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Publication Evaluation of Peri-implant Health Status(2024) Kashiwagi, Kosuke; Fiorellini, JosephObjective The aim of this study was to document cofactors associated with peri-implant disease progression. Material and methods The clinical charts and radiographs of patients who received dental implant at University of Pennsylvania or outside office were reviewed for maximum 13 years. Cofactors were divided two categories in this study. Patient related factors included age, active periodontitis patient, keratinized tissue around implant, smoking, diabetes, and more than 3 co morbidities. Implant related factors included diameter, length, one or two stage surgery, screw or cement retained restoration, and restoration types. Results This study involved 1004 implants from 308 patients (mean age 76.6 ± 10.9 years). Implant survival rate was 94.2%, with 5.8% failures. At the patient level, 87.7% had surviving implants, and 12.3% had at least one failure. Active periodontitis, smoking, and having more than three comorbidities were associated with peri-implant disease. Conclusion From this retrospective study, active periodontitis patient, smoking, and more than three co morbidities might cofactors associated with peri-implant disease progression.Publication ALTERNATIVE METHODS TO SYNTHETIC-BASED DYEING ON COTTON: A COMPARATIVE SUSTAINABILITY ANALYSIS(2024) Rajesh, Anindita; Hagan, JamesThe fashion industry is currently one of the largest consumers and polluters of water. The most commonly used method of textile dyeing, using synthetic dyes, is extremely water- intensive, and the chemicals used in the production and application of these dyes leach into freshwater sources, posing a threat to both public and environmental health. This research aims to assess and compare two alternative dyeing techniques – plant-based and microbial dyes – by examining their color intensity and their impact on water consumption, waste and the environment. Each method was tested on both non-mordanted and mordanted cotton strips over periods of 24 hours and 72 hours. Photographs were taken of each cotton sample following each dyeing process, and the water remaining after the dye creation and application process was measured. It was found that microbial dyes, extracted from Serratia marcescens cultures, had stronger colorfastness than the plant-dyes obtained from onion peels, beet scraps, and avocado pits. The microbial dye yielded a bright pink color, that did not fade after sterilization, sunlight exposure, and washing, while the plant-based dye yielded a yellow-brown color that exhibited some fading. There was no difference seen between the mordanted and non-mordanted fabrics, so it is therefore recommended that a mordant not be used, to further reduce water and chemical usage within the dyeing process. While plant-based dyes are currently used by several fashion brands, microbial dyes have not been produced on a large scale. With sufficient upfront monetary investments and dedication towards research, companies with varying degrees of sustainability commitments can adopt the use of microbial dyes, using much of the same machinery and techniques currently employed in dyeing facilities. As clothing manufacturers begin to face increasing pressure to evaluate and improve sustainability throughout their supply chain, introducing microbial dyes can help reduce and eventually eliminate the need for synthetic dyes, allowing for a large reduction in a company’s water-consumption and overall environmental footprint. Making this switch will therefore allow for improved water quality and availability for communities surrounding clothing manufacturers.Publication THE HARD AND SOFT TISSUE DIMENSIONAL CHANGES FOLLOWING EXTRACTION AND RIDGE PRESERVATION WITH DIFFERENT MEMBRANES – A PILOT STUDY(2024) AlAsaad, Noor; Chang, YuChengIntroduction: Following tooth extraction, bone resorption can be expected, especially on the buccal wall. An alveolar ridge preservation procedure (ARP) is commonly performed to maintain appropriate ridge volume for future implant placement. Various materials and methods can be utilized during ARP, however, there is no consensus on the membrane selection when the intact buccal plate is present after tooth extraction. The objective of this study is to investigate the dimension changes of the hard and soft tissue followed by alveolar ridge preservation with different membranes used.Materials and Methods: This prospective randomized clinical trial aims to enroll 50 subjects divided into 5 groups of 10. Each group underwent RP with mixing allograft and xenograft(1:1 ratio) and received 1 of 5 membranes: absorbable collagen dressing (ACD), non-resorbable d-polytetrafluoroethylene (d-PTFE), cross-linked collagen membrane (CLCM), non-crosslinked ECM membrane (N-CLCM), or dehydrated human de-epithelialized amnion-chorion membrane (DHDA-C). An intraoral scan was obtained before the extraction. Immediately following the extraction, a Cone Beam CT was taken to evaluate the extraction socket (Initial-CT). 4 months after ARP, a second CBCT(Post-CT) and an intraoral scan were obtained. Measurements were performed using implant planning software. Intraoral scan files were superimposed on Initial and Post-CT. A region of interest (ROI) guide was utilized to provide an accurate slice for measurement and a horizontal reference line at 1 mm interval from the bone crest. Following the ROI guide, horizontal measurements were taken at 0-9 mm level for hard tissue and 0-3 mm level for soft tissue. Results: A total of 35 patients were enrolled in the randomized clinical trial when the report was written. After removing insufficient data, only 29 patients’ data were included in bone measurement and 21 for soft tissue measurements. ANOVA test was used for analyzing the results. The results showed no statistically significant differences in dimensional changes in hard tissue (p=0.3) and soft tissue volume (p=0.7) among different kinds of membranes used in the intact defects. Conclusion: There were no significant differences in the dimensional changes of hard and soft tissue between the membrane groups, suggesting that the membranes are equally effective in intact sockets. The rationale of the material selection is mostly a clinician’s choice. A larger sample size is needed to confirm these findings.Publication THE EFFECT OF ANTIRETROVIRAL THERAPY ON THE INTEGRATED STRESS RESPONSE IN THE CENTRAL NERVOUS SYSTEM: IN VIVO ASSESSMENT IN SIV-INFECTED RHESUS MACAQUES(2024) Razan Rashad AbedAlthaqafi; Jordan-Sciutto, Kelly; Akay-Espinoza, CaglaDespite the benefits of antiretroviral therapy (ART), a large percentage of people with HIV (PWH) still suffer from some form of neurocognitive impairment. Studies have shown that high degree of oxidative stress and inflammation remain present in the central nervous system of PWH, which can activate the integrated stress response (ISR) pathway. We previously showed that the levels of several markers for ISR activation, such as phosphorylated eukaryotic initiation factor 2α (P-eIF2α), were elevated in neurons and astrocytes in the cortex in autopsy brain tissue of PWH. Phosphorylation of eIF2α is mediated by four kinases, which will result in ISR activation, as reported in several neurodegenerative disorders. In general, ISR is an adaptive pathway; however, chronic ISR activation may contribute to neuronal damage and neurocognitive impairment in PWH. Recently, several studies have reported that certain ART drugs contribute to the persistence of HIV-associated neurocognitive disorders and can induce the ISR. The aim of the present study was to assess ISR activation in neurons, astrocytes, and oligodendrocytes in brain tissue samples of SIV-infected rhesus macaques in a lentiviral model of HIV infection. Methods We examined necropsy brain tissue specimens of 11 rhesus macaques, including SIV-infected/ART-untreated macaques (n = 3), SIV-infected/ART-treated macaques (n = 4), and uninfected/untreated (n = 4) macaques, with the aim to determine if ART aggravated ISR activation in the CNS. Formalin-fixed/paraffin-embedded sections of cortical tissue were immunofluorescently stained using an antibody to p-eIF2α to assess ISR activation and antibodies against MAP2, GFAP, and ASPA to label neurons, astrocytes, and oligodendrocytes, respectively. Results By semiquantitative analysis of images of the stained specimens we found that p-eIF2α levels in neurons was significantly higher in the SIV-infected/ART-treated group than in the SIV-infected/ART-untreated group. However, we did not observe differences in p-eIF2α levels in astrocytes the gray matter and oligodendrocytes in the white matter among the three groups. Conclusion In our study, we observed a significant increase in ISR activation in neurons in the gray matter of the SIV-infected/ART-treated rhesus macaques compared to the SIV-infected/ART-untreated rhesus macaques, which we did not observe in astrocytes and oligodendrocytes.Publication CBCT ANALYSIS OF MAXILLARY AND MANDIBULAR BUCCAL BONE THICKNESS AND HIEGHT AFTER CONVENTIANAL ORTHODONTIC TREATMENT RESULTING IN AN ALTERED ARCH FORM: A RETROSPECTIVE STUDY.(2024) Hobani, Nour; Boucher, NormandINTRODUCTION: Arch development is a common occurrence in orthodontic treatment to expand dimensions of the dental arch form to accommodate proper alignment of teeth. Less attention has been spent in the literature on the changes within the posterior region and the limitation of movement that exists in this area. The purpose of this study was to assess the consequence of using preformed arch wires for posterior arch development has on the surrounding periodontium during routine orthodontic treatment. MATERIAL AND METHODS: A retrospective CBCT study of 49 adult patients orthodontically treated with fixed appliances resulting in a change of arch. The measurements of interest were made on each CBCT scan at pretreatment (T1) and post treatment (T2) for the maxillary and mandibular first premolars (U/L4), second premolars (U/L5), and mesiobuccal (U/LM6) and (U/LD6) distobuccal roots of first molars. The parameters were: (1) alveolar bone height (ABH), (2) alveolar bone thickness (ABT), (3) transverse width Palatal-Palatal (P-P) cusps, (4) root inclination, and (5) the presence and/or absence of dehiscences/fenestrations. RESULTS: The percentage of fenestrations and dehiscences in the maxilla at T1 was 50.8% and it increased by 11.3% at T2, while in the mandible at T1 it was 66.6% and it increased by 10.3% at T2. The transverse width change was significant post-treatment. Post-nonextraction orthodontic treatment where posterior dental arch forms were expanded, there is a higher tendency to: (1) increase ABH (bone loss), (2) thinning of ABT and (3) expansion was mostly achieved by tipping rather than bodily movement. CONCLUSIONS: The results indicate that the routine practice of orthodontic arch development results in significant alterations in the dimensions of the alveolar bone. On average, all posterior teeth experienced bone loss in both the vertical and horizontal dimensions following orthodontic treatment. It is therefore strongly recommended that prior to initiating treatment of adult patients requiring uprighting posterior teeth and/or dental expansion, adjunctive treatment modalities, including orthognathic surgery, skeletal expansion and periodontal bone augmentation, be considered to prevent such dimensional changes.