bluuebunny/crossref_metadata_2025_split huggingface dataset:
A survey of retention and retainer practices of orthodontists in Australia
Authors: Meade Maurice J. , Dreyer Craig W. 
Published: September 2021

Abstract

Objective
To survey retention and retainer practices of orthodontists in Australia.

Methods
A pilot-tested e-survey was distributed to 502 eligible members of the Australian Society of Orthodontists (ASO). The questions addressed participant background information, preferred retainer and retention practices, retainer characteristics and factors influencing retainer choice. Statistical analyses were performed using PASWH version 18.

Results
The response rate was 58%. Thermoplastic retainers (TRs) were the most commonly chosen retainer in the maxilla (39.4%) and bonded retainers (BRs) were most commonly chosen in the mandible (38.5%). An initial period of full-time wear of removable retainers (RRs) was prescribed by 37.7–48.3%. ‘Night/sleeping with reducing frequency over time’ was the most commonly prescribed part-time RR wear practice (28.1-33.5%).
Indefinite retainer wear was recommended by 85.3-87.4% of orthodontists. Indefinite retainer checks were carried out by 19.1-19.8% of orthodontists while 28.9-43.6% were ‘not happy’ for general dental practitioners (GDPs) to continue retention checks. Adjunctive retention practices were used by 25.6-72.8%. Pre-fabrication TR sheet thickness of 1.0 mm (68%) and polypropylene co-polymer/ethylene material type (55.8%) were most commonly used. Vacuum-forming was the preferred mode of TR fabrication by 48.4%. ‘Stainless steel single strand round’ was the most commonly used BR material type (33.4%). BR bonded to 12-22 (bonded to four teeth) was the most common BR design in the maxilla (48.8%) and 33-43 (bonded to six teeth) was most commonly chosen for the mandible (81.5%). Inadvertent tooth movement associated with BRs was observed by 62%. The orthodontist factor that most influenced retainer choice was the nature of the pretreatment malocclusion (88%).

Conclusion
Although there is agreement that retention is indefinite, orthodontic retention practices and retainer characteristics vary considerably between orthodontists in Australia. Greater communication between orthodontists and GDPs is required to effectively manage retention over the long term.
Evaluation of the posterior airway space following orthopaedic treatment of mandibular deficient Class II malocclusion – a pilot study
Authors: Costello Christopher J , Sambevski John , Cheng Lam L , Darendeliler M. Ali 
Published: September 2021

Abstract

Background
The use of Twin Block therapy is a well-accepted functional treatment option for the correction of a Class II malocclusion. In addition to skeletal and dental changes, its use may also promote changes in airway structure and dimension, including the size of the posterior airway space (PAS). This may be of importance in reducing the risk of developing obstructive sleep apnoea syndrome (OSAS).

Materials and methods
Sixteen (16) subjects (eight females and eight males) underwent treatment of a Class II division 1 malocclusion via the use of a Sydney Bonded Twin Block (SBTB) appliance followed by full fixed orthodontic therapy (FFOA). Pretreatment (T1), post-twin block (T2) and post-fixed appliance (T3) lateral cephalograms were taken and skeletal and soft tissue landmarks were hand traced. A pairwise comparison was used to assess whether there were any significant differences in the cephalometric variables between each phase of treatment (T1, T2, T3).

Results
The skeletal variables SNB and ANB revealed a significant change between T1-T2 (p < 0.01). The sagittal size of the nasopharynx (RPAS) also recorded a significant change between T1-T3 (p < 0.05). There was no significant change in the PAS at any stage of treatment. There was an average reduction in the ANB angle of 2° (p < 0.01) between T1-T3.

Conclusions
There was no significant change in the size of the PAS following SBTB treatment. However, an increase in RPAS was recorded following SBTB treatment which continued to improve during FFOA therapy.
Sexual dimorphism related to occlusal traits in Australian children
Authors: Ribeiro Daniela C , Dreyer Craig W. , Lähdesmäki Raija , Townsend Grant C 
Published: September 2021

Abstract

Background
The aim of the present study was to assess sexual dimorphism related to occlusal variables recorded from dental casts of Australian twins and to compare trends across primary (T1), mixed (T2) and permanent (T3) dentitions in the same individuals.

Methods
The sample comprised 22 males and 25 females selected at random from monozygotic pairs and 19 males and 19 females from dizygotic pairs. Overjet, overbite, midline deviation, midline diastema, primary and permanent molar relationship, and primary and permanent canine relationships were measured in millimetres using a digital calliper

Results
The mean values for overjet in males in the permanent dentition and for overbite in the mixed and permanent dentitions were significantly greater than those for females. The other occlusal traits showed no sexual dimorphism. Midline diastemata were most prevalent in the primary dentition while coincident midlines were most prevalent at all stages for both genders. In addition, a mesial step deciduous molar relationship was more prevalent on the right side and a flush terminal plane present on the left. Furthermore, a Class II permanent molar relationship was predominant in T1/T2, while a Class I relationship was most prevalent in the permanent dentition. Class II primary and permanent canine relationships were most common at all stages

Conclusions
Significant sexual dimorphism was found for overjet and overbite at several occlusal developmental stages but sexual dimorphism was not found for the other occlusal traits studied
The metal content of generic orthodontic brackets compared with proprietary brackets
Authors: Wishney Morgan , Savage Tom , Proschogo Nicholas , Petocz Peter , Darendeliler M. Ali 
Published: September 2021

Abstract

Background
With minimal manufacturer information, a variety of ‘generic’ orthodontic brackets are available online from overseas distributors. The present study investigated the metal composition of generic orthodontic brackets compared with two well-known ‘proprietary’ brands.

Materials and methods
Ranging in price from AU$2.99 to $65, five sets of different generic brackets were obtained directly from China via eBay (G1, G2…G5). Proprietary brackets were obtained from American Orthodontics (P1) and Rocky Mountain Orthodontics (P2). The 11, 12, 13 and 14 brackets from each set were liquefied in an acid solution and subjected to trace element analysis using inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES) with respect to nickel, chromium, iron, copper, molybdenum, manganese, cadmium, mercury, arsenic and lead. Statistical analysis investigated the compositional consistency within and between each brand.

Results
The composition of P1 and P2 agreed with the manufacturer’s data. The generic groups typically had low molybdenum and higher copper content and approximated either 17-4 or AISI304 stainless steels or a combination of both. No relationship between brand and consistency of manufacture could be identified. The cheapest bracket contained lead.

Conclusions
Generic and proprietary brackets showed differences in their metal composition that may have biocompatibility implications.
Effect of functional appliance therapy on the quality of life in skeletal Class II malocclusion
Authors: Imani Mohammad Moslem , Tabaii Elaheh Seyed , Jamshidi Saba , Arab Sepideh 
Published: September 2021

Abstract

Introduction
A Class II malocclusion is a common orthodontic problem that may affect social acceptance and the self-esteem of the patient. The aim of the present study was to evaluate the effect of functional appliance therapy on the oral health-related quality of life (OHRQOL) of patients presenting with a skeletal Class II malocclusion due to mandibular deficiency.

Methods
Forty-nine patients (11 to 14 years old) with a Class II malocclusion due to mandibular deficiency were included as the experimental group. A control group of 49 subjects was selected from school children without malocclusion. The Child Oral Impact on Daily Performance (Child-OIDP) index was administered, repeated and differences were evaluated following functional therapy using the Clark Twin Block appliance.

Results
At baseline, the most common oral impact on daily performance in the experimental group was emotional stability (35 patients, 71.4%) and smiling without shame (34 patients, 69.4%), which respectively decreased to 12.2% (six cases) and 20.4% (10 cases) after functional therapy. The mean (±SD) of the Child-OIDP Overall Impact score in the experimental group at baseline was 25.94 (±17.84), which significantly decreased to 2.77 (±2.09) after therapy (p < 0.001).

Conclusion
Functional therapy using the Clark Twin Block appliance had a significant effect in improving OHRQOL of children presenting with mandibular deficiency.
Treatment of identical twins with congenitally missing maxillary lateral incisors – a long-term follow-up
Authors: Wechsler Morris H. , Van Dong Phung 
Published: September 2021

Abstract
Congenitally missing upper lateral incisors can significantly alter the aesthetic appearance of a smile. The orthodontic challenge is to achieve acceptable facial aesthetics by restoring the dentition either by replacing the missing teeth or by substituting the canines for the lateral incisors. The present case report discusses the orthodontic treatment of two identical twin sisters with missing upper lateral incisors, in whom the spaces were reopened to accommodate prosthetic replacement. The rationale for this treatment alternative is discussed.
Dental age assessment in Caucasian subjects with third molar agenesis
Authors: Abu Alhaija Elham S. , Derbash Aftima A. , Al-Khateeb Susan N. 
Published: September 2021

Abstract

Background
Delayed dental development has been linked with tooth agenesis. Research aimed at dental age estimation in subjects with third molar agenesis has been minimal.

Objectives
To investigate the association between dental stage of development and third molar agenesis.

Materials and methods
A total of 700 orthopantomograms (OPTs) were obtained for this study. The age of the subjects ranged from 10 to 16 years (13.66 ± 1.50 years). The subjects were divided into two groups of which group 1 consisted of 350 patients (175 females and 175 males) with third molar agenesis and group 2 (control group) had all third molars present. The control group matched the study group for gender and chronological age (CA). Dental age (DA) was estimated from the OPTs using the Demirjian method for all included subjects.

Results
The mean CA and DA in the third molar agenesis group were 13.81 ± 1.60 years and 13.72 ± 1.65 years, respectively (p > 0.05). The mean CA and DA in the control group were 13.51 ± 1.38 years and 14.50 ± 1.12 years, respectively (t = 18.25, p > 0.000). CA-DA difference between the two groups was highly significant (t = 12.43, p > 0.000). Gender differences were not detected. Furthermore, no differences were noted in dental age compared with chronological age in cases of unilateral versus bilateral third molar agenesis or in one jaw versus two jaws (p > 0.05).

Conclusions
Dental development was delayed in subjects with third molar agenesis but the delay in dental age was not affected by the severity or site of agenesis.
Degradation and deformation of latex and non-latex orthodontic elastics
Authors: Oliveira Pedro Lima Emmerich , Matsumoto Mírian Aiko Nakane , Faria Gisele , Romano Fábio Lourenço 
Published: September 2021

Abstract

Background
Intermaxillary elastics are widely used in corrective orthodontic treatment particularly for the interdigitation of buccal segments and the correction of the midline. However, latex has been known to cause allergy, which may restrict elastic use. As alternative materials, non-latex elastics are available. However, clinicians must be aware of their mechanical properties, especially those of deformation and force degradation that affect these materials over time.

Objectives
The aim of this study was to compare force degradation and deformation of3/16” non-latex and latex elastics supplied by several manufacturers.

Materials and methods
Special acrylic plates were fabricated to incorporate orthodontic brackets to which elastics were attached and stretched to a distance of approximately 20 mm. The internal diameter and force magnitude of each elastic was measured at time intervals of 0, 24, 72 and 504 hours. The samples were stored in artificial saliva at room temperature during the entire experimental period.

Results
Latex elastics showed smaller and more uniform deformation than the non-latex elastics. The non-latex elastics showed greater degradation at all time intervals (p < 0.001). The Morelli brand delivered greater force than other brands for both the latex and non-latex elastics at all time intervals (p < 0.05). The G&H latex elastics showed greater force degradation in comparison with the other brands (p < 0.05). The evaluation of the Dentaurum and Orthopli non-latex elastics showed greater degradation (p < 0.05).

Conclusions
The non-latex elastics showed greater force degradation than the latex elastics. Of the latex elastics, G&H showed greater force degradation, and for the non-latex elastics, those made by Dentaurum and Orthopli degraded most.
The stability of occlusal plane rotation during orthognathic surgery
Authors: Bennett Samuel C. 
Published: September 2021

Abstract

Background
Considered rotation of the occlusal plane and the maxillomandibular complex during orthognathic surgery is an approach that enables optimisation of the functional and aesthetic outcomes of surgical-orthodontic treatment for the correction of a variety of dentofacial deformities.

Objectives
The objectives of this study are to: (1) retrospectively evaluate the stability of clockwise and anti-clockwise rotation of the occlusal plane during orthognathic surgery, and (2) compare the findings with the stability of orthognathic surgery in which no significant occlusal plane rotation occurs.

Aims and methods
Data were collected from a sample of 31 adult patients (22 females and nine males) treated by one orthodontist in private practice and at the University of Western Australia from 1992–2008. Patients received a Le Fort I osteotomy and BSSO to reposition the maxilla and mandible, respectively. The patients were separated into three groups defined by no occlusal plane rotation; clockwise occlusal plane rotation; or anti-clockwise occlusal plane rotation. Lateral cephalograms were taken at four time periods during treatment: T1 (pre-surgery), T2 (immediately post-surgery), T3 (six weeks post-surgery), and T4 (longest follow-up). The cephalograms were digitised and analysed using a customised cephalometric analysis (QuickCeph Studio, CA, USA) and landmarks were transferred via cranial base and maxillary superimpositions for each patient from T1 sequentially to T4.

Results
Clockwise rotation of the occlusal plane was highly stable one year following surgery and showed comparable results with cases treated without occlusal plane rotation. Anti-clockwise rotation of the occlusal plane was less stable and showed significant relapse of the occlusal plane angle towards the pre-surgical value during the post-surgical observation period.

Conclusion
Clockwise rotation of the occlusal plane during orthognathic surgery appears highly stable. Anti-clockwise occlusal plane rotation during orthognathic surgery appears less stable. Further studies are needed to evaluate the longer-term stability of clockwise and anti-clockwise rotation of the occlusal plane during surgical-orthodontic treatment.
Orofacial findings and serial extraction procedure in Noonan syndrome
Authors: Potrubacz Maciej Iancu , Chimenti Claudio , Marchione Laura , Tepedino Michele 
Published: September 2021

Abstract
The case of an 8-year-old female affected by Noonan syndrome is presented. The orofacial findings comprised a skeletal Class III malocclusion, transverse maxillary deficiency, a long face and severe tooth size-arch length discrepancy. The interceptive orthodontic approach focused on addressing the patient’s problems while keeping treatment as simple as possible. Management consisted of rapid maxillary expansion and serial extractions in the mandible. Treatment alternatives and results are discussed and a one-year follow-up is provided.
Comprehensive periodontal/orthodontic treatment of bimaxillary dentoalveolar protrusion caused by posterior bite collapse due to periodontal disease
Authors: Konno Masahiro , Iijima Masahiro , Kado Takashi , Furuichi Yasushi , Mizoguchi Itaru 
Published: September 2021

Abstract

Background
Increased mobility of teeth in adult patients with advanced periodontal disease causes posterior bite collapse, which is characterised by mesial inclination of the molars and vertical dimension loss, often resulting in bimaxillary dentoalveolar protrusion.

Aim
A case is reported of successful comprehensive periodontal/orthodontic treatment of a 51-year-old woman presenting with bimaxillary dentoalveolar protrusion accompanied by severe crowding in the mandibular arch and flaring of the maxillary anterior teeth as a result of posterior bite collapse due to periodontal disease.

Method
Miniplates and fixed appliances were used to upright the mandibular molars and create space for the retraction of the anterior teeth. Prior to orthodontic treatment, the patient underwent periodontal therapy to create a healthy oral environment. The treatment outcomes, including the periodontal condition, were stable 24 months after the conclusion of active orthodontic care.

Results and conclusion
The outcome demonstrates that anchorage control with miniplates is advantageous for the treatment of bimaxillary dentoalveolar protrusion and posterior bite collapse due to periodontal disease.
Multicentre evaluation of impacted and transmigrated canines: a retrospective study
Authors: Avsever Hakan , Gunduz Kaan , Akyol Mesut , Orhan Kaan 
Published: September 2021

Abstract

Objectives
The present multicentre study assessed the prevalence and patterns of impacted and transmigrated maxillary and mandibular canines in a Turkish subpopulation.

Methods
The study identified 1625 patients who had impacted teeth from a group of 10,700 patients (referred to three university hospitals between January 2014 and December 2015) and examined the accompanying records, panoramic and periapical radiographs, and cone-beam computed tomographic images (if available). An impacted canine was considered to be transmigrated when at least part of the tooth had crossed the midline.

Results
Out of 1625 patients, 163 (10.0%) had impacted canines (comprising a total of 170 affected teeth). Impacted canines were found in the maxilla in 114 patients (69.9%) and 49 patients (30.1%) showed mandibular canine impaction. Thirty-eight patients (2.3%) had transmigrated canines, of which twenty (52.6%) were located in the mandible, while 18 (47.4%) were found in the maxilla. No significant difference was evident between the genders, the site (right/left) and the impacted/transmigrated canines (p > 0.05). However, it was determined that canine impaction was significantly more frequent in the maxilla than in the mandible (p < 0.05). In addition, of the 38 patients presenting with transmigrated canines, eight (21.6%) had a history of alpha thalassemia.

Conclusions
Canine transmigration occurs in both the mandible and maxilla. The prevalence of impacted/transmigrated canines in the studied population was 10.0% and 2.3%, respectively. The mechanism of transmigration of maxillary canines remains unclear and requires further investigation. However, a possible correlation with genetic disorders (like alpha thalassemia) should not be overlooked.
Effects of mechanical vibration on root resorption in the rat molar induced by a heavy orthodontic force
Authors: Yeoh Ping Ping , Cheng Lam L. , Papadopoulou Alexandra K. , Darendeliler M. Ali 
Published: September 2021

Abstract

Background
Orthodontically-induced inflammatory root resorption (OIIRR) is an unwelcome side effect of orthodontic treatment. Mechanical vibration has been suggested as a preventative measure but evidence is limited. The aim of this study was to investigate whether whole body mechanical vibration has a positive influence on OIIRR.

Material and methods
Thirty-six 10-week-old Wistar rats were divided into three groups, which received either 30 Hz vibration, 60 Hz vibration or no vibration to serve as a control group. A heavy mesial force of 100 g was applied to the left maxillary first molar using nickel-titanium closed-coil springs. The right maxillary first molar served as an internal control. The vibration groups received 30 Hz or 60 Hz of whole body vibration for 10 minutes per day for 14 days. A volumetric analysis of the extent of root resorption on the mesial-buccal root of the first maxillary molar was examined using micro-computed tomography.

Results
When compared with the control group, the animals that received 30 Hz (p = 0.21) and 60 Hz (p = 0.16) of mechanical vibration did not show a statistically significant reduction in OIIRR. The results did not show a statistically significant difference in the extent of OIIRR between 30 Hz and 60 Hz vibration groups (p = 0.78).

Conclusion
Mechanical vibration at 30 Hz and 60 Hz, when applied in an experimental model of whole body vibration, showed no significant effect on either physiological root resorption or OIIRR in rat molars loaded by a heavy orthodontic force.
Alveolar bone height and thickness assessed by CBCT
Authors: García-Sanz Verónica , Paredes-Gallardo Vanessa , Montiel-Company José María , Gandía-Franco José Luis , Bellot-Arcís Carlos 
Published: September 2021

Abstract

Objectives
To seek information regarding the relationship between the quantity of alveolar bone and the angle and sagittal position of the incisors. This was to be further determined in relation to the basal bones and facial pattern with the aim of establishing a predictive model based on the study of a lateral cephalogram.

Methods
The distance from the cemento-enamel junction to the labial alveolar crest and the bone thickness half-way along the root of the most prominent upper and lower incisor were measured in a sample of 100 cone beam computed tomography (CBCT) scans of patients aged between 15 and 34 years. Lateral cephalograms of the patients were extracted from the scans and used to measure the buccolingual angle and antero-posterior position of the incisors in addition to the facial pattern of each patient.

Results
A correlation was found between bone thickness around the upper incisor and the variables of the incisal angle and its sagittal position. The inclination of the lower incisor (IMPA) was related to cortical bone thickness. The cemento-enamel junction to alveolar crest measurement (bone height) was related to the antero-posterior position of the lower incisor in men. The facial pattern was unrelated to any of the variables.

Conclusions
The angle and sagittal position of the upper and lower incisors were associated with alveolar bone thickness in men. Only the antero-posterior position of the lower incisor was related to its alveolar bone height. In women, only the angle of the lower incisor was associated with bone thickness.