Chia-Ling Kuo

Prospective cohort pilot study of 2-visit CAD/CAM monolithic complete dentures and implant-retained overdentures: Clinical and patient-centered outcomes

STATEMENT OF PROBLEM Presently, no studies have evaluated clinical outcomes or patient-centered outcomes for complete dentures fabricated with computer-aided design and computer aided manufacturing (CAD/CAM) technology. PURPOSE The purpose of this prospective cohort pilot study was to evaluate the clinical and patient-centered outcomes for CAD/CAM monolithic dentures fabricated in 2 visits. MATERIAL AND METHODS Twenty participants with an existing set of maxillary complete dentures opposing either mandibular complete dentures or implant-retained overdentures that required replacement were recruited in this study. A 2-visit duplicate denture protocol was used to fabricate 40 arches of monolithic dentures with CAD/CAM technology. A 100-mm visual analog scale (VAS) instrument was then used to record 12 outcomes at baseline and at 1-year follow-up. Predetermined values were assigned to grade the VAS rating of each outcome as favorable (70.1-100) and unfavorable (≤70). Favorable ratings were sub-divided as excellent (90.1-100), good (80.1-90), and fair (70.1-80). The clinical outcomes were evaluated independently by 2 experienced prosthodontists at baseline and at 1-year follow-up. Patients evaluated the corresponding patient-centered outcomes during the same time intervals. Additional descriptive variables were also recorded. Each clinical and patient-centered outcome was summarized by medians and ranges. Differences in all ratings recorded at baseline and at 1 year were tested by 1-sided sign test (α=.05). RESULTS Of 20 participants, 3 were lost to follow-up, and 3 were unsatisfied with the digital dentures and withdrew from the study. These 3 participants were considered treatment failures. Of the 14 remaining participants, 9 had implant-retained mandibular overdentures, and 5 had conventional mandibular complete dentures. For clinical outcomes, the 12 studied outcomes were favorably evaluated by the 2 prosthodontist judges at the 1-year follow-up. Evaluations showed minimal differences between baseline and 1 year. An average of 5 emails (0-11) per patient were sent to the laboratory technicians to communicate the improvisation the CAD design of the dentures. An average of 3.3 denture adjustments were needed after insertion (0-10) during the 1-year period. For patient-centered outcomes, median ratings of all 14 participants indicated each of the 12 studied outcomes was favorable at the 1-year recall. Statistically significant improvements in patient ratings from baseline to 1 year were observed for the absence of denture sore spots and treatment time to make the dentures (P<.05). Minor complications related to loss of retention, excessive wear of teeth and the need for additional visits were observed in 5 participants. No other adverse clinical outcomes related to the CAD/CAM dentures were noted in the 14 evaluated participants, and all dentures were intact and in good condition at the 1-year follow-up. CONCLUSIONS Clinical and patient-centered outcomes for CAD/CAM monolithic dentures fabricated using a 2-visit protocol were evaluated favorably at a 1-year follow-up. However, the proportion of excellent and good ratings for overall satisfaction and assessment was higher for patients than clinicians. A considerable amount of the clinicians time and effort was devoted to aiding in the digital process for the fabrication of CAD/CAM dentures.

Neck recurrence and mortality in esthesioneuroblastoma: Implications for management of the N0 neck

To review the literature on neck recurrence in esthesioneuroblastoma.

Biodegradable Piezoelectric Force Sensor.

Significance Measuring physiological pressures such as lung pressure, brain pressure, eye pressure, etc. is important for monitoring health status, preventing the buildup of dangerous internal forces in impaired organs, and enabling novel approaches of using mechanical stimulation for tissue regeneration. Pressure sensors are often implanted and directly integrated with soft biological systems. Therefore, the devices should be flexible and at the same time biodegradable to avoid invasive removal surgery. Here, we present the study and processing of a biodegradable polymer which can convert mechanical force to electricity, and employ the polymer to develop a biocompatible implanted force sensor. The sensor, relying solely on common medical materials, can monitor important biological forces and eventually self-vanish, causing no harm to the body. Measuring vital physiological pressures is important for monitoring health status, preventing the buildup of dangerous internal forces in impaired organs, and enabling novel approaches of using mechanical stimulation for tissue regeneration. Pressure sensors are often required to be implanted and directly integrated with native soft biological systems. Therefore, the devices should be flexible and at the same time biodegradable to avoid invasive removal surgery that can damage directly interfaced tissues. Despite recent achievements in degradable electronic devices, there is still a tremendous need to develop a force sensor which only relies on safe medical materials and requires no complex fabrication process to provide accurate information on important biophysiological forces. Here, we present a strategy for material processing, electromechanical analysis, device fabrication, and assessment of a piezoelectric Poly-l-lactide (PLLA) polymer to create a biodegradable, biocompatible piezoelectric force sensor, which only employs medical materials used commonly in Food and Drug Administration-approved implants, for the monitoring of biological forces. We show the sensor can precisely measure pressures in a wide range of 0–18 kPa and sustain a reliable performance for a period of 4 d in an aqueous environment. We also demonstrate this PLLA piezoelectric sensor can be implanted inside the abdominal cavity of a mouse to monitor the pressure of diaphragmatic contraction. This piezoelectric sensor offers an appealing alternative to present biodegradable electronic devices for the monitoring of intraorgan pressures. The sensor can be integrated with tissues and organs, forming self-sensing bionic systems to enable many exciting applications in regenerative medicine, drug delivery, and medical devices.

Red blood cell distribution width: Genetic evidence for aging pathways in 116,666 volunteers

Introduction Variability in red blood cell volumes (distribution width, RDW) increases with age and is strongly predictive of mortality, incident coronary heart disease and cancer. We investigated inherited genetic variation associated with RDW in 116,666 UK Biobank human volunteers. Results A large proportion RDW is explained by genetic variants (29%), especially in the older group (60+ year olds, 33.8%, <50 year olds, 28.4%). RDW was associated with 194 independent genetic signals; 71 are known for conditions including autoimmune disease, certain cancers, BMI, Alzheimer’s disease, longevity, age at menopause, bone density, myositis, Parkinson’s disease, and age-related macular degeneration. Exclusion of anemic participants did not affect the overall findings. Pathways analysis showed enrichment for telomere maintenance, ribosomal RNA, and apoptosis. The majority of RDW-associated signals were intronic (119 of 194), including SNP rs6602909 located in an intron of oncogene GAS6, an eQTL in whole blood. Conclusions Although increased RDW is predictive of cardiovascular outcomes, this was not explained by known CVD or related lipid genetic risks, and a RDW genetic score was not predictive of incident disease. The predictive value of RDW for a range of negative health outcomes may in part be due to variants influencing fundamental pathways of aging.

Clinical Factors Affecting the Accuracy of Guided Implant Surgery—A Systematic Review and Meta-analysis

Objectives To systematically review the current dental literature regarding clinical accuracy of guided implant surgery and to analyze the involved clinical factors. Material and Methods PubMed and Cochrane Central Register of Controlled Trials were searched. Meta‐analysis and meta‐regression analysis were performed. Clinical studies with the following outcome measurements were included: (1) angle deviation, (2) deviation at the entry point, and (3) deviation at the apex. The involved clinical factors were further evaluated. Results Fourteen clinical studies from 1951 articles initially identified met the inclusion criteria. Meta‐regression analysis revealed a mean deviation at the entry point of 1.25 mm (95% confidence interval [CI]: 1.22‐1.29), 1.57 mm (95% CI: 1.53‐1.62) at the apex, and 4.1° in angle (95% CI: 3.97‐4.23). A statistically significant difference (P < .001) was observed in angular deviations between the maxilla and mandible. Partially guided surgery showed a statistically significant greater deviation in angle (P < .001), at the entry point (P < .001), and at the apex (P < .001) compared with totally guided surgery. The outcome of guided surgery with flapless approach indicated significantly more accuracy in angle (P < .001), at the entry point (P < .001), and at apex (P < .001). Significant differences were observed in angular deviation based on the use of fixation screw (P < .001). Conclusions The position of guide, guide fixation, type of guide, and flap approach could influence the accuracy of computer‐aided implant surgery. A totally guided system using fixation screws with a flapless protocol demonstrated the greatest accuracy. Future clinical research should use a standardized measurement technique for improved accuracy.

Unconditional or Conditional Logistic Regression Model for Age-Matched Case–Control Data?

Matching on demographic variables is commonly used in case–control studies to adjust for confounding at the design stage. There is a presumption that matched data need to be analyzed by matched methods. Conditional logistic regression has become a standard for matched case–control data to tackle the sparse data problem. The sparse data problem, however, may not be a concern for loose-matching data when the matching between cases and controls is not unique, and one case can be matched to other controls without substantially changing the association. Data matched on a few demographic variables are clearly loose-matching data, and we hypothesize that unconditional logistic regression is a proper method to perform. To address the hypothesis, we compare unconditional and conditional logistic regression models by precision in estimates and hypothesis testing using simulated matched case–control data. Our results support our hypothesis; however, the unconditional model is not as robust as the conditional model to the matching distortion that the matching process not only makes cases and controls similar for matching variables but also for the exposure status. When the study design involves other complex features or the computational burden is high, matching in loose-matching data can be ignored for negligible loss in testing and estimation if the distributions of matching variables are not extremely different between cases and controls.

Assessing the Probability that a Finding Is Genuine for Large-Scale Genetic Association Studies

Genetic association studies routinely involve massive numbers of statistical tests accompanied by P-values. Whole genome sequencing technologies increased the potential number of tested variants to tens of millions. The more tests are performed, the smaller P-value is required to be deemed significant. However, a small P-value is not equivalent to small chances of a spurious finding and significance thresholds may fail to serve as efficient filters against false results. While the Bayesian approach can provide a direct assessment of the probability that a finding is spurious, its adoption in association studies has been slow, due in part to the ubiquity of P-values and the automated way they are, as a rule, produced by software packages. Attempts to design simple ways to convert an association P-value into the probability that a finding is spurious have been met with difficulties. The False Positive Report Probability (FPRP) method has gained increasing popularity. However, FPRP is not designed to estimate the probability for a particular finding, because it is defined for an entire region of hypothetical findings with P-values at least as small as the one observed for that finding. Here we propose a method that lets researchers extract probability that a finding is spurious directly from a P-value. Considering the counterpart of that probability, we term this method POFIG: the Probability that a Finding is Genuine. Our approach shares FPRPs simplicity, but gives a valid probability that a finding is spurious given a P-value. In addition to straightforward interpretation, POFIG has desirable statistical properties. The POFIG average across a set of tentative associations provides an estimated proportion of false discoveries in that set. POFIGs are easily combined across studies and are immune to multiple testing and selection bias. We illustrate an application of POFIG method via analysis of GWAS associations with Crohns disease.

Evaluation of the donor cell contribution in rhBMP-2 mediated bone formation with chitosan thermogels using fluorescent protein reporter mice.

Our current understanding regarding the contribution of donor cells in growth factor and cell based tissue regeneration strategies is limited. The present study attempts to utilize fluorescent protein reporter mice [Col3.6Topaz (enhanced yellow fluorescent protein, EYFP) as host and Col3.6Cyan (enhanced cyan fluorescent protein, ECFP) as donor] to determine donor cell contribution in bone regeneration using a bilateral calvarial defect model. Thermogelling chitosan hydrogels (Chi-AHP) were used as bone marrow stromal cell (BMSC) delivery vehicle in the presence and absence of recombinant human bone morphogenetic protein-2 (rhBMP-2). Co-delivery of rhBMP-2 and donor BMSCs led to a significant increase in bone formation indicating the potential of using the combination approach for improved regeneration. On a cellular level, presence of rhBMP-2 resulted in an increased host cell derived osteoblast infiltration at 8 weeks. However, the new mineralized tissue presented two distinct morphological features based on its cellular origin. Regenerated tissue associated with ECFP positive donor cells showed a woven bone-like structure with diffuse alizarin complexone (AC) label and minimal tartrate resistant acid phosphatase (TRAP) activity, indicating the presence of immature early osteoblast cells depositing mineralized tissue without progressing to a mature lamellar bone. Host derived bone showed sharp mineralization line (AC), strong alkaline phosphatase (ALP) and TRAP activity, indicating the presence of actively mineralizing and remodeling, mature lamellar bone matrix. The study demonstrated the remarkable potential of transgenic reporters to improve our understanding of donor cell contribution during bone formation.

Opioid Prescribing Patterns among Otolaryngologists

Objectives To evaluate national trends in opioid prescribing patterns by otolaryngologists for postoperative pain control after common otolaryngologic procedures. Study Design Cross-sectional; survey. Subjects and Methods A survey to determine opioid prescribing patterns for the treatment of postoperative pain following common otolaryngologic procedures was distributed to all members of the American Academy of Otolaryngology–Head and Neck Surgery. Results The most common pain medication prescribed for adults postoperatively was hydrocodone-acetaminophen (73%), followed by oxycodone-acetaminophen (39%). The most common pain medication prescribed postoperatively for children was acetaminophen (67%), followed by nonsteroidal anti-inflammatory drugs (65%). Overall, there was a wide variation in quantity of opioids prescribed for each surgery, ranging from 0 to more than 60 doses. Mean opioid prescriptions were greatest for tonsillectomy (37 tablets) and least for direct laryngoscopy (5.3 tablets). Conclusion This study identifies nationwide variations in opioid prescribing patterns among otolaryngologists. While otolaryngology is a relatively small specialty, we still have an obligation to work with all physicians to help combat the current opioid epidemic. By evaluating nationwide postoperative pain regimens, we are moving closer toward understanding how to reduce the opioid burden.

Differences in Lip Support with and without Labial Flanges in a Maxillary Edentulous Population – Part 3: Unblinded and Discriminatory Subjective Analysis

PURPOSE To study the subjective differences in direct lip support assessments and to determine if dentists and laypeople are able to discern and correctly identify direct changes in lip support between flange and flangeless dentures. MATERIALS AND METHODS A random sample of 20 maxillary edentulous patients described in part 2 of the study was used for analysis. A total of 60 judges comprising 15 general dentists, 15 prosthodontists, and 30 laypeople, the majority of who were distinct from part 2 of the study, were recruited. All images used in this study were cropped at the infraorbital level and converted to black and white tone, to encourage the judges to focus on lip support. The judges were un-blinded to the study objectives and told what to look for, and were asked to rate the lip support of each of the 80 images on a 100 mm visual analog scale (VAS). The judges then took a discriminatory sensory analysis test (triangle test) where they were required to correctly identify the image with a flangeless denture out of a set of 3 images. Both the VAS and triangle test ratings were conducted twice in a random order, and mean ratings were used for all analyses. RESULTS The overall VAS ratings of lip support for images with flangeless dentures were slightly lower compared to images with labial flanges, and this difference was statistically significant (p < 0.0001). This was true for both profile and frontal images. However, the magnitude of these differences was too small (no greater than 5 mm on a 100-mm scale) to be clinically significant or meaningful. The differences in VAS ratings were not significant between the judges. For the triangle test, judges overall correctly identified the flangeless denture image in 55% of frontal image sets and 60% of profile image sets. The difference in correct identification rate between frontal and profile images was statistically significant (p < 0.0001). For frontal and profile images, prosthodontists had the highest correct identification rate (61% and 69%), followed by general dentists (53% and 68%) and by laypeople (53% and 50%). The difference in correct identification rate was statistically significant between various judges (p = 0.012). For all judges, the likelihood of correctly identifying images with flangeless dentures was significantly greater than 1/3, which was the minimum chance for correct identification (p < 0.0001). CONCLUSIONS Removal of a labial flange in a maxillary denture resulted in slightly lower ratings of lip support compared to images with a labial flange, but the differences were clinically insignificant. When judges were forced to look for differences, flangeless dentures were detected more often in profile images. Prosthodontists detected the flangeless dentures more often than general dentists and laypeople.