Andrea Bargellini; Tommaso Castroflorio; Federica Casasco; Maria Giacone; Francesco Garino; Giovanni Cugliari; Andrea Deregibus
Abstract
Background: In the last years an increasing number of patients have sought for comfortable and aesthetic alternatives to fixed appliances. Aligners, due to the protection against tooth wear, can be compared to occlusal splints used in patients suffering from sleep bruxism (SB). The aim of the study was ...
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Background: In the last years an increasing number of patients have sought for comfortable and aesthetic alternatives to fixed appliances. Aligners, due to the protection against tooth wear, can be compared to occlusal splints used in patients suffering from sleep bruxism (SB). The aim of the study was to analyze the effects of clear aligners on SB episodes using a validated portable device (Bruxoff®, OTBioelettronica, Torino, Italy) allowing a simultaneous recording of electromyographic signals from both the masseter muscles as well as heart frequency to evaluate variation on SB activity.
Methods: Forty patients were analyzed for the study. Twenty of them were assigned to orthodontic treatment with clear aligners (Invisalign®, Align Technology). The other twenty patients were used as control group observed for a period of twelve months. Intra-group and inter-group variances were analyzed by using a two-way ANOVA test. For each analysis a P < 0.05 was set. Results: After the first month of clear aligners therapy, all patients in the case group showed a significant reduction in the number of SB episodes (P < 0.05). However, after three months SB values returned to baseline levels. The number of tonic contractions were reduced even after three months of orthodontic treatment (P < 0.05).
Conclusions: While clear aligners seem to be capable to reduce clenching, i.e. occlusal load, in SB patients, the grinding activity seems to be not influenced by those appliances at least in the short term of the present investigation.
Susan Sadeghian
Abstract
Aim: The purpose of this study was toevaluate the relationship between the ultrasonographic thickness of masseter muscle and the width of dental arches.Materials and Methods: The sample comprised of 44 persons (22males, 22females), who did not undergo orthodontic treatment and they had at least 28 teeth ...
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Aim: The purpose of this study was toevaluate the relationship between the ultrasonographic thickness of masseter muscle and the width of dental arches.Materials and Methods: The sample comprised of 44 persons (22males, 22females), who did not undergo orthodontic treatment and they had at least 28 teeth with CL 1 occlusion. The thickness of the masseter muscle was measured ultrasonografically with the muscles both in relaxation and under contraction. Maxillary and madibular inter-molar and inter-canine width were measured with an digital caliper for the distance between the palatal surfaces of the permanent first molar and cingulumes of canines.Results: There was a significant association between mandibular inter-molar width and sex (PV=0.037). Masseter muscle thickness in both sides and either in relaxation or contraction showed a direct significant association with sex (PV=0.001). Maxillary inter-molar and inter- canine and mandibular inter-canine width showed a direct significant association with masseter thickness during contraction in tight side (PV=0.037), whereas in relaxation no statistically significant relationship was found (PV =0.07).Conclusions: The fmdings of this study indicated that the thickness and functional capacity of the masseter muscle may be considered as one of the factors influencing the width of the maxillary dental arch and inter canine mandibular dental arch width.
