Strengthening effect of flavonoid antioxidant on resin-enamel bond strength following tooth bleaching

This study aimed to assess the impact of flavonoid-based antioxidant application after in-office bleaching with 35% hydrogen peroxide on the shear bond strength of resin to bovine enamel, comparing it with 10% sodium ascorbate. Bovine enamel blocks (n = 10) were randomly assigned to one of five pretreatments: (i) no bleaching, (ii) bleaching without antioxidant application, and (iii) bleaching followed by a 1-min application of 10% sodium ascorbate, (iv) 5% naringin, or (v) 10% naringin. Color analysis was conducted using a digital spectrophotometer. Shear bond strength was assessed on two, 2-mm-diameter resin cylinders per block using a universal testing machine at 0.5 mm/min until fracture. Enamel surface morphology was analyzed using scanning electron microscopy. Shear bond strength values and color parameters (ΔEab, ΔE00, and ΔWID) were analyzed using one-way ANOVA, while t-tests were used for the individual color parameters lightness (L*), green-red (a*), blue-yellow (b*), and chroma (C*) . None of the antioxidants resulted in bond strength values as high as those observed without bleaching. However, application of sodium ascorbate and 5% naringin after bleaching significantly increased bond strength compared with bleached enamel without antioxidant. Antioxidants had no significant impact on color. The predominant failure modes were adhesive between the adhesive and enamel, and mixed.

Prevalence and morphometric evaluation of dilaceration in Indian Tamils: an analysis of 10,089 permanent teeth

AIM

The present radiographic study was conducted to assess the subject and tooth prevalence of dilaceration in a cohort of Tamil population aided by morphometric analysis.

MATERIALS AND METHODS

After obtaining clearance from institutional human ethical clearance committee, 575 panoramic radiographs were retrieved. After exclusion of 233 radiographs based on the inclusion and exclusion criteria, a total of 342 panoramic radiographs were included. The angulation was estimated on Angle Meter software and categorized into three classes as mild, moderate and extreme. The data were recorded on Microsoft Excel spreadsheet 2021, and descriptively analyzed using IBM SPSS software.

RESULTS

Of the 342 subjects, there were 172 males and 170 females (1.012M:1F). Overall mean age was 33.75 ± 13.86 years. 100/342 subjects showed dilaceration in one or more teeth yielding a subject prevalence of 29.24%. There was no statistically significant difference in age and gender between the individuals who showed dilaceration and those without. The tooth prevalence was 1.49% (150/10089). The mandibular third molars were the most commonly affected teeth. Further, 97/150 teeth were mildly dilacerated (64.67%), 34/150 teeth showed moderate dilaceration (22.67%) and extreme dilaceration was noted in 19 teeth (12.66%).

CONCLUSION

Within the limits of the present study, we reported morphometric analysis of dilacerated teeth from South Indian population after examination of permanent 10,089 teeth from 342 panoramic radiographs. Mandibular third molars were the most commonly affected teeth, which led us to speculate that dilaceration is a true developmental anomaly, unrelated to trauma or other external stimuli.

Finite element analysis of anterior maxillary segmental distraction osteogenesis using asymmetric distractors in patients with unilateral cleft lip and palate

Objective

The treatment of asymmetric maxillary hypoplasia and dental crowding secondary to unilateral cleft lip and palate (UCLP) is often challenging. This study introduced an asymmetric tooth-borne distractor in anterior maxillary segmental distraction osteogenesis and used three-dimensional finite element analysis to evaluate its potential for clinical application in cases of asymmetrical maxillary hypoplasia.

Methods

A cone-beam computed tomography scan of a late adolescent with UCLP was used to construct a three-dimensional finite element model of the teeth and maxillary structures. An asymmetric distractor model was used to simulate conventional distraction osteogenesis and asymmetric distraction osteogenesis (ADO) to evaluate the resultant stress distribution and displacement.

Results

Postoperatively, both distraction methods resulted in anterior maxillary segment advancement with a slight upward movement. ADO yielded a greater increase in the dental arch length on the cleft side and induced rotation of the anterior maxillary segment, potentially improving midline deviation. Both methods showed similar stress distributions, with higher stress concentrations on the cleft side.

Conclusions

ADO may offer clinical advantages in correcting asymmetrical maxillary hypoplasia in patients with UCLP by facilitating asymmetrical expansion and rotation of the maxilla. Further research is needed to generalize these findings to other clinical presentations.

Effect of bisphosphonate vs. osteoprotegerin during orthodontic tooth movement: A systematic review and meta-analysis

Objective

Orthodontic appliances are commonly used to achieve anchorage during orthodontic treatments; however, their use can contribute to oral diseases. Studies have shown that bisphosphonates and osteoprotegerin are highly effective in reducing orthodontic tooth movement. To determine the efficacy of bisphosphonates and osteoprotegerin in reducing orthodontic tooth movement.

Methods

A comprehensive search was conducted across five databases-MEDLINE-PubMed, Scopus, Google Scholar, ScienceDirect, and Taylor & Francis-up to August 2, 2023. Clinical trials conducted in healthy animals, where bisphosphonates and osteoprotegerin were administered during tooth movement, were included. The search identified 3,099 articles, which underwent a two-phase screening process, resulting in twelve studies for the systematic review and seven for the meta-analysis. Risk of bias was assessed using the SYRCLE tool, and Egger's regression was used to evaluate publication bias.

Results

The administration of bisphosphonates was more effective than osteoprotegerin in reducing mesiodistal orthodontic movement. However, osteoprotegerin did not significantly reduce orthodontic tooth movement.

Conclusions

The findings align with previous studies, confirming the superior efficacy of bisphosphonates over osteoprotegerin. Further research is required to determine the optimal dosage and mechanism of action for these drugs in clinical practice, considering the specific objectives of orthodontic treatments.

Soft tissue changes associated with Class III orthopaedic treatment in growing patients: a systematic review and meta-analysis

INTRODUCTION

Achieving a harmonious soft tissue profile and enhancing facial appearance are key goals of early treatment for skeletal class III malocclusion.

AIM

To summarize the current evidence regarding the effects of Class III orthodontic treatment on facial soft tissues, and to compare various Class III orthodontic appliances.

METHODS

A comprehensive search was conducted up to July 2024, using seven databases, with no language restrictions. RCTs and controlled non-randomized studies were included in this systematic review. The GRADE framework was applied to evaluate the quality of evidence.

RESULTS

Thirty studies were included in this review, of which sixteen were appropriate for quantitative synthesis. The age range fell between 6.6 and 12.3 years. The FM/RME protocol resulted in a 1.58 mm increase in upper lip protrusion and a 4.73-degree decrease in the nasolabial angle compared to the control group. Chincup treatment led to a 2.13 mm increase in upper lip protrusion and a 2.63 mm decrease in lower lip protrusion compared to the control group. The pooled estimate demonstrated a significant increase of 1.82 mm in upper lip protrusion, a significant retrusion of 3.14 mm in the lower lip, and a backward movement of the chin by 4.8 mm in patients treated with miniplate-anchored orthopaedic facemask (FM/MP) compared to the untreated group. However, no significant difference was found between FM/RME and FM/MP, except for a noticeable decrease in the nasolabial angle in the FM/RME group. The analysis of FM/Alt-RAMEC versus FM/RME did not reveal any difference in soft tissue outcomes, except for the upper lip protrusion. The Alt-RAMEC group showed a more pronounced anterior movement of the upper lip by 0.67 mm compared to the RME group. The quality of evidence supporting these findings ranged from low to moderate.

CONCLUSIONS

There is low to moderate evidence suggesting that early treatment positively influences the soft tissues in Class III patients. However, these conclusions are based on a two-dimensional analysis of cephalometric images, which may not provide complete or accurate information. Therefore, more RCTs using comprehensive 3D analysis are needed to confirm these results.

REGISTRATION

PROSPERO ( CRD42024517924 ).

Expert consensus on the clinical strategies for orthodontic treatment with clear aligners

Clear aligner treatment is a novel technique in current orthodontic practice. Distinct from traditional fixed orthodontic appliances, clear aligners have different material features and biomechanical characteristics and treatment efficiencies, presenting new clinical challenges. Therefore, a comprehensive and systematic description of the key clinical aspects of clear aligner treatment is essential to enhance treatment efficacy and facilitate the advancement and wide adoption of this new technique. This expert consensus discusses case selection and grading of treatment difficulty, principle of clear aligner therapy, clinical procedures and potential complications, which are crucial to the clinical success of clear aligner treatment.

Selection of density standard and X-ray tube settings for computed digital absorptiometry in horses using the k-means clustering algorithm

BACKGROUND

In veterinary medicine, conventional radiography is the first-choice method for most diagnostic imaging applications in both small animal and equine practice. One direction in its development is the integration of bone density evaluation and artificial intelligence-assisted clinical decision-making, which is expected to enhance and streamline veterinarians' daily practices. One such decision-support method is k-means clustering, a machine learning and data mining technique that can be used clinically to classify radiographic signs into healthy or affected clusters. The study aims to investigate whether the k-means clustering algorithm can differentiate cortical and trabecular bone in both healthy and affected horse limbs. Therefore, identifying the optimal computed digital absorptiometry parameters was necessary.

METHODS AND RESULTS

Five metal-made density standards, made of pure aluminum, aluminum alloy (duralumin), cuprum alloy, iron-nickel alloy, and iron-silicon alloy, and ten X-ray tube settings were evaluated for the radiographic imaging of equine distal limbs, including six healthy limbs and six with radiographic signs of osteoarthritis. Density standards were imaged using ten combinations of X-ray tube settings, ranging from 50 to 90 kV and 1.2 to 4.0 mAs. The relative density in Hounsfield units was firstly returned for both bone types and density standards, then compared, and finally used for clustering. In both healthy and osteoarthritis-affected limbs, the relative density of the long pastern bone (the proximal phalanx) differed between bone types, allowing the k-means clustering algorithm to successful differentiate cortical and trabecular bone.

CONCLUSION

Density standard made of duralumin, along with the 60 kV, 4.0 mAs X-ray tube settings, yielded the highest clustering metric values and was therefore considered optimal for further research. We believe that the identified optimal computed digital absorptiometry parameters may be recommended for further researches on the relative quantification of conventional radiographs and for distal limb examination in equine veterinary practice.

Influence of facial pattern on the aesthetic assessment of the inclination of the occlusal plane in the frontal view

OBJECTIVES

The aim of this study was to analyse the aesthetic perception by orthodontists, dentists and laypeople of the different inclinations on the occlusal plane in the frontal view in relation to facial biotype.

MATERIALS AND METHODS

The three groups of assessors evaluated the aesthetics of images with occlusal plane inclinations of 0º, 2º and 4º in a mesofacial, dolichofacial and brachyfacial face. Scores were assigned from 1 to 10 ("1": poor aesthetics and "10": very satisfactory aesthetics). The data were evaluated by the Kruskal-Wallis test (p < 0.05) and the Mann-Whitney test (Bonferroni correction p < 0.016).

RESULTS

In meso- and dolichofacial faces, orthodontists considered 0º occlusal plane inclination to be significantly more aesthetic than 2º (mesofacial p = 0.004, dolichofacial p < 0.001) and 4º (p < 0.001), and 2º inclination more than 4º (p < 0.001). Dentists and laypeople rated 0º and 2º inclinations as significantly more aesthetic than 4º (p < 0.001) with no significant differences between 0º and 2º inclinations. For the brachyfacial face, the three groups rated 0º and 2º occlusal plane inclination as significantly more aesthetic than 4º inclination (p < 0.001), with 0º and 2º inclinations scoring similarly (p > 0.016).

CONCLUSIONS

Orthodontists were more critical than dentists and laypeople when assessing mesofacial and dolichofacial facial types, whereas no differences were observed between the three groups for brachyfacial faces.  CLINICAL RELEVANCE: The facial pattern influences the perception of the occlusal plane. Understanding these differences is crucial for clinicians, as it can enhance diagnostic accuracy and optimize treatment planning, leading to more personalized and effective orthodontic care.

"Effect of oral systemic administration of vitamin D on the rate of maxillary canine retraction: A randomized controlled trial"

Objective

The trial was conducted to determine the effects of systemically delivered Vitamin D (1,25 dihydroxycholecalciferol) on the rate of maxillary canine retraction till the space closure and on the root resorption.

Materials and methods

A two-arm parallel randomized controlled trial was conducted in patients with Angle's Class I bimaxillary protrusion requiring at least upper first premolars extraction and distal movement of canine for malocclusion correction. The enrolled patients were randomized and allocated to the experimental group (Oral Vitamin D = 0.25 μg given) and control group (Placebo given). The canine retraction was initiated using nickel-titanium (NiTi) closed coil springs delivering a force of 100 gm per side and Vitamin D levels were monitored at monthly intervals. The patients' casts were digitally scanned and examined for differences in the rate of canine retraction at initial (T0), 4 weeks (T1), 8 weeks (T2), 12 weeks (T3), 16 weeks (T4) and 20 weeks (T5) intervals were calculated. The volumetric root resorption was done on CBCT of the area of interest at T0 and after completion of retraction. Descriptive statistics and paired t-test were used to determine any differences.

Results

32 patients (18-24 years) were randomized in the experimental group (n = 16) and control group (n = 16) and no dropout was noted till the end of the study. The results showed a statistically significant increase in the rate of canine retraction in the experimental group as compared to the control group at different time intervals. The differences in the mean canine retraction between group 1 and group 2 at T1-T0, T2-T1, T3-T2, T4-T3, and T4-T0 were 0.28 ± 0.12, 0.29 ± 0.10, 0.31 ± 0.08, 0.37 ± 0.06 and 1.18 ± 0.10 mm respectively. The total mean canine retraction for group 1 was achieved at T4 time interval while it was achieved at T5 interval for group 2. The intergroup comparison of maxillary canine roots showed no statistically significant difference in volumetric root resorption.

Conclusion

The active form of vitamin D can be an effective agent to accelerate orthodontic tooth movement (OTM).

Assessment of biofilm formation on ceramic, metal, and plastic brackets in orthodontic materials by new method using renG-expressing Streptococcus mutans

OBJECTIVE

Oral biofilm has a high acid-producing capacity, increases the risk of enamel demineralization around brackets, and has been identified as a problem in orthodontic treatment. Here, we assessed the risk of biofilm formation by Streptococcus mutans, which is associated with the development of white spot lesions (WSL) on tooth surfaces, using multibracket devices.

METHODS

Various types of brackets were used for the biofilm formation assay with S. mutans coated with human saliva, immersed in renG-expressing S. mutans UA159 (strain with the luciferase gene inserted), and incubated overnight at 37 °C under aerobic conditions containing 5% CO2. The biofilm was washed twice with phosphate-buffered saline (PBS), and 200 μL of luciferin dissolved in PBS was added to each well. The mixture was light shielded and allowed to react for 20 min. Luminescence was measured as the amount of biofilm formed by live cells on the bracket surfaces using an optical emission spectrophotometer.

RESULTS

Biofilm formation was greater in plastic brackets than in ceramic and metal brackets in a number-dependent manner. However, biofilm formation was inhibited as the plastic bracket was coated with saliva.

CONCLUSION

For preventive treatments of WSL onset during orthodontic treatment, orthodontists should carefully select and customize brackets based on patient needs, goals, and biomechanical principles. This study developed a new measurement method using renG-expressing S. mutans UA159 to accurately assess active biofilm formation on bracket surfaces.

An Innovative Approach to Accelerate Maxillary Canine Retraction With Low-Amperage Direct Electric Current: A Preliminary Clinical Study

Background and objective Accelerating orthodontic tooth movement is a significant goal for clinicians and patients. This study aimed to investigate the effectiveness of a low-ampere, electrically inducible tooth movement accelerator device. The study focuses on an innovative intraoral removable device designed to expedite the retraction of maxillary canines. Methods This research was conducted in the Orthodontics Department at Damascus University, Syria, between September 2022 and March 2023, and involved seven patients (five females and two males; mean age: 20.85 ± 1.34 years) initially diagnosed with class II, division I malocclusion. The treatment plan included retraction of the upper anterior teeth in two stages following the extraction of the first premolars on each side. Electrical stimulation was applied during the retraction of the maxillary canines using a removable, custom-manufactured device developed by the researchers. Patients were instructed to wear the device for five hours daily. The variables investigated included the rate of canine retraction, safety, and patient acceptance of the device. Results The average rate of canine retraction was consistent, averaging 1.25 ± 0.13 mm/month. No side effects, such as irritation or discomfort, were observed. Patients reported no adverse effects and stated that they would recommend the technique to others. Five out of seven patients found it easy to adapt to the device, while two found it moderately challenging. Conclusions Our findings showed that low-amperage direct current electrical stimulation effectively accelerated orthodontic movement. The maxillary canine retraction was significantly sped up without any adverse effects. Patients responded positively, indicating feasibility and acceptability. This technique could reduce treatment duration, which is pending further validation.

Periodontal, occlusal, and aesthetic outcomes of missing maxillary lateral incisor replacement: A systematic review and network meta-analysis

INTRODUCTION

The aim of this systematic review was to determine the best treatment alternatives for patients with maxillary lateral incisor agenesis (MLIA) by comparing orthodontic space closure, implant and tooth supported dental prostheses by assessing studies that evaluated their periodontal, occlusal (function) and aesthetic results.

METHODS

The present systematic review was reported according to the indications of the preferred reporting items for systematic reviews and meta-analysis (PRISMA) incorporating network meta-analysis, and the protocol was registered with PROSPERO (CRD42023487245). The PRISMA systematic search, without restriction on language or initial date, was carried out using electronic databases: MEDLINE (PubMed), Scopus and central register of controlled trials. To assess the aesthetic effects of the different treatment methods, an arm-based network meta-analysis was carried out.

RESULTS

The systematic search initially produced 1177 studies. At the end 10 studies met the inclusion criteria. These studies used various methods of treatment for maxillary lateral incisor agenesis including orthodontic space closure, implant-supported and tooth-supported dental prostheses. Data were extracted from the articles selected, and a network meta-analysis was carried out.

CONCLUSIONS

Within the limits of this network meta-analysis, no significant difference was found regarding the aesthetic results between orthodontic space closure or dental implant. Tooth-supported dental prostheses for MLIA reported worse scores in the periodontal indexes than orthodontic space closure treatment but the impact of orthodontic and prosthetic treatment on periodontal health remained contentious. Furthermore, no signs of TMJ dysfunction were observed in patients treated with either orthodontic space closure or prosthetic replacement.

Comparison of two CBCT analysis techniques with conventional periapical radiographs in assessment of tertiary dentin after indirect pulp capping in young permanent teeth

BACKGROUND AND AIM

To compare two cone beam computed tomography (CBCT) analysis techniques for measuring tertiary dentin (TD) volume, density, and root length increase, after indirect pulp therapy (IPT) in young permanent teeth with conventional periapical radiographs.

DESIGN

Comparative study design: Sixty-nine CBCT scans were taken initially (T1) and after 1 year (T2) of IPT. New CBCT analysis technique A, standardization, segmentation, and registration of T1 and T2 scans were performed using ITK-SNAP and 3D Slicer CMF to measure TD volume (mm3), density (gray-level intensity), and root length increase (mm). In the traditional CBCT analysis technique B, analyses were conducted using the In-Vivo software to calculate TD thickness (mm), radiodensity (HU%), and root length increase (mm). Paired t-test and the intraclass correlation coefficient were calculated to compare and assess the reliability of all techniques.

RESULTS

No significant difference between the two techniques existed in the measurement of TD mineral density (Mean [SD]:A = 22.4 [15.4]; B = 24.4 [15.4]; p = .47). Technique A resulted in significantly higher root length increase values (Mean [SD]: A = 1.3 [0.6]; B = 1.1 [0.5]; p = .03). The two techniques showed acceptable reliability levels (0.76-0.99).

CONCLUSION

CBCT analysis techniques yielded similar findings for mineral density. The new CBCT volumetric analysis technique, although more laborious, produced higher values for root length increase, and allowed for measurement of dentin volume.

Unveiling the role of artificial intelligence applied to clear aligner therapy: A scoping review

OBJECTIVES

To conduct a scoping review on the application of artificial intelligence (AI) in clear aligner therapy and to assess the extent of AI integration and automation in orthodontic software currently available to orthodontists.

DATA AND SOURCES

A systematic electronic literature search was performed in the following databases: PubMed, Embase, Web of Science, Cochrane Library, and Scopus. Also, grey literature resources up to March 2024 were reviewed. English-language studies on potential AI applications for clear aligner therapy were included based on an independent evaluation by two reviewers. An assessment of the automation steps in orthodontic software available on the market up to March 2024 was also conducted.

STUDY SELECTION AND RESULTS

Out of 708 studies, 41 were included. Sixteen articles focused on tooth segmentation, four on registration of digital models, 13 on digital setup, and eight on remote monitoring. Moreover, 13 aligner software programs were identified and assessed for their level of automation. Only one software demonstrated complete automation of the steps involved in the orthodontic digital workflow.

CONCLUSIONS

None of the 13 identified aligner software programs were evaluated in the 41 included studies. However, AI-based tooth segmentation achieved 98 % accuracy, while AI effectively merged CBCT and IOS data, supported digital measurements, predicted treatment outcomes, and showed potential for remote monitoring.

CLINICAL SIGNIFICANCE

AI applications in clear aligner therapy are on the rise. This scoping review enables orthodontists to identify AI-based solutions in orthodontic planning and understand its implications, which can potentially enhance treatment efficiency, accuracy, and predictability.

Validation of a New Questionnaire for Assessing the Psychosocial Impact of Gingival Aesthetics (PIGAQ)

AIM

While the importance of gingival aesthetics is increasingly recognized, a questionnaire quantifying its psychosocial impact is still lacking. We have adapted the validated Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) for the gingival context. This study's aim was to develop a new Psychosocial Impact of Gingival Aesthetics Questionnaire (PIGAQ) and test its validity for the general population in Spain, exploring the underlying dimensions of the construct assessed.

MATERIALS AND METHODS

The PIDAQ was adapted to address gingival aesthetics. PIGAQ (23 items) was completed by 200 patients aged from 18 to 85 years, and socio-demographic variables were recorded. The four-dimensional structure of the PIDAQ was respected, adapting the subscales to focus on the gingiva. Descriptive analysis, assessments of reliability and validity and an exploratory factor analysis were performed.

RESULTS

The revised PIGAQ (now containing 20 items) has a Cronbach's alpha coefficient of 0.88 with four underlying factors explaining 61.5% of the total variance. Three items (SI-1, PI-2 and PI-5) were eliminated because of unacceptable fit indices. The Cronbach's alpha coefficients for the subscales are as follows: Gingival Self-Confidence, 0.85; Social Impact, 0.84; Psychological Impact, 0.79; and Aesthetic Concern, 0.76.

CONCLUSION

PIGAQ is a reliable and potentially valid instrument for assessing psychosocial perceptions of gingival aesthetics. The scale was shown to have a satisfactory factor structure and level of internal consistency.

Stress Distribution and Tooth Displacement Analysis of Maxillary Molar Distalization by Different Designs of Jig in a Finite Element Study

Statement of the Problem

Despite the prevalence of CLII malocclusion, still the best mechanotherapy for non-extraction treatment is not verified.

Purpose

The aim of the present study was to evaluate the stress distribution and tooth displacement during maxillary molar distalization with the aid of two different constructions of jigs in three different lever arm heights.

Materials and Method

In this finite element study, models were meticulously constructed to represent the maxillary arch teeth (excluding the third molar), periodontal ligament, alveolar bone, maxillary brackets, main archwire, molar bands, jigs, and mini screws. These models were imported into Ansys software for simulation and analysis. Two different jig configurations with three different lever arm height were created. A 150-gram force was applied to simulate tooth movement, facilitate observation, and analyze its effects on oral components.

Results

In various experimental configurations involving tow jigs with differing lever arm heights, the central incisor exhibited displacement characterized by lingual and distal crown tipping, along with evidence of intrusion. Concurrently, the first molar displayed lingual and distal tipping, as well as extrusion, across six distinct modalities.

Conclusion

In the main, posterior teeth showed distal and lingual tipping and extrusion and anterior teeth demonstrated intrusion mesial and lingual tipping in all models. It seems the differences were due to different lever arm heights. Two types of jig had no significant effect on stress distribution and tooth movement.

Accuracy of deep learning-based upper airway segmentation

INTRODUCTION

In orthodontic treatments, accurately assessing the upper airway volume and morphology is essential for proper diagnosis and planning. Cone beam computed tomography (CBCT) is used for assessing upper airway volume through manual, semi-automatic, and automatic airway segmentation methods. This study evaluates upper airway segmentation accuracy by comparing the results of an automatic model and a semi-automatic method against the gold standard manual method.

MATERIALS AND METHODS

An automatic segmentation model was trained using the MONAI Label framework to segment the upper airway from CBCT images. An open-source program, ITK-SNAP, was used for semi-automatic segmentation. The accuracy of both methods was evaluated against manual segmentations. Evaluation metrics included Dice Similarity Coefficient (DSC), Precision, Recall, 95% Hausdorff Distance (HD), and volumetric differences.

RESULTS

The automatic segmentation group averaged a DSC score of 0.915±0.041, while the semi-automatic group scored 0.940±0.021, indicating clinically acceptable accuracy for both methods. Analysis of the 95% HD revealed that semi-automatic segmentation (0.997±0.585) was more accurate and closer to manual segmentation than automatic segmentation (1.447±0.674). Volumetric comparisons revealed no statistically significant differences between automatic and manual segmentation for total, oropharyngeal, and velopharyngeal airway volumes. Similarly, no significant differences were noted between the semi-automatic and manual methods across these regions.

CONCLUSION

It has been observed that both automatic and semi-automatic methods, which utilise open-source software, align effectively with manual segmentation. Implementing these methods can aid in decision-making by allowing faster and easier upper airway segmentation with comparable accuracy in orthodontic practice.

Engineering soft-hard tissue interfaces in dental and craniofacial system by spatially controlled bioactivities

The interface between soft and hard tissues is constituted by a gradient change of cell types and matrix compositions that are optimally designed for proper load transmission and injury protection. In the musculoskeletal system, the soft-hard tissue interfaces at tendon-bone, ligament-bone, and meniscus-bone have been extensively researched as regenerative targets. Similarly, extensive research efforts have been made to guide the regeneration of multi-tissue complexes in periodontium. However, the other soft-hard tissue interfaces in the dental and craniofacial system have been somewhat neglected. This review discusses the clinical significance of developing regenerative strategies for soft-hard tissue interfaces in the dental and craniofacial system. It also discusses the research progress in the field focused on bioengineering approaches using 3D scaffolds equipped with spatially controlled bioactivities. The remaining challenges, future perspectives, and considerations for the clinical translation of bioactive scaffolds are also discussed.

Possible role of superoxide dismutase 3 in hypoxia-induced developmental defects in murine molars

OBJECTIVES

To investigate the effects of hypoxia on tooth germ development in mice and explore the underlying mechanisms.

METHODS

Tooth germs were extracted from E14.5 mouse embryos and divided into the control and hypoxia groups for organ culture. The hypoxia group was exposed to hypoxia (0% oxygen) for 3 h, followed by normoxia for 21 h. After 2 or 7 days, samples were collected for morphometric analysis, reverse transcription-quantitative polymerase chain reaction, immunohistochemistry (IHC), and immunofluorescent staining (IF). Additionally, superoxide dismutase 3 (SOD3) expression patterns in mandibular molar tooth germs from C57BL/6 mouse embryos were analyzed using IHC. The SOD inhibitor sodium N, N-diethyldithiocarbamate trihydrate (DETC; 400 μM) was applied under normoxia for 3 days, followed by morphometry, IHC, and IF.

RESULTS

After 7 days, the hypoxia group exhibited significantly smaller tooth size, fewer cusps, reduced cell proliferation, and increased apoptosis in the epithelium compared to the control group. Sod3 mRNA expression was higher than other Sod family member expressions in the control group. In the hypoxia group, Sod3 mRNA and SOD3 protein expression were significantly decreased, whereas hypoxia-inducible factor-1 expression and reactive oxygen species levels were increased. SOD3 was primarily expressed in the dental epithelium from E12.5 to E17.5. DETC impaired tooth germ development in the control group, resulting in a phenotype similar to that of the hypoxia group, and significantly reduced amelogenin and msh homeobox 2 expression in the epithelium.

CONCLUSIONS

Hypoxia impairs tooth germ development. SOD3 probably plays a protective role during this process.

Esthetic perception of mandibular anterior teeth during speech and dynamic smile

INTRODUCTION

This study evaluated the esthetic perception of the mandibular anterior teeth during speech by comparing the assessments of laypeople (LP) and orthodontists (ODs).

METHODS

A Class I occlusion model was filmed pronouncing "Czechoslovakia" and smiling. Dynamic smile and speech images were extracted and digitally manipulated to create various dental conditions: ideal alignment, mandibular canine extrusion, mandibular incisor crowding, inclined mandibular occlusal plane, mandibular incisor diastema, and mandibular incisor extraction simulation. Forty-eight participants from each group (LP and ODs) evaluated images using visual analog scales. Statistical analysis employed repeated measures analysis of variance with a 5% significance level.

RESULTS

No significant differences appeared between evaluator group means except for the dynamic smile image. Dynamic smile images received the highest scores, followed by aligned and leveled teeth, both showing significant differences (P <0.05) from each other and the remaining images. Inclined occlusal plane and diastema images received the lowest scores. Group evaluations showed distinct patterns: ODs did not significantly differentiate between canine extrusion, crowding, inclined occlusal plane, and diastema images, whereas LP showed no significant differentiation between incisor extraction, canine extrusion, crowding, and diastema images.

CONCLUSIONS

Speech images received lower attractiveness ratings than ideal occlusion in both groups. No significant differences appeared between LP and OD evaluations except for the dynamic smile image assessment.

The normal width of the lateral incisors in the maxilla in an European population

OBJECTIVES

Dental anomalies are clinical alterations that originate during the tooth formation process. This prospective study aims to establish the norm and hypoplasia values for maxillary lateral incisors. Additionally, it aims to describe the relationship between the width of the lateral and the central incisors, considering gender, age, and body height.

MATERIALS AND METHODS

The first 103 consecutive patients meeting the inclusion criteria were included in the study. The upper jaw of each patient was scanned, and the scans were saved as standard tessellation language (STL) files. The upper incisors of each digital cast were measured on the computer. Two examiners performed the same measurements independently.

RESULTS

The average size of the maxillary central incisor was 8.59 ± 0.51 mm, while the average size of the maxillary lateral incisor was 6.64 ± 0.46 mm. A formula describing a relationship between the central (x) and lateral (y) incisors was defined with a linear regression analysis y = 1.88 + 0.55 * x. Width of maxillary incisors [11, 12, 21, 22] increased with height (p = 0.028, p = 0.016, p = 0.016, p = 0.046 respectively).

CONCLUSIONS

Hypoplasia of the maxillary lateral incisor can be defined for teeth with a mesiodistal width less than 6.18 mm in a patient that is represented with the test group. A relationship between the maxillary lateral incisors and central incisors could have been established by means of a formula.

CLINICAL RELEVANCE

The width of the maxillary lateral incisors allows a precise orthodontic and prosthetic planning.

Comparative Evaluation of Shear Bond Strength of Aesthetic Orthodontic Brackets Bonded to Aged Composite Restorative Resin Materials

Patient demands for aesthetic orthodontic brackets (OBs) has increased since orthodontic treatments are of long duration. Clinicians encounter old composite restorations frequently, against which OBs need to be bonded. This study aims to determine the shear bond strength (SBS) of two aesthetic OBs (ceramic and resin) against aged composite resins (flowable and packable) after standard surface treatment. A total of 96 disk-shaped specimens of two aged (A) composite resins [flowable (F) and packable (P)] were divided into eight groups, using ceramic (C) and plastic (P) brackets, out of which four subgroups served as the control [non-aged (N)FC, NPC, NFR, NPR] and four as experimental [AFC, APC, AFR, APR]. Surface treatment included mechanical [air abrasion] and chemical [Assure Plus and Transbond XT]. After 24 h of storage, the specimens were tested for SBS and observed for failure mode using adhesive remnant index scores. Mean values of SBS in each subgroup were analyzed statistically using a one-way analysis of variance test and Tukey post hoc test. All probability 'p' differences were significant at a value of 0.05 and less. All aged composite resin subgroups had decreased bond strength than controls, with all subgroups bonded with plastic brackets having the least bond strengths that were clinically nonacceptable [≤7 to 10 MPa]. Flowable composites when bonded with either ceramic or plastic brackets had higher strength than packable composites. Ceramic brackets had higher SBS than plastic brackets for both flowable and packable composites. Significant differences in bond strength were observed among subgroups of plastic brackets. Ceramic brackets were associated with a higher residue of adhesives on the composite surface. Aged composite resins exhibit significantly lower SBS than fresh composites, with ceramic brackets and flowable composites producing better bond strength values than plastic brackets and packable composites.

Artificial Intelligence-Supported and App-Aided Cephalometric Analysis: Which One Can We Trust?

Background: This study aimed to compare the reproducibility and reliability of the AI-supported WebCeph and app-aided OneCeph cephalometric analysis programs with a manual analysis method and to evaluate the analysis times. Methods: The study material consisted of pretreatment lateral cephalograms from 110 cases. Cephalometric analyses were performed manually, using the WebCeph program, and using the OneCeph application. A total of 11 skeletal, 6 dental, and 3 soft tissue parameters were measured. Cephalometric analyses of 30 randomly selected cases were performed again using three methods. The analysis times were recorded. Results: The WebCeph program and OneCeph application are highly compatible with the manual analysis method in terms of all parameters, except for SN measurement. It was found that the WebCeph program and the OneCeph application demonstrated moderate agreement in U1-NA distance measurement, while statistically high agreement was observed among all three methods for other dental parameters. It was determined that there was a moderate agreement among the methods in terms of nasolabial angle, whereas a statistically high level of agreement was found for the other soft tissue parameters. The analysis time was found to be the lowest in the WebCeph program and the highest in the manual analysis method. Conclusions: The WebCeph program and OneCeph application showed a high degree of compatibility with the manual analysis method, except for SN, SNA, Gonial angle, Articular angle, U1-NA distance and nasolabial angle measurements. Due to the higher correlation between OneCeph and the manual method, it can be concluded that the OneCeph application is the best alternative to the manual method.

Influence of orthodontic archwire (nickel-titanium versus copper-nickel-titanium) on pain in adult patients in the aligning phase of treatment with self-ligating brackets (two months of follow-up): a prospective observational pilot study

BACKGROUND

The aim of this pilot study was to analyze the influence of a nickel-titanium archwire (NiTi) and a copper-nickel-titanium archwire (Cu-NiTi) on pain levels in adult patients during the first two months of orthodontic treatment with self-ligating brackets.

METHODS

This prospective observational pilot study was carried out at the Dental Clinic of the University of Salamanca between 2023 and 2024. This study analyzed 30 adult orthodontic patients who began treatment with self-ligating brackets. The participants were distributed into two study groups (n = 15) for treatment with initial NiTi and Cu-NiTi archwires. At the beginning, a 0.014-inch archwire was used, and a 0.016-inch archwire was used after a month. The level of pain was measured using a visual analog scale (VAS) at the beginning of treatment (T0), at one month (T1), and at two months (T2). At each time point (T0, T1, and T2), pain was measured at baseline and at 4, 24, and 48 h after archwire placement or replacement. The data were analyzed using Spearman's correlation coefficient and the Mann-Whitney test (p < 0.05).

RESULTS

The mean age of the participants (n = 30) was 31.34 (± 6.05) years. The maximum pain peak was in the first 48 h after placing the initial archwire (5.57 ± 1.72). The age and sex of the participants did not influence the pain levels in the sample studied. The composition of the orthodontic archwire only influenced the pain levels at the beginning of treatment (T0) (p < 0.05); in this case, the NiTi group (1.73 ± 1.53) described a higher level of pain than that of the Cu-NiTi group (1.07 ± 1.36); in the rest of the follow-up period, no significant differences were observed.

CONCLUSIONS

Within the limitations of this study, we observed that the orthodontic archwire material (nickel-titanium versus copper-nickel-titanium) only influenced pain levels at the beginning of orthodontic treatment.

Increasing Participation and Completion Rates in Questionnaire Surveys of Primary Care Patients: Cluster-Randomized Study

BACKGROUND

Participation and completion rates in questionnaire-based surveys are often low.

OBJECTIVE

This study aims to assess participation and completion rates for a survey using paper and mixed mode questionnaires with patients recruited by research assistants in primary care waiting rooms.

METHODS

This cluster-randomized study, conducted in 2023 in France, involved 974 patients from 39 practices randomized into 4 groups: "paper with incentive" (n=251), "paper without incentive" (n=368), "mixed mode with tablet" (n=187), and "mixed mode with QR code" (n=168). Analyses compared the combined paper group with the 2 mixed mode groups and the "paper with incentive" and "paper without incentive" groups. Logistic regressions were used to analyze participation and completion rates.

RESULTS

Of the 974 patients recruited, 822 (women: 536/821, 65.3%; median age 52, IQR 37-68 years) agreed to participate (participation rate=84.4%), with no significant differences between groups. Overall, 806 patients (98.1%) answered all 48 questions. Completion rates were highest in the combined paper group (99.8%) compared to mixed mode groups (96.8% for paper or tablet, 93.3% for paper or QR code; P<.001). There was no significant difference in completion rates between the "paper with incentive" and "paper without incentive" groups (100% vs 99.7%).

CONCLUSIONS

Recruiting patients in waiting rooms with research assistants resulted in high participation and completion rates across all groups. Mixed mode options did not enhance participation or completion rates but may offer logistical advantages. Future research should explore incentives and mixed-mode strategies in diverse settings.

Three-dimensional comparative analysis of upper central incisors external apical root resorption/ incisive canal changes in first premolar extraction cases: clear aligners Versus passive self-ligating fixed braces

OBJECTIVE

To assess the upper central incisor's (U1) external apical root resorption (EARR) and incisive canal (IC) changes and their influencing factors under clear aligners and passive self-ligating fixed braces in first premolar extraction cases using CBCT.

MATERIALS AND METHODS

This retrospective study included 60 participants (120 teeth) with similar baseline characteristics based on the American Board of Orthodontics discrepancy index scores. Participants were divided into clear aligner (CA) and passive self-ligating fixed appliance (FA) groups, with 30 participants per group. Pre- and post-treatment EARR, IC dimensional changes, U1-IC proximity, and orthodontic movements were analyzed through CBCT using Invivo 6.0.3 software. Descriptive and analytical statistics are performed, and a P-value < 0.05 is considered statistically significant.

RESULTS

The CA group exhibited statistically significantly lower U1-EARR compared to FA group. However, there were no significant differences in overall IC dimensions (P < 0.05). In FA, contact or invasion of U1 with IC are associated with a significant increase in EARR, but not in CA. The invasion also reveals significant reductions in IC dimensions in FA, whereas CA exhibited more limited changes (P < 0.05). Retraction and intrusion were significantly positively correlated with U1-EARR in FA, whereas intrusion only was correlated positively with U1-EARR in CA (P < 0.05). In both FA and CA, there was no significant correlation between the torque and U1 EARR (P > 0.05). Retraction, intrusion, and torque movements had differential impacts on IC dimensions in FA and CA treatments.

CONCLUSION

In this study, our findings indicate that in cases involving the extraction of first premolars, Invisalign® clear aligners may have less U1-EARR than passive self-ligating fixed braces but no significant differences in the overall IC dimensions between both appliances. Clear aligners may reveal better outcomes in U1 EARR/IC changes concerning U1-IC proximity and different orthodontic movements. These findings may be necessary for orthodontists to consider during treatment planning.

CLINICAL RELEVANCE

Clear aligners may be an appropriate choice in first premolar extraction cases, especially when the U1 is closer to IC or when there is a need for more retraction, intrusion, and torque. Their potential to reduce root resorption while preserving IC dimensions may make them more advantageous over passive self-ligating fixed braces in these scenarios.

Evaluation of NaOCl application prior to resin infiltrant or fluoride-containing resin varnish in the treatment of white spot lesions: An in vitro study

OBJECTIVE

The aim of this in vitro study is to investigate the effect of NaOCl (5.25 %) prior to resin infiltration and resin varnish on microhardness, surface roughness, and DIAGNOdent Pen values in the treatment of white spot lesions (WSLs).

METHODS

The artificial initial caries lesions were created in 160 human enamel samples. The demineralizated samples were divided into five groups: resin infiltration (ICON; DMG, Hamburg, Germany), NaOCl + ICON, resin varnish (Clinpro XT; 3M ESPE, Seefeld, Germany), NaOCl + Clinpro XT, and a negative control group. Enamel samples that underwent thermocycling aging were subjected to 5.000 cycles between 5-55 °C (N = 32, n = 16 for aging subgroups). Surface roughness (Ra), Vicker's microhardness (VHN), and DIAGNOdent Pen (Kavo, Biberach, Germany) (DDP) values were recorded at the baseline, after demineralization, after treatment, and after the thermal aging stages. The micro-CT analysis, microleakage, and Scanning Electron Microscope images were evaluated after treatment procedures and thermal aging. Robust ANOVA, Pearson's chi-square, and McNemar tests were used for statistical analysis. The significance level was p < 0.05.

RESULTS

The main effect of both group and stage was statistically significant for DDP, Ra, VHN, and micro-CT values. All treatment procedures improved the demineralized enamel compared to the negative control group (p < 0.001). The application of NaOCl (5.25 %) before resin infiltration increased microhardness but also in roughness. The resin-infiltrated groups showed less microleakage than the resin-varnish-treated groups (p < 0.001).

CONCLUSION

The application of NaOCl prior to resin infiltration or resin varnish did not result in any important alterations in the examined parameter values.

Current situation, trends, and challenges navigating temporary anchorage devices usage among orthodontists in China: a comprehensive multi-center survey

BACKGROUND

The temporary anchorage devices (TADs) are presently a viable and popular treatment option for orthodontics all over the world. However, there is a lack of investigation and research on its application among orthodontists in China. This study aims to explore factors influencing temporary anchorage devices usage and compare current perspectives and usage patterns between orthodontic specialists and general dentists, thereby establishing new consensus and guiding future improvements.

METHODS

A cross-sectional study using a multi-center structured questionnaire was designed. The Chi-square test, Mann-Whitney U test, and logistic regression were performed.

RESULTS

Respondents were from 30 provincial-level regions. Most doctors had relatively rich clinical experience in orthodontics, with 65.70% working for over 10 years. Respondents reported a relatively high usage rate (87.54%) and satisfaction with TADs (93.85%). The analysis result showed Chinese orthodontists who received more TADs training (P < 0.01), had higher educational attainment (P < 0.01), and used more clear aligners (P < 0.01) tended to use TADs more frequently. About 95.90% of respondents believed TADs helped achieve higher treatment goals, 68.23% agreed they could shorten treatment duration, and 51.82% believed they reduced the probability of orthodontic-orthognathic treatment. Differences in the understanding of indications for TADs, improvement method of TADs can be observed between orthodontic specialists and general dentists (P < 0.05).

CONCLUSIONS

Chinese orthodontists were relatively active in using TADs. The factors most closely associated with TAD usage included related training, the type of orthodontic appliances used and the highest educational attainment. Orthodontic specialists and general dentists might had differing perspectives regarding TADs, but they tended to follow similar management procedures.

Functional modification and antibacterial evaluation of orthodontic adhesives with poly (lysine)-derived carbon dots

Fixed appliances used in orthodontic treatment make oral hygiene difficult to maintain, leading to bacterial adhesion around brackets and consequently resulting in white spot lesions (WSLs). After the bracket debonding, the residual adhesive is difficult to remove precisely due to its appearance similar to tooth enamel. In this study, we successfully synthesized small-sized and highly active PL-CDs by one-pot pyrolysis using ε-poly-l-lysine as a precursor. It was incorporated into orthodontic adhesives for multi-function modification. Based on our experimental results, the 3 wt% PL-CDs modified orthodontic adhesive exhibited excellent antibacterial properties and color identifiability. The addition of 3 wt% PL-CDs did not affect the biocompatibility and mechanical properties of the adhesive, and the cell survival rate was up to 80%. Therefore, this study provides a new strategy to solve the two major problems of enamel white spot and adhesive removal in the process of fixed orthodontics, and has important clinical application.

Three-dimensional analysis of mandibular and condylar growth using artificial intelligence tools: a comparison of twin-block and Frankel II Appliances

BACKGROUND

Analyzing the morphological growth changes upon mandibular advancement between Twin Block (TB) and Functional Regulator II (FR2) in Class II patients involves measuring the condylar and mandibular changes in terms of linear and volumetric measurements, as well as the distances registered after superimposition. Correspondingly, 3D digital assessment with the benefit of artificial intelligence tools was applied, and color-coded distance maps were descriptively interpreted to visualize the direction of growth.

SUBJECTS AND METHODS

Twenty patients aged 9 to 12 years with skeletal Class II malocclusion with overjet (5-9 mm) were enrolled into two groups: Group 1 (TB) and Group 2 (FR2). CBCT radiographs were taken at T0 (prior to treatment) and T1 (at the end of effective treatment; 7-11 months). 3D UX-Net algorithm was used to extract the 3D models and obtain the volumes. Visual Basic software was employed to develop a method for calculating the 3D distances and angles. 3D superimposition methods through Viewbox software were utilized to analyze growth direction following the treatments, using color-coded distance map visualizations.

RESULTS

The average volume increase of the mandible, right and left condyle was 2666.00 ± 1469.16 mm³, 207.70 ± 125.28 mm³, and 216.90 ± 121.65 mm³, respectively, after TB treatment, and 3316.10 ± 1552.29 mm³, 208.90 ± 116.85 mm³, and 193.65 ± 114.25 mm³, respectively, after FR2 treatment. The mean absolute distances (MAD) for the mandible, right, and left condyle from T1 to T0 were in TB group 1.238 ± 0.757 mm, 2.248 ± 0.346 mm, 2.267 ± 0.593 mm, respectively, and in FR2 group 1.417 ± 0.550 mm, 2.616 ± 1.063 mm, 2.475 ± 0.916 mm, respectively. The visualization of color-coded maps revealed a superior-posterior growth direction of the condyle measuring within 3 mm after the treatment.

CONCLUSIONS

Although mandibular and condylar volumes increased in each group when comparing T0 to T1, indicating the efficacy of both appliances in enhancing growth, no clinically or statistically significant differences were observed between the groups in terms of volumetric, linear, and 3D superimposition changes. However, color-coded distance maps demonstrated a consistent pattern of posterior-superior relocation of the condyles in most cases after treatment when comparing T1 to T0, whereas the back of the ramus in more than half of the cases has moved backwards. With no statistical differences between the studied groups.

Current trends and research advances on the application of TiO2 nanoparticles in dentistry: How far are we from clinical translation?

The great potential of nanotechnology-based knowledge during the past decade has shown great potential to elevate human living standards and enhance healthcare conditions through diagnosing, preventing, and treating different diseases. Among abundant nanoparticles (NPs), inorganic NPs feature distinctive biological and physicochemical properties compared to their conventional counterparts which do not endow. TiO2 NPs possess excellent properties including low-cast, antibacterial properties, biocompatibility, and physicochemical stability. The present review highlights and discusses the current trends in applying TiO2 NPs in dentistry ranging from TiO2-based nanocomposite in endodontics, orthodontics, and biofilm prevention. Moreover, the potential of TiO2 NPs in developing new photodynamic therapy and the next generation of oral care products is outlined. In the end, the clinical translation of TiO2-based dental materials is brought to the forefront which is impetus and of great importance to developing inorganic NP-based dental materials.

Changes in the Upper Airway Dimension Following the Use of Functional Appliances in Children with Obstructive Sleep Apnea: A Systematic Review

Introduction: Obstructive Sleep Apnea Syndrome (OSAS) is a sleep-related breathing disorder common in children, often linked to craniofacial anomalies like retrognathic mandibles in Class II malocclusions. Functional appliances (FAs) have been proposed as non-invasive treatments to improve OSAS symptoms by modifying upper airway dimensions. Objective: this systematic review evaluates the effectiveness of functional appliances in improving upper airway structures in children with OSAS. Materials and Methods: the study was conducted according to PRISMA guidelines, analyzing studies published between 2004 and 2024 on PubMed, Scopus, Web of Science, Embase, and Cochrane Library databases. Inclusion criteria focused on growing patients (≤14 years) with OSAS and Class II skeletal malocclusions treated with FAs. Results: Of 1298 articles screened, four studies met the inclusion criteria. All studies reported a significant increase in upper airway dimensions of approximately 21% after treatment with FAs. Specifically, the cephalometric and tomographic evaluations revealed a clear enlargement of the superior posterior airway space of about 0.5 mm and a consequent improvement of the respiratory function. Discrepancies arose regarding changes in soft palate length and hyoid bone position, perhaps due to the measurement methods' variation. Conclusions: Functional appliances appear effective in improving upper airway dimensions and alleviating OSAS symptoms in children. However, the limited number of studies, small sample sizes, and short follow-up periods emphasize the need for further research to confirm long-term efficacy and standardize evaluation protocols.

Accuracy Evaluation of Indirect Bonding Techniques for Clear Aligner Attachments Using 3D-Printed Models: An In Silico and Physical Model-Based Study

An inaccurate bonding procedure of the attachments related to clear aligner systems could influence the predictability of tooth movement The aim of this study was to compare the positioning reliability of horizontal and vertical orthodontic clear aligner attachments.

MATERIALS AND METHODS

A total of 70 horizontal and 70 vertical orthodontic clear aligner attachments were bonded to five upper and five lower experimental anatomically based acrylic resin models with 14 clinical crowns each. The experimental anatomically based acrylic resin models were randomly distributed to the following study groups: Group A-horizontal orthodontic clear aligner attachments (n = 70) (HORIZONTAL) and Group B-vertical orthodontic clear aligner attachments (n = 70) (VERTICAL). Afterward, the orthodontic clear aligner attachments were digitally planned using orthodontic planning software, and orthodontic templates were manufactured by thermoforming on 3D-printed models in trilayer glycol-modified polyethylene terephthalate. Both horizontal and vertical orthodontic clear aligner attachments were put through an intra-oral scan to obtain a postoperative digital image, and PAPver, PCPver, PMVver, AUver, Alver, PPMhor, PPDhor, PMVhor, AMhor and ADhor cephalometric parameters were analyzed using a t-test or a non-parametric Mann-Whitney-Wilcoxon test.

RESULTS

The results showed that all cephalometric parameters showed statistically significant differences (p < 0.05) between the accuracy of the indirect bonding technique for horizontal and vertical orthodontic clear aligner attachments, except for the PAPver (p = 0.6079) and PMVhor (p = 0.5001) cephalometric parameters.

CONCLUSIONS

The vertical orthodontic clear aligner attachments are more accurate than the horizontal orthodontic clear aligner attachments through the indirect bonding technique.

Relationships between periodontal biotype and anatomical bone features of placement sites for orthodontic anchoring screw: a cross-sectional study

OBJECTIVES

This study investigated relationships between bone thickness at the insertion sites of orthodontic anchoring screws (OASs) and periodontal biotype (PB) using cephalograms and cone-beam computer tomography (CBCT).

MATERIALS AND METHODS

The PB at the maxillary central incisors was evaluated to differentiate into three categories. In total, 71 patients were examined to determine the relationship between PB and palatal bone thickness using cephalograms. Of these, 57 patients with CBCT were investigated further to explore the relationship between PB and bone thickness at the palatal and buccal regions. Mann-Whitney U-test and t-test were performed for comparisons in each PB group.

RESULTS

The thickness of the palatal bone (p = 0.010) and cortex (p = 0.006) in patients with thick biotype in posteroanterior (PA) cephalograms was significantly greater than that those with thin biotype. CBCT evaluations showed that the paramedian bone thickness in the section between premolars in thick biotype (8.38 ± 2.61 mm) was significantly greater than that in thin biotype (6.41 ± 2.95 mm, p = 0.000). Regarding the buccal alveolar area, the cortical bone thickness in thick biotype was greater than those in medium and thin biotypes (p < 0.0167).

CONCLUSIONS

Thick biotype had thicker paramedian bones and palatal cortexes than with thin biotype in PA cephalograms. From CBCT images, the paramedian bone thickness in the section between premolars significantly differed according to PB. Cortical bone thickness in the buccal area from the first premolar to the second molar in the maxilla demonstrated statistically significant differences among PBs.

CLINICAL RELEVANCE

PB is a potentially useful preoperative screening test for OAS placement.

The Effect of the I-Arch on the Buccal Alveolar Crest in Comparison with the Traditional Archwire Sequence: A Randomized Controlled Clinical Trial

Background/Objectives: The nature, diameter, and cross-section of orthodontic archwires affect tooth movement and the surrounding alveolar bone. Researchers have explored different features of archwires to optimize treatment outcomes. In this context, this study aimed to evaluate the properties of the I-arch for its effects on alveolar bone height, dehiscence, fenestration, and treatment duration. Methods: Forty patients (eight males, and thirty-two females; mean age: 20.97 ± 2.41 years) with dental crowding ≤ 6 mm and Class I malocclusion were treated without extractions. They were randomly divided into two groups: the experimental group (EG, n = 20), treated with the I-arch, and the control group (CG, n = 20), treated with traditional archwires of the MBT technique. Two CBCT scans were taken for each patient, one before treatment (T0) and one after leveling (T2). The studied teeth were upper and lower centrals, canines, and second premolars. The treatment duration was measured across three periods: T0-T1, T1-T2, and T0-T2. Results: Alveolar bone resorption, dehiscence, and fenestration were lower in the EG. Total treatment duration (T0-T2) was similar between groups, but the first period (T0-T1) was significantly shorter in the EG (p < 0.05). Conclusions: The I-arch resulted in fewer side effects on alveolar bone height during leveling and alignment.

Balancing the Load: How Optimal Forces Shape the Longevity and Stability of Orthodontic Mini-Implants

Objective: This study aims to investigate the mechanical behavior of titanium (Ti6Al4V) mini-implants (MIs) under varying orthodontic forces using finite element analysis (FEA) and to evaluate their performance and durability under realistic clinical conditions. Optimal orthodontic forces significantly influence the structural integrity and functional longevity of MIs while minimizing adverse effects on surrounding bone tissues. Materials and Methods: A commercially available MI (diameter: 2.0 mm, length: 12 mm) was modeled using FEA. The mandible geometry was obtained using computed tomography (CT) scanning, reconstructed in 3D using SpaceClaim software 2023.1, and discretized into 10-node tetrahedral elements in ANSYS Workbench. Material properties were assigned based on the existing literature, and the implant-bone interaction was simulated using a nonlinear frictional contact model. Orthodontic forces of 2 N and 10 N, inclined at 30°, were applied to simulate clinical loading conditions. Total displacement, von Mises stresses, equivalent strains, fatigue life, and safety factors were analyzed to assess the implant's mechanical performance. Results: At 2 N, the MI demonstrated minimal displacement (0.0328 mm) and sustained approximately 445,000 cycles under safe fatigue loading conditions, with a safety factor of 4.8369. At 10 N, the implant's lifespan was drastically reduced to 1546 cycles, with significantly elevated stress (6.468 × 105 MPa) and strain concentrations, indicating heightened risks of mechanical failure and bone damage. The findings revealed the critical threshold beyond which orthodontic forces compromise implant stability and peri-implant bone health. Conclusions: This study confirms that maintaining orthodontic forces within an optimal range, approximately 2 N, is essential to prolong MI lifespan and preserve bone integrity. Excessive forces, such as 10 N, lead to a rapid decline in durability and increased risks of failure, emphasizing the need for calibrated force application in clinical practice. These insights provide valuable guidance for enhancing MI performance and optimizing orthodontic treatment outcomes.

Biological and mechanical properties of a self-curing acrylic resin enriched with AgNPs as a proposal for orthopedic aparatology

Polymethylmethacrylate (PMMA) is widely used in dentistry, but its inherent characteristics, such as roughness and porosity, can facilitate the formation of bacterial biofilms. However, the integration of silver nanoparticles (AgNPs) can provide antimicrobial properties. Ongoing research endeavors aim to preserve post-nanoaggregation biocompatibility without compromising the mechanical integrity of the material. In this study, we investigated the biological and mechanical attributes of a PMMA nanocomposite infused with AgNPs biosynthesized from Pelargonium × hortorum. A method has been described to incorporate nanoparticles into the polymer at minimum concentrations. In the results, LC-MS-MS revealed the presence of 56 biochemical compounds. UPLCHRESIMS-MS/MS was used to compare the phytochemical profiles of the leaf extract of Pelargonium × hortorum before and after the formation of AgNPs, which were identified with spherical morphology, an absorbance of 28.5 ± 8.16 nm and a particle size of 415 nm. The MIC of AgNPs was 10 μg mL-1. In bacterial MTT, a decrease to 18.2 ± 2.5% with PMMA-10 μg mL-1 was observed (p < 0.05). Decreased cell viability was found only in PMMA-0 μg mL-1 at 89.1 ± 6.7%, indicating no cytotoxicity. These findings suggest a promising bionano material that is suitable for orthodontic and orthopedic devices and warrants further research.

Effects of malocclusion and orthodontic treatment on quality of life among orthodontic patients with craniofacial disorder compared to healthy controls : A cross-sectional study

PURPOSE

Craniofacial disorders (CD) affect the Oral Health Impact Profile (OHIP). Therefore, this study evaluates the OHIP in orthodontic patients with cleft lip and/or palate or Robin sequence compared to healthy controls (C).

METHODS

A prospective, cross-sectional study was conducted. Oral health-related quality of life (OHRQoL) was assessed using the OHIP-14 questionnaire, with responses categorized into functional and psychological well-being items. In addition, the study considered the influence of crossbite, orthodontic appliance type, oral hygiene, and speech therapy. A high OHIP score represents a good quality of life. The Mann-Whitney test was used for nonparametric quantitative variables; statistical significance was set at p < 0.05.

RESULTS

The study included 119 participants (ages 7-21 years; 61 male, 58 female), divided into a CD group consisting of patients with cleft lip and/or palate or Robin sequence (n = 42) and a control group (C; n = 77; mean age 13.5 ± 5.2 and 14.3 ± 3.3 years, respectively). Both groups showed comparable OHIP-14 scores. The CD group reported significantly higher satisfaction regarding nutritional intake (p = 0.03), while the social and psychological dimensions were reduced (p = 0.04). Factors like crossbite, orthodontic appliance and speech therapy did not have a significant impact on OHIP. CD patients with good oral hygiene showed significantly superior self-reported psychological OHIP (p = 0.04).

CONCLUSION

Patients with cleft lip and/or palate or with Robin sequence exhibited OHIP scores comparable to healthy individuals despite their underlying condition. Early guidance on dental care and tooth-friendly nutrition has the potential to improve OHRQoL. Additionally, providing supplemental psychological support during orthodontic treatment is advisable.

Perception thresholds of dental and gingival asymmetries by orthodontists, dentists, and laypeople when observing close-up smile images using eye tracking technology

INTRODUCTION

This study aimed to investigate the perception thresholds of dental and gingival asymmetries in close-up smile images for orthodontists, dentists, and laypeople.

METHODS

Seven sets of close-up smile images were created, in which gingival and dental asymmetries were intentionally incorporated using a software-imaging program. The alterations included unilateral changes to the gingival border and incisal edge of the central and lateral incisors and crown width of the lateral incisor. Combination sets of both dental and gingival asymmetries together were also created. Eye-tracking technology was used to assess visual attention by measuring the fixation duration of the area of the alteration of each image by 195 participants in 3 groups: orthodontists, dentists, and laypeople. Statistical analysis was performed using analysis of variance with Bonferroni adjustment for multiple comparisons, to determine the perception thresholds for each group.

RESULTS

Orthodontists and dentists perceived asymmetry of the gingival border of the central incisor at threshold levels of 1 mm, whereas laypeople perceived this asymmetry at 1.5 mm. Dentists and orthodontists were more sensitive to alterations in the gingival border of the lateral incisor, with a threshold of 1 mm, compared with laypeople, who had a threshold of 2 mm. Wear on the central incisor was perceptible at 1 mm for all groups, whereas wear on the lateral incisor was perceptible at 0.5 mm for orthodontists and dentists and 1 mm for laypeople. The perception threshold values for lateral width discrepancy were 2 mm for orthodontists, 3 mm for dentists, and 4 mm for laypeople.

CONCLUSIONS

On the basis of the perception thresholds found in this study, greater visual attention is drawn toward gingival asymmetries located closer to the midline and dental asymmetries that alter the smile arc.

Comparing the efficacy of heat-activated NiTi (HANT) versus conventional NiTi archwires: A systematic review and meta-analysis

OBJECTIVE

To assess the effectiveness of heat-activated NiTi (HANT) wires compared to NiTi wires during orthodontic alignment, through a systematic review and meta-analysis.

SEARCH METHODS

We comprehensively searched databases up to January 2024, including MEDLINE, Web of Science, EMBASE, Scopus, and Cochrane's CENTRAL, without language or date restrictions.

SELECTION CRITERIA

Clinical studies aligning with the PICO question were included, and their bias risk was evaluated using the Cochrane Risk of Bias 2.0 tool.

DATA COLLECTION AND ANALYSIS

Data were collected using custom forms, and a meta-analysis was performed using random-effects inverse variance. Primary outcome was Little's Irregularity Index (LII) changes. Secondary outcomes were pain intensity and root resorption.

RESULTS

Thirteen clinical studies were reviewed, with nine included in the meta-analysis. No significant differences were observed in LII changes during the first four months, with similar findings in the first, second and third months. In the fourth month, NiTi wires exhibited higher reductions. Pain intensity did not differ between groups on the first or the seventh day. No significant difference in root resorption was found between the two groups.

CONCLUSIONS

HANT and conventional NiTi wires showed comparable effectiveness in reducing LII, pain levels, and root resorption during the orthodontic alignment phase. While HANT wires may entail higher costs, their ease of insertion and ligation offer practical advantages. Ultimately, choosing between wire types should consider individual patient needs and clinician preferences.

Variation of chin morphology and mandibular incisor length in different facial divergence patterns: New insights from CBCT records

AIM

Evaluate constitutional differences in chin morphology and volume, and mandibular tooth size, between different facial divergence patterns.

MATERIALS AND METHODS

The sample consisted of 284 pretreatment cone beam computed tomography (CBCT) images of growing and non-growing patients who were stratified into 4 groups based on mandibular plane inclination to cranial base (SN) angle. Linear and angular measurements were made on the lateral CBCT images: mandibular lateral incisor crown (I-C) total (I-A) lengths, the distances between point D (centre of symphysis) and both incisor apex (D-A) and menton (D-Me) and between cemento-enamel junction and menton (CEJ-Me); chin width at the level of the central incisor apex (CWA) and point D (CWD); and the angles of the anterior and posterior symphyseal slopes. The volume of the symphysis was measured using a specialized 3D imaging software. Group differences and associations between parameters were gauged through the three-way ANOVA analysis.

RESULTS

I-C, I-A, D-A, D-Me and CEJ-Me were greater in the hyperdivergent group (p < .001). CWA and CWD were wider in the hypodivergent group (p = .003). Volume of the chin and inter-slope angles were similar in all groups (p > .05). The anterior slope angle decreased with hyperdivegence (p < .005) in opposite pattern to the posterior slope angle (p < .005).

CONCLUSIONS

Shape differences in mandibular symphysis were observed between opposite divergence patterns. Mandibular incisors were longer with hyperdivergence and shorter with hypodivergence. However, chin volumes were similar across divergence groups. These findings underline the role of genetic and environmental factors that impact facial growth.

Comparison of upper airway volume and hyoid position after camouflage orthodontic or orthodontic-orthognathic treatment in patients with skeletal class Ⅲ malocclusion with normal-angle vertical pattern

OBJECTIVES

This study aims to compare the effects of two orthodontic treatment modalities for skeletal class Ⅲ malocclusion on specific changes in airway volume, morphology, palatal angle, mandibular rotation, and bone displacement. Results provide scientific evidence for the selection of orthodontic treatment plans and reduce the risk of developing obstructive sleep apnea hypopnea syndrome (OSAHS).

METHODS

Thirty-six patients diagnosed with skeletal class Ⅲ malocclusion at the Department of Orthodontics, the Affiliated Stomatological Hospital of Nanjing Medical University from September 2018 to December 2023 were divided into two groups: orthodontic-orthognathic treatment group (18 patients) and camouflage orthodontic treatment group (18 patients). Changes in airway volume, cross-sectional area, palatal angle, mandibular, and tongue positions were observed through pre- and post-operative cone beam computed tomography and 3D cephalometric measurements.

RESULTS

In the camouflage orthodontic treatment group, nasopharyngeal volume and oropharyngeal volume statistically increased after treatment (P<0.05). In the orthodontic-orthognathic treatment group, changes in nasopharyngeal volume, nasopharyngeal airway, distance from posterior tongue to pharyngeal wall, palatal angle, mandibular rotation, and hyoid bone displacement were statistically significant after surgery (P<0.05). In the comparison between the two groups after treatment, changes in the distance from posterior tongue to pharyngeal wall, palatal angle, and distance from hyoid bone to sella turcica point were statistically significant (P<0.05).

CONCLUSIONS

Patients in the orthodontic-orthognathic treatment group showed significantly greater changes in oropharyngeal cross-sectional area, palate angle, and tongue position compared with patients in the camouflage orthodontic treatment group. As individuals susceptible to OSAHS often exhibit mandibular retrusion and decreased minimum airway cross-sectional area, special attention should be paid to airway morphology changes when adopting orthodontic-orthognathic treatment to avoid adverse consequences.

Predictors of orthodontic treatment preferences in a large representative UK adult cohort

Introduction The number of adults seeking orthodontic treatment globally continues to rise. This study aimed to clarify how demographic characteristics, treatment-related factors (perceived quality, cost, convenience), psychological factors (dental aesthetics, body image, mental health) and oral health influence adults' interest in pursuing orthodontic treatment.Methods A representative sample of 604 adults with the same proportion of participants as the national United Kingdom population across three core demographics (age, sex, ethnicity) completed an online survey. Data were analysed using chi-squared tests, multinomial logistic regressions, mixed analyses of variance and hierarchical multiple regression.Results A high proportion of respondents had at least some interest in pursuing orthodontic treatment and those with the greatest interest were also more likely to prefer that an orthodontist deliver this treatment. Individuals who reported a preference for an orthodontist (53% of respondents) identified treatment quality as the primary advantage and cost as the most common concern. For those who preferred direct-to-consumer aligners (25% of respondents), quality was the most common concern and convenience the primary advantage. Hierarchical multiple regression revealed that, while demographic control variables explained 10.96% of variance in respondents' interest in pursuing any type of orthodontic treatment, a model that included psychological variables and oral health explained substantial additional unique variance (20.61%; both ps <0.05). Greater negative psychosocial impact of dental aesthetics, better body image and good oral health each made significant unique contributions to predicting orthodontic interest.Conclusions These data provide a more nuanced and comprehensive understanding of the many distinct factors that influence interest in undertaking orthodontic treatment in the adult general population, with implications for ethical and consumer-centred marketing, as well as patient satisfaction and treatment adherence.

Digital Simulation and Designing of a Novel Osteotomy Guide for Autotransplantation in the Anterior Region

Autotransplantation of teeth (ATT) is a viable treatment option for replacing teeth lost due to various reasons. Periodontal ligament (PDL) on the donor tooth is one of the most crucial factors determining the success of ATT. To preserve the PDL during surgery and improve the success rate of ATT, digital dentistry has been applied to ATT. In this article, a digital workflow including surgical simulation, a three-dimensional (3D) replica fabrication, and a novel osteotomy guide design is introduced. Digital simulation of ATT on a patient's integrated model enables visualization of anatomical structures and the 3D position of the donor tooth prior to the actual surgery. The 3D-printed osteotomy guide allows the transfer of the direction and depth of the planned osteotomy into the intraoral environment. The 3D replica helps prepare the recipient site before the actual transplantation, which minimizes the extra-alveolar time of the donor tooth and decreases trauma during the try-in process. The proposed virtual planning and the use of the guide and the 3D replica can facilitate the surgical procedures while minimizing complications.

Impact of simulated gastric acid on the physical and mechanical properties of vacuum-formed retainers: an in vitro study

BACKGROUND

A decrease in oral pH levels may have detrimental effects on vacuum-formed retainers since an acidic oral environment could impact the mechanical and physical properties of these retainers. The present In vitro study aimed to evaluate the effect of simulated gastric acid at pH 4 and 1.2 on the surface microhardness, flexural strength, and color change of three different types of orthodontic retainer materials.

METHODS

A total of 144 vacuum-formed commercially available retainer materials: copolyesters, polypropylene, and PET-G (n = 48/group) were evaluated. Each specimen was immersed in distilled water, and then the specimens were divided into two subgroups: those with a pH of 4 and those with a pH of 1.2. The microhardness test was performed using Innovatest, the flexural strength was evaluated by a universal testing machine, and the color change was analyzed using a spectrophotometer. The data were analyzed using One-Way ANOVA and independent sample t test at a significance value of P ≤ 0.05.

RESULTS

Our findings indicated a significant decrease in flexural strength in all the experimental groups after immersion in pH 1.2 and 4 solutions (P < 0.001), with PET-G being the most affected material, followed by copolyester and polypropylene. Only copolyester demonstrated a significant decrease in surface microhardness following immersion in a pH 4 solution (P = 0.025). All materials exhibited the greatest degree of color alteration CP (P = 0.006), PP (P = 0.001), and PET-G (P = 0.009) respectively.

CONCLUSION

The study concluded that copolyester adversely affects flexural strength, surface microhardness, and color when subjected to immersion in simulated gastric acid. Therefore, care is recommended for patients diagnosed with gastroesophageal reflux disease.

Three-dimensional cone beam computed tomography analysis of craniofacial phenotype in nonobese apneic young adults

Objective

The obstructive sleep apnea (OSA) syndrome with its various phenotypes, as assessed by the apnea-hypopnea index (AHI), has become a major public health issue. While physicians are regularly faced with a variety of patients with OSA complaints, they may not be aware that OSA in nonobese young adults remains a largely underinvestigated topic. It is hypothesized that, in these subjects, facial bone volumes are smaller than in healthy adults.

Methods

This cross-sectional, nonrandomized, controlled study was designed to compare the 3D cephalometric analysis of bone and craniofacial soft tissues in a group of 23 nonobese apneic (AHI ≥ 15), young (18-35 years) adults and in a control group of 23 nonapneic (AHI < 15) healthy subjects by using cone beam computed tomography (CBCT). All subjects were Caucasian and underwent a sleep examination in the Sleep Clinic of the University Hospital of Liege.

Results

The two groups were comparable except for age and medications. The maxillary bone volume (23.2 ± 4.6 cm3 vs. 24.8 ± 2.9 cm3) and the mandibular bone volume (44.0 ± 6.4 cm3 vs. 46.9 ± 5.2 cm3) adjusted for demographic and biometric characteristics were significantly smaller in OSA subjects than in controls. OSA subjects had also a smaller angle of the maxillary diagonals (95.3 ± 13.9° vs. 106 ± 15.9°) and, at the mandible, a narrower width (90.8 ± 8.0 mm vs. 95.1 ± 5.3 mm), a wider gonial angle (119.9 ± 5.5° vs. 116.5 ± 4.4°), a longer ramus (51.2 ± 6.6 mm vs. 47.3 ± 5.0 mm), and a shorter corpus (74.1 ± 10.3 mm vs. 78.9 ± 5.8 mm) than controls.

Conclusion

Craniofacial structures that most discerned apneic subjects from controls were the maxillary and mandible bone volumes. An overly narrow maxilla and a postero-rotating mandible were also associated with OSA.

Level of Evidence

III.

Registration

NCT06022679.

Association Between Different Biomarkers and Initial Orthodontic Tooth Movement in Children and Adults: A Systematic Review and Meta-Analysis

The present systematic review aims to bridge the existing knowledge gap by evaluating the influence of various biomarkers on initial orthodontic tooth movement in children and adults. A systematic electronic search was conducted using relevant keywords across the databases PubMed, Google Scholar, and EBSCOhost to identify articles published in English until December 2023. The "Risk of Bias (ROB) in Non-randomized Studies of Interventions" (ROBINS-I) tool was used to assess the risk of bias, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was applied to critically appraise the quality of evidence. A total of 10 studies were identified, all of which were non-randomised clinical trials that compared biomarker expression in patients belonging to the growing age group (children, juveniles, or adolescents) and adults, using gingival crevicular fluid (GCF) or saliva analysed by the ELISA method. Overall, younger patients consistently exhibited faster and more pronounced biological responses to orthodontic forces, with biomarker levels peaking within the first 72 hours of force application.

Predicting the Risk of Maxillary Canine Impaction Based on Maxillary Measurements Using Supervised Machine Learning

OBJECTIVES

To predict palatally impacted maxillary canines based on maxilla measurements through supervised machine learning techniques.

MATERIALS AND METHODS

The maxilla images from 138 patients were analysed to investigate intermolar width, interpremolar width, interpterygoid width, maxillary length, maxillary width, nasal cavity width and nostril width, obtained through cone beam computed tomography scans. The predictive models were built using the following machine learning algorithms: Adaboost Classifier, Decision Tree, Gradient Boosting Classifier, K-Nearest Neighbours (KNN), Logistic Regression, Multilayer Perceptron Classifier (MLP), Random Forest Classifier and Support Vector Machine (SVM). A 5-fold cross-validation approach was employed to validate each model. Metrics such as area under the curve (AUC), accuracy, recall, precision and F1 Score were calculated for each model, and ROC curves were constructed.

RESULTS

The predictive model included four variables (two dental and two skeletal measurements). The interpterygoid width and nostril width showed the largest effect sizes. The Gradient Boosting Classifier algorithm exhibited the best metrics, with AUC values ranging from 0.91 [CI95% = 0.74-0.98] for test data to 0.89 [CI95% = 0.86-0.94] for crossvalidation. The nostril width variable demonstrated the highest importance across all tested algorithms.

CONCLUSION

The use of maxillary measurements, through supervised machine learning techniques, is a promising method for predicting palatally impacted maxillary canines. Among the models evaluated, both the Gradient Boosting Classifier and the Random Forest Classifier demonstrated the best performance metrics, with accuracy and AUC values exceeding 0.8, indicating strong predictive capability.

Antimicrobial Effects of Orthodontic Molar Tube Coated with ZnO Nanoparticles Using Electrophoretic Deposition Method: A Randomized Clinical Trial

This study aimed to evaluate the antimicrobial effect of coated orthodontic molar tubes (COMT) with zinc oxide nanoparticles (ZnO NPs) using an electrophoretic deposition method (EPD) and to evaluate the orthodontic molar tubes (OMT) bond failure rate. Seventy-two orthodontic molar tubes (OMTs) for second molars were divided into two groups 36 each; one group coated with ZnO NPs and the other control negative uncoated. The OMT was coated using the EPD method with ZnO NPs in a concentration of 10 g/l. The OMTs were randomly allocated using a split-mouth, cross-quadrant design. After 2 weeks of appliance placement, swabs were taken from the surface of the OMTs for microbial assessment against Streptococcus mutans, Lactobacillus acidophilus, and total bacterial counts; additionally, plaque and gingival indices were assessed. The patient was followed for 3 months to evaluate the bond failure rate. The COMT showed a statistically significant reduction in total bacterial accounts, S. mutans, and L. acidophilus compared to UOMT (P < 0.001). Furthermore, the plaque and gingival indices near COMT were significantly less than that of UOMT. The bond failure rate was not significant between the COMT and UOMT. The COMT with ZnO NPs has potent antibacterial activity against the tested pathogens with a reduction in the amount of plaque accumulation. The use of the EPD method was feasible without adverse effects on the orthodontic molar tubes bond failure rate.

Eco-Conscious Orthodontics: A Greener Approach to Dental Care

With the advancing world, where the medical and dental fields are progressing every day toward better and finer diagnosis and treatment modalities to enhance and provide better standards of life, it becomes important for medical and dental professionals to consider the environment and apply environmental sustainability measures moving towards a better future. One such practice is green dentistry, where "reduce, reuse, rethink, and recycle" are being implemented and, similarly, "eco-friendly" dentistry, which recommends the use of "ask, assess, advice, and assist." With the same concept of keeping in the limelight, green orthodontics gives us an idea of reducing, reusing, rethinking, and recycling materials and products to bring about a more sustainable and better future.