Multimodality treatment for rehabilitation of adult orthodontic patient with complicated dental condition and jaw relation.

A 50-year-old man with severe malocclusion requested comprehensive oral rehabilitation. He presented with retrognathic mandible, anterior deep bite and a gummy smile in the premaxilla, and tenting occlusal plane with severe buccal crossbite of the left maxillary posterior teeth. Inappropriate fixed prostheses spanned the maxilla and the mandible with a class II jaw relationship. A detailed analysis indicated the need for orthodontic treatment, orthognathic surgery, bone graft at the deficient alveolar ridge for implant surgery and a revision of all prostheses. Over a 2-year-period of management, the patient received anterior osteotomy for intrusion of lower anterior teeth, bilateral sagittal splitting osteotomy for mandible advancement and posterior osteotomy for inward upward repositioning of posterior teeth of the left maxilla to correct major jaw deformities. The deficient alveolar ridge in the premaxilla was augmented by autogenous bone graft harvested during the orthognathic surgery. He sequentially had mini-plate and dental implant as anchorage assisting teeth alignment in the mandible. Two 3-fixture-supported implant prostheses were delivered in the premaxilla and the mandible. The improvement in cosmesis, stability and function through treatment and a 2-year clinical follow-up were considered satisfactory.

Triple immediate therapy (ridge expansion, soft tissue augmentation, and provisional restoration) of maxillary anterior single implant.

BACKGROUND: Immediate restoration during implant placement in the premaxillary area can achieve a favorable esthetic result. However, the treatment always poses a great challenge to clinicians, especially for patients with preexisting soft and hard tissue deficiencies. The aim of this clinical report was to present a protocol for a multidisciplinary approach to provide an immediate implant restoration for patients with ridge deficiency. METHODS: A 21-year-old female presented with a mesial shift of the maxillary right canine due to loss of a lateral incisor at an early age. The treatment protocol included orthodontic space redistribution to open a canine space for implant placement. Subsequently, ridge expansion and implant placement combined with connective tissue grafting for the reconstruction of the soft tissue profile were performed, and an immediate provisional prosthesis was delivered simultaneously. A definitive University of California at Los Angeles-style ceramometal crown was completed 6 months later with periodical clinical maintenance. RESULTS: The 18-month postoperative follow-up revealed that the implant was stable, and the buccal depression of the surgical area was reconstructed. Papillae were augmented, and a harmonious soft tissue margin was achieved in the esthetic zone. Radiographs demonstrated a normal vertical osseous height and excellent osseointegration of the implant. CONCLUSIONS: The combination technique of ridge expansion and soft tissue augmentation can be applied to immediate implant restoration cases without the need for complicated bone grafting surgeries in atrophic ridges. This triple immediate strategy enabled us to reduce the number of surgeries, which simplified the overall procedure without compromising the esthetic results.

Stiffness and frictional resistance of a superelastic nickel-titanium orthodontic wire with low-stress hysteresis.

INTRODUCTION: Stress-induced martensite formation with stress hysteresis that changes the elasticity and stiffness of nickel-titanium (Ni-Ti) wire influences the sliding mechanics of archwire-guided tooth movement. This in-vitro study investigated the frictional behavior of an improved superelastic Ni-Ti wire with low-stress hysteresis. METHODS: Improved superelastic Ni-Ti alloy wires (L & H Titan, Tomy International, Tokyo, Japan) with low-stress hysteresis were examined by using 3-point bending and frictional resistance tests with a universal test machine at a constant temperature of 35 degrees C, and compared with the former conventional austenitic-active superelastic Ni-Ti wires (Sentalloy, Tomy International). Wire stiffness levels were derived from differentiation of the polynomial regression of the unloading curves, and values for kinetic friction were measured at constant bending deflection distances of 0, 2, 3, and 4 mm, respectively. RESULTS: Compared with conventional Sentalloy wires, the L & H Titan wire had a narrower stress hysteresis including a lower loading plateau and a higher unloading plateau. In addition, L & H Titan wires were less stiff than the Sentalloy wires during most unloading stages. Values of friction measured at deflections of 0, 2, and 3 mm were significantly (P <.05) increased in both types of wire. However, they showed a significant decrease in friction from 3 to 4 mm of deflection. L & H Titan wires had less friction than Sentalloy wires at all bending deflections (P <.05). CONCLUSIONS: Stress-induced martensite formation significantly reduced the stiffness and thus could be beneficial to decrease the binding friction of superelastic Ni-Ti wires during sliding with large bending deflections. Austenitic-active alloy wires with low-stress hysteresis and lower stiffness and friction offer significant potential for further investigation.