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Sang Woong Youn - One of the best experts on this subject based on the ideXlab platform.

  • Relation between pH in the Trunk and Face: Truncal pH Can Be Easily Predicted from Facial pH.
    Annals of Dermatology, 2016
    Co-Authors: Sung Ae Kim, Mi Young Chun, Bo Ri Kim, Sang Woong Youn
    Abstract:

    Background: The clinical symptoms of facial and truncal acne differ. Skin surface acidity (pH), which is affected by Sebum Secretions, reflects the different clinical characteristics of the face and trunk. However, no studies have been conducted on truncal Sebum production and skin pH. Objective: We evaluated the differences and relationship between pH values of the face and trunk. We also evaluated the relationship between pH and the quantity of Sebum produced in the trunk. Methods: A total of 35 female patients clinically diagnosed with truncal acne were included. We measured pH on the face and truncal area using the Skin-pH-Meter PH 905 Ⓡ . We measured truncal Sebum Secretions using the Sebumeter SM 815 Ⓡ . Statistical analysis was performed to evaluate the correlations and differences between pH and Sebum. Results: Facial pH was significantly higher than chest and back pH values. The correlation between pH on the trunk and the face was significant. We used linear regression equations to estimate truncal pH using only measured pH from the chin. There was no significant relationship between truncal Sebum Secretion and pH. Conclusion: This was the first study that evaluated the differences and correlations between facial and truncal pH. We found that facial pH can predict truncal pH. In addition, we conclude that differences in pH and Sebum Secretion between the face and trunk are one of the reasons for differences in acne symptom at those sites. (Ann Dermatol 28(2) 216∼221, 2016)

  • Sebum Secretion of the Trunk and the Development of Truncal Acne in Women: Do Truncal Acne and Sebum Affect Each Other?
    Dermatology, 2015
    Co-Authors: Bo Ri Kim, Mi Young Chun, Sung Ae Kim, Sang Woong Youn
    Abstract:

    Background: There are few published data on truncal acne because most studies have focused on facial acne. Aims: The objective of this study was to investigate truncal Sebum Secretion levels in patients with acne vulgaris and to evaluate the relationship between Sebum Secretion and the development of acne lesions. Methods: The Sebum casual levels at five different facial sites and ten truncal sites were measured in 35 Korean females with acne using a Sebumeter®. We performed an analysis of the correlation between Sebum excretion and acne lesion number. Results: We found that all of the truncal sites analyzed had lower Sebum Secretion levels than the facial sites. There was no significant correlation between Sebum Secretion and acne lesions on the trunk. Conclusion: Pathogenic factors other than Sebum may have a predominant role in the development of truncal acne.

  • Sebum Secretion, Skin Type, and pH
    Pathogenesis and Treatment of Acne and Rosacea, 2014
    Co-Authors: Sang Woong Youn
    Abstract:

    Increased facial Sebum Secretion is a common finding during the period when acne commonly develops. Patients with acne frequently think that facial Sebum is the cause of their disease and want to lower or remove it completely. Sebum is always listed as one of the important factors involved in the pathogenesis of acne. Quantitative measurement of Sebum has only recently become possible; currently, we have limited information on the Secretion of Sebum itself. The cosmetic skin type is another common method of assessing facial Sebum Secretion and the skin surface pH (SSPH) is partially affected by facial Sebum Secretion. In this chapter, Sebum Secretion, facial skin type, and SSPH will be reviewed with regard to their prognostic significance for acne.

  • Sebum, acne, skin elasticity, and gender difference – which is the major influencing factor for facial pores?
    Skin research and technology : official journal of International Society for Bioengineering and the Skin (ISBS) [and] International Society for Digita, 2011
    Co-Authors: B. Y. Kim, Jae Woo Choi, Kyoung Chan Park, Sang Woong Youn
    Abstract:

    Background Enlarged facial pores have been esthetic problems and have become a matter of cosmetic concern. Several factors are supposed to be related to the enlargement of facial pores, although scientific evaluations were not performed yet. Objective To assess the correlation between facial pores and possible relating factors such as age, gender, Sebum Secretion, skin elasticity, and the presence of acne, using objective bioengineering instruments. Methods Sixty volunteers, 30 males and 30 females, participated in this study. Various parameters of facial pores were assessed using the Robo Skin Analyzer®. The facial Sebum Secretion and skin elasticity were measured using the Sebumeter® and the Cutometer®, respectively. These data were compared and correlated to examine the possible relationship between facial pores and age, Sebum Secretion and skin elasticity, according to gender and the presence of acne. Results Male gender and the existence of acne were correlated with higher number of facial pores. Sebum Secretion levels showed positive correlation with facial pores. The R7 parameter of skin elasticity was negatively correlated with facial pores, suggesting increased facial pores with decreased skin elasticity. However, the age and the severity of acne did not show a definite relationship with facial pores. Conclusion Male, increased Sebum and decreased skin elasticity were mostly correlated with facial pore development. Further studies on population with various demographic profiles and more severe acne may be helpful to elucidate the potential effect of aging and acne severity on facial pores.

  • The clinical features of late onset acne compared with early onset acne in women.
    Journal of the European Academy of Dermatology and Venereology : JEADV, 2011
    Co-Authors: C. W. Choi, K.c. Park, Dh Lee, Hs Kim, Kim, Sang Woong Youn
    Abstract:

    Background  Little is known about the clinical characteristics of acne based on the age of onset. Objectives  The aim of this study was to investigate the clinical characteristics of patients according to the age of onset of acne and evaluate whether the findings were related to regional differences in the density of Propionibacterium acnes or the levels of Sebum Secretion. Methods  A total of 89 women were recruited. The acne lesions were assessed by counting the lesions using standard digital photographs. Digital fluorescent photography for the evaluation of the density of P. acnes were taken and quantitative measurements of facial Sebum Secretion were performed. Results  In women with acne, the age of onset was negatively correlated with the number of comedones and the proportion of comedones. By comparing the number of comedones and the proportion of comedones, onset of acne after 21 years of age was defined as late onset acne. In the patients with late onset acne, the number of comedones, the total number of acne lesions and the proportions of comedones were significantly less than in the patients with early onset acne. However, there were no significant differences in the fluorescence density of P. acnes or the level of Sebum Secretion between the two groups. Conclusions  The results of this study, using objective evaluation tools, suggest that late onset acne has different clinical characteristics. Other possible factors might explain the clinical differences in late onset acne.

Kyoung Chan Park - One of the best experts on this subject based on the ideXlab platform.

  • Sebum acne skin elasticity and gender difference which is the major influencing factor for facial pores
    Skin Research and Technology, 2013
    Co-Authors: Jae Woo Choi, Seock Won Youn, Kyoung Chan Park
    Abstract:

    Background Enlarged facial pores have been esthetic problems and have become a matter of cosmetic concern. Several factors are supposed to be related to the enlargement of facial pores, although scientific evaluations were not performed yet. Objective To assess the correlation between facial pores and possible relating factors such as age, gender, Sebum Secretion, skin elasticity, and the presence of acne, using objective bioengineering instruments. Methods Sixty volunteers, 30 males and 30 females, participated in this study. Various parameters of facial pores were assessed using the Robo Skin Analyzer®. The facial Sebum Secretion and skin elasticity were measured using the Sebumeter® and the Cutometer®, respectively. These data were compared and correlated to examine the possible relationship between facial pores and age, Sebum Secretion and skin elasticity, according to gender and the presence of acne. Results Male gender and the existence of acne were correlated with higher number of facial pores. Sebum Secretion levels showed positive correlation with facial pores. The R7 parameter of skin elasticity was negatively correlated with facial pores, suggesting increased facial pores with decreased skin elasticity. However, the age and the severity of acne did not show a definite relationship with facial pores. Conclusion Male, increased Sebum and decreased skin elasticity were mostly correlated with facial pore development. Further studies on population with various demographic profiles and more severe acne may be helpful to elucidate the potential effect of aging and acne severity on facial pores.

  • Sebum, acne, skin elasticity, and gender difference – which is the major influencing factor for facial pores?
    Skin research and technology : official journal of International Society for Bioengineering and the Skin (ISBS) [and] International Society for Digita, 2011
    Co-Authors: B. Y. Kim, Jae Woo Choi, Kyoung Chan Park, Sang Woong Youn
    Abstract:

    Background Enlarged facial pores have been esthetic problems and have become a matter of cosmetic concern. Several factors are supposed to be related to the enlargement of facial pores, although scientific evaluations were not performed yet. Objective To assess the correlation between facial pores and possible relating factors such as age, gender, Sebum Secretion, skin elasticity, and the presence of acne, using objective bioengineering instruments. Methods Sixty volunteers, 30 males and 30 females, participated in this study. Various parameters of facial pores were assessed using the Robo Skin Analyzer®. The facial Sebum Secretion and skin elasticity were measured using the Sebumeter® and the Cutometer®, respectively. These data were compared and correlated to examine the possible relationship between facial pores and age, Sebum Secretion and skin elasticity, according to gender and the presence of acne. Results Male gender and the existence of acne were correlated with higher number of facial pores. Sebum Secretion levels showed positive correlation with facial pores. The R7 parameter of skin elasticity was negatively correlated with facial pores, suggesting increased facial pores with decreased skin elasticity. However, the age and the severity of acne did not show a definite relationship with facial pores. Conclusion Male, increased Sebum and decreased skin elasticity were mostly correlated with facial pore development. Further studies on population with various demographic profiles and more severe acne may be helpful to elucidate the potential effect of aging and acne severity on facial pores.

  • the facial red fluorescence of ultraviolet photography is this color due to propionibacterium acnes or the unknown content of secreted Sebum
    Skin Research and Technology, 2009
    Co-Authors: Sang Woong Youn, Jun Hyung Kim, Jai Eun Lee, Sun Ok Kim, Kyoung Chan Park
    Abstract:

    Background/purpose: Red fluorescence of the face induced by ultraviolet light is thought to be due to Propionibacterium acnes. However, recently there are reports correlating this red fluorescence with the amount of facial Sebum Secretion. This study was performed to investigate the relationship between the areas of facial red fluorescence with culture results of P. acnes and the amount of Sebum Secretion. Methods: Nineteen patients with acne were included. P. acnes cultures were done on specimens obtained from areas with red fluorescence. In addition, the amount of facial Sebum Secretion and the skin surface pH (SSPH) were measured. Correlation analysis of these parameters and the culture results were performed with the image analysis data from the red fluorescence of the face. Results: P. acnes was cultured in 36.5% of cases. The correlation of the culture rate with the red fluorescence areas was not significant. After classifying the patients into high-Sebum and low-Sebum groups, there was a significant difference in the red fluorescence areas. In addition, the red fluorescence area correlated with the SSPH. Conclusions: The red fluorescence area showed a stronger correlation with Sebum Secretion than with the presence of P. acnes. This finding suggests that the red fluorescence is affected by Sebum not just P. acnes.

  • Comparison of Sebum Secretion, skin type, pH in humans with and without acne
    Archives of Dermatological Research, 2006
    Co-Authors: Sunyoung Choi, Hee-jin Byun, Rajul A. Patel, Annie H. Shinn, Kyoung Chan Park, Sang Woong Youn
    Abstract:

    Differences of skin type and pH between subjects with and without acne have not been investi- gated. In addition, the relationship between Sebum Secretion and pH in these populations has not been determined. This study assessed the differences in objective and subjective skin types between these two groups. Secondly, this study evaluated the difference in pH on five facial areas (forehead, nose, chin, right and left cheek) between the two populations. Lastly, the relationship between pH and Sebum Secretion was analyzed in each population. Sebum casual levels (CL) of the five facial areas in 36 Koreans with acne and 47 Koreans without acne were measured by using a Se- bumeter SM 815 � and subjects were classified into objective skin types by CL. Subjects reported the type of skin they believed they had, which determined the subjective skin type. The pH levels of the five facial areas were measured by the Skin-pH-Meter PH 905 � . Data was assessed with adequate statistical tests depending on data type and distribution. Among the five areas, the nose of the subjects with acne showed a significantly higher CL, compared to the subjects without acne. This difference in CL on the nose re- sulted in the difference in CL on the T-zone and mean facial Sebum excretions (MFSE). Although CL dif- fered, objective skin types did not differ between the two groups (P > 0.05), but the subjective skin types differed significantly (P = 0.001). In addition, the objective skin types were significantly different than the subjective skin types in subjects with acne (P = 0.001), whereas the two skin types did not differ in subjects without acne. Subjects with acne actually overestimated their skin types and stated their skin types were ''oilier'' than they were. In respect to pH, none of the five areas differed significantly between the two groups. Among the five sites in subjects with acne, CL showed a significant negative correlation with pH on the left (r 2 = 0.12) and right (r 2 = 0.15) cheeks, which resulted in a significant negative correlation on the U-zone (r 2 = 0.14). In contrast, in subjects without acne, there was a significant negative correlation be- tween CL and pH on the forehead (r 2 = 0.10) and chin (r 2 = 0.16), which led to a significant negative correla- tion on the T-zone (r 2 = 0.14).

  • comparison of Sebum Secretion skin type ph in humans with and without acne
    Archives of Dermatological Research, 2006
    Co-Authors: Myo Kyoung Kim, Sunyoung Choi, Hee-jin Byun, Kyoung Chan Park, Chang Hun Huh, Rajul A. Patel
    Abstract:

    Differences of skin type and pH between subjects with and without acne have not been investigated. In addition, the relationship between Sebum Secretion and pH in these populations has not been determined. This study assessed the differences in objective and subjective skin types between these two groups. Secondly, this study evaluated the difference in pH on five facial areas (forehead, nose, chin, right and left cheeks) between the two populations. Lastly, the relationship between pH and Sebum Secretion was analyzed in each population. Sebum casual levels (CL) of the five facial areas in 36 Koreans with acne and 47 Koreans without acne were measured by using a Sebumeter SM 815 and subjects were classified into objective skin types by CL. Subjects reported the type of skin they believed they had, which determined the subjective skin type. The pH levels of the five facial areas were measured by the Skin-pH-Meter PH 905. Data were assessed with adequate statistical tests depending on data type and distribution. Among the five areas, the nose of the subjects with acne showed a significantly higher CL, compared to the subjects without acne. This difference in CL on the nose resulted in the difference in CL on the T-zone and mean facial Sebum excretions (MFSE). Although CL differed, objective skin types did not differ between the two groups (P > 0.05), but the subjective skin types differed significantly (P = 0.001). In addition, the objective skin types were significantly different than the subjective skin types in subjects with acne (P = 0.001), whereas the two skin types did not differ in subjects without acne. Subjects with acne actually overestimated their skin types and stated their skin types were "oilier" than they were. In respect to pH, none of the five areas differed significantly between the two groups. Among the five sites in subjects with acne, CL showed a significant negative correlation with pH on the left (r (2 )=0.12) and right (r ( 2 )=0.15) cheeks, which resulted in a significant negative correlation on the U-zone (r ( 2 )=0.14). In contrast, in subjects without acne, there was a significant negative correlation between CL and pH on the forehead (r ( 2 )=0.10) and chin (r ( 2 )=0.16), which led to a significant negative correlation on the T-zone (r ( 2 )=0.14).

Sunyoung Choi - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of Sebum Secretion, skin type, pH in humans with and without acne
    Archives of Dermatological Research, 2006
    Co-Authors: Sunyoung Choi, Hee-jin Byun, Rajul A. Patel, Annie H. Shinn, Kyoung Chan Park, Sang Woong Youn
    Abstract:

    Differences of skin type and pH between subjects with and without acne have not been investi- gated. In addition, the relationship between Sebum Secretion and pH in these populations has not been determined. This study assessed the differences in objective and subjective skin types between these two groups. Secondly, this study evaluated the difference in pH on five facial areas (forehead, nose, chin, right and left cheek) between the two populations. Lastly, the relationship between pH and Sebum Secretion was analyzed in each population. Sebum casual levels (CL) of the five facial areas in 36 Koreans with acne and 47 Koreans without acne were measured by using a Se- bumeter SM 815 � and subjects were classified into objective skin types by CL. Subjects reported the type of skin they believed they had, which determined the subjective skin type. The pH levels of the five facial areas were measured by the Skin-pH-Meter PH 905 � . Data was assessed with adequate statistical tests depending on data type and distribution. Among the five areas, the nose of the subjects with acne showed a significantly higher CL, compared to the subjects without acne. This difference in CL on the nose re- sulted in the difference in CL on the T-zone and mean facial Sebum excretions (MFSE). Although CL dif- fered, objective skin types did not differ between the two groups (P > 0.05), but the subjective skin types differed significantly (P = 0.001). In addition, the objective skin types were significantly different than the subjective skin types in subjects with acne (P = 0.001), whereas the two skin types did not differ in subjects without acne. Subjects with acne actually overestimated their skin types and stated their skin types were ''oilier'' than they were. In respect to pH, none of the five areas differed significantly between the two groups. Among the five sites in subjects with acne, CL showed a significant negative correlation with pH on the left (r 2 = 0.12) and right (r 2 = 0.15) cheeks, which resulted in a significant negative correlation on the U-zone (r 2 = 0.14). In contrast, in subjects without acne, there was a significant negative correlation be- tween CL and pH on the forehead (r 2 = 0.10) and chin (r 2 = 0.16), which led to a significant negative correla- tion on the T-zone (r 2 = 0.14).

  • comparison of Sebum Secretion skin type ph in humans with and without acne
    Archives of Dermatological Research, 2006
    Co-Authors: Myo Kyoung Kim, Sunyoung Choi, Hee-jin Byun, Kyoung Chan Park, Chang Hun Huh, Rajul A. Patel
    Abstract:

    Differences of skin type and pH between subjects with and without acne have not been investigated. In addition, the relationship between Sebum Secretion and pH in these populations has not been determined. This study assessed the differences in objective and subjective skin types between these two groups. Secondly, this study evaluated the difference in pH on five facial areas (forehead, nose, chin, right and left cheeks) between the two populations. Lastly, the relationship between pH and Sebum Secretion was analyzed in each population. Sebum casual levels (CL) of the five facial areas in 36 Koreans with acne and 47 Koreans without acne were measured by using a Sebumeter SM 815 and subjects were classified into objective skin types by CL. Subjects reported the type of skin they believed they had, which determined the subjective skin type. The pH levels of the five facial areas were measured by the Skin-pH-Meter PH 905. Data were assessed with adequate statistical tests depending on data type and distribution. Among the five areas, the nose of the subjects with acne showed a significantly higher CL, compared to the subjects without acne. This difference in CL on the nose resulted in the difference in CL on the T-zone and mean facial Sebum excretions (MFSE). Although CL differed, objective skin types did not differ between the two groups (P > 0.05), but the subjective skin types differed significantly (P = 0.001). In addition, the objective skin types were significantly different than the subjective skin types in subjects with acne (P = 0.001), whereas the two skin types did not differ in subjects without acne. Subjects with acne actually overestimated their skin types and stated their skin types were "oilier" than they were. In respect to pH, none of the five areas differed significantly between the two groups. Among the five sites in subjects with acne, CL showed a significant negative correlation with pH on the left (r (2 )=0.12) and right (r ( 2 )=0.15) cheeks, which resulted in a significant negative correlation on the U-zone (r ( 2 )=0.14). In contrast, in subjects without acne, there was a significant negative correlation between CL and pH on the forehead (r ( 2 )=0.10) and chin (r ( 2 )=0.16), which led to a significant negative correlation on the T-zone (r ( 2 )=0.14).

  • regional and seasonal variations in facial Sebum Secretions a proposal for the definition of combination skin type
    Skin Research and Technology, 2005
    Co-Authors: Jungim Na, Sunyoung Choi, Sang Woong Youn, Kyoung Chan Park
    Abstract:

    Background/aims: Facial Sebum Secretions are known to change under various circumstances. Facial skin types have been categorized as oily, normal, dry, and combination types. However, these have been evaluated subjectively by individuals to date, and no objective accepted standard measurement method exists. The combination skin type is most common, but its definition is vaguer than the definitions of the other skin types. Methods: We measured facial Sebum Secretions with Sebumeter s . Sebum Secretions were measured at five sites of the face seasonally for a year, in the same volunteers. Using the data obtained we developed a set of rules to define the combination skin type. Results: Regional differences in Sebum Secretion were confirmed. Sebum Secretions on forehead, nose, and chin were higher than on both cheeks. Summer was found to be the highest Sebum-secreting season, and seasonal variations were found in the T- and U-zones. A mismatch of skin type in the T- and U-zones in more than two seasons appears to be close to subjective ratings of what is described as the ‘combination’ skin type. Conclusion: We showed that the face shows definitive regional and seasonal variations in Sebum Secretion. To define the combination skin type, seasonal variations in Sebum Secretion should be considered in addition to regional variations.

  • Comparative Study of Effects by Glycolic Acid Peeling and Jessner's Solution Peeling on Facial Sebum Secretion in Patients with Facial Acne
    Journal of Clinical Dermatology, 2004
    Co-Authors: Seung-ho Lee, Sunyoung Choi, Kyoung Chan Park, Chang Hun Huh, Sang Woong Youn
    Abstract:

    Background: Glycolic acid and Jessner's solution have been popular agents for superficial chemical peeling to treat facial acne. Increased Sebum Secretion is one of the major etiological factors of acne. There has been no report to compare effects on Sebum Secretion in patients with facial acne between glycolic acid peeling and Jessner's solution peeling. Objective: We compared the effects on Sebum Secretion in patients with facial acne after glycolic acid peeling or Jessner's solution peeling. Methods: Twenty patients with facial acne vulgaris were studied. Eight patients were treated with 30% glycolic acid peeling and twelve patients with Jessner's solution peeling. Before and 2 weeks after the treatment, the Sebum levels of forehead, nose, center of chin and both cheeks were measured by using Sebumeter. Results: The Sebum levels were not significantly changed after 30% glycolic acid peeling. After Jessner's solution peeling, the total average, and average of T-zone of Sebum levels, were reduced significantly (p

Rajul A. Patel - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of Sebum Secretion, skin type, pH in humans with and without acne
    Archives of Dermatological Research, 2006
    Co-Authors: Sunyoung Choi, Hee-jin Byun, Rajul A. Patel, Annie H. Shinn, Kyoung Chan Park, Sang Woong Youn
    Abstract:

    Differences of skin type and pH between subjects with and without acne have not been investi- gated. In addition, the relationship between Sebum Secretion and pH in these populations has not been determined. This study assessed the differences in objective and subjective skin types between these two groups. Secondly, this study evaluated the difference in pH on five facial areas (forehead, nose, chin, right and left cheek) between the two populations. Lastly, the relationship between pH and Sebum Secretion was analyzed in each population. Sebum casual levels (CL) of the five facial areas in 36 Koreans with acne and 47 Koreans without acne were measured by using a Se- bumeter SM 815 � and subjects were classified into objective skin types by CL. Subjects reported the type of skin they believed they had, which determined the subjective skin type. The pH levels of the five facial areas were measured by the Skin-pH-Meter PH 905 � . Data was assessed with adequate statistical tests depending on data type and distribution. Among the five areas, the nose of the subjects with acne showed a significantly higher CL, compared to the subjects without acne. This difference in CL on the nose re- sulted in the difference in CL on the T-zone and mean facial Sebum excretions (MFSE). Although CL dif- fered, objective skin types did not differ between the two groups (P > 0.05), but the subjective skin types differed significantly (P = 0.001). In addition, the objective skin types were significantly different than the subjective skin types in subjects with acne (P = 0.001), whereas the two skin types did not differ in subjects without acne. Subjects with acne actually overestimated their skin types and stated their skin types were ''oilier'' than they were. In respect to pH, none of the five areas differed significantly between the two groups. Among the five sites in subjects with acne, CL showed a significant negative correlation with pH on the left (r 2 = 0.12) and right (r 2 = 0.15) cheeks, which resulted in a significant negative correlation on the U-zone (r 2 = 0.14). In contrast, in subjects without acne, there was a significant negative correlation be- tween CL and pH on the forehead (r 2 = 0.10) and chin (r 2 = 0.16), which led to a significant negative correla- tion on the T-zone (r 2 = 0.14).

  • comparison of Sebum Secretion skin type ph in humans with and without acne
    Archives of Dermatological Research, 2006
    Co-Authors: Myo Kyoung Kim, Sunyoung Choi, Hee-jin Byun, Kyoung Chan Park, Chang Hun Huh, Rajul A. Patel
    Abstract:

    Differences of skin type and pH between subjects with and without acne have not been investigated. In addition, the relationship between Sebum Secretion and pH in these populations has not been determined. This study assessed the differences in objective and subjective skin types between these two groups. Secondly, this study evaluated the difference in pH on five facial areas (forehead, nose, chin, right and left cheeks) between the two populations. Lastly, the relationship between pH and Sebum Secretion was analyzed in each population. Sebum casual levels (CL) of the five facial areas in 36 Koreans with acne and 47 Koreans without acne were measured by using a Sebumeter SM 815 and subjects were classified into objective skin types by CL. Subjects reported the type of skin they believed they had, which determined the subjective skin type. The pH levels of the five facial areas were measured by the Skin-pH-Meter PH 905. Data were assessed with adequate statistical tests depending on data type and distribution. Among the five areas, the nose of the subjects with acne showed a significantly higher CL, compared to the subjects without acne. This difference in CL on the nose resulted in the difference in CL on the T-zone and mean facial Sebum excretions (MFSE). Although CL differed, objective skin types did not differ between the two groups (P > 0.05), but the subjective skin types differed significantly (P = 0.001). In addition, the objective skin types were significantly different than the subjective skin types in subjects with acne (P = 0.001), whereas the two skin types did not differ in subjects without acne. Subjects with acne actually overestimated their skin types and stated their skin types were "oilier" than they were. In respect to pH, none of the five areas differed significantly between the two groups. Among the five sites in subjects with acne, CL showed a significant negative correlation with pH on the left (r (2 )=0.12) and right (r ( 2 )=0.15) cheeks, which resulted in a significant negative correlation on the U-zone (r ( 2 )=0.14). In contrast, in subjects without acne, there was a significant negative correlation between CL and pH on the forehead (r ( 2 )=0.10) and chin (r ( 2 )=0.16), which led to a significant negative correlation on the T-zone (r ( 2 )=0.14).

Hee-jin Byun - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of Sebum Secretion, skin type, pH in humans with and without acne
    Archives of Dermatological Research, 2006
    Co-Authors: Sunyoung Choi, Hee-jin Byun, Rajul A. Patel, Annie H. Shinn, Kyoung Chan Park, Sang Woong Youn
    Abstract:

    Differences of skin type and pH between subjects with and without acne have not been investi- gated. In addition, the relationship between Sebum Secretion and pH in these populations has not been determined. This study assessed the differences in objective and subjective skin types between these two groups. Secondly, this study evaluated the difference in pH on five facial areas (forehead, nose, chin, right and left cheek) between the two populations. Lastly, the relationship between pH and Sebum Secretion was analyzed in each population. Sebum casual levels (CL) of the five facial areas in 36 Koreans with acne and 47 Koreans without acne were measured by using a Se- bumeter SM 815 � and subjects were classified into objective skin types by CL. Subjects reported the type of skin they believed they had, which determined the subjective skin type. The pH levels of the five facial areas were measured by the Skin-pH-Meter PH 905 � . Data was assessed with adequate statistical tests depending on data type and distribution. Among the five areas, the nose of the subjects with acne showed a significantly higher CL, compared to the subjects without acne. This difference in CL on the nose re- sulted in the difference in CL on the T-zone and mean facial Sebum excretions (MFSE). Although CL dif- fered, objective skin types did not differ between the two groups (P > 0.05), but the subjective skin types differed significantly (P = 0.001). In addition, the objective skin types were significantly different than the subjective skin types in subjects with acne (P = 0.001), whereas the two skin types did not differ in subjects without acne. Subjects with acne actually overestimated their skin types and stated their skin types were ''oilier'' than they were. In respect to pH, none of the five areas differed significantly between the two groups. Among the five sites in subjects with acne, CL showed a significant negative correlation with pH on the left (r 2 = 0.12) and right (r 2 = 0.15) cheeks, which resulted in a significant negative correlation on the U-zone (r 2 = 0.14). In contrast, in subjects without acne, there was a significant negative correlation be- tween CL and pH on the forehead (r 2 = 0.10) and chin (r 2 = 0.16), which led to a significant negative correla- tion on the T-zone (r 2 = 0.14).

  • comparison of Sebum Secretion skin type ph in humans with and without acne
    Archives of Dermatological Research, 2006
    Co-Authors: Myo Kyoung Kim, Sunyoung Choi, Hee-jin Byun, Kyoung Chan Park, Chang Hun Huh, Rajul A. Patel
    Abstract:

    Differences of skin type and pH between subjects with and without acne have not been investigated. In addition, the relationship between Sebum Secretion and pH in these populations has not been determined. This study assessed the differences in objective and subjective skin types between these two groups. Secondly, this study evaluated the difference in pH on five facial areas (forehead, nose, chin, right and left cheeks) between the two populations. Lastly, the relationship between pH and Sebum Secretion was analyzed in each population. Sebum casual levels (CL) of the five facial areas in 36 Koreans with acne and 47 Koreans without acne were measured by using a Sebumeter SM 815 and subjects were classified into objective skin types by CL. Subjects reported the type of skin they believed they had, which determined the subjective skin type. The pH levels of the five facial areas were measured by the Skin-pH-Meter PH 905. Data were assessed with adequate statistical tests depending on data type and distribution. Among the five areas, the nose of the subjects with acne showed a significantly higher CL, compared to the subjects without acne. This difference in CL on the nose resulted in the difference in CL on the T-zone and mean facial Sebum excretions (MFSE). Although CL differed, objective skin types did not differ between the two groups (P > 0.05), but the subjective skin types differed significantly (P = 0.001). In addition, the objective skin types were significantly different than the subjective skin types in subjects with acne (P = 0.001), whereas the two skin types did not differ in subjects without acne. Subjects with acne actually overestimated their skin types and stated their skin types were "oilier" than they were. In respect to pH, none of the five areas differed significantly between the two groups. Among the five sites in subjects with acne, CL showed a significant negative correlation with pH on the left (r (2 )=0.12) and right (r ( 2 )=0.15) cheeks, which resulted in a significant negative correlation on the U-zone (r ( 2 )=0.14). In contrast, in subjects without acne, there was a significant negative correlation between CL and pH on the forehead (r ( 2 )=0.10) and chin (r ( 2 )=0.16), which led to a significant negative correlation on the T-zone (r ( 2 )=0.14).