Niansong Ye

Cognitive Behavioral Therapy for Orthodontic Pain Control A Randomized Trial

The objective of this study was to evaluate the efficacy of cognitive behavioral therapy intervention for patients who experienced pain during orthodontic treatment. The baseline characteristics were assessed via questionnaires and oral examinations. Four hundred and fifty eligible individuals were recruited and randomized by computer-generated block randomization into three groups: cognitive behavioral therapy intervention (n = 150), ibuprofen intervention (n = 150), and no intervention (control; n = 150). Primary outcomes were the change from baseline in pain intensity measured with 100-mm Visual Analog Scale (VAS) scores at 1, 2, 3, 7, 14, and 30 days after initial archwire placement. Outcomes assessment was blinded and followed the intention-to-treat principle. One hundred forty-three (95.30%), 145 (96.70%), and 141 (94.00%) individuals in the cognitive behavioral therapy, the ibuprofen, and the control groups, respectively, completed the one-month follow-up evaluations. Those in the cognitive behavioral therapy group showed a greater decrease in mean VAS scores than did those in the control group over the previous five time-points (p < 0.001). Cognitive behavioral therapy was shown to be effective in pain control during the initial stage of orthodontic treatment. The study registration number was ChiCTR-TRC-00000556.

Absorption, Pharmacokinetics and Disposition Properties of Solid Lipid Nanoparticles (SLNs)

In recent years, many researchers have paid more and more attentions on the use of Nanotechnology. Solid lipid nanoparticles (SLNs) are emerged as a promising alternation herein to emulsions, liposomes, microparticles and polymeric nanoparticles for their advantages. As promising drug carrier systems, SLNs are valuable for nanomedicine and have been widely used as delivery systems mostly for drugs and macromolecules like proteins, oligonucleotides and DNA by various application routes, such as intravenous, oral, duodenalous, intramuscular, pulmonary, intranasal, ocular, rectal and intraperitoneal administrations. It has been shown that SLNs can increase bioavailability, alter pharmacokinetic parameters and tissue distribution of the drug loaded. In this review, we will primarily focus on the absorption, pharmacokinetics and disposition properties of SLNs for their possible applications in drug delivery.

Accuracy of in-vitro tooth volumetric measurements from cone-beam computed tomography

INTRODUCTION The aims of this study were to determine the accuracy of volumetric measurements of teeth in vitro by cone-beam computed tomography (CBCT) and to analyze the factors affecting their volume measurements from the CBCT data. METHODS We used a sample of CBCT-scanned (voxel sizes: 0.125, 0.20, 0.25, 0.30, and 0.40 mm) and laser-scanned crowns (n = 40) and roots (n = 32). The Tukey test was used to assess the differences between the CBCT-scan and the laser-scan volumes. RESULTS There was a statistically significant difference between the laser-scan crown volume and each voxel size of CBCT-scan crown volume (P <0.05). CBCT-scan crown volumes at 0.30 and 0.40 mm were statistically significantly distinct from those at 0.125, 0.20, and 0.25 mm (P <0.05). There was a statistically significant difference between the laser-scan root volume and each voxel size of CBCT-scan root volume (P <0.05). The laser-scan root volume at 0.40 mm was statistically significantly distinct from the volumes at 0.125 and 0.20 mm (P <0.05). The in-vitro volume measurements from the CBCT scans were larger than those of the laser scans: from 21.73% to 43.92% in the crown halves, and from 18.27% to 41.58% in the root halves at the different voxel sizes. CONCLUSIONS With increasing voxel sizes during scanning, the volume measurements of teeth tended to be larger. The surface surrounding artifacts might lead to larger volumes.

Evaluation of pain in rats through facial expression following experimental tooth movement

This study was carried out to evaluate pain in rats by monitoring their facial expressions following experimental tooth movement. Male Sprague-Dawley rats were divided into the following five groups based on the magnitude of orthodontic force applied and administration of analgesics: control; 20 g; 40 g; 80 g; and morphine + 40 g. Closed-coil springs were used to mimic orthodontic forces. The facial expressions of each rat were videotaped, and the resulting rat grimace scale (RGS) coding was employed for pain quantification. The RGS score increased on day 1 but showed no significant change thereafter in the control and 20-g groups. In the 40- and 80-g groups, the RGS scores increased on day 1, peaked on day 3, and started to decrease on day 5. At 14 d, the RGS scores were similar in control and 20-, 40-, and 80-g groups and did not return to baseline. The RGS scores in the morphine + 40-g group were significantly lower than those in the control group. Our results reveal that coding of facial expression is a valid method for evaluation of pain in rats following experimental tooth movement. Inactivated springs (no force) still cause discomfort and result in an increase in the RGS. The threshold force magnitude required to evoke orthodontic pain in rats is between 20 and 40 g.

Comparison of adverse effects between lingual and labial orthodontic treatment A systematic review

OBJECTIVE To compare adverse effects between labial and lingual orthodontic treatments through a systematic review of the literature. MATERIALS AND METHODS The protocol of this systematic review (CRD42012002455) was registered in the International Prospective Register of Systematic Reviews (PROSPERO). An electronic search was conducted in PubMed, Embase, Web of Science, CENTRAL, SIGLE, ProQuest Dissertations & Theses, and ClinicalTrial.gov for articles published between January 1980 and December 2012. Primary outcomes included pain and caries; secondary outcomes were eating difficulty, speech difficulty, oral hygiene, and treatment duration. Meta-analyses were conducted in Comprehensive Meta-Analysis version 2.2.064. RESULTS Six studies were included, two randomized controlled trials and four clinical controlled trials; of these, four were medium quality and two were low quality in terms of the risk of bias. Five of the six outcomes were evaluated in the included studies, and treatment duration was not; pain, eating difficulty, speech difficulty were statistically pooled. Meta-analysis revealed that the pooled odds ratios were 1.20 (95% confidence interval [CI]  =  0.30-4.87) for overall pain, 32.24 (95% CI  =  14.13-73.55) for pain in tongue, 0.08 (95% CI  =  0.04-0.18) for pain in cheek, 0.11 (95% CI  =  0.03-0.42) for pain in lip, 3.59 (95% CI  =  1.85-6.99) for eating difficulty, and 8.61 (95% CI  =  3.55-20.89) for speech difficulty. Sensitivity analysis showed consistent results except for eating difficulty. No publication bias was detected. CONCLUSIONS The likelihood of overall pain was similar between the two modalities. Patients who underwent lingual orthodontic treatment were more likely to suffer from pain in the tongue and less likely to suffer from pain in the cheek and lip. Lingual orthodontic treatment increased the likelihood of speech difficulty. Eating difficulty, oral hygiene, caries, and treatment duration could not be compared in this systematic review.

Diagnostic accuracy of CBCT for tooth fractures: A meta-analysis

OBJECTIVES The objective of this meta-analysis was to determine the diagnostic accuracy of cone-beam computed tomography (CBCT) for tooth fractures in vivo. METHODS PubMed, Embase, Web of Science, ProQuest Dissertations & Theses, CNKI and SIGLE were searched from January 1990 to April 2013 for eligible studies. Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) was employed to assess the quality of the included studies. Meta-analyses were performed in MetaDisc 1.4, Stata 12.1 and StatsDirect 2.7.9. RESULTS Finally, 12 studies were included in this meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and summary receiver operating characteristic were 0.92 (95% CI=0.89-0.94), 0.85 (95% CI=0.75-0.92), 5.68 (95% CI=3.42-9.45), 0.13 (95% CI=0.09-0.18) and 0.94 (95% CI=0.90-0.98), respectively. The pooled prevalence of tooth fractures in patients with clinically-suspected but periapical-radiography-undetected tooth fractures was 91% (95% CI=83%-97%). Positive and negative predictive values were 0.98 and 0.43 (subgroup analysis: 0.98 and 0.28 for endodontically-treated teeth; 0.99 and 0.77 for non-endodontically-treated teeth). CONCLUSION We suggest that CBCT has a high diagnostic accuracy for tooth fractures and could be used in clinical settings. We can be very confident with positive test results but should be very cautious with negative test results, especially for endodontically treated teeth.

The effectiveness of the Herbst appliance for patients with Class II malocclusion: a meta-analysis

OBJECTIVE To systematically investigate review in literature the effects of the Herbst appliance for patients with Class II malocclusion patients. METHOD We performed a comprehensive literature survey on PubMed, Web of Science, Embase, CENTRAL, SIGLE, and ClinicalTrial.gov up to December 2014. The selection criteria: randomized controlled trials or clinical controlled trials; using any kind of Herbst appliances to correct Class II division 1 malocclusions; skeletal and/or dental changes evaluated through lateral cephalograms. And the exclusion criteria: syndromic patients; individual case reports and series of cases; surgical interventions. Article screening, data extraction, assessment of risk of bias, and evaluation of evidence quality through GRADE were conducted independently by two well-trained orthodontic doctors. Consensus was made via group discussion of all authors when there is inconsistent information from the two. After that, sensitivity analysis and subgroup analysis were performed to evaluate the robustness of the meta-analysis. RESULTS Twelve clinical controlled trials meet the above-mentioned criteria, and were included in this analysis. All included studies have eleven measures taken during both active treatment effect and long term effect periods, including four angular ones (i.e., SNA, SNB, ANB, mandibular plane angle) and seven linear ones (i.e. Co-Go, Co-Gn, overjet, overbite, molar relationship, A point-OLp, Pg-OLp) during active treatment effect period were statistically pooled. Meta-analysis and sensitivity analysis demonstrated that all these measures showed consistent results except for SNA, ANB, and overbite. Subgroup analysis showed significant changes in SNA, overbite, and Pg-OLp. Publication bias was detected in SNB, mandibular plane angle, and A point-OLp. CONCLUSION The Herbst appliance is effective for patients with Class II malocclusion in active treatment period. Especially, there are obvious changes on dental discrepancy and skeletal changes on Co-Gn. As to its long-term effects, more evidence is needed to draw conclusions.

The effectiveness of non-surgical maxillary expansion: a meta-analysis

OBJECTIVE To evaluate and compare the effectiveness of rapid maxillary expansion (RME) and slow maxillary expansion (SME). MATERIALS AND METHODS PubMed, Embase, Web of Science, CENTRAL, ProQuest Dissertations & Theses, ClinicalTrial.gov, and SIGLE were searched from January 1980 to October 2012 for randomized or non-randomized controlled trials. The processes of study search, selection, and quality assessment were conducted independently and in duplicate. Original outcome data underwent statistical pooling through Review Manager 5. RESULTS Fourteen eligible studies were finally included and two interventions (RME and SME) studied. Four outcomes (maxillary intermolar width, maxillary intercanine width, maxillary interpremolar width, and mandibular intermolar width) during three time periods (expansion, retention, and net change) were statistically pooled. The sensitivity analysis revealed that the results from the meta-analysis were generally robust. Eggers test and Beggs test detected no publication bias except for maxillary intercanine width in expansion period for SME versus control. CONCLUSIONS SME is effective in expanding maxillary arch, while we cannot determine its effectiveness in mandibular arch expansion. RME is effective in expanding both maxillary and mandibular arches. Furthermore, SME is superior to RME in expanding molar region of maxillary arch, while similar with RME in mandibular arch expansion. However, we cannot compare their effectiveness in maxillary anterior region.

Integration accuracy of laser-scanned dental models into maxillofacial cone beam computed tomography images of different voxel sizes with different segmentation threshold settings

OBJECTIVE The aims were to examine the influence of cone beam computed tomography (CBCT)-scanned voxels and segmentation threshold settings on the accuracy of surface-based registration. STUDY DESIGN The samples were obtained from 10 adults. Each laser-scanned model was registered into a CBCT model by use of the iterative closest point algorithm. We calculated the shell-to-shell deviations between the 2 models and evaluated the results with color-mapping methods. The centroid coordinates were used to calculate the positional differences. Thresholds were expressed in relative Hounsfield units (RHU). RESULTS There was a statistically significant difference in shell-to-shell deviations between the 0.20-mm-voxel group and the 0.40-mm-voxel group (P < .001). There was a statistically significant difference in anteroposterior and superoinferior directions between the 200- and 700-RHU threshold models in 2 groups (P < .05). CONCLUSIONS The results indicated that the accuracy of the integration of laser-scanned dental models into CBCT images is higher with a high-RHU threshold setting in 0.20- and 0.40-mm voxel sizes.

Expression patterns of nociceptin in rats following experimental tooth movement

OBJECTIVES To determine the expression levels of nociceptin following experimental tooth movement. MATERIALS AND METHODS A total of 72 male Sprague-Dawley rats were divided into two groups: sham and experimental groups. For the experimental group, closed coil springs were used to mimic orthodontic force (80 g) between upper incisors and first molars, and the rats were killed at 0 hours, 4 hours, 12 hours, 1 day, 2 days, 5 days, 7 days, 10 days, and 14 days. All of these procedures were similar for the sham group, except for that no force was applied. The four rats killed at 0 hours without any intervention were used as the baseline control in each group. Trigeminal nucleus caudalis from both the ipsilateral and contralateral sides of force applications were obtained for immunostaining. RESULTS Nociceptin was expressed in both the ipsilateral and contralateral sides of each group. Its expression levels started to increase on day 2, peaked on day 7, and returned to baseline on day 10 in the experimental group, while expression levels started to decrease on day 1 and returned to baseline on day 10 in the sham group. Moreover, the expression levels were similar between the ipsilateral and contralateral sides in each group. CONCLUSION The expression levels of nociceptin were elevated following experimental tooth movement. The anesthetic agent used in this study (chloral hydrate) may have an antagonism with nociceptin. Due to bilateral innervation of anterior teeth and bilateral projection of nerve fibers, the expression levels of nociceptin were similar between ipsilateral and contralateral sides.