3.6). The cutoff score was -0.03899. The overall rate of correct classification was 83%. The results showed that Body Mass Index and 8 other PCs contributed significantly to the OSA severity. These analyses are proven to be a useful adjunctive diagnostic tool to select optimal treatment regimens for OSA patients with varying degrees of severity.

Aged↗

PubMed2000

Obstructive sleep apnea (OSA): a cephalometric analysis of severe and non-severe OSA patients. Part I: Multiple comparison of cephalometric variables.

One hundred male obstructive sleep apnea (OSA) patients were classified into 2 groups, on the basis of Apnea-Hypopnea Index (AHI), as severe (AHI > or = 50) and non-severe (AHI < 50). A comprehensive cephalometric analysis of cervicocraniofacial skeletal morphology and upper airway soft tissue morphology was performed in 51 non-severe OSA patients, 49 severe OSA patients, and 36 controls with the purpose of examining the different features among these 3 groups. Sixty-eight cephalometric variables were compared among these 3 groups by 1-way analysis of variance with post hoc Bonferroni test. The results showed that both OSA groups had aberrations of cervicocraniofacial skeletal morphology and upper airway soft tissue morphology versus the controls. Severe OSA patients demonstrated increased maxillo-mandibular retrognathism, with a high mandibular plane angle resulting from increased anterior lower facial height and decreased posterior lower facial height, versus the non-severe OSA group. The craniocervical extension, forward head posture, inferiorly positioned hyoid bone, and the enlarged and elongated soft palate and upright tongue posture were more exaggerated as well. These findings imply that there should be different treatment regimens for the 2 subgroups of OSA patients to achieve treatment success. Cephalometric analysis is therefore highly recommended to verify the aberrant cervicocraniofacial morphology in severe and non-severe OSA patients.

Adult↗

PubMed1999

Obstructive sleep apnea: a principal component analysis.

A principal component analysis was performed on the cephalometric variables of 100 male obstructive sleep apnea (OSA) patients. Thirty cephalometric variables of cervicocraniofacial skeletal morphology were reduced to 8 principal components (PCs), which described 83.2% of the total variance. Sixteen cephalometric variables of hyoid bone position and head posture were reduced to 4 PCs, which described 85.5% of the total variance. Twenty cephalometric variables of upper airway soft tissue were reduced to 7 PCs, which described 83.7% of the total variance. These PCs described the actual characteristics of the OSA patients examined. For further analysis of PCs, stepwise multiple regression analysis was chosen. Two dependent variables of interest are the minimal distance of posterior pharyngeal airway space (PASmin) and the Apnea-Hypopnea Index (AHI). Seven PCs accounted for 79.4% of the variance of PASmin and 3 PCs accounted for 37.6% of the variance of AHI. Both principal component analysis and multiple regression analysis provide multivariate data analysis that is very useful in sorting out and clarifying the complexity of the interrelated cervicocraniofacial skeletal morphology and upper airway soft tissue in OSA patients.

Adult↗

PubMed1995

Obstructive sleep apnoea: a cephalometric study. Part I. Cervico-craniofacial skeletal morphology.

A comprehensive cephalometric analysis of cervico-craniofacial skeletal morphology in 100 male patients with obstructive sleep apnoea (OSA) and 36 male controls was performed. The significant aberrations in the OSA group feature: (1) shorter dimension of cranial base with slight counter-clockwise rotation and depression of clivus; (2) shorter maxillary length with normal height; (3) maxillo-mandibular retrognathia related to nasion perpendicular plane (N perpendicular FH) despite normal angles of prognathism; (4) 47 per cent of the OSA group had mandibular retrognathia; (5) increased anterior lower facial height and mandibular plane angle; (6) reduced size of bony pharynx; (7) inferiorly positioned hyoid bone at C4-C6 level; (8) deviated head posture with larger cranio-cervical angle. Cephalometric analysis is highly recommended in OSA patients as one of the most important tools in diagnosis and treatment planning.

Adult↗

PubMed1995

Obstructive sleep apnoea: a cephalometric study. Part II. Uvulo-glossopharyngeal morphology.

A comprehensive cephalometric analysis of uvulo-glossopharyngeal morphology in 100 patients with obstructive sleep apnoea (OSA) and 36 controls was performed. The aberrations in OSA patients included: 1. Increased length, thickness, and sagittal area of soft palate (PM-U; SPT; SPA: P < 0.001) with a more upright position (NL/PM-U: P < 0.05) and 15 per cent more pharyngeal area occupation [SPA/(OPA-OA): P < 0.001]. 2. The contact length between the soft palate and the tongue was increased approximately two-fold (CL: P < 0.001). 3. The sagittal area of the tongue was 10 per cent larger (TA: P < 0.001) despite similar length and height and 3 per cent more oral area occupation (TA/OA: P < 0.05). 4. More upright tongue position (VT/FH: P < 0.05) and caudally extended tongue mass (V perpendicular FH: P < 0.05). 5. Decreased sagittal dimensions of nasopharynx (pm-UPW: P < 0.001), velopharynx (U-MPW: P < 0.001) and minimum distance between the base of the tongue and the posterior pharyngeal wall (PASmin: P < 0.001). 6. The residual oropharyngeal area (area not occupied by soft tissues) was 9 per cent less due to larger tongue and soft palate [(TA+SPA)/OPA: P < 0.001]. Cephalometric analysis is highly recommended in OSA patients as one of the most important tools in diagnosis and treatment planning.

Adult↗

PubMed1994

The effect of titanium tetrafluoride (TiF4) application around orthodontic brackets.

In the present in vivo study, the cariostatic potential of a titanium tetrafluoride (TiF4) solution applied topically around orthodontic brackets was investigated with quantitative microradiography. Also characteristics of the TiF4-treated enamel surface were examined with scanning electron microscopy (SEM). Ten pairs of premolars to be extracted for orthodontic treatment were used in the first part of this study. Brackets were bonded on all teeth with an orthodontic adhesive, and 10 randomly selected premolars served as controls, whereas a similar number were treated with 1% TiF4 around brackets for 60 seconds. After 4 weeks with no topical fluoride supplementation, all teeth were extracted and stored for analysis. Results indicated the 1% TIF4 solution reduced lesion depths and total mineral loss, at the bracket periphery, significantly during the 4-week period. The presence of a surface coating was demonstrated by SEM micrographs. It was concluded that TiF4 may provide a high level performance as a prophylactic agent for orthodontic purposes.

Child↗