Nevin Manimala

J Prosthet Dent. 2022 Sep 9:S0022-3913(22)00466-8. doi: 10.1016/j.prosdent.2022.07.005. Online ahead of print.

ABSTRACT

STATEMENT OF PROBLEM: When an abutment screw fractures, there is no standardized technique for retrieving it from the intaglio of the dental implant.

PURPOSE: The purpose of this in vitro study was to assess the relative efficacy of a commercially available screw fragment retrieval kit with a range of standard dental instruments in regard to success and retrieval time. In addition, the effects of other variables on the success rate of screw fragment retrieval and the retrieval time required were also investigated. Finally, the integrity of the intaglio screw channel of the dental implant was also assessed following retrieval.

MATERIAL AND METHODS: The abutment screws from 4 dental implant systems: Osseotite Certain, Ø4.1 mm (Zimmer Biomet); Osseotite External hexagonal connection micromini, Ø3.25 mm (Zimmer Biomet); Standard Plus Tissue Level, Ø4.8 mm (Institut Straumann AG); and Brånemark Mark III TiUnite, Ø4.1 mm (Nobel Biocare) had notches placed between the first and second coronal threads before being placed in their respective abutments, positioned in the dental implants (n=128), and tightened until the screws fractured. The dental implant specimens were placed in maxillary and mandibular casts at the lateral incisor and first molar sites on both sides. The casts were placed in mannequin heads on a dental chair and assigned to 2 experienced and 2 inexperienced operators who used 2 different retrieval kits to retrieve the screw fragments. Chisquared tests were used to determine the association between the success rate of screw fragment retrieval and the other factors recorded (α=.05), and a binary logistic regression was used to determine the association between the retrieval event and all of the independent variables. Regression models were developed to determine the factors effecting retrieval time.

RESULTS: An overall success rate of 88.3% was achieved for screw fragment retrieval. No statistically significant difference (P=1) was found in the relative efficacy of the retrieval kits. Univariate analysis identified a statistically significant association (P<.01) in the success of abutment screw fragment retrieval between the Osseotite Certain and the Osseotite External hexagonal connection micromini implant systems. Gamma regression analysis identified significant differences between the time taken to retrieve the screw fragments and the type of dental implant (P<.001), (P<.01). The time taken to retrieve screw fragments in the maxillary arch was significantly longer than for the mandibular arch (P<.05).

CONCLUSIONS: The commercially available screw fragment retrieval kit and the standard dental instruments were equally effective in retrieving the screw fragments. Less time was required to retrieve screw fragments in the mandibular arch than the maxillary arch. The level of experience of the operator had no effect on the ability to successfully retrieve fractured abutment screws.

PMID:36096913 | DOI:10.1016/j.prosdent.2022.07.005

J Prosthet Dent. 2022 Sep 9:S0022-3913(22)00339-0. doi: 10.1016/j.prosdent.2022.05.013. Online ahead of print.

ABSTRACT

STATEMENT OF PROBLEM: Clinical trials comparing outcomes associated with digital complete dentures (CDs) fabricated from intraoral scan data with those of CDs fabricated by using the conventional workflow are lacking.

PURPOSE: The purpose of this randomized clinical trial was to evaluate the clinical performance of and patient satisfaction associated with digitally versus conventionally fabricated CDs.

MATERIAL AND METHODS: Eight participants requiring CDs were enrolled in this study. Two sets of CDs were fabricated for each participant. One set was fabricated by using a digital workflow, which involved digital scanning with an intraoral scanner, whereas the other set was made by using the conventional workflow. The participants were given 1 set of CDs for 1 month and another set for the next month. The order of placing CDs was randomly selected for each participant. The internal adaptation, masticatory force, and masticatory efficiency of the CDs in each group were evaluated for objective analysis. Additionally, a questionnaire was provided to the participants, and the responses were evaluated for subjective satisfaction analysis. All parameters were analyzed by using t tests (α=.05).

RESULTS: The internal adaptation did not statistically significantly differ between the conventional and digital CDs with regard to the maxillary arches (P=.406) and mandibular arches (P=.412). The average masticatory force (P=.051) and maximum masticatory force (P=.110) likewise did not statistically significantly differ between the 2 types of CDs. Masticatory efficiency, expressed via the mixing ability index, was statistically better for conventional CDs than the digital CDs (P=.009). No statistically significant differences were observed between the 2 types of CDs in terms of overall patient satisfaction as assessed by using the study questionnaire (P=.172 for maxillary CD and P=.161 for mandibular CD). However, the conventional CDs were statistically significantly better than the digital CDs with regard to subjective satisfaction with pronunciation ability (P=.006).

CONCLUSIONS: The digital CDs were inferior to the conventional CDs in terms of masticatory efficiency and pronunciation. However, internal adaptation and overall patient satisfaction were comparable between conventional and digital CDs. This finding suggests that intraoral scanning and additively manufactured CDs may be suitable for edentulous patients, at least for interim use.

PMID:36096912 | DOI:10.1016/j.prosdent.2022.05.013

Ultrasound Med Biol. 2022 Sep 9:S0301-5629(22)00462-8. doi: 10.1016/j.ultrasmedbio.2022.06.010. Online ahead of print.

ABSTRACT

The aim of this study was to develop an eyewall curvature- and axial length (AxL)-based algorithm to automate detection (clinician-free) of staphyloma ridge and apex locations using ultrasound (US). Forty-six individuals (with emmetropia, high myopia or pathologic myopia) were enrolled in this study (AxL range: 22.3-39.3 mm), yielding 130 images in total. An intensity-based segmentation algorithm automatically tracked the posterior eyewall, calculating the posterior eyewall local curvature (K) and distance (L) to the transducer and the location of the staphyloma apex. By use of the area under the receiver operator characteristic (AUROC) curve to evaluate the diagnostic ability of eight local statistics derived from K, L and AxL, the algorithm successfully quantified non-uniformity of eye shape with an AUROC > 0.70 for most K-based parameters. The performance of binary classification (staphyloma absence vs. presence) was assessed with the best classifier (the combination of AxL, standard deviation of K and standard deviation of L) yielding a diagnostic validation performance of 0.897, which was comparable to the diagnostic performance of junior clinicians. The staphyloma apex was localized with an average error of 1.35 ± 1.34 mm. Combined with the real-time data acquisition capabilities of US, this method can be employed as a screening tool for clinician-free in vivo staphyloma detection.

PMID:36096896 | DOI:10.1016/j.ultrasmedbio.2022.06.010

Breast Cancer Res. 2022 Sep 12;24(1):61. doi: 10.1186/s13058-022-01556-6.

ABSTRACT

BACKGROUND: In clinical practice, oestrogen receptor (ER) analysis is almost entirely by immunohistochemistry (IHC). ASCO/CAP recommends cut-offs of < 1% (negative) and 1-10% (low) cells positive. There is uncertainty whether patients with ER low tumours benefit from endocrine therapy. We aimed to assess IHC and mRNA cut-points for ER versus biological response of primary breast cancer to 2 weeks’ aromatase inhibitor treatment as measured by change in Ki67.

METHODS: Cases were selected from the aromatase inhibitor treatment group of POETIC. We selected the 15% with the poorest Ki67 response (PR, < 40% Ki67 suppression, n = 230) and a random 30% of the remainder categorised as intermediate (IR, 40-79% Ki67 suppression, n = 150) and good-responders (GR, ≥ 80% Ki67 suppression, n = 230) from HER2 – group. All HER2 + cases available were selected irrespective of their response category (n = 317). ER expression was measured by IHC and qPCR.

RESULTS: ER IHC was available from 515 HER2 – and 186 HER2 + tumours and ER qPCR from 367 HER2 – and 171 HER2 + tumours. Ninety-one percentage of patients with ER IHC < 10% were PRs with similar rates in HER2 – and HER2 + cases. At or above ER IHC 10% substantial numbers of patients showed IR or GR. Similar proportions of patients were defined by cut-points of ER IHC < 10% and ER mRNA < 5 units. In addition, loss of PgR expression altered ER anti-proliferation response with 92% of PgR – cases with ER IHC < 40% being PRs.

CONCLUSIONS: There was little responsiveness at IHC < 10% and no distinction between < 1% and 1-10% cells positive. Similar separation of PRs from IR/GRs was achieved by IHC and mRNA.

PMID:36096872 | DOI:10.1186/s13058-022-01556-6

Reprod Biomed Online. 2022 Jun 26:S1472-6483(22)00431-X. doi: 10.1016/j.rbmo.2022.06.018. Online ahead of print.

ABSTRACT

RESEARCH QUESTION: Is there a relationship between embryo quality, pregnancy rates and apoptotic gene expression in cumulus cells of oocytes collected from patients with poor ovarian response and polycystic ovary syndrome?

DESIGN: Fifty infertile couples who underwent assisted reproductive technology treatment were included in the study (Approval date 4 February 2020, number 03). The patients were divided into four group: control (n = 9; 90 oocytes), unexplained infertility (n = 8; 86 oocytes), polycystic ovary syndrome (PCOS) (n = 6; 137 oocytes) and poor ovarian response (POR) (n = 27; 124 oocytes). Cumulus cells were isolated individually from 437 oocytes obtained. Intracytoplasmic sperm injection was undertaken on 365 mature oocytes. The embryos were monitored. Caspase-3, Bax and Bcl-2 gene expressions of the cumulus cells were measured by real-time polymerase chain reaction.

RESULTS: A significant and negative correlation was found between Bax and Bcl-2 expressions of the cumulus cells of poor-quality embryos. The increase in Caspase-3 gene expression in the POR group statistically decreases the pregnancy rates. Fertilization and good-quality embryo development of 365 oocytes whose cumulus cells were examined, however, were not associated with apoptotic gene expression. The Bax/Bcl-2 ratio was found to be significantly lower in cumulus cells of mature oocytes.

CONCLUSIONS: Our results demonstrated no significant associations between fertilization, quality embryo development and apoptotic gene expression. Bax expression and the Bax/Bcl-2 ratio are high in immature oocyte cumulus cells has shown us that the apoptotic process may begin when the cumulus-oocyte connection exists.

PMID:36096870 | DOI:10.1016/j.rbmo.2022.06.018

Eur J Surg Oncol. 2022 May 22:S0748-7983(22)00463-2. doi: 10.1016/j.ejso.2022.05.018. Online ahead of print.

ABSTRACT

BACKGROUND: Anastomotic leakage (AL) after colorectal surgery is well-researched, yet the effect of Hyperthermic Intraperitoneal Chemotherapy (HIPEC) after Cytoreductive Surgery (CRS) is unclear. Assessment of risk factors in these patients may assist surgeons during perioperative decision making.

METHODS: This was a single-center, retrospective study of patients who underwent CRS-HIPEC for colorectal peritoneal metastases. Main outcome measures were anastomotic leakage and associated morbidity.

RESULTS: AL was observed in 17 of the 234 (7.3%) anastomoses in 17 of the total of 165 (10.3%) of patients. No association was observed between the number and location of anastomoses and AL, although only one in 87 small bowel anastomoses showed leakage. The only factor associated with AL was administration of bevacizumab within 60 days prior to surgery with an odds ratio (OR) of 6.13 (1.32-28.39), P = 0.03. Deviating stomata were not statistically protective of increased morbidity, although more AL occurred in the patients with colocolic and colorectal anastomoses when no concomitant deviating stoma was created. Deviation stomata were reversed in 52.6%, and no AL was observed after stoma reversal.

CONCLUSION: The overall AL rate of CRS-HIPEC is comparable to colorectal surgery, and there is no cumulative risk of multiple anastomoses – especially in the case of small bowel anastomoses. Deviating stomata should be considered in patients with colocolic or colorectal anastomosis, although there is a significant chance that the stoma will not be reversed in these patients. Due to increased AL-risk surgeons should be aware of previous bevacizumab treatment, and plan the CRS-HIPEC at least 60 days after the treatment-day.

PMID:36096855 | DOI:10.1016/j.ejso.2022.05.018

Int J Urol. 2022 Sep 12. doi: 10.1111/iju.15036. Online ahead of print.

ABSTRACT

PURPOSE: To determine the efficacy and safety of trajectory infiltration with 1:150 000 Norepinephrine (NE) in reducing blood loss during percutaneous nephrolithotomy (PCNL).

MATERIALS AND METHODS: This is a prospective randomized double-blinded placebo-controlled trial. In all, 140 consecutive patients underwent PCNL for the management of large renal calculi. They were randomly assigned (1:1) to one of either study groups, the NE-PCNL group (70 patients whose PCNL-trajectory was infiltrated by NE) or the Placebo group (saline PCNL) (70 patients whose PCNL tracts were infiltrated by normal saline). Procedure-related blood loss (the primary outcome) was assessed and statistically analyzed. Also, all other procedure-related events and complications were recorded and compared.

RESULTS: The median blood loss was 378 ml (IQR: 252-504) in the NE-PCNL group versus 592 ml (IQR: 378-756) in the S-PCNL group (p < 0.0001). In addition, Hemoglobin and Hematocrit deficits were lower in NE-PCNL (p < 0.05). Patients who were randomized to the NE-PCNL group had a higher immediate stone-free rate (SFR) (80%) compared with those of the S-PCNL group (70%) (p = 0.034). However, no statistical differences were found in the final SFR. The reported overall complications between the 2 groups were similar (p > 0.05). Indeed, bleeding-related complications were 1 (1.4%) versus 10 (14.3%) for NE-PCNL and S-PCNL, respectively (p = 0.009).

CONCLUSIONS: Trajectory infiltration of PCNL tracts by NE was found to be effective and safe in mitigation of PCNL-related blood loss. This step is a timeless and cost-effective as NE is readily available in surgical theaters and of very low cost.

PMID:36094821 | DOI:10.1111/iju.15036

JMIR Med Educ. 2022 Sep 12;8(3):e37297. doi: 10.2196/37297.

ABSTRACT

BACKGROUND: Neonatal mortality accounts for approximately 46% of global under-5 child mortality. The widespread access to mobile devices in low- and middle-income countries has enabled innovations, such as mobile virtual reality (VR), to be leveraged in simulation education for health care workers.

OBJECTIVE: This study explores the feasibility and educational efficacy of using mobile VR for the precourse preparation of health care professionals in neonatal resuscitation training.

METHODS: Health care professionals in obstetrics and newborn care units at 20 secondary and tertiary health care facilities in Lagos, Nigeria, and Busia, Western Kenya, who had not received training in Helping Babies Breathe (HBB) within the past 1 year were randomized to access the electronic HBB VR simulation and digitized HBB Provider’s Guide (VR group) or the digitized HBB Provider’s Guide only (control group). A sample size of 91 participants per group was calculated based on the main study protocol that was previously published. Participants were directed to use the electronic HBB VR simulation and digitized HBB Provider’s Guide or the digitized HBB Provider’s Guide alone for a minimum of 20 minutes. HBB knowledge and skills assessments were then conducted, which were immediately followed by a standard, in-person HBB training course that was led by study staff and used standard HBB evaluation tools and the Neonatalie Live manikin (Laerdal Medical).

RESULTS: A total of 179 nurses and midwives participated (VR group: n=91; control group: n=88). The overall performance scores on the knowledge check (P=.29), bag and mask ventilation skills check (P=.34), and Objective Structured Clinical Examination A checklist (P=.43) were similar between groups, with low overall pass rates (6/178, 3.4% of participants). During the Objective Structured Clinical Examination A test, participants in the VR group performed better on the critical step of positioning the head and clearing the airway (VR group: 77/90, 86%; control group: 57/88, 65%; P=.002). The median percentage of ventilations that were performed via head tilt, as recorded by the Neonatalie Live manikin, was also numerically higher in the VR group (75%, IQR 9%-98%) than in the control group (62%, IQR 13%-97%), though not statistically significantly different (P=.35). Participants in the control group performed better on the identifying a helper and reviewing the emergency plan step (VR group: 7/90, 8%; control group: 16/88, 18%; P=.045) and the washing hands step (VR group: 20/90, 22%; control group: 32/88, 36%; P=.048).

CONCLUSIONS: The use of digital interventions, such as mobile VR simulations, may be a viable approach to precourse preparation in neonatal resuscitation training for health care professionals in low- and middle-income countries.

PMID:36094807 | DOI:10.2196/37297

Small. 2022 Sep 12:e2203234. doi: 10.1002/smll.202203234. Online ahead of print.

ABSTRACT

Air-channel devices have a special advantage due to the promise of vacuum-like ballistic transport in air, radiation insensitivity, and nanoscale size. Here, achieving high current at low voltage along with considerable mechanical stability is a primary issue. The comparative analysis of four planar and metallic electrode-pair geometries at 10 nm channel length is presented. The impact of nano-electrode-pair geometries on overall device performance is investigated. Air-channel devices are operated at the ultra-low voltage of 5 mV to demonstrate the device dynamics of air-channel devices at low power. Investigations focus on the direct tunneling (DT) mechanism which is dominant in the low-voltage regime. Comparative analysis of different electrode-pair geometries reveals two orders of magnitude increment in the current just by modulating the electrode-pair structure. Theoretical analysis suggests that the emission current is directly related to the active junction area within the metal-air-metal interface at the direct tunneling regime. The geometry-dependent mechanical stability of different electrode pairs is compared by imaging biasing triggered nanoscale structural changes and pulsed biasing stress analysis. The results and claims are confirmed and consolidated with the statistical analysis. Experimental investigations provide strong directions for high-performance and stable devices. In-depth theoretical discussions will enable the accurate modeling of emerging low-power, high-speed, radiation-hardened nanoscale vacuum electronics.

PMID:36094789 | DOI:10.1002/smll.202203234

Oral Radiol. 2022 Sep 12. doi: 10.1007/s11282-022-00655-6. Online ahead of print.

ABSTRACT

OBJECTIVES: The reasons why the maxillary posterior region is challenging for dentists are its structure and anatomical variations. For this reason, it is necessary to have complete knowledge about the anatomy of this region. In dentistry, necessary information for the desired evaluation in this region can be provided by CBCT. The fact that it provides a three-dimensional evaluation and has measurement reliability emphasizes its importance in surgical applications. The septa, haller cell, and accessory ostium are variations of the maxillary sinus. There are few studies in the literature examining the relationship between maxillary sinus diameters and its variations. The aims of this study are to determine the prevalence of maxillary sinus variations and the average of maxillary sinus diameters, to examine their relationships according to age and gender, and to evaluate the effects of maxillary sinus diameters on variations.

METHODS: In this retrospective study, CBCT images of 212 patients were examined. The examined CBCT images were analysed and recorded in more than one section. Descriptive statistics, chi-square tests, independent t test, one-way Anova tests were used to evaluate the data.

RESULTS: As a result, a statistically significant difference was observed between the variations, gender and age groups in terms of morphometric characteristics of the maxillary sinus. The most common variation was observed to be accessory ostium.

CONCLUSIONS: The rate of patients with at least one anatomical variation was 77.8%. For this reason, a detailed analysis should be performed to avoid complications before surgical procedures are performed in the area.

PMID:36094776 | DOI:10.1007/s11282-022-00655-6