Treatment of a Case of Skeletal Class II Malocclusion with Temporomandibular Joint Disorder Using Miniscrew Anchorage

Correction of Severe Skeletal Class II High Angle with Mandibular Retrusion and Gummy Smile by Double-Jaw Surgery

This report describes the treatment of severe skeletal Class II malocclusion in a young woman with a gummy smile and pronounced lower anterior facial height. Overjet and overbite were +12.0 mm and -1.0 mm, respectively. Cephalometric analysis revealed inferior positioning of the maxilla and severe mandibular retrusion with clockwise rotation. Both the upper and lower anterior teeth showed labial inclination. Based on a diagnosis of a skeletal Class II high angle with mandibular retrusion and a gummy smile, double-jaw orthognathic surgeries for upper and lower premolar extraction were chosen to gain ideal occlusion and an improvement in the esthetic facial profile. Le Fort I osteotomy was performed to move the anterior and posterior teeth upward by 4.0 mm and achieve mandibular counterclockwise rotation. Short lingual sagittal split ramus osteotomy was performed to move the mandible forward by 3.0 mm. As a result, normal overjet and overbite were achieved together with a straight profile and a good smile. After surgery, electromyographic evaluation of anterior temporal muscle activity showed an improvement in the percentage overlapping coefficient value (a symmetric index of bilateral muscle activity) from 28.1% to 63.2% compared to at pre-treatment. The pattern of jaw movement also showed an improvement. These results suggest that orthognathic surgery in skeletal Class II cases can improve not only malocclusion and the skeletal relationship of the jaws, but also masticatory function and jaw movement.

Effect of computer-assisted design and manufacturing cutting and drilling guides accompanied with pre-bent titanium plates on the correction of skeletal class II malocclusion: a randomized controlled trial

This study was performed to assess the effect of correcting skeletal class II malocclusion based on the application of computer-assisted design and manufacturing (CAD/CAM) cutting and drilling guides accompanied with pre-bent titanium plates. Fifty patients with skeletal class II malocclusion were recruited into this prospective randomized controlled clinical trial and assigned to two groups. Patients underwent bilateral sagittal split ramus osteotomy directed by CAD/CAM cutting and drilling guides accompanied with pre-bent titanium plates (group A) or CAD/CAM splints (group B). Postoperative assessments were performed. Differences between the virtually simulated and postoperative models were measured. Patients in both groups had a satisfactory occlusion and appearance. More accurate repositioning of the proximal segment was found in group A than in group B when comparing linear and angular differences to reference planes; however, no significant difference was revealed for the distal segment. In conclusion, CAD/CAM cutting and drilling guides with pre-bent titanium plates can provide considerable surgical accuracy for the positional control of the proximal segments in bilateral sagittal split ramus osteotomy for the correction of skeletal class II deformities.

[Progress on clinical application of orthodontic-implant combined therapy]

For complex implant cases, simple implantation could not achieve the desired therapeutic effect, and a multidisciplinary approach has become a general trend. Orthodontic treatment before implantation creates favorable conditions for subsequent implantation by increasing restoring three-dimensional space, improving occlusion of patients. It also stimulates the increase of autologous soft and hard tissue while biological potential of periodontal ligament is fully developed. The choice of operation time is vital to keep the level of soft and hard tissue at the implantation site, which improves the curative effect of implantation in terms of function and aesthetics. In this article, the orthodontic-implant combined therapy is briefly reviewed focusing on the three-dimensional space optimization, implant site enhancement by orthodontic extrusion and delayed orthodontic space opening.

Correction of skeletal class II severe open bite with temporomandibular joint disorder treated by miniscrew anchorage and molar extraction: a case report

BACKGROUND

Little information is available on the treatment of open bite with temporomandibular joint disorder by intrusion of molars using miniscrews.

CASE PRESENTATION

This case report describes a 42-year-old Japanese woman with a skeletal class II severe anterior open bite and temporomandibular joint disorder. The pretreatment magnetic resonance imaging of both temporomandibular joints revealed osteoarthritis and anterior disc displacement without reduction in both temporomandibular joints. A stabilization splint was used before orthodontic treatment and bilateral upper and lower premolars were extracted. Miniscrews were inserted into the palatal region to intrude the maxillary molars and avoid loss of anchorage. The maxillary left first molar was also extracted to improve the molar relationship and the dental midline. Normal overjet and overbite with Angle class I molar relationship were achieved, and the upper and lower midlines coincided. Our patient's teeth continued to be stable and her temporomandibular joint was asymptomatic after a retention period of 2 years.

CONCLUSIONS

Intrusion of molars by miniscrews is available for skeletal class II severe open bite.

[Treatment goals in FACE philosophy]

INTRODUCTION

The FACE philosophy is characterized by clearly defined treatment goals: facial esthetics, dental esthetics, periodontal health, functional occlusion, neuromuscular mechanism and joint function. The purpose is to establish ideal occlusion with good facial esthetics and an orthopedic stable joint position.

MATERIALS AND METHODS

The authors present all the concepts of FACE philosophy and illustrate them through one case report.

RESULTS

Taking into account all the FACE philosophy concepts increases diagnostic ability and improves the quality and stability of treatment outcomes.

DISCUSSION

The goal of this philosophy is to harmonize the facial profile, tooth alignment, periodontium, functional occlusion, neuromuscular mechanism and joint function. The evaluation and treatment approach to vertical problems are unique to the philosophy.

Relationship between orthodontics and temporomandibular disorders

Since the end of the 20th century, the problems of the temporomandibular disorders (TMDs) have aroused interest to the orthodontists. The aim of this literature review is to present the contemporary evidence concerning the association between the presence of malocclusions and the occurrence of signs and symptoms of the TMJ. In addition, additional variables, which may affect the TMJs of a patient during the orthodontic treatment are pointed out. It is evident that there is an increased number of patients who are seeking for orthodontic treatment, not only in order to enhance their facial aesthetics and the function of mastication system, but also to relieve the symptoms of the temporomandibular joint (TMJ). There are multiple etiological factors that have been associated with the TMDs and they may be manifested by pain and/or sounds of TMJ. In addition, during the clinical examination it can be detected a deviation from the normal function of the mandible.

Long-term stability of conservative orthodontic treatment in a patient with temporomandibular joint disorder

This article reports the orthodontic treatment of a 20-year-old patient with dental crowding and temporomandibular joint disorders (TMDs). The patient presented moderate anterior crowding with a Class I molar relationship and masticatory disturbance in the mandibular position induced by previous splint therapy. Orthodontic treatment with multi-bracket appliance was initiated to correct the anterior crowding in both dental arches, after the extraction of first premolars and third molars, and also to maintain the splint-induced position of the condyles. After 26 months of treatment, an acceptable occlusion was achieved without any TMD symptoms. After 18-month retention, flattening on the right condyle was observed, possibly as an adaptative remodeling. After 16-year retention period, the occlusion was maintained without recurrence of any TMD symptoms, indicating a long-term stability of occlusion and temporomandibular joint (TMJ) components. Our results suggest the possibility of compromised treatment in patients with TMD to achieve a long-term stability in occlusion and TMJ function.

Temporomandibular disorders and eating disorders: a literature review

INTRODUCTION

Temporomandibular disorders (TMD) and eating disorders (ED) affect function and parafunction of the oral cavity and have high rates of medical and psychological comorbidity. However, little is known about the possible associations between them, and few studies have investigated the existence of such associations.

METHODS

A search was conducted on the SciELO, LILACS, and PubMed/MEDLINE databases to find relevant articles written in English and Portuguese. Only studies involving human beings were included, and there was no limit for year of publication.

RESULTS AND CONCLUSIONS

There is evidence of the correlation between TMD and ED, but their comorbidity must be better understood. The presence of depressive symptoms is an aggravating factor that must also be taken into account during the diagnosis and treatment of those patients.

Synovial fluid dynamics with small disc perforation in temporomandibular joint

The articular disc plays an important role as a stress absorber in joint movement, resulting in stress reduction and redistribution in the temporomandibular joint (TMJ). The flow of synovial fluid in the TMJ may follow a regular pattern during movement of the jaw. We hypothesised that the regular pattern is disrupted when the TMJ disc is perforated. By computed tomography arthrography, we studied the upper TMJ compartment in patients with small disc perforation during jaw opening-closing at positions from 0 to 3 cm. Finite element fluid dynamic modelling was accomplished to analyse the pattern of fluid flow and pressure distribution during the movements. The results showed that the fluid flow in the upper compartment generally formed an anticlockwise circulation but with local vortexes with the jaw opening up to 2 cm. However, when the jaw opening-closing reached 3 cm, an abnormal flow field and the fluid pressure change associated with the perforation may increase the risk of perforation expansion or rupture and is unfavourable for self-repair of the perforated disc.