Changes in temporomandibular joint disc position and form following Herbst and fixed orthodontic treatment

Adolescent Patient's Perceptions During Treatment With Class II Elastics

The article presents a case of a 13-year-old adolescent male patient who started orthodontic treatment at the age of 12. Before treatment, he was diagnosed with narrow maxilla, proclination of upper incisors, deep overbite, distal occlusion bilaterally with significant sagittal overjet in frontal area, skeletal Class II, and hypodivergent growth pattern. During treatment, the patient is in his pubertal growth spurt. About 2 months after intermaxillary Class II elastics (1/4 heavy, 6.5 Oz) were applied, he complained of pain during mastication, wide opening of the mouth, and sometimes during protrusive and lateral movements in the right TMJ. The TMJ X-ray examination did not reveal abnormal morphological changes. Occlusion was evaluated by an electromyographic device, Teethan. The result was typical for Class II malocclusion. During the bilateral palpation of the zones of TMJ and opening of the mouth and chewing, the patient reported pain on the right side. There was no clicking in the joint. The elastic wear was stopped, and soon afterwards, the pain disappeared. These complaints point to a possible relationship between orthodontic treatment and TMJ pain. However, the disappearance of complaints after the removal of the Class II elastics points that the temporomandibular joint disorder (TMD) symptoms are reversible and resolved.

Efficacy of Arthrocentesis and Anterior Repositioning Splints in Treatment of Internal Derangement of TMJ: A Prospective Clinical Study

The aim of this study is to assess the efficacy of double puncture arthrocentesis and anterior repositioning splints in the treatment of internal derangement of temporomandibular joint. 35 patients with mean age of 36.6 years ± 10.2 years diagnosed with unilateral TMD who fell into Wilkes stage 2 and disc displacement with reduction with intermittent locking described by RDC/TMD were treated with Nitzan's double puncture arthrocentesis and were given a anterior repositioning hard splint. The parameters following parameters were assessed at intervals of 1 week, 2 weeks, 1 month, 3 months and 6 months: pain, maximum inter-incisal mouth opening, Joint noise/click. Statistically significant (p < 0.001) improvements were seen at all recorded intervals in all observed parameters. Simultaneous arthrocentesis and anterior repositioning splint therapy is effective in alleviating pain and improving mouth opening without discomfort in patients with unilateral painful TMD showing disc displacement with reduction with intermittent locking.

An Overview of Anterior Repositioning Splint Therapy for Disc Displacement-related Temporomandibular Disorders

Anterior repositioning splint (ARS) therapy is considered one of the most effective therapies for treating disc displacement-related temporomandibular disorders (TMDs), which account for a large proportion of TMD cases. Owing to the wide application of this therapy, the exact mechanism of remission has increasingly drawn attention. Given that practitioners have different views on ARS therapy, its indications are broadened, and operating methods diverged. This review attempts to provide an overview of ARS therapy and helps practitioners establish indications and suitable operating methods. Representative views in the past 10 years were summarised, and conclusions were drawn as follows: The mechanism of ARS therapy is mainly attributed to internal derangement correction, improvement of stress distribution and recently reported joint remodeling. It has an evident effect in the short term, and the most prevalent operating methods are protruding the mandible to the edge-to-edge position and wearing the ARS for 24 hours daily for 3-6 months. However, long-term stability is not optimal, and thus indications should be selected carefully. Notably, most of the clinical studies in this field are case analyses with low-quality evidence. Well-designed RCTs are required to further validate relevant theories.

Are morphologic and topographic alterations of the mandibular fossa after fixed functional treatment detectable on tomograms? Visual classification and morphometric analysis

AIM

The goal was to evaluate if changes in morphology and topography of the mandibular fossa after Functional Mandibular Advancer (FMA) treatment are detectable on tomograms. Furthermore, the suitability of digital tomograms (DT) over magnetic resonance imaging (MRI) for this particular question was investigated.

MATERIALS AND METHODS

In all, 25 patients (14 female, 11 male) with a skeletal class II malocclusion received treatment with a FMA. DTs were available prior to (T1) and after (T2) FMA treatment. A total of 50 temporomandibular joints were investigated. The mandibular fossae were evaluated metrically and visually regarding treatment-induced alterations. A p < 0.05 was set as the level for statistical significance for all tests. Results were compared to the results of a recent MRI study.

RESULTS

Visual inspection of all 50 joints in the DT at T1 and T2 revealed no alterations of the fossa shape in the sagittal plane; 24 patients showed identical morphology of right and left joints. The metrical analysis revealed no significant changes regarding width, depth and ratio thereof between T1 and T2. There also were no bilateral differences. Another 18 different distance measurements between porion, mandibular fossa, articular eminence and pterygoid fossa showed no significant changes. There was no detectable proof of a fossa shift.

CONCLUSIONS

No changes in the sagittal plane, mandibular fossa, the articular tubercle, or a possible fossa shift were found in the DT of class II patients after FMA treatment. DT and MRI measurements and the visual inspection revealed identical findings; thus, DT appears to be a valuable research tool for sagittal analysis of mandibular fossa changes.

Temporomandibular disorders in growing patients after treatment of class II and III malocclusion with orthopaedic appliances: a systematic review

OBJECTIVE

To determine if the use of orthopaedic appliances in growing patients applied to correct Class II and III malocclusion is related to the development of temporomandibular disorders (TMD).

MATERIAL AND METHODS

A systematic review was conducted between 1960 and July 2017, based on electronic databases: PubMed, Cochrane Library, Embase, Medline, Scopus, EBSCOhost, Scielo, Lilacs and Bireme. Controlled clinical trials (CCTs) and randomized controlled trials (RCTs) were identified. The articles were selected and analyzed by two authors independently. The quality of the evidence was determined according to the guidelines of the Cochrane Risk Bias Assessment Tool and the Cochrane Quality Study Guide.

RESULTS

Seven articles were included, four CCTs and three RCTs. The studies were grouped according to malocclusion treatment in (a) class II appliances (n = 4) and (b) class III appliances (n = 3). The quality of evidence was low due to the high risk of bias, independent of the association reported. All studies concluded that the use of orthopaedic appliances would not contribute to the development of TMD.

CONCLUSIONS

The quality of evidence available is insufficient to establish definitive conclusions, since the studies were very heterogeneous and presented a high risk of bias. However, it is suggested that the use of orthopaedic appliances to correct class II and III malocclusion in growing patients would not be considered as a risk factor for the development of TMD. High-quality RCTs are required to draw any definitive conclusions.

Dentoskeletal effects of the forsus™ fatigue resistance device in the treatment of class II malocclusion: A systematic review and meta-analysis

OBJECTIVE:

The aim of this systematic review and meta-analysis is to quantitatively compare previous studies that evaluated skeletal and dentoalveolar effects of the Forsus™ Fatigue Resistance Device (FRD) in the treatment of Class II malocclusion with a matched untreated control group.

MATERIALS AND METHODS:

Four electronic searches PubMed, Web of Science, Cochrane Library, and Science Direct that were limited to articles on human studies comparing the effect of Forsus appliance with a matched control group in the treatment of Class II malocclusion from the year (2000–2017). An additional manual search was carried out by examining the references of the included articles, SEARCH terms included; Forsus and Class II malocclusion. The quality of the included studies was assessed using the modified methodological score for clinical trials. The data were analyzed using Michael Borenstein's Comprehensive Meta-Analysis Software (V3.3.070, Biostat, Inc., US).

RESULTS:

Seven studies were included comprising 273 participants (Forsus group = 142; control group = 131). The results indicated a statistical significant skeletal effect of the Forsus appliance on increasing the occlusal plane only (P < 0.001). The results also indicated a statistical significant (P < 0.001) dentoalveolar effects of the Forsus appliance on the following outcomes; protruding, proclining, and intruding lower incisors; retroclining upper incisors, distalizing and intruding upper molars, as well as reducing overjet and overbite.

CONCLUSIONS:

The Forsus™ showed positive effects on the maxillary incisors and first molars as well as overjet and overbite. However, multiple negative effects were reported on the occlusal plane and lower incisors that need to be considered when using such appliance in treating Class II malocclusion.

[Cone beam computed tomography analysis of the bony structure of the temporomandibular joint during two phase treatment with Herbst appliance]

OBJECTIVE

This study assessed the effects of two-phase treatment with Herbst appliance on the bony structure of the temporomandibular joint via cone beam computed tomography (CBCT) analysis.

METHODS

This study selected 15 patients exhibiting early permanent dentition and classⅡmalocclusion combined with mandibular retrusion treated by a two phase treatment (Herbst and fixed appliance). The CBCT scans of the patients were obtained at the following stages: 2 weeks before Herbst treatment (T1), at the start of treatment when the Herbst appliance was set in place (T2), immediately after removal of the Herbst appliance (T3), and immediately after removal of the edgewise appliance (T4). Three-dimensional reconstruction and related measurements were performed using InvivoDental software, and the acquired data were statistically analyzed.

RESULTS

1) CBCT showed a crescent-shaped hyperplasia at the posterior-superior border of the condyles that the outer edge was highly dense and the inner region was lowly dense in T3 in 14 patients (28 condyles). 2) In T3-T2 and T4-T1, the diameters of the anteroposterior condyles increased by 0.62 and 0.66 mm, respectively (P<0.01), and the condylar head height correspondingly increased by 0.54 and 0.53 mm (P<0.01).

CONCLUSIONS

Condylar growth remodeling occurs during Herbst treatment.
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Impact of functional mandibular advancement appliances on the temporomandibular joint - a systematic review

Background

Although many orthodontists have no doubts about the effectiveness of functional appliances for mandibular advancement, the impact on the temporomandibular joint (TMJ) is still in dispute. The objective of this systematic review is to examine the main effects on the TMJ of using functional appliances, both in healthy patients and in patients with a pre-existing disorder.

Material and Methods

A systematic review of the literature was conducted in accordance with the PRISMA guidelines. Only systematic reviews, meta-analyses, randomized clinical trials (RCTs), case-control studies and cohort studies were included. A detailed language-independent electronic search was conducted in the Pubmed, Scopus, Cochrane Library and Embase databases. All studies published between 2000 and 2015 were included.

Results

A total of 401 articles were identified. Of these, 159 were duplicates and were excluded. On reading the title and abstract, 213 articles were excluded because they did not answer the research question, leaving a total of 29 articles. These articles were read and assessed. Following critical reading of the full text, eight articles were excluded: seven because they were considered of low quality and one because it published redundant data. As a result, 21 articles were included.

Conclusions

After treatment with functional appliances, the condyle was found to be in a more advanced position, with remodelling of the condyle and adaptation of the morphology of the glenoid fossa. No significant adverse effects on the TMJ were observed in healthy patients and the appliances could improve joints that initially presented forward dislocation of the disk.

Key words:Temporomandibular joint, TMJ, orthodontic appliances, functional, mandibular advancement, herbst appliance, bionator.

Dental and skeletal changes in patients with mandibular retrognathism following treatment with Herbst and pre-adjusted fixed appliance

Objective

To assess the dentoskeletal changes observed in treatment of Class II, division 1 malocclusion patients with mandibular retrognathism. Treatment was performed with the Herbst orthopedic appliance during 13 months (phase I) and pre-adjusted orthodontic fixed appliance (phase II).

Methods

Lateral cephalograms of 17 adolescents were taken in phase I onset (T₁) and completion (T₂); in the first thirteen months of phase II (T₃) and in phase II completion (T₄). Differences among the cephalometric variables were statistically analyzed (Bonferroni variance and multiple comparisons).

Results

From T₁ to T₄, 42% of overall maxillary growth was observed between T₁ and T₂ (P < 0.01), 40.3% between T₂ and T₃ (P < 0.05) and 17.7% between T₃ and T₄ (n.s.). As for overall mandibular movement, 48.2% was observed between T₁ and T₂ (P < 0.001) and 51.8% between T₂ and T₄ (P < 0.01) of which 15.1% was observed between T₂ and T₃ (n.s.) and 36.7% between T₃ and T₄ (P < 0.01). Class II molar relationship and overjet were properly corrected. The occlusal plane which rotated clockwise between T₁ and T₂, returned to its initial position between T₂ and T₃ remaining stable until T₄. The mandibular plane inclination did not change at any time during treatment.

Conclusion

Mandibular growth was significantly greater in comparison to maxillary, allowing sagittal maxillomandibular adjustment. The dentoalveolar changes (upper molar) that overcorrected the malocclusion in phase I, partially recurred in phase II, but did not hinder correction of the malocclusion. Facial type was preserved.

Morphological Changes of Condyles and Helkimo Clinical Dysfunction Index in Patients Treated with Herbst - Orthodontic Appliance

This study evaluated the morphological changes in the temporomandibular joint (TMJ) condyles and calculated the Helkimo clinical dysfunction index (CDI) in adolescents with Class II Division 1 malocclusion and mandibular retrognathism treated with the Herbst appliance (phase I) and fixed orthodontic appliances (phase II). Thirty-two consecutive adolescents underwent phase I, and 23 completed phase II. The TMJs were evaluated qualitatively using magnetic resonance imaging (MRI) at the beginning of treatment (T1), during phase I (T2), at the end of phase I (T3) and at the end of phase II (T4). The CDI was calculated at T1, T3 and T4. From T1 to T3 (p=0.326), there were no changes in condyle morphology in 86.0% of the TMJs. From T3 to T4 (p<0.05) and T1 to T4 (p<0.05), changes occurred in 39.1% and 43.4% of the condyles. No significant changes in CDI occurred from T1 to T3, T3 to T4 and T1 to T4 (p=1.000; 86.6%, 76.2% and 76.2% concordance). After phase I, there were practically no changes in condyle morphology. At the end of phase II, a mild flattening was observed in some condyles. It may be concluded that no significant changes occurred in CDI after both treatment phases.