bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of non-extraction orthodontic treatment on the vertical dimension: a comparison of a dolichofacial and a mesofacial group
Authors: Lin Chia-Hung , Short Lesley L. , Banting David W. 
Published: August 2023

Abstract

Objective: The decision regarding extraction or non-extraction orthodontic treatment for patients with different skeletal facial patterns is more commonly based on traditional concepts rather than scientific facts. The present study aimed to investigate whether dolichofacial patients responded differently compared with mesofacial patients to non-extraction orthodontic treatment with respect to vertical changes in facial height.

Methods: Twenty-eight dolichofacial patients and 29 mesofacial patients who underwent non-extraction orthodontic treatment were selected. All patients commenced treatment prior to 15 years of age and had a mean age of 12.3 years for the dolichofacial group and 12.6 years for the mesofacial group. Serial lateral cephalometric radiographs were traced by hand on acetate paper and digitised using the Rocky Mountain Orthodontics JOE 32 programme. Statistical analysis examined the recorded changes in facial axis angle, facial angle, menton-to-ANS distance and facial convexity.

Results: An increase in menton-to-ANS distance and facial angle and a decrease in facial convexity were observed in both groups to a similar extent. Interestingly, the facial axis of both groups remained constant throughout treatment and up to two years post-treatment. Both groups showed slightly increased facial axis angle beyond the original value at two years post-treatment. No statistically significant difference between the two groups was observed in the changes of any of the variables over time.

Conclusion: The results countered the traditional concept that dolichofacial patients would have an increased facial height after being subjected to non-extraction orthodontic mechanics. It appeared that long-term vertical height of the face was more dependent on genetics rather than environmental influences.
The effect of changing crosshead speed on the shear bond strength of orthodontic bonding adhesive
Authors: Shooter Kerry J. , Griffin Mark P. , Kerr Brett 
Published: August 2023

Abstract

Objective: To examine the influence of different crosshead speeds on the in vitro shear bond strength and adhesive remnant index scores for the same orthodontic adhesive.

Materials and methods: One hundred human molars were randomly allocated to four groups. Brackets (.022 inch Victory series, 3M, Monrovia, CA, USA) were bonded with Ortho Solo primer (Ormco, Glendora, CA, USA) and Enlight (Ormco, Glendora, CA, USA) adhesive paste to their buccal surfaces. The brackets were debonded with a universal testing machine (Instron, Canton, MA, USA) with each group subjected to a different crosshead speed of 0.5 mm/min, 1.0 mm/min, 2.0 mm/min and 5.0 mm/minute. Shear bond strength (SBS) was measured and enamel surfaces were examined to determine the adhesive remnant index (ARI) score.

Results: No significant differences were found between the mean SBS or ARI score for any of the groups.

Conclusions: Studies using different crosshead speeds when testing identical adhesives may be used to compare the SBS of other orthodontic adhesives, provided the testing protocols are similar.
The effects of face mask therapy with and without rapid maxillary expansion in adolescent patients
Authors: Yavuz İbrahim , Halıcıoğlu Koray , Ceylan İsmail , Dağsuyu İlhan Metin , Erdem Abdulvahit 
Published: August 2023

Abstract

Objective: To examine the effects of face mask therapy with and without associated rapid maxillary expansion (RME) in adolescent patients presenting with skeletal Class III malocclusion characterised by maxillary retrognathism.

Methods: Case records consisting of lateral cephalograms and hand-wrist films of 43 patients with hypoplastic maxillary Class III malocclusions treated using a face mask with and without an RME were analysed. The patients were divided into two groups; Group A (N = 27) were treated with a face mask coupled with rapid maxillary expansion and patients in Group B (N = 16) were treated with a face mask appliance only. Ten cephalometric linear and 9 angular variables were measured to assess the dentofacial changes. Within group and between groups comparisons were determined by a paired t-test and Student’s t-test, respectively.

Results: Forward displacement of the maxilla and a clockwise rotation of the mandible occurred in both groups. The maxillarymandibular relationship improved and soft-tissue changes resulted in a more convex profile. The maxillary incisors moved forward only in Group B subjects but the mandibular incisors moved backward in both groups.

Conclusions: Face mask therapy with and without an associated RME improved skeletal Class III malocclusion by a combination of skeletal and dental changes. These results suggested that the use of an RME should be based on clinical criteria rather than assisting the Class III correction.
The force-distance properties of attracting magnetic attachments for tooth movement in combination with clear sequential aligners
Authors: Phelan Angie , Petocz Peter , Walsh William , Ali Darendeliler M. 
Published: August 2023

Abstract

Background: The demand for clear sequential aligner therapy has increased dramatically in recent years. An improved system utilising small neodymium-iron-boron (NdFeB) magnetic attachments has been proposed to enhance appliance capabilities.

Aim: The aim of the investigation was to analyse the force system diagrams produced by small attracting NdFeB magnets to determine, 1) whether the force levels were sufficient to induce tooth movement, 2) the effect of magnet morphology on force characteristics and, 3) the most appropriate magnet dimensions that could be utilised for this application.

Methods: Twenty-nine NdFeB rectangular magnets of varying dimensions were tested. A Mach-1 universal testing machine (Biosyntech Inc, Quebec, Canada) was used to measure the attractive force of pairs of magnets. Measurements commenced with a magnetic pair in contact and subsequently vertically separated a distance of 10 mm at a speed of 12 mm/minute. For all magnetic configurations four repeat measurements were performed on five magnetic pairs of the same size.

Results: The force-distance diagrams for all magnet configurations demonstrated a dramatic decrease in force with increasing magnet separation. Rather than a suggested inverse square law, the experimental data followed an inverse fourth law when an offset determined by a regression analysis was applied to the distance. For the majority of magnets, insignificant forces were attained beyond 2 mm of separation. Magnets with large pole face areas and longer magnetic axes provided the greatest force.

Conclusions: A select range of magnet configurations exhibited suitable and reliable attractive forces and therefore could be advocated for prescribed clinical application.
A pharmacodynamic investigation into the efficacy of osteoprotegerin during aseptic inflammation
Authors: Curl Linda , Barker Christopher , Dreyer Craig , Sampson Wayne 
Published: August 2023

Abstract

Background: Osteoprotegerin (OPG), as an osteoclast antagonist, limits mineralised tissue resorption under physiological conditions. Previous work investigating OPG in a rat periodontal ligament (PDL) ankylosis model found no inhibitory effect on osteoclasts when OPG was administered at a dosage of 2.5mg/kg.1,2

Aims: The object of this study was to determine whether dosages higher than 2.5 mg/kg of OPG were required to limit osteoclastic activity in an aseptic inflammatory model in rats.

Materials and methods: Dry ice was applied for 15 minutes to the upper right first molar crown of eighteen, 8-week-old, male Sprague-Dawley rats. Three groups of 3 were injected with OPG at dosages of 2.5, 5.0 and 7.5 mg/kg of body weight immediately following the thermal insult. After 7 days, the rats were sacrificed and each maxilla processed for histological examination and stained for osteoclastic activity using tartrate-resistant acid phosphatase (TRAP). Osteoclast population numbers were estimated via light microscopy and results were analysed using a comparative mixed model statistical analysis.

Results: Results showed OPG inhibited osteoclastic activity in a dose-dependent manner. From 2.5 mg/kg to 7.5 mg/kg, osteoclast populations were linearly reduced by 39.8% (p < 0.05). OPG did not appear to affect the inflammatory process and had varied efficacy in different regions of individual teeth.

Conclusion: Although osteoclastic activity reduced, it was not completely eliminated, perhaps because dosages were still inadequate, or additional factors might influence OPG and osteoclast activation in the aseptic inflammatory model.
Morphological effects of mesenchymal stem cells and pulsed ultrasound on condylar growth in rats: a pilot study
Authors: Oyonarte Rodrigo , Becerra Daniela , Díaz-Zúñiga Jaime , Rojas Victor , Carrion Flavio 
Published: August 2023

Abstract

Aim: The aim of this study was to assess and describe the morphological effects of an intra-articular injection of Mesenchymal Stem Cells (MSCs) and/or Low Intensity Pulsed Ultrasound (LIPUS) stimulation on the mandibular condyles of growing rats, using cone beam computed tomography (CBCT) and histology.

Methods: Twenty-six young (23-day-old) rats were divided into 5 groups identified as LIPUS-stimulated (20 minutes daily using 50 mW/cm2, 1MHz, 0.2 millisecond pulses), MSCs injected (1 x 105 cells/kg), LIPUS + MSCs, medium injected, and untreated controls. All treatments were performed in the left temporomandibular joint of each rat (TMJs). At day 21, CBCTs were obtained for cephalometric analysis and 3D reconstructions. After animal sacrifice, left and right TMJ sections were histologically prepared and examined. The Wilcoxon sign rank test and the Kruskal-Wallis 2 test were applied for statistical comparison.

Results: Imaging results showed that left condyles were wider in all LIPUS-treated groups (p < 0.05), while the LIPUS-only group had a greater left sagittal condylar length. LIPUS-treated groups displayed a lower midline shift to the right (p < 0.02). No significant differences were observed in the MSC group. Bone marrow morphology and vascularity differed between the groups as LIPUS-treated groups exhibited increased vascularity in the erosive cartilage zone.

Conclusion: It was established that LIPUS and MSC application to the TMJ region of growing rats favoured transverse condylar growth, while LIPUS application alone may enhance sagittal condylar development. The MSC injection model had little effect on sagittal condylar growth.
On the augmented reproducibility in measurements on 3D orthodontic digital dental models and the definition of feature points
Authors: Jacquet Wolfgang , Nyssen Edgard , Ibel Gabriele , Vannet Bart Vande 
Published: August 2023

Abstract

Objective: The objective of this study was to explore digital measurement methodology on 3-dimensional (3D) dental models. Standardised manipulation and practices have lead to reliable measurements on plaster casts. Identifying landmarks on digital models or digitised plaster casts is fundamentally different from actual measurements. Three-dimensional models are represented on flat screens and landmarks are individually indentified. A procedure is proposed that resolves the deficiencies associated with a 2-dimensional (2D) display through an appropriate model representation and through local optimisation.

Methods: Fifteen models (OrthoProof) were exported to a locally developed 3D point indication software package, in which two measurement approaches were implemented involving standard projection with and without local search. Nine linear measurements were obtained from plaster casts and digital models. Statistical analysis included correlation and Friedman’s non-parametric analysis of variance (ANOVA).

Results: For five out of nine linear measurements, digital indications yielded results significantly different from manual measurements (p = 0.05). Local search considerably improved measurement accuracy and reliability.

Conclusions: Measurements on plaster casts can differ significantly from those obtained through digital identification methods. These differences prove to be clinically relevant. Standardisation and optimisation resulted in improved and extremely reliable digital measurements.
Evaluation of dental and basal arch forms using cone-beam CT and 3D virtual models of normal occlusion
Authors: Bayome Mohamed , Park Jae Hyun , Han Seong Ho , Baek Seung-Hak , Sameshima Glenn T. , Kook Yoon-Ah 
Published: August 2023

Abstract

Objectives: To evaluate the relationship between the mandibular dental and basal arches using CBCT, and to assess the correlation between basal arch dimensions derived from CBCT and 3-dimensional (3D) virtual models in a cohort sample exhibiting normal occlusions.

Methods: The facial axis (FA) and root centre (RC) points of mandibular teeth were identified on 32 CBCT images. FA and WALA points were digitised on 3D models of 28 mandibular casts from the same sample. The relationships between dental and basal arch dimensions, and between the two basal depth dimensions derived from RC and WALA points were statistically assessed by Pearson’s correlation.

Results: Strong correlations were found between dental and basal intercanine and intermolar arch widths. Also, the basal intercanine width showed a moderate correlation with dental intermolar width and depth. The basal intercanine and intermolar widths measured on 3D models showed moderate correlations with those measurements on CBCT, whereas the basal canine and molar depths showed no correlations.

Conclusions: The dental and basal anterior and posterior arch widths were strongly correlated in normal occlusion. No correlations were found between the arch depths measured from WALA points and RC points. Hence, RC points may represent more useable landmarks compared to WALA points in the evaluation of basal arch forms. It is recommended that the relationship between the dental and basal arches is evaluated during treatment planning in order to improve arch co-ordination.
Occlusal variation in the Zuni: a pre-contact North American population
Authors: McKeever Aidan , Sutcliffe Paul 
Published: August 2023

Abstract

Background: Reports of occlusal variation in ancient populations consistently show a low prevalence of malocclusion coupled with heavy attritive wear.

Materials and methods: The dentitions of 28 individual remains from a pre-contact native North American population were examined and the extent and nature of occlusal variation recorded.

Results: The prevalence of malocclusion was low (mean IOTN = 2.14) and where crowding existed, was limited to intra-arch variability as opposed to inter-arch discrepancies. Increased overbites, overjets and other classical features of Class II malocclusions were almost entirely absent. These findings suggest that the ideal mutually protected Class I occlusion occurs only as a transient juvenile arrangement in nature, where, due to rapid attrition following establishment of the occlusion, there is an increasing tendency towards mild Class III, edge-to-edge incisor and buccal segment relationships.

Conclusion: Whilst of limited therapeutic benefit, an understanding of the anthropology of malocclusion provides an insightful perspective, and suggests that function may be of more importance than heredity in its aetiology. It is suggested that future occlusal studies in ancestral populations would benefit from the use of a standard methodology.
An evaluation of condylar and ramal vertical asymmetry in adolescents with unilateral and bilateral posterior crossbite using cone beam computed tomography (CBCT)
Authors: Halicioglu Koray , Celikoglu Mevlut , Yavuz Ibrahim , Sekerci Ahmet Ercan , Buyuk Suleyman Kutalmis 
Published: August 2023

Abstract

Aims: The primary purpose was to evaluate condylar and ramal vertical asymmetry in adolescent patients displaying unilateral posterior (UCB) and bilateral posterior crossbite (BCB) malocclusions. A secondary aim was to compare the findings with a matched control group exhibiting normal occlusion (CG) using cone beam computed tomography (CBCT).

Material and methods: The study groups consisted of (1) 30 patients (Mean age: 14.49 ± 1.91years) with a UCB, (2) 29 patients (Mean age: 14.57 ± 1.84 years) with a BCB, and (3) 36 patients (Mean age: 14.24 ± 2.42 years) as a matched control group (CG). Condylar, ramal, condylar-plus-ramal height and index measurements were performed using CBCT images following the method of Habets et al. A paired t-test was performed for side comparison in each group. One-way ANOVA (Analysis of Variance) was used to determine statistically-significant differences between the groups for asymmetry index measurements and Tukey’s HSD test was employed for individual group differences.

Results: There was no statistically significant difference in condylar height (CH), ramal height (RH), and condylar plus ramal height (CH + RH) measurements between the right and left sides of the UCB group and CG, except for the RH in the BCB group (p = 0.045). Tukey’s HSD test showed that the ramal asymmetry index (RAI) and the condylar plus the ramal asymmetry index (CRAI) were statistically significantly different between the UCB and BCB groups (p = 0.035 and p = 0.015, respectively).

Conclusions: Although the condylar asymmetry index (CAI) values were found to be high in the groups of UCB (13.84 ± 11.33), BCB (9.38 ± 8.56), and CG (10.58 ± 9.48), the comparisons amongst the groups were not statistically significant. The asymmetry between the UCB and BCB groups was observed for RAI and CRAI values, rather than CAI values.
A qualitative investigation of RANKL, RANK and OPG in a rat model of transient ankylosis
Authors: Curl Linda , Tan Chien Wei , Dreyer Craig W. , Sampson Wayne 
Published: August 2023

Abstract

Introduction: Previous studies have found ankylosis occurs as a part of the inflammatory process of aseptic root resorption initiated in a rat model.1 The physiologic mechanisms behind the development of dentoalveolar ankylosis and healing response are still unclear. While receptor activator of nuclear factor-κβ ligand (RANKL), receptor activator of nuclear factor-κβ (RANK) and osteoprotegerin (OPG) have gained momentum in the understanding of resorption, no study to date has investigated their role in dentoalveolar ankylosis.

Aims: The aims of this study were to investigate if, and when, ankylosis occurred in the rat PDL, whether the resolution of ankylosis occurred with time and, finally, to observe the expression of RANKL, RANK and OPG during the ankylotic process.

Materials and methods: Dry ice was applied for 20 minutes to the upper right first molar crown of 15 eight-week-old, male Sprague-Dawley rats. An additional three rats served as untreated external controls. Groups of three rats were sacrificed after the thermal insult on day 0, 4, 7, 14 and 28 respectively. Each maxilla was dissected out and processed for histological examination and RANKL, OPG and RANK immunohistochemistry.

Results: By the use of light microscopy and H&E staining, no ankylosis was detected in the external control group and the experimental groups at days 0 and 4. On day 7, disruption within the periodontal ligament was observed in the interradicular region and the initial signs of ankylosis were seen in the form of finger-like projections extending from the alveolar bone towards the cementum. Fourteen days after the thermal insult, all animals exhibited extensive ankylosis that spanned the entire interradicular periodontal space. At 28 days, the development of ankylosis appeared to have ceased and repair was observed, together with an intact periodontal ligament in all but one rat. Positive staining results were obtained with RANKL, RANK and OPG antibodies. The expressions of RANKL, RANK and OPG were similar in the external control group, 0-, 4-, and 28-day experimental groups. In the 7- and 14-day experimental groups, RANKL, RANK and OPG were expressed in the blood vessels within the ankylotic regions.

Conclusions: During the development of ankylosis and its resolution, it was concluded from their simultaneous presence that there is a complex interaction between RANKL, RANK and OPG that requires further investigation.
Accelerating orthodontic tooth movement with the aid of periodontal surgery – the practitioner viewpoint
Authors: Kim Berna , Dreyer Craig W. , Sampson Wayne 
Published: August 2023

Abstract

Introduction: There has been a revival of interest in the acceleration of orthodontic tooth movement (OTM) by inducing injury to dentoalveolar cortical bone. Termed corticotomy, the procedure offers an advantage to adult patients whose bone metabolism is such that any reduction in treatment time would be welcomed. The procedure has been refined for over 100 years and recent research indicates treatment duration may be reduced often by as much as a third, but it is not clear how widely the method is applied in practice. For the procedure to be successful, careful interdisciplinary management by orthodontists and periodontists is required. However, information regarding the attitude and knowledge of practitioners and the frequency of the procedure performed in Australia and New Zealand is lacking.

Methods: A questionnaire was formulated and tested in a pilot study on postgraduate orthodontic and periodontic students at The University of Adelaide. As a consequence of the responses, the wording of several questions was clarified and the sequence modified to produce the final format. Separate questionnaires were developed for specialist orthodontists and periodontists in keeping with their different backgrounds and were distributed at two relevant conferences.

Results and conclusions: The number of practitioners who had been involved with at least one corticotomy per annum was low for orthodontists (12%) and periodontists (18%). The majority of those surveyed believed that more research was required on corticotomy-facilitated OTM and would not recommend the procedure to patients without greater investigation of the technique. More than half of the sampled orthodontists indicated that they would never recommend corticotomy-facilitated orthodontics to their patients. The minority who were willing to recommend the procedure would limit involvement to adult patients, the management of ankylosed teeth, impacted canines and patients susceptible to root resorption. Over 90% of the sampled periodontists believed that there were adverse side effects.
Modulatory Role of Galectin-1 in Ulcerative Colitis with Comorbid Metabolic Syndrome
Authors: Corovic Kemal , Stojanovic Bojan , Petrovic Andjela , Stanisavljevic Isidora , Maric Veljko , Zdravkovic Natasa , Jovanovic Marina 
Published: August 2023

Abstract
Metabolic syndrome (MetS) and ulcerative colitis (UC) are widespread health conditions characterized by chronic, low-grade inflammation. Galectin-1 (Gal-1), an immunomodulatory peptide mainly secreted from adipose tissue, could potentially play a crucial role in mitigating these conditions. This cross-sectional study explores the involvement of Gal-1 in MetS and UC within a cohort of 75 patients, newly diagnosed with UC. The MetS subgroup displayed increased fecal Gal-1 levels compared to those without MetS. Furthermore, Gal-1 showed predominance over pro-inflammatory cytokines, including TNF-α, IL-6, and IL-17, in these subjects. These findings emphasize the potential involvement of Gal-1 in the pathophysiology of UC and MetS, presenting it as a promising diagnostic biomarker and therapeutic target for these conditions.