In Vitro Comparison of Different Invisalign® and 3Shape® Attachment Shapes to Control Premolar Rotation

Aim: To evaluate in vitro the differences of various Invisalign® attachments in their effectiveness during derotation of an upper second premolar in terms of forces and moments created and compare them to the 3Shape® box attachment as well as to no attachment at all.

Materials and Methods: A Force System Identification (FSI) machine, comprising two load sensors, was used in this study. Sensor 1 was connected to the test tooth (i.e. upper second premolar) carrying a different attachment design, and the fixed sensor (Sensor 2) was connected to the base model. Once the corresponding aligner was passively seated on the teeth, 12 different setups (i.e. 11 different attachments and one setup with no attachment at all) were tested by rotating the test tooth 4.5° mesially and 4.5° distally, in increments of 0.45°.

Results: The vertical rectangular attachments were able to generate the highest derotational moment on both mesial and distal rotations but also received the most side effects (intrusive force, torque, and tipping). The no-attachment setup performed least favorably in terms of derotational ability but exhibited the least side effects. In the y-axis, all attachments received a buccal root torque with a lingual force during disto-rotation and a lingual root torque with a buccal force during mesio-rotation.

Conclusion: Attachments are necessary for derotating an upper second premolar. An aligner incremental change of more than 1° derotation can generate high moments. The vertical rectangular attachments perform best in derotations; however, they exhibit the most side effects. Finally, despite presenting the least side effects, derotation of a premolar with no attachment is not as efficient.

Three-dimensional analysis of craniofacial morphology in patients with pycnodysostosis

OBJECTIVE

To perform a 3D cephalometric analysis of the craniofacial characteristics of patients with pycnodysostosis and compare this with a matched control group.

SETTING AND SAMPLE POPULATION

This cross-sectional descriptive study assessed eight CBCTs obtained in patients with pycnodysostosis (4 males, 4 females, mean age: 31.8 years).

MATERIALS AND METHODS

Eight Danish patients with pycnodysostosis were seen at the University's Orthodontic Clinic. All CBCTs were analysed using the Mimics 21.0 software (Materialise®, Belgium) and compared with a control group (6 males, 8 females, mean age: 33.6 years).

RESULTS

Interclass correlation coefficient showed excellent intra-rater reliability (> 0.93). All measurements in the 3D cephalometric analysis revealed statistical significance (P < .05) when compared with controls. Patients with pycnodysostosis generally had significantly smaller maxilla in the transverse (P < .001), sagittal (P < .002) and vertical (P < .001) dimensions. Their mandibles were also smaller vertically (P < .001) and in length (P < .001). Gonial angle was significantly larger than controls (P < .001), while mandibular volumes were considerably smaller (P < .001).

CONCLUSION

Patients with pycnodysostosis have significantly smaller jaws in the vertical, sagittal and transverse dimensions compared with controls. Furthermore, the gonial angle was significantly larger, while the volume of the mandible was significantly smaller.

Obstructive Sleep Apnoea in pycnodysostosis; a three-dimensional upper airway analysis

AIM

To assess the upper airway (UA) morphology in patients with pycnodysostosis with a 3D analysis, compare results with normative data and investigate correlation of the total volume (TV) to other UA morphology variables.

MATERIALS AND METHODS

Cone beam computed tomography (CBCT) images of eight Danish patients with pycnodysostosis (4 males, 4 females with a mean age of 31.8 years, SD:16.3 years), were analysed using Mimics® (Materialise®, Belgium) and compared with a sex- and age-matched control group (6 males, 8 females with a mean age of 33.6 years, SD:18.6 years).

RESULTS

The distance from the tip of the epiglottis (E) to the Frankfurt horizontal plane (Fp) was significantly shorter in the pycnodysostosis group (p < 0.042). Regarding the cross-sectional measurements, at the "maximum constriction" (p < 0.005), the "upper airway limit" (p < 0.001) and the "lower airway limit" (p < 0.035) cross-sections were significantly smaller in the pycnodysostosis group. The volumes "nasopharynx" (p < 0.002) and "total airway" (TV) (p < 0.01) were also significantly smaller.

CONCLUSION

Patients with pycnodysostosis have a reduced total airway as well as nasopharyngeal volume compared with matched controls. Additionally, they have a reduced cross-sectional area in the upper and lower borders of the UA, and the area of maximum constriction is also reduced. These factors might explain the high prevalence of obstructive sleep apnoea in pycnodysostosis. TV is positively correlated to total length and cross-sections at all levels including the maximum constriction area as well as the anteroposterior dimension at the upper and lower airway borders.

Pycnodysostosis: Characteristics of teeth, mouth and jaws

OBJECTIVES

To describe the clinical and radiographic oro-dental characteristics of patients with pycnodysostosis (PDO).

MATERIALS & METHODS

A short interview and clinical examination of seven patients with PDO were performed as well as assessment of the temporomandibular joints and masticatory muscles using the diagnostic criteria for temporomandibular disorders, DC-TMD form. A full set of records were taken including photos and intraoral scan. Finally, existing cone beam computed tomography (CBCT) images and radiographs were also studied.

RESULTS

All patients presented with bimaxillary micrognathia, five had a convex profile, and two had a straight profile. In addition, posterior open bite, Angle Class III molar relation with accompanying anterior crossbite and a grooved median palate were common findings. No patient showed symptoms of temporomandibular disorder (TMD) apart from some clicking. Finally, the main radiographic findings were the obtuse mandibular angle, the frontal bossing, the elongation of the coronoid/condylar process and the presence of hypercementosis with obliterated pulp chambers.

CONCLUSION

The examined patients with PDO were characterized by dental crowding, malocclusion (anterior crossbite, posterior open bite), hypercementosis, obliterated pulp chambers and deviations in mandibular morphology. In conclusion, patients with PDO have a specific need for dental and orthodontic monitoring with focus on crowding and posterior open bite. The patients will benefit from a long-term orthodontic plan including extractions.

Quality assessment of online information on orthodontic Web sites in the United States

INTRODUCTION

The objective of this study was to assess the quality of online information on orthodontic treatment provided by orthodontic Web sites in the United States and investigate their claims.

METHODS

Three hundred and one American orthodontic Web sites were identified after an advanced Google search. Data collection included: the location of the clinic, treatment options offered, quality-of-information assessment using the DISCERN tool, and finally, claims when promoting 1 treatment option against another, as well as the presence of information on relapse risk and retention needs.

RESULTS

All Web sites belonged to private clinics, with more than half (60.5%) in a single location. Invisalign (Align Technology, Santa Clara, Calif) was the most commonly promoted treatment option (94%), followed by the full fixed appliance (FFA) (92%). The mean DISCERN total score was poor (36.78 out of 80.00), whereas the mean reliability (questions 1-8) and quality-of-information (questions 9-15) scores were 17.06 out of 40.00 and 16.85 out of 35.00, respectively. Almost one-third (28%) of the Web sites compared aligners to FFA, whereas 25% claimed that aligners are less painful than FFA, faster than FFA (14%), or give better results than FFA (1%). Almost half of the Web sites (47%) failed to display information on relapse risk and retention needs after orthodontic treatment (41%). The Web sites that displayed such info had higher DISCERN total scores (P <0.001).

CONCLUSIONS

Invisalign seems to be the treatment modality most commonly mentioned online. According to DISCERN, U.S. orthodontic Web sites display poor or fair quality information. On many Web sites, aligner treatment was compared with FFA, with some stating that aligners cause less pain than FFA or are more efficient/faster than FFA. Moreover, almost half of the American orthodontic Web sites failed to display information on the relapse risk or retention need. Display of such information can be an indicator of better-quality Web sites. There is ample room for improvement in the online information American orthodontists provide to potential patients.

Patient safety in orthodontic care: a scoping literature review with proposal for terminology and future research agenda

BACKGROUND

Knowledge about patient safety in orthodontics is scarce. Lack of standardisation and a common terminology hinders research and limits our understanding of the discipline. This study aims to 1) summarise current knowledge about patient safety incidents (PSI) in orthodontic care by conducting a systematic literature search, 2) propose a new standardisation of PSI terminology and 3) propose a future research agenda on patient safety in the field of orthodontics.

METHODS

A systematic literature search was performed in the main online sources of PubMed, Web of Science, Scopus and OpenGrey from their inception to 1 July 2023. Inclusion criteria were based on the World Health Organization´s (WHO) research cycle on patient safety. Studies providing information about the cycle's steps related to orthodontics were included. Study selection and data extraction were performed by two of the authors.

RESULTS

A total of 3,923 articles were retrieved. After review of titles and abstracts, 41 articles were selected for full-text review and 25 articles were eligible for inclusion. Seven provided information on the WHO's research cycle step 1 ("measuring harm"), twenty-one on "understanding causes" (step 2) and twelve on "identifying solutions" (step 3). No study provided information on Steps 4 and 5 ("evaluating impact" or "translating evidence into safer care").

CONCLUSION

Current evidence on patient safety in orthodontics is scarce due to a lack of standardised reporting and probably also under-reporting of PSIs. Current literature on orthodontic patient safety deals primarily with "measuring harms" and "understanding causes of patient safety", whereas less attention has been devoted to initiatives "identifying solutions", "evaluating impact" and "translating evidence into safer care". The present project holds a proposal for a new categorisation, terminology and future research agenda that may serve as a framework to support future research and clinical initiatives to improve patient safety in orthodontic care.

REGISTRATION

PROSPERO (CRD42022371982).

Lessons learnt on patient safety in dentistry through a 5-year nationwide database study on iatrogenic harm

Safe delivery of care is a priority in dentistry, while basic epidemiological knowledge of patient safety incidents is still lacking. The objectives of this study were to (1) classify patient safety incidents related to primary dental care in Denmark in the period 2016-2020 and study the distribution of different types of dental treatment categories where harm occurred, (2) clarify treatment categories leading to "nerve injury" and "tooth loss" and (3) assess the financial cost of patient-harm claims. Data from the Danish Dental Compensation Act (DDCA) database was retrieved from all filed cases from 1st January 2016 until 31st December 2020 pertaining to: (1) The reason why the patient applied for treatment-related harm compensation, (2) the event that led to the alleged harm (treatment category), (3) the type of patient-harm, and (4) the financial cost of all harm compensations. A total of 9069 claims were retrieved, of which 5079 (56%) were found eligible for compensation. The three most frequent categories leading to compensation were "Root canal treatment and post preparation"(n = 2461, 48% of all approved claims), "lack of timely diagnosis and initiation of treatment" (n = 905, 18%) and "surgery" (n = 878, 17%). Damage to the root of the tooth accounted for more than half of all approved claims (54.36%), which was most frequently a result of either parietal perforation during endodontic treatment (18.54%) or instrument fracture (18.89%). Nerve injury accounted for 16.81% of the approved claims. Total cost of all compensation payments was €16,309,310, 41.1% of which was related to surgery (€6,707,430) and 20.4% (€3,322,927) to endodontic treatment. This comprehensive analysis documents that harm permeates all aspects of dentistry, especially in endodontics and surgery. Neglect or diagnostic delays contribute to 18% of claims, indicating that harm does not solely result from direct treatment. Treatment harm inflicts considerable societal costs.