Machine Learning-Enabled NIR Spectroscopy. Part 3: Hyperparameter by Design (HyD) Based ANN-MLP Optimization, Model Generalizability, and Model Transferability.

Data variations, library changes, and poorly tuned hyperparameters can cause failures in data-driven modelling. In such scenarios, model drift, a gradual shift in model performance, can lead to inaccurate predictions. Monitoring and mitigating drift are vital to maintain model effectiveness. USFDA and ICH regulate pharmaceutical variation with scientific risk-based approaches. In this study, the hyperparameter optimization for the Artificial Neural Network Multilayer Perceptron (ANN-MLP) was investigated using open-source data. The design of experiments (DoE) approach in combination with target drift prediction and statistical process control (SPC) was employed to achieve this objective. First, pre-screening and optimization DoEs were conducted on lab-scale data, serving as internal validation data, to identify the design space and control space. The regression performance metrics were carefully monitored to ensure the right set of hyperparameters was selected, optimizing the modelling time and storage requirements. Before extending the analysis to external validation data, a drift analysis on the target variable was performed. This aimed to determine if the external data fell within the studied range or required retraining of the model. Although a drift was observed, the external data remained well within the range of the internal validation data. Subsequently, trend analysis and process monitoring for the mean absolute error of the active content were conducted. The combined use of DoE, drift analysis, and SPC enabled trend analysis, ensuring that both current and external validation data met acceptance criteria. Out-of-specification and process control limits were determined, providing valuable insights into the model's performance and overall reliability. This comprehensive approach allowed for robust hyperparameter optimization and effective management of model lifecycle, crucial in achieving accurate and dependable predictions in various real-world applications.

Effectiveness of hyperbaric oxygen therapy in irradiated maxillofacial dental implant patients: A systematic review with meta-analysis.

The significantly higher implant failure rates in maxillofacial patients, undergoing radiotherapy, might be caused by the long-term effects of reduced vascularization compromising the implantation site. An extensive preclinical animal literature and a multitude of clinical reports suggest the use of hyperbaric oxygen (HBO) therapy as it can improve the tissue vascularity. Hence, it may increase the implant survival rate by enhancing osseointegration process in such patients. The objective of this systematic review was to investigate the effectiveness of HBO therapy on dental implant survival rate in irradiated maxillofacial patients who require prosthodontic rehabilitation. An electronic search without time restrictions was undertaken in April 2016 using databases: PubMed, Google Scholar, and the Cochrane Oral Health Group Trials Register. We also tried to contact the manufacturers and researchers in the field for necessary details. Clinical human studies, on irradiated maxillofacial dental implant patients, including randomized controlled trials (RCTs), prospective controlled trials, retrospective studies, and preliminary reports were included in the study. Data collection was carried out by two of the authors' independently. The titles and abstracts of all reports were screened for the study design and type of reported intervention; all the duplicates were removed. The data search yielded 62 titles, out of which 14 articles were selected for the study by the article filtration criteria: Title/abstract/full text. Data which were extracted by two authors with any disagreement were resolved by the third author, and a meta-analysis was done using binary random-effect model. The results show decreased implant failure rate in HBO group (9.21%) compared to non-HBO group (22.44%). The potential limitations of this study are amount of radiation doses used, period lasting from radiotherapy to the placement of the implants, and follow-up period which varies for every subject of the included study, which can affect the treatment outcome. Although there are many sensitive articles published about HBO, including a number of review papers, RCTs are still lacking. According to the statistical analysis, it can be concluded that preventive HBO therapy can reduce the risk of implant failures in irradiated patients by 1.21 (relative risk) with 95% confidence interval (P < 0.001). Hence, HBO can be the effective treatment protocol for the implant treatment in irradiated maxillofacial patients.

Evaluation of flexural strength and color stability of different denture base materials including flexible material after using different denture cleansers.

AIMS: Present study aimed at evaluating the colour stability and flexural strength of flexible denture base materials (Valplast) and Polymethyl methacrylate (PMMA) denture base material (Meliodent) processed by two different methods (Injection moulding and compression moulding) after immersing them in three different denture cleansers with acidic, basic and neutral PH. METHODS AND MATERIALS: Total 120 specimens (65 × 10 × 3 mm3), 40 specimens of each material (Valplast, Meliodent compression moulding and injection moulding) were immersed in denture cleansers having different PH; Valclean (Acidic), Clinsodent (Basic) and Polident (Neutral) as well as Distilled Water. Color changes were measured with a spectrophotometer after 1 month, 3 months and 6 months of immersion cycle. A flexural 3-point bending test was carried out by using an Instron universal testing machine after 6 months of soaking. Data were analyzed using SPSS software. RESULTS: Maximum effect on colour stability was noted with Clinsodent followed by Valclean. Least color changes were observed after immersion in Polident. Colour difference was increased significantly as the immersion time increased. For both Meliodent and Nylon resins, statistically significant change in flexural strength occurred with immersion in all denture cleansers. Clinsodent has greater effect as compared to Valclean and Polident. CONCLUSIONS: Polident and Valclean can be safely used as denture cleanser for both nylon and acrylic resin denture base materials as far as colour stability and flexural strength both are concerned.

Survival rate of dental implant placed using various maxillary sinus floor elevation techniques: A systematic review and meta-analysis.

Aim: The aim of this systematic review is to evaluate the survival rate of dental implant placed using different maxillary sinus floor elevation techniques. Setting and Design: PRISMA guidelines were used for this systematic review and meta-analysis. Materials and Methods: Relevant articles were searched from Medline, PubMed, Google Scholar, ScienceDirect, and Cochrane trials. Articles published in English language were selected. Hand search was further conducted. For risk of bias, two tools were used, i.e., Cochrane tool for randomized controlled trials (RCTs) and new castle Ottawa quality assessment tool for non-RCTs. Statistical Analysis: For statistical meta-analysis RevMan 5.4 software was used. Results: Seventeen studies were finalized. All studies were included in the meta-analysis to check the implant survival rate. There is no statistical difference between direct and indirect techniques, and forest plot was derived for direct approach (P = 0.688, 95% confidence interval [CI] 0.9691) and for indirect approach (P = 0.686 and 95% CI 0.970). Conclusion: There is no statistically significant difference in the survival rate of implant placed using direct or indirect sinus lift approach procedures. Hence, the technique is selected as per the indications given for each direct and indirect procedure.

Various bio-mechanical factors affecting heat generation during osteotomy preparation: A systematic review.

BACKGROUND: As implant site preparation and bone are critical precursors to primary healing, thermal and mechanical damage to the bone must be minimized during the preparation of the implant site. Moreover, excessively traumatic surgery can adversely affect the maturation of bone tissue at the bone/implant interface and consequently diminish the predictability of osseointegration. So, this study was carried out to evaluate the various biological and mechanical factors responsible for heat generation during osteotomy site preparation to reduce the same for successful osseointegration of dental implants. STUDY DESIGN: A broad search of the dental literature in PubMed added by manual search was performed for articles published between 1992 and December 2015. Various bio-mechanical factors related to dental implant osteotomy preparation such as dental implant drill designs/material/wear, drilling methods, type of irrigation, and bone quality were reviewed. Titles and abstracts were screened and articles which fulfilled the inclusion criteria were selected for a full-text reading. RESULTS: The initial database search yielded 123 titles, of which 59 titles were discarded after reading the titles and abstracts, 30 articles were again excluded based on inclusion and exclusion criteria, and finally 34 articles were selected for data extraction. Many biological and mechanical factors responsible for heat generation were found. CONCLUSION: Literatures of this review study have indicated that there are various bio-mechanical reasons, which affect the temperature rise during osteotomy and suggest that the amount of heat generation is a multifactorial in nature and it should be minimized for better primary healing of the implant site.