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Publication Maxillary Molar Distalization with Clear Aligner Therapy and Infrazygomatic Temporary Anchorage Devices System(2025) Christie Shen; Li, Chenshuang; Chung, Chun-HsiChapter 1: Molar Distalization by Clear Aligners with Sequential Distalization Protocol Introduction: With the popularity of clear aligners, the sequential distalization protocol has been more commonly used for molar distalization. However, the amount of molar distalization that can be achieved, as well as the accompanying side effects on the sagittal dimension, are unclear. Methods: Registered with PROSPERO (CRD42023447211), relevant original studies were screened from seven databases (MEDLINE [PubMed], EBSCOhost, Web of Science, Elsevier [SCOPUS], Cochrane, LILACS [Latin American and Caribbean Health Sciences Literature], and Google Scholar) supplemented by a manual search of the references of the full-reading manuscripts by two investigators independently. A risk of bias assessment was conducted, relevant data were extracted, and meta-analysis was performed using RStudio. Results: After the screening, 13 articles (11 involving maxillary distalization, two involving mandibular distalization) met the inclusion criteria. All studies had a high or medium risk of bias. The meta-analysis revealed that the maxillary first molar (U6) mesiobuccal cusp was distalized 2.07 mm [1.38 mm, 2.77 mm] based on the post-distalization dental model superimposition, and the U6 crown was distalized 2.00 mm [0.77 mm, 3.24 mm] based on the post-treatment lateral cephalometric evaluation. However, the U6 mesiobuccal root showed less distalization of 1.13 mm [−1.34 mm, 3.60 mm], indicating crown distal tipping, which was validated by meta-analysis (U6-PP angle: 2.19° [1.06°, 3.33°]). In addition, intra-arch anchorage loss was observed at the post-distalization time point (U1 protrusion: 0.39 mm [0.27 mm, 0.51 mm]), which was corrected at the post-treatment time point (incisal edge-PTV distance: −1.50 mm [−2.61 mm, −0.39 mm]). Conclusion: About 2 mm maxillary molar distalization can be achieved with the sequential distalization protocol, accompanied by slight molar crown distal tipping. Additional studies on this topic are needed due to the high risk of bias in currently available studies. Chapter 2: Vertical Control in Molar Distalization by Clear Aligners Background: Molar distalization is used to correct molar relationships or to create space for mild anterior crowding. However, whether clear aligners can provide proper vertical control with the sequential distalization strategy has been highly debated. Thus, the current study aimed to systematically review the amount of dentoskeletal changes in the vertical dimension that results from sequential molar distalization in clear aligner therapy without temporary anchorage devices (TADs). Methods: Registered with PROSPERO (CRD42023447211), relevant original studies were screened from seven databases and supplemented by a manual search by two investigators independently. Articles were screened against inclusion and exclusion criteria, and a risk of bias assessment was conducted for each included article. Relevant data were extracted from the included articles and meta-analysis was performed using RStudio. Results: Eleven articles (nine for maxillary distalization and two for mandibular distalization) were selected for the final review. All studies have a high or medium risk of bias. For maxillary molar distalization, the meta-analysis revealed 0.26 mm [0.23 mm, 0.29 mm] of maxillary first molar intrusion based on post-distalization dental model analysis, as well as 0.50 mm [−0.78 mm, 1.78 mm] of maxillary first molar intrusion and 0.60 mm [−0.42 mm, 1.62 mm] of maxillary second molar intrusion based on post-treatment lateral cephalometric analysis. Skeletally, there was a −0.33° [−0.67°, 0.02°] change in the SN-GoGn angle, −0.23° [−0.30°, 0.75°] change in the SN-MP angle, and 0.09° [−0.83°, 1.01°] change in the PP-GoGn angle based on post-treatment lateral cephalometric analysis. There was insufficient data for meta-analysis for mandibular molar distalization. Conclusions: No significant changes in vertical dimension were observed, both dentally and skeletally, after maxillary molar distalization with a sequential distalization strategy. However, further studies on this topic are needed due to the high risk of bias in the currently available studies. Chapter 3: Maxillary Molar Distalization with Clear Aligner Therapy and Infrazygomatic Temporary Anchorage Devices System Introduction: Based on systematic reviews and meta- analyses, approximately 2 mm of maxillary molar distalization can be achieved with sequential molar distalization with clear aligner therapy (CAT) without skeletal anchorage. Distalization is accompanied by significant distal crown tipping and insignificant changes in the vertical dimension. Thus, combining CAT with temporary anchorage devices (TADs) has been proposed, but a detailed evaluation is lacking. Methods: This retrospective study evaluated pre-treatment (T1) and post-anterior retraction (T2) cone beam computed tomography (CBCT) images and digital models of adult patients treated with CAT + infrazygomatic TADs with at least 1 mm of programed maxillary first molar distalization. Achieved tooth movement shown on the CBCT and intraoral scan was compared to prescribed ClinCheck tooth movement. Results: The present study included 38 sides from 21 patients (17 females, 4 males; 28.71±4.16 years old at T1). At the crown level, about 1 mm of molar distalization was achieved (first molar (U6): 1.05 mm [-0.8, 3.6] based on digital models, 0.80 mm [-1.1, 3.4] based on CBCTs; second molar (U7): 0.95 mm [-1.8, 4.4] based on digital models, 1.25 mm [-1.9, 3.7] based on CBCTs), which is significantly lower than the prescribed ClinCheck movement (U6: 3.05 mm [1.0, 5.6]; U7: 3.05 mm [0.9, 6.1]). We observed limited crown distal tipping and mesial-out rotation but significant buccal expansion and intrusion of the maxillary molars. In addition, a negative correlation was detected between the amount of prescribed molar distal movement and the distalization efficacy. Measurements based on the CBCT and digital models were comparable for maxillary molar, rotation and tipping, as well as maxillary central incisor retraction and buccal crown torque. However, CBCT and digital model measurements showed discrepancies in vertical measurements. Conclusion: The CAT+TADs system did not significantly improve the efficacy of maxillary molar distalization when compared to existing clear aligner studies but provided more bodily movement and intrusion of the molars. As all patients in this study were treated with TADs, further studies with comparative designs are needed to isolate and evaluate the contribution of TADs to molar distalization.Publication A RETROSPECTIVE COMPARARISON OF TWO SURGICAL APPROACHES USED TO TREAT ALTERED PASSIVE ERUPTION(2025-05-19) Meshari Ben Hassan; Jonathan Korostoff; Howard Fraiman; Harold Baumgarten; Tun-Jan Wang; Korostoff, JonathanBackground: Altered passive eruption (APE) is a clinical condition characterized by insufficient apical migration of the gingival margin, resulting in a gummy smile and short clinical crowns without pathological findings. The condition can be treated using various surgical approaches, including gingivectomy, apically repositioned flap, osseous recontouring, or a combination of these. The surgical procedure of choice depends on the APE type and subtype, as described by Coslet et al. The aim of this study was to compare two commonly used esthetic crown lengthening techniques—non-staged (submarginal incision) and staged (flap reposition)—in patients with APE, focusing on long-term gingival margin stability. Materials and Methods: A retrospective data review was conducted on six APE patients, divided into two groups: submarginal incisions (non-staged) and flap reposition (staged), with three patients in each group. Preoperative assessments included cone beam computed tomography (CBCT), intra-oral scanning, and photographs. A mock-up procedure was performed using CBCT and intra-oral scans to simulate the expected outcome. After surgery, intra-oral scans were taken at 3 and 6 months, and gingival margin positions were compared with baseline measurements. Descriptive statistics, t-tests, and Wilcoxon signed-rank tests were used for statistical analysis. Results: Analysis of the data showed that both techniques demonstrated similar gingival margin stability at the 6-month follow-up. However, the flap reposition technique exhibited more significant changes in gingival margin position during the first 3 months and required fewer corrective procedures, alongside a wider band of keratinized tissue relative to the one-stage approach. These findings were statistically significant at the 3-month follow-up, but no significant difference was found at the 6-month mark. Conclusions: Advanced imaging, such as CBCT, played a critical role in pre-surgical planning, particularly in identifying the cementoenamel junction (CEJ) and guiding the surgical approach. Both techniques are viable for esthetic crown lengthening in APE patients, but the flap reposition approach may offer better gingival stability and fewer post-operative complications. Further studies with larger sample sizes and long-term follow-ups are necessary to confirm these findings and refine clinical decision-making for APE management.Publication A RETROSPECTIVE COMPARARISON OF TWO SURGICAL APPROACHES USED TO TREAT ALTERED PASSIVE ERUPTION(2025-05-19) Meshari Ben Hassan; Jonathan Korostoff; Howard Fraiman; Harold Baumgarten; Tun-Jan Wang; Korostoff, JonathanBackground: Altered passive eruption (APE) is a clinical condition characterized by insufficient apical migration of the gingival margin, resulting in a gummy smile and short clinical crowns without pathological findings. The condition can be treated using various surgical approaches, including gingivectomy, apically repositioned flap, osseous recontouring, or a combination of these. The surgical procedure of choice depends on the APE type and subtype, as described by Coslet et al. The aim of this study was to compare two commonly used esthetic crown lengthening techniques—non-staged (submarginal incision) and staged (flap reposition)—in patients with APE, focusing on long-term gingival margin stability. Materials and Methods: A retrospective data review was conducted on six APE patients, divided into two groups: submarginal incisions (non-staged) and flap reposition (staged), with three patients in each group. Preoperative assessments included cone beam computed tomography (CBCT), intra-oral scanning, and photographs. A mock-up procedure was performed using CBCT and intra-oral scans to simulate the expected outcome. After surgery, intra-oral scans were taken at 3 and 6 months, and gingival margin positions were compared with baseline measurements. Descriptive statistics, t-tests, and Wilcoxon signed-rank tests were used for statistical analysis. Results: Analysis of the data showed that both techniques demonstrated similar gingival margin stability at the 6-month follow-up. However, the flap reposition technique exhibited more significant changes in gingival margin position during the first 3 months and required fewer corrective procedures, alongside a wider band of keratinized tissue relative to the one-stage approach. These findings were statistically significant at the 3-month follow-up, but no significant difference was found at the 6-month mark. Conclusions: Advanced imaging, such as CBCT, played a critical role in pre-surgical planning, particularly in identifying the cementoenamel junction (CEJ) and guiding the surgical approach. Both techniques are viable for esthetic crown lengthening in APE patients, but the flap reposition approach may offer better gingival stability and fewer post-operative complications. Further studies with larger sample sizes and long-term follow-ups are necessary to confirm these findings and refine clinical decision-making for APE management.Publication Recent Residence in Controlled Living Environments and HIV Sexual Risk Behaviors Among Women on Probation and Parole(2025) Graham, Fritz; Engstrom, MalittaStudy Purpose In the United States, approximately one million women are on probation and/or parole. A majority of women on probation and/or parole have recently resided in a controlled living environment (CLE), and a disproportionate number of women on probation and parole are living with HIV. Prior research has examined associations between recent residence in CLEs, substance use, and histories of victimization among women; however, residing in a controlled living environment and associations with HIV sexual risk behaviors have received limited attention. This study used Nyamathi’s (1989) Comprehensive Health Seeking and Coping Paradigm (CHSCP) as a guiding framework to examine associations between recent residence in a controlled living environment and HIV sexual risk behaviors among women on probation and parole. Methods This study involved secondary analysis of baseline data gathered through the NIDA-funded Women’s Health Research Study, which was conducted in an urban county in Kentucky. Study participants were recruited through flyers posted in probation offices, referrals from probation and parole officers, direct recruitment by interviewers and by mail, and local media announcements. Interviews were conducted by trained interviewers and relied on audio computer-assisted interviewing (ACASI) technology. A total of 406 women on probation or parole with histories of lifetime victimization participated in baseline interviews, which included attention to sociodemographic information, HIV risk behaviors, criminal legal system involvement, housing, mental health, victimization, substance use, social support, and other domains. STATA 17 was used to conduct all data analyses, including multiple imputation of missing data, descriptive analyses, and logistic regression analyses. Results The mean age of participants was 37.20 years old (SE=0.51). Most of the participants identified as Black/African American (42%) or White (51%). Approximately 49% of the participants recently resided in a CLE, and approximately 5% of the participants were living with HIV. Bivariate and multivariable regression analyses found no statistically significant associations between recent residence in a CLE and engagement in HIV sexual risk behaviors. However, housing instability, intimate partner violence (IPV), and marital status were associated with increased HIV sexual risk behaviors. Age, occupation, and social support were associated with decreased HIV sexual risk behaviors. When the CLE definition was expanded to include halfway house residence, there was an association with increased HIV sexual risk behavior. Implications This study found that recent residence in a CLE is not associated with increased HIV sexual risk behaviors. Additional research in this area may further explore different types of controlled living environments, including halfway houses, to understand their potential associations with HIV sexual risk behaviors, as well as to explore residents’ perspectives on and experiences with their housing and HIV risks. The findings align with prior research regarding the importance of addressing housing instability, IPV, and social support in HIV risk reduction interventions among this population of women. The study also reflects the value of Nyamathi’s CHSCP as a useful framework for conceptualizing complex phenomena associated with health experiences and identifying targets of intervention to improve health outcomes among vulnerable populations.Publication PRECEPTORS, PERFORMANCE, AND PRINT: VĒḶĀḶAR ECONOMIES OF CULTURAL PRODUCTION IN MODERN SOUTH INDIA(2025) Vijayakumar, Praveen; Soneji, DaveshThis dissertation work focuses on the cultural work of the ubiquitous and highly heterogeneous dominant caste group known as vēḷāḷars (“cultivators”) in modern Tamil south India. Many vēḷāḷar subcastes are known for their relatively high ritual status, caste-endogamous marriage practices, ownership and management of agrarian land, and often, their political visibility. Significantly, for this project, vēḷāḷars also represent a group whose agrarian pasts are supplemented by their pre-eminence in the fields of literary and musical production across the Tamil-speaking world. In this dissertation I demonstrate how vēḷāḷars emerged as cultural stewards within the political matrix of colonial power through their participation in literary and musical patronage, print culture, as well as their deep involvement in the shaping of modern Tamil Śaiva religion and Dravidianist politics. My project thus seeks to reposition vēḷāḷar participation at the center of Tamil cultural production from the nineteenth to the twentieth centuries. It does so by thinking critically about the deployment of caste-based power by vēḷāḷars in the fields of musical production as well as patronage, the mediating role played by vēḷāḷar- dominated religious institutions, and the place of vēḷāḷar philanthropists and intellectuals in the cultural life of modern South India. By mobilizing extant caste-based power centered in Śaiva monasteries such those at Dharmapuram and Thiruvavaduthurai, founded by vēḷāḷar preceptors of the Śaiva Siddhānta lineage in the sixteenth century, and by publishing caste purāṇas or “mytho-genealogies” that imagined them as stewards of Tamil Śaivism and Tamil society-at- large, vēḷāḷars are also among the first authors and ideologues to forge and disseminate discourses on Dravidianism in the Tamil language in the twentieth century. Although the main focus of this project is the dominant vēḷāḷar caste community, a parallel discussion that takes place throughout the dissertation is that of service caste communities who traditionally were considered subordinate to the vēḷāḷars. Service caste communities (including hereditary musicians, dancers, and others) scramble to confirm their affiliation with vēḷāḷars and even claim vēḷāḷar-hood for themselves in the early twentieth century, and this is a stark example of vēḷāḷar power in this period. These modes of identification and the idea of “aspirational vēḷāḷar-hood” are clearly visible in the successful religious careers of two modern figures who are central to this project: Kirupāṉanta Vāriyār (1906-1993) and Cāyimātā Civa Piruntā Tevī (1927-1998). In re-centering the vēḷāḷar in the cultural history of Tamil Nadu, this dissertation provides a tangible example of how caste elites deploy culture in projects of identity-making and social ascendancy in modern India.