1.The malaris muscle concept reconsidered
Natnicha KAMPAN ; Keiichi AKITA ; Pasuk MAHAKKANUKRAUH
Anatomy & Cell Biology 2019;52(2):134-139
The malaris muscle has long been described as one of the facial muscles. Numerous studies have attempted to define and examine the malaris muscle owing to its clinical implications related to the facial aesthetic concept. In the anatomical context, however, the concept of the malaris muscle remains ambiguous. This review article proposes a reconsideration of the malaris muscle. The article focuses on the anatomical concept of the malaris muscle from previous studies to the current studies as well as the conceptual changes in the malaris muscle. To improve understanding of the role of the malaris muscle in the facial aesthetic aspects, here the article reviews the role of the malaris muscle in facial aging appearance and discusses the practical clinical applications surrounding this aging gradation.
Aging
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Facial Muscles
2.Effects of the cone-beam computed tomography protocol on the accuracy and image quality of root surface area measurements: An in vitro study
Chanikarn INTARASUKSANTI ; Sangsom PRAPAYASATOK ; Natnicha KAMPAN ; Supassara SIRABANCHONGKRAN ; Pasuk MAHAKKANUKRAUH ; Thanapat SASTRARUJI ; Pathawee KHONGKHUNTHIAN ; Kachaphol KUHARATTANACHAI ; Kanich TRIPUWABHRUT
Imaging Science in Dentistry 2023;53(4):325-333
Purpose:
The objective of this study was to evaluate and compare the accuracy and image quality of root surface area (RSA) measurements obtained with various cone-beam computed tomography (CBCT) protocols, relative to the gold standard of micro-computed tomography (CT), in an in vitro setting.
Materials and Methods:
Four dry human skulls were scanned using 8 different protocols, with voxel sizes of 0.15 mm, 0.3 mm, and 0.4 mm. Three-dimensional models of the selected teeth were constructed using CBCT and microCT protocols, and the RSA was automatically measured by the image-processing software. The absolute difference in the percentage of the RSA (%ΔRSA) was calculated and compared across the 8 CBCT protocols using repeatedmeasures analysis of variance. Finally, image quality scores of the RSA measurements were computed and reported in terms of percent distribution.
Results:
No significant differences were observed in the %ΔRSA across the 8 protocols (P>0.05). The deviation in %ΔRSA ranged from 1.51% to 4.30%, with an increase corresponding to voxel size. As the voxel size increased, the image quality deteriorated. This decline in quality was particularly noticeable at the apical level of the root, where the distribution of poorer scores was most concentrated.
Conclusion
Relative to CBCT protocols with voxel sizes of 0.15 mm and 0.3 mm, the protocols with a voxel size of 0.4 mm demonstrated inferior image quality at the apical levels. In spite of this, no significant discrepancies were observed in RSA measurements across the different CBCT protocols.