Patients' perceptions matter: Risk communication and psychosocial factors in orthodontics.

INTRODUCTION: Effective risk communication is essential for achieving patient-centered oral health care, but the limited understanding of patients' subjective perceptions of orthodontic-related risks hinders this process. This study aimed to investigate adults' awareness, concerns, and risk-avoidance behaviors about long-term orthodontic risks, exploring their relationship with psychosocial factors. METHODS: We included 498 adult patients (mean age, 27.3 ± 6.8 years; women, 75.5%) during their initial visits to the orthodontic department at a hospital in Chengdu, China. Participants' understanding of orthodontic risks was gauged before and after exposure to the Oral Health Education Comics (OHEC), a specifically designed digital tool. Concurrently, we used logistic regression models to investigate the associations between patients' depression, anxiety, self-esteem, perfectionism, and dentofacial esthetics with risk perceptions. RESULTS: Approximately 79.5% of participants initially reported low awareness of orthodontic risks, with most knowledge from online sources. Notably, the percentage of participants with high awareness increased to 64.8% after OHEC. The negative facial soft-tissue change was most concerning for participants: 53.4% showed high concerns, and 28.1% showed high avoidance. Furthermore, linear regression indicated positive associations between depression (ß = 0.42 [95% confidence interval {CI}, 0.07-0.77]) and anxiety (ß = 0.76 [95% CI, 0.35-1.18]) with orthodontic risk concerns, whereas risk avoidance was positively associated with depression (ß = 0.62 [95% CI, 0.27-0.97]), anxiety (ß = 1.09 [95% CI, 0.68-1.50]), and perfectionism (ß = 0.24 [95% CI, 0.02-0.46]). CONCLUSIONS: Findings emphasize the imperative of streamlined risk communication in orthodontics. By incorporating comprehensible tools such as OHEC and integrating psychosocial evaluations, more refined patient-practitioner communication and psychosomatic-based dental care can be achieved.

Finite element analysis of the biomechanical effect of clear aligners in extraction space closure under different anchorage controls.

INTRODUCTION: Clear aligners (CAs) have attracted increasing attention from patients and orthodontists because of their excellent esthetics and comfort. However, treating tooth extraction patients with CAs is difficult because their biomechanical effects are more complicated than those of traditional appliances. This study aimed to analyze the biomechanical effect of CAs in extraction space closure under different anchorage controls, including moderate, direct strong, and indirect strong anchorage. It could provide several new cognitions for anchorage control with CAs through finite element analysis, further directing clinical practice. METHODS: A 3-dimensional maxillary model was generated by combining cone-beam computed tomography and intraoral scan data. Three-dimensional modeling software was used to construct a standard first premolar extraction model, temporary anchorage devices, and CAs. Subsequently, finite element analysis was performed to simulate space closure under different anchorage controls. RESULTS: Direct strong anchorage was beneficial for reducing the clockwise occlusal plane rotation, whereas indirect anchorage was conducive for anterior teeth inclination control. In the direct strong anchorage group, an increase in the retraction force would require more specific anterior teeth overcorrection to resist the tipping movement, mainly including lingual root control of the central incisor, followed by distal root control of the canine, lingual root control of the lateral incisor, distal root control of the lateral incisor, and distal root control of the central incisor. However, the retraction force could not eliminate the mesial movement of the posterior teeth, possibly causing a reciprocating motion during treatment. In indirect strong groups, when the button was close to the center of the crown, the second premolar presented less mesial and buccal tipping but more intrusion. CONCLUSIONS: The 3 anchorage groups showed significantly different biomechanical effects in both the anterior and posterior teeth. Specific overcorrection or compensation forces should be considered when using different anchorage types. The moderate and indirect strong anchorages have a more stable and single-force system and could be reliable models in investigating the precise control of future tooth extraction patients.

PTH/PTHrP in controlled release hydrogel enhances orthodontic tooth movement by regulating periodontal bone remodaling.

OBJECTIVE: This study aimed to evaluate the effects of local application of parathyroid hormone (PTH) or parathyroid hormone-related protein (PTHrP) on osteogenesis and osteoclastogenesis during orthodontic tooth movement (OTM). BACKGROUND: Periodontal bone remodeling is the crucial biological process in the OTM that involves both bone resorption and formation, with the former more important as the initiator. PTH or PTHrP both play dual roles in bone remodeling regulation, and the balance may shift to the bone resorption side when they are given continuously, suggesting them as potential candidate medicine for OTM acceleration. METHODS: A total of 40 rats underwent orthodontic mesialization of the maxillary first molars and received no micro-perforation (MOP), or MOP followed by injection of temperature-sensitive hydrogel containing PTH, PTHrP, or normal saline. The rats were sacrificed after 2-week OTM, except for the relapse groups, which had one more week of observation after removal of the force appliances. The amount of tooth movement, rate of relapse after OTM, and effects on the bone remodeling were assessed through micro-computed tomography (µCT) analysis, alkaline phosphatase (ALP) assay, alizarin red staining, tartrate-resistant acid phosphatase (TRAP) staining, immunohistochemistry (IHC) analysis, Western blot (WB), and quantitative real-time polymerase chain reaction (qRT-PCR). The effects of PTHrP on the osteogenic differentiation of human periodontal ligament cells (hPDLCs) were explored in vitro. RESULTS: The cumulative release of PTH or PTHrP from PECE hydrogels was beyond 75% at 14 days in a sustained manner. After the intervention in vivo, the distance of OTM in the PTH (0.78 ± 0.06 mm) or PTHrP (0.81 ± 0.04 mm) group was significantly larger than that of the MOP only (0.51 ± 0.04 mm) or the no MOP (0.46 ± 0.05 mm) group. Moreover, PTH injection significantly reduced the rate of relapse after OTM (25.7 ± 4.3%) compared to the control (69.6 ± 6.1%). µCT analysis showed decreased BV/TV, BS/BV, and Tb.N, while increased Tb.Sp of alveolar bone in the PTH or PTHrP group. There were also more TRAP-positive osteoclasts in the PTH or PTHrP group with a significantly enhanced ratio of receptor activator of nuclear factor-κB ligand (RANKL)/osteoprotegerin (OPG). The protein expressions of PTH/PTHrP type 1 receptor (PTHR1), alkaline phosphatase (ALP), osteocalcin (OCN), runt-related transcription factor 2 (RUNX2), and ß-catenin were significantly increased in the PTH or PTHrP group, as well as the gene expressions of Pth1r, Bglap, and Alpl. There was no significant difference between the effects of PTH and PTHrP. Nevertheless, inhibition of PTHrP on the osteogenic differentiation of hPDLCs was detected in vitro with decreased expression of OCN, RUNX2, COL-1, and ALP. CONCLUSION: Local injection of either PTH or PTHrP carried by controlled release PECE hydrogel similarly enhances OTM in rats through regulating periodontal bone remodeling, which deserves further study for potential clinical application.

Orthodontic incisor retraction caused changes in the soft tissue chin area: a retrospective study.

BACKGROUND: To investigate the area and morphological changes around the soft tissue chin after orthodontic incisor retraction. METHODS: Fifty-nine female adults with bimaxillary protrusion requiring extraction of four premolars were included in the study. Cephalograms were taken before (T0) and after (T1) orthodontic treatment. The soft tissue changes, including the area, thickness and morphology were measured. Paired-t tests were performed for statistical comparisons. Pearson correlation analyses and backward multivariate regression analyses were used to identify the relationship between the soft tissue changes and incisor retraction. RESULTS: Following the incisor retractions (5.35 ± 1.79 mm and 4.42 ± 1.62 mm for the upper and lower, respectively), there was a significant increase in the soft tissue thickness of L1c-LL (0.64 ± 1.67 mm, P = 0.025) and Pog-Pog' (0.44 ± 1.10 mm, P = 0.022), and a significant decrease in the soft tissue thickness of B-B' (1.21 ± 1.34 mm, P <  0.01). Changes in the area of soft tissue chin and lower lip were not statistically significant (P > 0.05). Pearson coefficient between the thickness changes of B-B' and the retraction of lower incisors was - 0.376. The multiple correlations between the soft tissue thickness changes and incisor retractions were Y = 1.02-0.42a + 0.42b for L1c-LL, and Y = 0.17-0.31b for B-B'. CONCLUSIONS: The orthodontic incisor retraction could cause soft tissue thickness changes (i.e. an increase in L1c-LL and Pog-Pog' and a decrease in B-B') without area changes.

Proteomic analysis of human periodontal ligament cells under hypoxia.

BACKGROUND: The periodontal ligament is essential for homeostasis of periodontal tissue. A hypoxic milieu of the periodontal tissue is generated under periodontitis or during orthodontic treatment, which affects the periodontal and bone remodelling process. Here, we provide a comprehensive proteomic characterization of periodontal ligament cells under hypoxic conditions, aiming to reveal previously unappreciated biological changes and to help advance hypoxia-based therapeutic strategies for periodontal diseases. METHODS: Human periodontal ligament cells (hPDLCs) were characterized using immunohistochemistry (IHC) and flow cytometry (FACS). Successful hypoxia treatment of hPDLCs with 1% O2 was confirmed by qRT-PCR. Proliferation was evaluated using an MTT assay. The proteomic expression profile under hypoxia was studied with the isobaric tags for relative and absolute quantification (iTRAQ) approach followed by protein identification and bioinformatic analysis, and western blot verification was performed. RESULTS: The hPDLCs were positive for vimentin, CD73 and CD105 and negative for keratin, CD34 and CD45. After hypoxia treatment, the mRNA expression of hypoxia-inducible factor 1a (HIF1a) was upregulated. The proliferation rate was elevated during the first 6 h but decreased from 6 h to 72 h. A total of 220 differentially expressed proteins were quantified in hPDLCs under hypoxia (1% O2, 24 h), including 153 upregulated and 67 downregulated proteins, five of which were verified by western blot analysis. The Gene Ontology enriched terms included the energy metabolic process, membrane-bound organelle and vesicle, and protein binding terms. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated several involved pathways, including glycolysis/gluconeogenesis, biosynthesis of amino acids, the HIF-1 signalling pathway, and focal adhesion. A protein-protein interaction (PPI) network demonstrated the dominant role of autophagy over apoptosis under hypoxia. CONCLUSION: The proteomic profile of hPDLCs under hypoxia was mainly related to energy metabolism, autophagy, and responses to stimuli such as adhesion and inflammation. Previously unrecognized proteins including solute carrier family proteins, heat shock proteins, ubiquitination-related enzymes, collagen and S100 family proteins are involved in adaptive response to hypoxia in hPDLCs and are thus of great research interest in future work.

Effect of conventional combined orthodontic-surgical treatment on oral health-related quality of life: A systematic review and meta-analysis.

INTRODUCTION: Although conventional combined orthodontic-surgical treatment is frequently applied in orthodontic clinic practice, its actual effect on oral health-related quality of life (OHRQoL) remains inconclusive. We aimed to appraise trials investigating the effect of conventional combined orthodontic-surgical treatment on OHRQoL in patients with dentofacial deformities. METHODS: Electronic searches of 6 databases and manual searches were conducted up to January 2019. Randomized controlled trials, controlled clinical trials, and prospective cohort studies that investigated the impact of combined orthodontic-surgical treatment on OHRQoL using validated instruments were included. The risk of bias within individual studies was assessed with the use of the Cochrane tool or the Newcastle-Ottawa Scale according to study designs. Meta-analysis was conducted, and OHRQoL at different time points during conventional combined orthodontic-surgical treatment were statistically pooled and compared. RESULTS: Of the 893 records initially identified, 24 studies were included in this review. Relative to pretreatment, the condition-specific OHRQoL was significantly improved 6 months after surgery, particularly in the perceptions to social aspects (mean difference [MD] 4.88, 95% confidence interval [CI] 2.45 to 7.32), facial appearance (MD 5.48, 95% CI 4.18 to 6.79), and oral function (MD 4.49, 95% CI 3.27 to 5.72). In terms of changes during combined orthodontic-surgical treatment, the condition-specific OHRQoL worsened in the presurgical orthodontic treatment (MD -7.25, 95% CI -13.29 to -1.22) and improved postsurgically compared with pretreatment (MD 16.59, 95% CI 10.41 to 22.77). Similar patterns were observed in the general OHRQoL changes. CONCLUSIONS: For patients undergoing combined orthodontic-surgical treatment, the OHRQoL seems to decrease temporarily in presurgical orthodontic treatment compared with pretreatment and to increase to a level better than it was before treatment during postsurgical orthodontic treatment. Based on the present review, combined orthodontic-surgical treatment could be an effective choice to improve OHRQoL for patients affected with severe dentofacial deformities.

A novel totally biodegradable device for effective atrial septal defect closure: A 2-year study in sheep.

OBJECTIVE: To evaluate the feasibility, efficacy, and safety of a fully biodegradable poly lactic acid (PLA)-based occluder for atrial septal defect (ASD) closure in an animal model. METHODS: ASDs, approximately 12-mm in diameter, were generated in sheep (n = 18) by needle puncture and balloon dilatation. For ASD closure, occluders were implanted by percutaneous transcatheter approach under echocardiographic guidance. Outcomes were evaluated by transthoracic echocardiography, electrocardiography, blood testing, and histology within the follow-up period ranging from 1 month to 2 years. RESULTS: All occluders were successfully implanted. During follow-up, no animal died; rectal temperatures, blood test results, and electrocardiograms were within normal ranges; and transthoracic echocardiograms, macroscopic studies, and histopathological and electron microscopic examination demonstrated that the occluders were well positioned, with no shifting, residual shunts, severe inflammation, thrombus formation, atrioventricular valve insufficiency, cardiac erosion or arrhythmias. The occluders gradually embedded into the endocardial tissue of the hosts with complete endothelialization and disk absorption at 12 months, and a distinct molecular weight decrease of the framework (to 9% of initial) at 24 months after implantation. CONCLUSIONS: In a sheep model, the use of totally biodegradable occluders appears feasible, efficacious and safe for ASD closure. Studies in humans are ongoing.

Analysis of oral microbial community and Th17-associated cytokines in saliva of patients with oral lichen planus.

Oral lichen planus (OLP) is a chronic inflammatory disorder of oral mucosa of unknown cause. Microbial infection and dysimmunity appear to play important roles in its pathogenesis. In this study, differences in genetic profiling of salivary microbial communities in two subtypes of OLP and healthy controls were evaluated by means of PCR-denaturing gradient gel electrophoresis (DGGE). Additionally, ELISA was used to investigate the possible role of Th17 in lesion formation by detecting two related cytokines IL-17 and IL-23 in the saliva of OLP patients. When the DGGE profiles were analyzed, the bacterial populations were found to be significantly less rich in subjects with reticular and erosive OLP than in healthy controls. There was significantly less microbial diversity, as denoted by the Shannon index, in saliva samples from subjects with erosive OLP than in those from healthy controls. Cluster analysis and principal component analysis showed that the DGGE profiles formed distinctly group-specific clusters. Salivary concentrations of IL-17 in subjects with erosive OLP group were significantly higher than in those with reticular OLP and healthy controls. What's more, significantly positive correlations were observed between salivary IL-17 concentrations and disease clinical scores. Microbial richness and diversity was negatively correlated with salivary IL-17 concentrations. These results suggest there is significantly less salivary bacterial diversity and complexity in subjects with OLP han in healthy controls and that the shifted community composition is closely related to an immune cytokine, IL-17.

Comparison of near-infrared imaging with cone-beam computed tomography for proximal caries detection in permanent dentition: An in vivo study.

OBJECTIVES: This study aimed to evaluate the diagnostic performance of near-infrared imaging (NIRI) and unaided visual examination (UVE) in detecting proximal caries in permanent dentition in comparison with cone-beam computed tomography (CBCT). METHODS: Patients who underwent NIRI, UVE, and CBCT imaging within 1 week were enrolled. Using CBCT as the reference test, the positive percent agreement (PPA), negative percent agreement (NPA), and overall percent agreement (OPA) of NIRI, UVE, and a combination of the two for detecting proximal caries at different depths and in different tooth locations were assessed. Additionally, the consistency of these diagnostic methods with CBCT was evaluated. RESULTS: We evaluated 6,084 proximal surfaces and identified 177 CBCT-positive sites. NIRI had a PPA, NPA, and OPA of 68.93 %, 99.09 %, and 98.21 %, respectively, with a substantial agreement with CBCT. When combined with UVE, the PPA increased by approximately 50 % compared with that of UVE alone. Regarding caries at different depths, NIRI outperformed UVE in detecting initial caries (ICDAS 1-2) over moderate-to-advanced caries (ICDAS 3-6). However, the combined use of NIRI and UVE improved the detection of moderate-to-advanced caries. In the anterior teeth region, NIRI exhibited excellent agreement with CBCT, surpassing its performance in the posterior region. CONCLUSIONS: Although NIRI cannot fully replace radiographic methods, the substantial agreement of NIRI with CBCT in detecting proximal caries highlights its potential as a complementary tool in routine caries screening, especially when combined with UVE. CLINICAL SIGNIFICANCE: This study highlights the potential of NIRI as a radiation-free method for detecting proximal caries in permanent teeth. Early detection through regular NIRI scanning can lead to timely intervention, improved patient outcomes, and reduced overall disease burden.

Sclerostin injection enhances orthodontic tooth movement in rats.

OBJECTIVE: It was aimed to investigate the in vivo effects of local injection of sclerostin protein on orthodontic tooth movement. DESIGN: A total of 48 rats underwent orthodontic mesialization of the maxillary first molars on both sides. Local injection was given at the compression side in the alveolar bone on both maxillary sides, with sclerostin protein carried by hydrogel on one side, and the same volume of normal saline carried by hydrogel on the other side serving as the control. After two weeks, the tooth movement amount and effects on the periodontium were assessed through micro-computed tomography (µCT) analysis, tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemistry (IHC) analysis. RESULTS: After two weeks of intervention, tooth movement was significantly greater in the 4 µg/kg and 20 µg/kg sclerostin injection groups, compared to the control. Analysis of the furcation area of the maxillary first molar showed that the 20 µg/kg group had significantly decreased BV/TV. At the compression side, the number of TRAP-positive osteoclasts was significantly increased in 20 µg/kg group compared to the control. The expression of RANKL was statistically higher in all the sclerostin groups, while the expression of OPG was statistically lower in the 4 µg/kg and 20 µg/kg groups, compared to the control. At the tension side, the expression of RUNX2 and COL-1 was statistically higher in the 20 µg/kg group compared to the control. CONCLUSIONS: Local injection of sclerostin protein in the alveolar bone at the compression side accelerates OTM in rats by promoting osteoclastogenesis.

Colour stabilities of three types of orthodontic clear aligners exposed to staining agents.

The aim of this study was to evaluate and compare the colour stabilities of three types of orthodontic clear aligners exposed to staining agents in vitro. Sixty clear orthodontic aligners produced by three manufacturers (Invisalign, Angelalign, and Smartee) were immersed in three staining solutions (coffee, black tea, and red wine) and one control solution (distilled water). After 12-h and 7-day immersions, the aligners were washed in an ultrasonic cleaner and measured with a colourimeter. The colour changes (ΔE*) were calculated on the basis of the Commission Internationale de I'Eclairage L*a*b* colour system (CIE L*a*b*), and the results were then converted into National Bureau of Standards (NBS) units. Fourier transformation infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) were conducted to observe the molecular and morphologic alterations to the aligner surfaces, respectively. The three types of aligners exhibited slight colour changes after 12 h of staining, with the exception of the Invisalign aligners stained with coffee. The Invisalign aligners exhibited significantly higher ΔE* values (ranging from 0.30 to 27.81) than those of the Angelalign and Smartee aligners (ΔE* values ranging from 0.33 to 1.89 and 0.32 to 1.61, respectively, P<0.05). FT-IR analysis confirmed that the polymer-based structure of aligners did not exhibit significant chemical differences before and after the immersions. The SEM results revealed different surface alterations to the three types of aligner materials after the 7-day staining. The three types of aesthetic orthodontic appliances exhibited colour stability after the 12-h immersion, with the exception of the Invisalign aligners stained by coffee. The Invisalign aligners were more prone than the Angelalign and Smartee aligners to pigmentation. Aligner materials may be improved by considering aesthetic colour stability properties.

Preliminary analysis of salivary microbiome and their potential roles in oral lichen planus.

Several studies have explored the origin and development mechanism of oral lichen planus (OLP) with limited attention to the role of bacteria in the progression of this common oral disease. Here we utilized MiSeq sequencing of 16S rRNA gene amplicons to identify complex oral microbiota associated with OLP from saliva samples of two subtypes (reticular and erosive) of OLP patients and healthy controls. Our analyses indicated that the overall structure of the salivary microbiome was not significantly affected by disease status. However, we did observe evident variations in abundance for several taxonomic groups in OLP. Porphyromonas and Solobacterium showed significantly higher relative abundances, whereas Haemophilus, Corynebacterium, Cellulosimicrobium and Campylobacter showed lower abundances in OLP patients, as compared with healthy controls. In addition, we explored specific microbial co-occurrence patterns in OLP, and revealed significantly fewer linkers of Streptococcus comprising species in erosive OLP. Furthermore, the disease severity and immune dysregulation were also genus-associated, including with Porphyromonas that correlated to disease scores and salivary levels of interleukin (IL)-17 and IL-23. Overall, this study provides a general description of oral microbiome in OLP, and it will be useful for further investigation of their potential roles in the initiation and immune modulation of OLP.

[Isolation and identification of aerobic and facultative anaerobic bacteria in the oral cavity].

OBJECTIVE: To establish a systematic method for isolation and identification of aerobic and facultative anaerobic bacteria in the oral cavity. METHODS: Samples of the saliva, dental plaque and periapical granulation tissue were collected from 20 subjects with healthy oral condition and from 8 patients with different oral diseases. The bacteria in the samples were identified by morphological identification, VITEK automatic microorganism identification and 16s rRNA gene sequencing. RESULTS: VITEK automatic microorganism identification and 16s rRNA gene sequencing showed an agreement rate of 22.39% in identifying the bacteria in the samples. We identified altogether 63 bacterial genus (175 species), among which Streptococcus, Actinomyces and Staphylococcus were the most common bacterial genus, and Streptococcus anginosus, Actinomyces oris, Streptococcus mutans and Streptococcus mitis were the most common species. Streptococcus anginosus was commonly found in patients with chronic periapical periodontitis. Streptococcus intermedius and Staphylococcus aureus were common in patients with radiation caries, and in patients with rampant caries, Streptococcus mutans was found at considerably higher rate than other species. CONCLUSION: Aerobic and facultative anaerobic bacteria are commonly found in the oral cavity, and most of them are gram-positive. 16s rRNA gene sequencing is more accurate than VITEK automatic microorganism identification in identifying the bacteria.