Effects of invisible orthodontic retainers on masticatory muscles activity during sleep: a controlled trial
Prog Orthod. 2018 Jul 23;19(1):24. doi: 10.1186/s40510-018-0228-y.
ABSTRACT
BACKGROUND: This study aims to evaluate if invisible orthodontic retainers can affect sleep-time masticatory muscle activity (sMMA) over a short-term period in healthy individuals.
METHODS: Nineteen (N = 19) healthy subjects underwent an in-home evaluation with a portable device for electromyographic (EMG) assessment. The study protocol provided two baseline recording nights, a night off, and then two additional nights with passive customized orthodontic retainers in situ. For each recording night, the sleep bruxism (SB) index (i.e., average number of SB events/hour) and the overall number of masseter muscle contractions were assessed. Comparison between values gathered over the four recording nights was made with a parametric test, based on the null hypothesis that there was no difference between wearing or not wearing the retainers as far as the sMMA variables are concerned.
RESULTS: Average SB index of the first two nights without the retainers was 3.0 ± 1.5, whilst the average values with the retainers in situ was 3.6 ± 1.9. ANOVA test showed the absence of significant differences between the four nights. Similarly, no differences were shown between the four nights as for the total number of sMMA events. Based on that, the null hypothesis was not rejected.
CONCLUSIONS: Findings suggest the absence of relevant effects of invisible orthodontic retainers on sMMA in healthy individuals during the short-term period.
PMID:30033479 | PMC:PMC6055222 | DOI:10.1186/s40510-018-0228-y
Class III malocclusion and bilateral cross-bite in an adult patient treated with miniscrew-assisted rapid palatal expander and aligners
Angle Orthod. 2018 Sep;88(5):649-664. doi: 10.2319/111617-790.1. Epub 2018 May 1.
ABSTRACT
This case report describes the use of a miniscrew-assisted rapid palatal expander and aligners to correct bilateral cross-bite and crowding in an adult patient with a Class III skeletal pattern. A digitally designed surgical guide was three-dimensionally printed and used to accurately insert four miniscrews into the palate; these were employed to anchor a novel miniscrew-assisted rapid palatal expander appliance without any dental anchorage. Cone-beam computed tomograms before and after miniscrew-assisted rapid palatal expander treatment demonstrated the orthopedic expansion of the maxilla without dental tipping. The patient was then fitted with aligners to correct crowding and malocclusion. This case report demonstrates the successful treatment of an adult patient with a narrow maxilla and bilateral cross-bite using a nonsurgical, conservative treatment.
PMID:29714067 | PMC:PMC8183134 | DOI:10.2319/111617-790.1
Class II subdivision correction with clear aligners using intermaxilary elastics
Prog Orthod. 2018 Sep 1;19(1):32. doi: 10.1186/s40510-018-0221-5.
ABSTRACT
BACKGROUND: To describe an esthetic orthodontic treatment using aligners in an adult patient with class II subdivision associated with crowding and dental crossbite. An 18-year-old hyperdivergent male patient with skeletal class II from mandibular retrusion presented for an orthodontic treatment. Occlusally, the patient presents class II subdivision, crossbite at tooth 4.4, an upper midline deviated towards the left with respect to the lower and facial midlines, and slight crowding in both arches. The patient refused conventional fixed multibracket treatment in favor of aligners. Pre- and post-treatment records as well as 1-year follow-up records are presented.
FINDINGS: Treatment objectives were achieved in 12 months, and the patient was satisfied with the functional and esthetic outcomes, which were stable at 1 year.
CONCLUSION: Combining aligners with appropriate auxiliaries is an efficacious means of resolving orthodontic issues such as class II, dental crossbite, and crowding in a time-frame comparable to that of conventional fixed orthodontics. Furthermore, this system is associated with optimal oral hygiene and excellent esthetics.
PMID:30171391 | PMC:PMC6119177 | DOI:10.1186/s40510-018-0221-5
Comparative analysis of jaw morphology and temporomandibular disorders: A three-dimension imaging study
Cranio. 2020 May;38(3):158-167. doi: 10.1080/08869634.2018.1507094. Epub 2018 Aug 14.
ABSTRACT
Objective: To investigate the association between volumetric measurements of craniofacial morphology and temporomandibular disorders (TMDs). Methods: Computerized tomography (CT) scans of 20 individuals aged 18 to 40 with (TMD group) or without TMJ pain (control group) were gathered based on a case-control design. Three-dimensional reconstructions were performed to evaluate the gonial angle, condylar volume, and the distance between the posterior edge of the condyle and the sigmoid notch. Results: The gonial angle was significantly larger (8% difference) in the TMD group with respect to controls, whereas the condylar volume was significantly higher in the control group (15.2% difference). No significant difference was found in the linear distance. Conclusion: There is an association between the presence of TMJ pain and some features of craniofacial morphology. Individuals with TMJ pain have a lower condylar volume and a tendency towards hyperdivergent growth.
PMID:30105940 | DOI:10.1080/08869634.2018.1507094
Class II treatment by palatal miniscrew-system appliance: A case report
Angle Orthod. 2020 Mar;90(2):305-313. doi: 10.2319/080218-559.1. Epub 2019 Mar 12.
ABSTRACT
This case shows that using a rapid palatal expander (RPE) and then a pendulum appliance anchored to palatal miniscrews is an option for improving treatment management in a noncompliant patient requiring maxillary expansion and molar distalization in the late mixed dentition. First, an RPE was used to expand the maxillary arch. Then, a modified pendulum appliance was used to distalize the maxillary first permanent molars. Optimal positioning of two palatal miniscrews enabled both appliances to be supported by skeletal anchorage. Treatment was finished using multibracket fixed appliances, and after 2 years, skeletal Class I as well as dental Class I canine and molar relationships were achieved.
PMID:30860863 | PMC:PMC8051236 | DOI:10.2319/080218-559.1
Efficacy of swm appliance in the expression of first-, second- and third-order information in Class I and Class II
J Clin Exp Dent. 2019 Jan 1;11(1):e97-e102. doi: 10.4317/jced.55399. eCollection 2019 Jan.
ABSTRACT
BACKGROUND: To assess the efficacy of a multibracket appliance-Straight-wire Mirabella (SWM) prescription-in terms of achieving the ideal first-, second- and third-order values proposed by Andrews.
MATERIAL AND METHODS: A total sample of 46 Caucasian subjects was divided into two groups: 23 with class I malocclusion (Group 1), and 23 with class II malocclusion (Group 2). The treatment protocol involved fixed multibracket appliances-SWM prescription-for both groups, with the addition of class II elastics for Group 2. Values for ΔU1-PP, ΔIMPA, in-out, tip and torque were measured on digital scans, and the results obtained were compared with the ideal values proposed by Andrews.
RESULTS: Statistically significant differences were revealed between the entire sample and Andrews’ values for: in-out on upper lateral incisors and upper canines; tip on the upper first premolars, upper second premolars, upper first molars and upper canines; and torque on the lower central incisors, lower lateral incisors, lower canines and lower first premolars. However, comparison of Groups 1 and 2 revealed statistically significant differences only at the lower lateral incisors. The use of class II elastics influenced ΔIMPA values, but not ΔU1-PP.
CONCLUSIONS: The efficacy of the multibracket appliance-SWM prescription-in expressing first- second- and, to a lesser extent, third-order information was demonstrated in both class I and class II malocclusions. Class II elastics only influenced the third-order expression on the lower lateral incisors and the ΔIMPA. Key words:Straight wire fixed appliances, prescription efficacy, Class I malocclusions, Class II malocclusions.
PMID:30697401 | PMC:PMC6343997 | DOI:10.4317/jced.55399
Corrigendum: Does low-frequency vibration have an effect on aligner treatment? A single-centre, randomized controlled trial
Eur J Orthod. 2019 Aug 8;41(4):444. doi: 10.1093/ejo/cjy084.
NO ABSTRACT
PMID:30649318 | DOI:10.1093/ejo/cjy084
The mechanical behavior of as received and retrieved nickel titanium orthodontic archwires
Prog Orthod. 2019 Jan 7;20(1):1. doi: 10.1186/s40510-018-0251-z.
ABSTRACT
OBJECTIVES: The aim of this study is to investigate and compare the characteristics of as received and retrieved NiTi archwires at a constant temperature by plotting their load/deflection graphs and quantifying three parameters describing the discharge plateau phase.
MATERIALS AND METHODS: Two hundred four NiTi archwires, traditional and heat-activated, of various cross sections, were obtained from 5 different manufacturers. Specimens prepared from the selected wires were subjected to a three-point bending test where 92 were retrieved through an in vivo retrieval protocol (crowding group C1 and group C2), 56 went through an in vitro retrieval protocol, and 56 were as received. The in vitro retrieval protocol was performed by a gear motor connected to a stainless steel support that performed fatigue cycles to the bent wires in artificial saliva. The load/deflection graphs of as received and retrieved wires were described through three parameters and the results were analyzed with classification and regression trees (CART) and analysis of variance (ANOVA).
RESULTS: Statistically significant differences between as received and retrieved wires were found only for the parameter plateau slope which represents the constancy of force expressed by the wire.
CONCLUSIONS: The aging of NiTi archwires influences the force constancy expressed. The behavior of the wires changes depending on the size, brand, and type of retrieval protocol. In terms of performance, the poorest is represented by all wires retrieved in vitro and in vivo group C2 (moderate to severe crowding).
PMID:30613836 | PMC:PMC6321830 | DOI:10.1186/s40510-018-0251-z