Severe open bite due to traumatic condylar fractures treated nonsurgically with implanted miniscrew anchorage

Vertical Control of a Severe Hyperdivergent Skeletal Class II Malocclusion with Steep Posterior Occlusal Plane in a Camouflage Case

Severe hyperdivergent skeletal Class II malocclusion may be ideally treated with orthognathic surgery in adult patients. Here, we report a camouflage treatment of a 23-year-old female patient. She was diagnosed with a skeletal Class II malocclusion with extreme high mandibular plane angle, retrusive mandible, steep posterior occlusal plane, anterior open bite, and severe overjet. The treatment plan included extraction of all second premolars and intrusion of the maxillary anterior teeth and mandibular posterior teeth using miniscrews. These contributed to an effective counterclockwise rotation of the mandible, decreased lower face height, and improvement in anterior overbite. This case report shows a vertical control strategy on severe hyperdivergent skeletal Class II malocclusions, which achieves well-controlled sagittal and vertical dimensions and a favorable facial appearance. The treatment and retention results were well balanced and aesthetically pleasing.

Fabrication and evaluation of customized implantable drug delivery system for orthopedic therapy based on 3D printing technologies

A customized implantable drug delivery system with the dual functions of playing a supporting role and providing continuous bacteriostasis is of great importance during the treatment of bone defect diseases. The main objective of this study was to explore the potential of using three-dimensional (3D) printing technologies to fabricate customized implants. Ciprofloxacin hydrochloride (Cipro) was chosen as the model drug, and two printing technologies, semisolid extrusion (SSE) and fused deposition modeling (FDM) were introduced. Six kinds of implants with customized irregular shapes were printed via FDM technology. Two kinds of implants with customized dosages were constructed via SSE technology. In addition, three kinds of implants with customized internal structures were produced via FDM and SSE technologies. The data for morphology, dimensions and mechanical properties demonstrated satisfactory printability and good printing accuracy when applying SSE and FDM technologies to produce the customized implants. The dissolution curves indicated that the desired customized drug release could be achieved by designing the specific internal structures. The biocompatibility examination showed that the printed implants possessed outstanding biocompatibility. In conclusion, all results suggested that 3D printing technologies provide a feasible method and novel strategy to fabricate customized implantable drug delivery systems.

Comparative evaluation of bite force in patients treated for unilateral mandibular condylar fractures by open and closed methods

BACKGROUND/AIM

Condylar fractures account for a large proportion (20% to 52%) of mandibular injuries. The goal of treating these fractures is to restore the occlusion, thereby re-establishing the masticatory function as close as possible to the patient's pre-trauma state. The aim of this study was to compare the bite forces following unilateral condylar fractures treated by open reduction and internal fixation (ORIF) with those managed by the closed method.

METHOD

Patients with unilateral mandibular condylar fractures were divided into two groups (n = 20) using a simple randomization method. Patients in group I were treated by open reduction and internal fixation (ORIF) using titanium miniplates and screws. Patients in group II were treated by the closed method with inter-maxillary fixation. Patients in both groups were evaluated pre-operatively and then post-operatively at one week, one month and three months for maximum bite force achieved at the central incisor, premolar and molar regions.

RESULTS

Pre-operative bite forces on the unaffected site were significantly higher than the affected site in both groups, whereas no significant difference was observed in bite forces between the unaffected and affected sites in both groups post-operatively. The bite forces achieved at both the unaffected and affected sites in the ORIF group were significantly higher than in the closed group.

CONCLUSION

Maximum bite forces differed significantly when the treatment was done with the open method, and the patients treated with the open method needed less time to achieve the maximum bite forces, thereby making an earlier return to function.

Extracapsular Condylar Fractures Treated Conservatively in Children: Mechanism of Bone Remodelling

OBJECTIVE

This study aims to reveal the reconstruction process in pediatric patients with extracapsular condylar fractures after conservative treatment. We clarify that the "upright" position (or "recontouring" or favorable prognosis) of condyles is not a result of the anatomical reduction of the deviated condylar processes but originates from the remodeling of the skeleton. We also explore the related mechanism.

METHODS

The sample consisted of 27 pediatric patients aged less than 12 years who presented with extracapsular condylar fractures and were treated conservatively within an 8-year period (June 2011-April 2019). Data on the age, gender, date of injury, mechanism of trauma, location and pattern of mandibular condylar fracture and associated injuries and treatment methods of the patients were obtained. The process of bone remodeling in condyles was also recorded and analyzed.

RESULTS

The 27 children in this study sustained 33 extracapsular condylar fractures over the 8-year period of record retrieval. Amongst these fractures, 8 (24.2%) and 25 (75.8%) were condylar neck and condylar base fractures, respectively. Deviation and green-stick fractures were the predominant types and accounted for over 3 quarters of the condylar neck and base fractures (28, 84.8%), followed by dislocation fracture (3, 9.1%), displacement fracture (1, 3.0%), and non-displaced fracture (1, 3.0%). The period of follow-up ranged from 2 days to 257 days (average, 58.78 days). Only 1 patient with bilateral extracapsular condylar fractures showed vertically reconstructed condyles, which indicates an upright position of the condylar processes. One patient showed less angulation after treatment than before treatment, 1 patient revealed greater angulation after treatment than before treatment and all other patients (20 patients) showed the same angulation pre- and post-treatment. Both patients with only extracapsular condylar fractures showed no obvious deviations in dentition and facial asymmetry after their injury and treatment. The shortest and longest times observed for bone remodeling were 33 and 256 days, respectively. Children whose condylar head remained completely or at least partly inside the glenoid fossa showed satisfactory remodeling results during follow-up. Computed tomography scan during follow-up generally showed bone regeneration in the lateral condyle articular surface and the medial portion of the ascending ramus and bone resorption in the displaced direction (ie, the medial condyle head became sharp). Condylar heads displaced completely outside of the glenoid fossa showed serious shortening of the ascending ramus, and no obvious bone remodeling was observed. Only 1 patient with bilateral extracapsular condylar fractures showed a normal contour (ie, a vertically reconstructed condyle reflecting the upright position of the condylar processes) after 8 months.

CONCLUSION

Stress stimulation originating from the glenoid fossa and ascending ramus of the mandible is a prerequisite for good condylar reconstruction. Conservative treatment could be carried out if the condylar head remains completely or at least partly inside the glenoid fossa. When the condylar head is dislocated completely outside the glenoid fossa, the glenoid-condylar relationship ceases to exist, joint function is lost and the height of the ascending ramus is significantly reduced. In this case, open reduction may be suitable.

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.

Anterior Bite Opening in Adulthood

Objectives

To study anterior bite opening of unknown cause presenting in adulthood regarding prevalence, symptoms of Temporomandibular Dysfunction (TMD) and possible causes of the bite opening.

Methods

Patients referred to two Orofacial Pain and TMD clinics with the complaint of recent anterior bite opening, presenting in adulthood and of unknown cause, were considered for the study. Patients with systemic rheumatic or neuromuscular diseases, degenerative joint disease, previous fractures of the jaws or orthodontic treatment, were excluded. The clinical examination was according to DC/TMD and extended for the occlusion. Reported symptoms, clinical signs, the occlusion and diagnoses found are presented. According to the information gained from the patient's history, previous occlusion and appearance, and present signs of parafunction, a possible association with the bite opening was suggested.

Results

Anterior bite opening was found in 1.6% of the referred patients. Symptoms of tiredness and/or orofacial pain were reported by 62%, headache by 41%, TMJ clicking by 24% and sensitive/tender teeth by 41%. Parafunction or bruxism was reported by 2/3 of the patients. A previous period in life of TMD symptoms, before the bite opening, was reported by 66%. Myalgia and headache associated with TMD were frequently diagnosed. The use of a partial dental splint, tongue pressure and pregnancy were possible causes found for the bite opening.

Conclusion

Anterior bite opening can occur in adulthood without organic or systemic disease of the TMJ or masticatory muscles, and was frequently associated with muscle TMD symptoms.

Class II malocclusion with complex problems treated with a novel combination of lingual orthodontic appliances and lingual arches

This case report describes a novel method of combining lingual appliances and lingual arches to control horizontal problems. The patient, who was 25 years of age at her first visit to our hospital with a chief complaint of crooked anterior teeth, was diagnosed with skeletal Class II and Angle Class II malocclusion with anterior deep bite, lateral open bite, premolar crossbite, and severe crowding in both arches. She was treated with premolar extractions and temporary anchorage devices. Conventionally, it is ideal to use labial brackets simultaneously with appliances, such as a lingual arch, a quad-helix, or a rapid expansion appliance, in patients with complex problems requiring horizontal, anteroposterior, and vertical control; however, this patient strongly requested orthodontic treatment with lingual appliances. A limitation of lingual appliances is that they cannot be used with other conventional appliances. In this report, we present the successful orthodontic treatment of a complex problem using modified lingual appliances that enabled combined use of a conventional lingual arch.

Correction of the occlusal and functional sequelae of mandibular condyle fractures using orthodontic mini-implant molar intrusion

We report on the non-surgical management of an adult female whose bilateral mandibular condylar fractures had resulted in a clockwise (posterior) mandibular rotation, limitation of mandibular movements and increased occlusal loading on the molar teeth. She refused maxillary surgery and was treated with a minimally-invasive approach, involving orthodontic fixed appliances and mini-implant intrusion of the maxillary molar teeth. This provided both occlusal and functional improvements, including a significant increase in the inter-incisal distance, which were stable after one year of retention.