Category: Statistics

Int J Oral Maxillofac Implants. 2021 Nov-Dec;36(6):1188-1197. doi: 10.11607/jomi.8994.

ABSTRACT

PURPOSE: This study investigated the impact of 0.12% chlorhexidine gluconate mouthwash on dental implants with periimplant mucositis and contralateral teeth with gingivitis at 6 months of follow-up after nonsurgical treatment.

MATERIALS AND METHODS: This was a secondary analysis of data from a previous controlled, randomized, double-blinded clinical trial of 30 patients diagnosed with peri-implant mucositis and gingivitis in contralateral teeth, at 6 months following treatment. Patients were randomly assigned into a test group (basic periodontal therapy + 0.12% chlorhexidine mouthwash) or a control group (basic periodontal therapy + placebo). Therapy consisted of an adaptation of the full-mouth scaling and root planing protocol. The clinical parameters of visible Plaque Index, Gingival Bleeding Index, probing depth, bleeding on probing, keratinized mucosa width, and gingival and peri-implant phenotype were evaluated at baseline and at 1, 3, and 6 months posttherapy. Data were analyzed using Poisson multilevel regression analysis with a significance level of .05.

RESULTS: The study analyzed 47 implants and contralateral teeth (376 sites) in the test group and 49 implants and contralateral teeth (392 sites) in the control group. No differences were found between the groups at the patient level. At the site level, the teeth and implants presented statistical differences in bleeding on probing, probing depth, and keratinized mucosa width at 3 months for both treatment groups. However, no difference was observed in bleeding on probing in the test group (P = .484) at 6 months, whereas the control group demonstrated increased bleeding on probing (indicating more inflammation) at implant sites than at teeth sites (P = .039). Additionally, implant sites with a thin peri-implant phenotype (P < .001) and located posteriorly (P = .002) presented greater inflammation.

CONCLUSION: Use of a 0.12% chlorhexidine mouthwash for 14 days was beneficial for implant sites with peri-implant mucositis, compared to contralateral teeth sites with gingivitis, as indicated by the reduced percentage of teeth with bleeding on probing.

PMID:34919620 | DOI:10.11607/jomi.8994

Int J Oral Maxillofac Implants. 2021 Nov-Dec;36(6):1159-1164. doi: 10.11607/jomi.8947.

ABSTRACT

PURPOSE: This study was conducted to compare the radiographic, esthetic, and patient-reported outcome measures (PROMs) between immediate and delayed restorations of immediately placed single implants in the maxillary esthetic zone.

MATERIALS AND METHODS: Forty patients with immediate single dental implants in the anterior maxilla were included in this study. Afterward, they were allocated either for immediate restoration with a provisional restoration (IR: 20 patients) or for a delayed restoration (DR: 20 patients). The evaluations were performed after 1 year of follow-up.

RESULTS: No implant and prosthetic failures were observed during the 1-year follow-up. Two minor complications were found in two IR patients; however, no complication was reported in the DR group during the 1 year. Nevertheless, this difference was not statistically significant (P > .05). After 1 year, the mean marginal bone level changes (MBL) were 0.47 ± 0.29 mm and 0.54 ± 0.21 mm for IR and DR, respectively. There was no statistically significant difference between the two groups in terms of MBL (P = .3). Notably, the mean total pink esthetic score (PES) and white esthetic score (WES) after 1 year of follow-up were 11.2 ± 1.1 (PES) and 8 ± 1.02 (WES) for the immediate restoration, and 10.2 ± 0.97 (PES) and 7.65 ± 1.20 (WES) for the delayed restoration. Also, no statistically significant difference was found between IR and DR in terms of esthetic scores (P > .05). The patient satisfaction of these two groups had no statistically significant difference, except for the esthetic factor (P = .04).

CONCLUSION: The immediate restoration and preferred esthetic satisfaction had similar outcomes compared with the delayed restoration.

PMID:34919616 | DOI:10.11607/jomi.8947

Int J Oral Maxillofac Implants. 2021 Nov-Dec;36(6):e159-e165. doi: 10.11607/jomi.8929.

ABSTRACT

PURPOSE: Conscious sedation in oral surgical procedures provides comfort both for patients and practitioners. Midazolam is a sedative agent commonly used in this manner. Dexmedetomidine is also a decent sedative agent, with its analgesic and mild respiratory effects, which is usually preferred in intensive care units. Dexmedetomidine has been recently used in dental surgeries. This study aimed to investigate the analgesic and respiratory properties of midazolam and dexmedetomidine in conscious sedation during dental implant procedures and to compare these two drugs in terms of ease of use and comfort of dental implant operation.

MATERIALS AND METHODS: This study was a prospective double-blind randomized controlled study. The patients who needed dental implant placement were divided into two randomized groups for either midazolam or dexmedetomidine. The amount of sedative agent used, duration of the procedure, onset of sedation, use of additional same sedative agent, and occurrence of desaturation were recorded. Hemodynamic and respiratory variables (mean blood pressure, heart rate, oxygen saturation, and respiratory rate) were recorded every 10 minutes, starting immediately before the loading dose until the end of the procedure. Patients completed a Likert scale for their satisfaction, and patient pain was scored using the numeric rating scale postoperatively. The amount of painkiller usage was recorded and reported. All surgical procedures were performed by the same surgeon, and all recordings were taken by an anesthesiology technician; both were blinded for the randomization. Descriptive and bivariate statistics were computed, and the P value was set at < .05.

RESULTS: This study included patients who were scheduled for two to five dental implant insertions to either arch under conscious sedation. A total of 163 dental implants were inserted into 43 patients. Patients receiving dexmedetomidine had lower pain, higher satisfaction with the procedure, and less desaturation (P = .002). The onset of sedation was more rapid with midazolam (P = .001). The number of implants according to drugs did not differ statistically. On the other hand, the mean operation time was 52.09 ± 20.12 minutes in the dexmedetomidine group and 87.14 ± 26.15 minutes in the midazolam group (P = .001). No significant difference was found for retrograde amnesia and preference of sedative between midazolam and dexmedetomidine.

CONCLUSION: Dexmedetomidine is a good alternative to midazolam for conscious sedation during dental implant procedures, with its better analgesic property and minimal respiratory side effects.

PMID:34919613 | DOI:10.11607/jomi.8929

Rev Med Inst Mex Seguro Soc. 2021 Sep 1;59(5):417-422.

ABSTRACT

BACKGROUND: Since the first cases of human immunodeficiency virus (HIV), ocular manifestations secondary to infection have been known and these have been related to the CD4+ lymphocyte count.

OBJECTIVE: To describe the correlation between ocular manifestations in patients with HIV and the CD4+ lymphocyte count.

MATERIAL AND METHODS: Analytical cross-sectional study of patients with HIV whose CD4+ count was correlated with the presence of ophthalmological manifestations.

RESULTS: 21 patients between 26 and 67 years were studied. Only 3 patients were not on antiretroviral therapy. 67% of the patients presented some type of ocular manifestation, 42% presented non-infection related manifestations, 47% related manifestations and 24% both. Conjunctival microangiopathy was the most frequent ocular manifestation (35.7%). There was a statistically significant correlation (r = 0.76, p = 0.0001) between eye manifestations related to infection and CD4+ lymphocyte count.

CONCLUSIONS: Patients with HIV frequently present ocular manifestations, the majority related to infection; there is a correlation between the presence of these with the CD4+ count. However, a similar number of manifestations not related to infection occurred without correlation with the count; therefore, HIV patients should have periodic ophthalmological examinations, independently of CD4+ count.

PMID:34918893

Rev Med Inst Mex Seguro Soc. 2021 Sep 1;59(5):423-430.

ABSTRACT

BACKGROUND: SARS-CoV-2 virus was notified by the World Health Organization in January 2020 as a global emergency, due to its intense transmission, and clinical picture, that is aggravated in susceptible people.

OBJECTIVE: To describe the factors associated with death in COVID-19 and pneumonia patients hospitalized in a thirdlevel center.

MATERIAL AND METHODS: An undivided case-control study was carried out. It was conducted an interview to obtain general information; from the medical record were collected hospitalization data, radiological images, laboratory parameters, and treatments used. It was used descriptive statistics. Student’s t, Mann-Whitney U, and chi-squared were used to identify variables associated with death, and models of adjusted binary logistic regression to propose which variables of the patient’s history, clinical parameters and treatments explained the death.

RESULTS: We treated 5339 patients with suspicion of COVID-19: 3117 positive (59%), 1029 hospitalized due to pneumonia, and 513 deaths (16.46%). For the analysis, 1110 patients were taken, 399 death cases were selected and 357 controls discharged due to improvement. The average age was 57.8 years; 59% were male.

CONCLUSIONS: The variables associated with mortality were: patients older than 40 years, chest radiography image > 50% involvement, intubation, lactic dehydrogenase > 500, C-reactive protein > 10, and organ failure; variables associated with improvement were: stay in the intensive care unit, use of broad spectrum parenteral antibiotics, steroids, and use of the anticoagulant enoxyheparin. Sex, diabetes, and comorbidities did not show significant association.

PMID:34918895

Adv Clin Exp Med. 2021 Dec 17. doi: 10.17219/acem/143586. Online ahead of print.

ABSTRACT

BACKGROUND: Behçet’s disease (BD) is a chronic inflammatory vasculitis affecting multiple organs. Uveitis is frequently seen in patients with BD, especially in Turkish population.

OBJECTIVES: To investigate vascular endothelial growth factor (VEGF) gene polymorphisms along with the levels of VEGF and VEGF receptors in patients with Behçet’s uveitis (BU).

MATERIAL AND METHODS: Fifty-five BD-associated uveitis patients and 30 ageand sex-matched controls were included in this case-control study. The genotypes of the single nucleotide poymorphisms (SNPs): rs2010963 (+405G), rs3025039 (+936T) and rs699947 (-2598A) of the VEGF-A gene were determined using real-time polymerase chain reaction (RT-PCR) and serum levels of VEGF and VEGF receptors were measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS: No associations of the VEGF gene polymorphisms were observed in BD uveitis patients, but arthritis was present in 53.3% of patients not possessing CT genotype in C3025039→T polymorphism (p = 0.024). Although there were no statistically significant differences in serum VEGF-A, VEGF-C and soluble vascular endothelial growth factor receptor-3 (sVEGFR-3) levels (p < 0.05), serum vascular endothelial growth factor receptor-1 (VEGFR-1) and sVEGFR-3 levels were significantly higher in the BD group (p < 0.001 and p = 0.001, respectively). In addition, VEGF-C/soluble vascular endothelial growth factor receptor-2 (sVEGFR-2) ratio was significantly higher (p < 0.001), while VEGF-A/VEGFR-1 and VEGF-C/sVEGFR-3 ratios were significantly lower (p < 0.001 and p = 0.033, respectively) in BD patients compared to controls. Also, VEGF-C/sVEGFR-3 (p = 0.024, r = 0.37) and VEGF-C/sVEGFR-2 (p = 0.020, r = 0.38) ratios were positively correlated with disease duration.

CONCLUSIONS: The significant changes in sVEGFR-3 levels and VEGF-C/sVEGFR-3 ratio has shown that lymphangiogenesis processes might take place in the pathogenesis of BD uveitis, and these parameters can be important indicators of evaluation of BD patients with uveitis together with disease duration.

PMID:34918882 | DOI:10.17219/acem/143586

Rev Med Inst Mex Seguro Soc. 2021 Sep 1;59(5):404-411.

ABSTRACT

BACKGROUND: The pandemic caused by COVID-19 is one of the main problems of public health around the world. Of the individuals with infection, a large amount corresponds to first-level health workers.

OBJECTIVE: To determine the relationship between length of stay in respiratory offices and SARS-CoV-2 infection in health workers at a first-level health center.

MATERIAL AND METHODS: Cross-sectional analytic study in health workers of a first-level unit of San Luis Potosí, Mexico, who developed suspected symptomatology of SARS-CoV-2 infection from March 2020 to January 2021. Two groups were formed according to the result of the RT-PCR. Demographic variables, occupation, work area, work in respiratory area, hours of work accumulated within the respiratory area to develop symptomatology, and date of development of symptomatology were registered.

RESULTS: Of 350 health workers active, 144 developed respiratory symptomatology; of these, 66 had positive RT-PCR for SARS-CoV-2 infection. Working in an area with no respiratory patients but in contact with other patients confers an OR 2.49 (1.04-6.26), when compared with working in a respiratory area, p 0.0446. The length in a filter for respiratory patients gives a protective OR of 0.3062 (0.08-0.99) for developing SARS-CoV-2 infection, p 0.0608. Each hour accumulated in a respiratory area confers an OR 1.001 (0.99-1.00) without statistical significance, p 0.3046.

CONCLUSIONS: Working in a respiratory area and the accumulated hours of work in this place are not risk factors for developing COVID-19 in health workers.

PMID:34918890

J Appl Clin Med Phys. 2021 Dec 17. doi: 10.1002/acm2.13508. Online ahead of print.

ABSTRACT

PURPOSE: Methodologies for optimization of SPECT image acquisition can be challenging due to imaging throughput, physiological bias, and patient comfort constraints. We evaluated a vendor-independent method for simulating lower count image acquisitions.

METHODS: We developed an algorithm that recombines the ECG-gated raw data into reduced counting acquisitions. We then tested the algorithm to simulate reduction of counting statistics from phantom SPECT image acquisition, which was synchronized with an ECG simulator. The datasets were reconstructed with a resolution recovery algorithm and the summed stress score (SSS) was assessed by three readers (two experts and one automatic).

RESULTS: The algorithm generated varying counting levels, simulating multiple examinations at the same time. The error between the expected and the simulated countings ranged from approximately 5% to 10% for the ungated simulations and 0% for the gated simulations.

CONCLUSIONS: The vendor-independent algorithm successfully generated lower counting statistics datasets from single-gated SPECT raw data. This method can be readily implemented for optimal SPECT research aiming to lower the injected activity and/ or to shorten the acquisition time.

PMID:34918865 | DOI:10.1002/acm2.13508

Br J Math Stat Psychol. 2021 Dec 17. doi: 10.1111/bmsp.12261. Online ahead of print.

ABSTRACT

The aim of latent variable selection in multidimensional item response theory (MIRT) models is to identify latent traits probed by test items of a multidimensional test. In this paper the expectation model selection (EMS) algorithm proposed by Jiang et al. (2015) is applied to minimize the Bayesian information criterion (BIC) for latent variable selection in MIRT models with a known number of latent traits. Under mild assumptions, we prove the numerical convergence of the EMS algorithm for model selection by minimizing the BIC of observed data in the presence of missing data. For the identification of MIRT models, we assume that the variances of all latent traits are unity and each latent trait has an item that is only related to it. Under this identifiability assumption, the convergence of the EMS algorithm for latent variable selection in the multidimensional two-parameter logistic (M2PL) models can be verified. We give an efficient implementation of the EMS for the M2PL models. Simulation studies show that the EMS outperforms the EM-based L₁ regularization in terms of correctly selected latent variables and computation time. The EMS algorithm is applied to a real data set related to the Eysenck Personality Questionnaire.

PMID:34918834 | DOI:10.1111/bmsp.12261

Mol Ecol. 2021 Dec 17. doi: 10.1111/mec.16329. Online ahead of print.

ABSTRACT

Selection leaves signatures in the DNA sequence of genes, with many test statistics devised to detect its action. While these statistics are frequently used to support hypotheses about the adaptive significance of particular genes, the effect these genes have on reproductive fitness is rarely quantified experimentally. Consequently, it is unclear how gene-level signatures of selection are associated with empirical estimates of gene effect on fitness. Eukaryotic datasets that permit this comparison are very limited. Using the model plant Arabidopsis thaliana, for which these resources are available, we calculated seven gene-level substitution and polymorphism-based statistics commonly used to infer selection (dN/dS, NI, DOS, Tajima’s D, Fu and Li’s D*, Fay and Wu’s H, and Zeng’s E) and, using knockout lines, compared these to gene-level estimates of effect on fitness. We found that consistent with expectations, essential genes were more likely to be classified as negatively selected. By contrast, using 379 Arabidopsis genes for which data was available, we found no evidence that genes predicted to be positively selected had a significantly different effect on fitness than genes evolving more neutrally. We discuss these results in the context of the analytic challenges posed by Arabidopsis, one of the only systems in which this study could be conducted, and advocate for examination in additional systems. These results are relevant to the evaluation of genome-wide studies across species where experimental fitness data is unavailable, as well as highlighting an increasing need for the latter.

PMID:34918851 | DOI:10.1111/mec.16329