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Dental implant procedures, both surgical placement and preimplant bone augmentation, have become an integral aspect of the oral and maxillofacial surgeon's practice. The number of dental implants placed each year continues to increase as a result of increasing patient exposure and awareness of dental implants, the increased functional and esthetic dental demands of general practitioners and patients, the overall increase in age of the US patient population, and expanded insurance coverage of dental implant-related procedures. This article outlines relevant surgical procedures aimed toward reconstructing alveolar ridge defects to restore intra-arch alveolar discrepancies before restoration-driven dental implant placement., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Complete dislocation of the globe, inferiorly into the maxillary sinus, medially into the ethmoid sinus, or superiorly into the anterior cranial fossa, can occur with significant blunt facial trauma. The degree of injury to the globe, its adnexal structures, and the optic nerve is dependent on the extent of the dislocation. Complete traumatic subluxation of the globe into the maxillary sinus is associated with severe injury to the periocular structures and represents a challenging and unique reconstructive process rarely encountered in published studies. The present case report represents only the 15th reported case of complete orbital prolapse into the maxillary sinus. Controversy exists regarding the definitive treatment of traumatic globe dislocations, the risk of sympathetic ophthalmia (SO), the sequela of postenucleation socket syndrome, and prophylactic steroid treatment to decrease the incidence of SO and traumatic optic neuropathy., (Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate a bimatoprost gel for enhancing eyelash growth, adverse effects, and change in intraocular pressure (IOP)., Methods: Prospective, double-masked, randomized controlled study. Fifty-two patients without ocular disease were assigned a control or bimatoprost 0.03% gel to apply to the eyelid margin once a day., Results: The adjusted mean change in eyelash length from baseline to 6 months was 0.77 mm in the bimatoprost group and -0.12 mm in the control group (P = 0.004). Adverse effects were experienced by 2 of 16 patients (12.5%) in the control group and 9 of 36 patients (25%) in the bimatoprost gel group. Mean change in IOP from baseline to 6 months was 0.685 mmHg in the control group and -2.04 mmHg in the bimatoprost group (P = 0.009)., Conclusions: Bimatoprost gel was effective in enhancing eyelash growth. The most common adverse effect for the bimatoprost gel was conjunctival and eyelid hyperemia, while the most severe was recurrent anterior uveitis. Mean IOP was reduced in subjects using the bimatoprost gel.

This report reviewed the published data concerning different methods for vertical augmentation of the posterior mandible for implant placement. The main purpose was to compare and contrast the different treatment methods, with a more detailed review of the use of the interpositional osteotomy to vertically augment the posterior mandible. After the data review, we present a case illustrating this method. On the basis of the data review, the use of the interpositional osteotomy might be the method of choice for select patients.

Patients who need implant-supported prostheses in the maxilla might not have sufficient bone height in the posterior region for implants. Treatment alternatives in such cases include either bone graft augmentation followed by implants or nongrafting options. This report discusses 2 nongrafting options for prosthetic rehabilitation in these patients. An extensive summary of the published data has been performed to provide evidence for these recommendations.

The differential diagnosis for monoarticular arthritis is extensive. Patient omissions from the history can compound this broad diagnostic dilemma. A case report is presented of a 32-year-old female with an eight-month history of isolated right first metatarsophalangeal joint (MTPJ) pain, after exhaustive, non-specific diagnostic evaluation. An open biopsy was performed, and a 3.5 cm wooden foreign body, believed to be the result of an injury 18 years prior, was excised from the 1st MTP. Open biopsy may be required as an important part of the workup for definitive diagnosis of a foreign body synovitis. A discussion regarding the presentation, clinical and diagnostic findings follows.

Object: Interbody fusion devices are rapidly gaining acceptance as a method of ensuring lumbar interbody arthrodesis. Although different types of devices have been developed, the comparative reconstruction stability remains controversial. It also remains unclear how different stress-shielded environments are created within the devices. Using a calf spine model, this study was designed to compare the construct stiffness afforded by 11 differently designed lumbar interbody fusion devices and to quantify their stress-shielding effects by measuring pressure within the devices., Methods: Sixty-six lumbar specimens obtained from calves were subjected to anterior interbody reconstruction at L4-5 by using one of the following interbody fusion devices: four different threaded fusion cages (BAK device, BAK Proximity, Ray TFC, and Danek TIBFD), five different nonthreaded fusion devices (oval and circular Harms cages, Brantigan PLIF and ALIF cages, and InFix device); two different types of allograft (femoral ring and bone dowel) were used. Construct stiffness was evaluated in axial compression, torsion, flexion, and lateral bending. Prior to testing, a silicon elastomer was injected into the cages and intracage pressures were measured using pressure needle transducers., Conclusions: No statistical differences were observed in construct stiffness among the threaded cages and nonthreaded devices in most of the testing modalities. Threaded fusion cages demonstrated significantly lower intracage pressures compared with nonthreaded cages and structural allografts. Compared with nonthreaded cages and structural allografts, threaded fusion cages afforded equivalent reconstruction stiffness but provided more stress-shielded environment within the devices.

This study examines the biomechanical effects of interbody cages and variations in posterior rod diameter in a simulated single-level spinal fusion. A single-level spinal fusion model composed of polyethylene cylinders, posterior pedicular instrumentation, and variously positioned single or dual interbody cages was used for biomechanical testing. Constructs were tested under compressive flexural load, with measurement of stiffness, rod strain, cage strain, and intracage pressure. A strong linear correlation emerged between the mean construct stiffness and cage positioning within the sagittal plane that was inversely related to posterior rod strain. Two small titanium mesh cages were equivalent to one large cage. In a single-level spine model, the presence of and sagittal position of interbody cages significantly influences overall construct stiffness. Cage strain increased with more anterior positions and was inversely related to rod strain.

Study Design: The stabilizing effects of five different occipitocervical fixations were compared., Objectives: To evaluate the construct stability provided by five different occipito-atlanto-axial fixation techniques., Summary of Background Data: Few studies have addressed occipitocervical reconstruction stability and no studies to data have investigated anterior-posterior translational stiffness., Methods: A total of 21 human cadaveric spines were used. After testing intact spines (CO-C2), a type II dens fracture was created and five different reconstructions were performed: 1) occipital and sublaminar wiring/rectangular rod, 2) occipital screws and C2 lamina claw hooks/rod, 3) occipital screws, foramen magnum screws, and C1-C2 transarticular screws/rod, 4) occipital screws and C1-C2 transarticular screws/Y-plate, and 5) occipital screws and C2 pedicle screws/rod. Biomechanical testing parameters included axial rotation, flexion/extension, lateral bending, and anterior-posterior translation., Results: Pedicle screw fixation demonstrated the highest stiffness among the five reconstructions (P < 0.05). The two types of transarticular screw methods provided greater stability than hook or wiring reconstructions (P < 0.05). The C2 claw hook technique resulted in greater stability than sublaminar wiring fixation in anterior-posterior translation (P < 0.05). However, the wiring procedure did not significantly increase the stiffness levels beyond the intact condition under anterior-posterior translation and lateral bending (P > 0.05)., Discussion: C2 transpedicular and C1-C2 transarticular screws significantly increased the stabilizing effect compared to sublaminar wiring and lamina hooks. The improved stability afforded by C2 pedicular and C1-C2 transarticular screws offer many potential advantages including a high rate of bony union, early ambulation, and easy nursing care., Conclusion: Occipitocervical reconstruction techniques using C1-C2 transarticular screws or C2 pedicle screws offer biomechanical advantages compared to sublaminar wiring or lamina hooks. Pedicle screw fixation exhibited the highest construct stiffness among the five reconstructions.

Study Design: This static, nondestructive, in vitro biomechanical study examines anterior solid rod construct stiffness following the addition of multilevel, threaded cortical bone dowels in a bovine model. A comparison is made with a clinically relevant posterior construct with and without an anterior release., Objectives: To determine if the addition of solid, multilevel disc space implants will increase construct rigidity, while maintaining or enhancing anterior column length., Summary of Background Data: Anterior instrumentation for thoracolumbar and lumbar scoliosis has achieved greater correction and preserved distal motion segments; however, kyphosis over the instrumented segments and nonunion have been observed more frequently than with posterior segmental spinal instrumentation., Method: Fifteen calf spines underwent mechanical testing. Group A (n = 7) included anterior constructs: 1) intact, 2) anterior release/rod/rib graft (L2-L5), and 3) anterior release/rod/dowels (L2-L5). Group B (n = 8) included posterior constructs: 1) intact, 2) posterior rod without anterior release (T13-L5), 3) posterior rod (T13-L5)/anterior release/rib graft (L2-L5). The protocol included axial compression (-600 N), axial rotation (+7 Nm), flexion/extension (+7.5 Nm), and lateral bending (+7.5 Nm). An anterior extensometer measured segmental displacements to calculate construct stiffness. Lateral radiographs evaluated alignment for the anterior constructs. Statistical analysis involved a one way analysis of variance (ANOVA) and a Student-Newman-Keuls post hoc test., Results: All reconstructions restored stiffness to intact values with the exception of the dowels alone in axial rotation. The rod/dowel construct was stiffer than all other groups in axial compression, flexion/extension, and lateral bending, with the exception of the posterior rod without discectomy, which was superior in flexion and statistically similar in extension, lateral bending, and axial rotation. The anterior construct with rib graft was equivalent to the posterior construct with rib graft in all modes of testing. The dowels created greater lordosis than the bicortical rib grafts., Conclusions: Disc space augmentation increased stiffness except in axial rotation, in which values were restored to the intact level. Stiffness was superior to a clinically relevant posterior instrumentation comparison group following anterior release, and was equivalent to a posterior construct without anterior release except in anterior flexion. In addition, the implants enhanced lordosis. Increased rigidity should improve rates of arthrodesis, while maintenance of sagittal alignment may prevent pathologic compensatory curves in adjacent spinal segments. Further research is required to determine the optimal method of achieving structural interspace support.

Study Design: This is a review of 20 patients who experienced failure of threaded interbody fusion cages and underwent surgical correction., Objective: To review the causes and possible treatment strategies for failed cylindrical cages., Summary of Background Data: Intraoperative complications have been described in the past; however, management of the postoperative patient with failure of interbody fusion devices has not been described., Methods: In 20 patients with failed threaded titanium fusion cages (18 Bagby and Kuslich Devices [BAK; Sulzer-Spine Tech, Minneapolis, MN], 2 Ray Threaded Fusion Cages [Ray TFC; Surgical Dynamics, Norwalk, CT) who underwent revision surgery, all had failure before successful arthrodesis was achieved. Eight of the original titanium cages had been inserted anteriorly (7 laparoscopically), and 12 had been inserted for posterior interbody lumbar fusion. Before the revision surgery, five of the implants were thought to be solid by the referring surgeon, but pseudarthrosis was clearly present in all. In addition, 14 other explanted BAK devices were subjected to undecalcified histologic preparation, quantitative histomorphometry, and histopathologic analysis., Results: The average length of time before revision surgery (implant duration) was 31.8 weeks (range, 1-156 weeks). The most common revision procedure was posterior exploration of the symptomatic nerve root with foraminotomy for unrecognized lateral recess stenosis (11 cases) or excision of iatrogenically herniated intervertebral disc fragments (4 cases). However, four cages inserted through posterior exposure during an interbody lumbar fusion procedure had to be removed because of migration into the spinal canal. In nine cases posterior pedicle screw instrumentation was necessary in addition to posterolateral fusion using iliac crest bone grafting., Conclusions: All 20 cages failed because of surgical technique rather than an intrinsic defect in fusion cage technology. The factors associated with failure of the original insertion procedure were failure to achieve adequate distraction of the anulus fibrosis; undersized cages, especially when placed through the posterior interbody lumbar fusion approach; cerebrospinal fluid leakage or pseudomeningocele; Type 2 diabetes mellitus; the use of local bone graft rather than iliac crest inside the cage; anterior insertion in an excessively lateral position resulting in symptoms of a far lateral disc herniation; and failure to identify the spinal midline during an anterior approach.

Study Design: In an in vivo sheep model, the effects of spinal fusion and kyphotic deformity on the neighboring motion segments were analyzed., Objectives: To investigate the effects of spinal fusion and kyphotic deformity on the adjacent motion segment., Summary of Background Data: The in vivo effects of kyphotic deformity on the neighboring motion segments have not been investigated in any studies., Methods: Eighteen sheep were equally randomized into three groups based on surgical procedure: L3-L5 in situ posterolateral fusion (n = 6) L3-L5 kyphotic posterolateral fusion (n = 6), and surgical exposure alone (n = 6). After a 16-week survival period, the adjacent motion segment changes were analyzed radiographically, biomechanically, and histologically., Results: The kyphosis group showed 5.0 degrees +/- 2.6 degrees and 1.7 degrees +/- 1.8 degrees compensatory hyperlordosis at L2-L3 and L5-L6, respectively, compared with surgical exposure and in situ posterolateral fusion, the kyphotic posterolateral fusion significantly influenced cranial adjacent motion segment biomechanics by inducing more stiffness in the posterior ligamentous complex (P < 0.05) and increasing lamina strain under flexion-extension loading (P < 0.05). Results of histologic analysis showed significant degenerative changes of the L2-L3 facet joints in the kyphosis group., Conclusions: It is inferred that in the kyphosis group, compensatory hyperlordosis at the cranial adjacent level leads to lordotic contracture of the posterior ligamentous complex. The increased lamina strain, exhibited by the in situ group under flexion-extension, was further increased in the kyphosis group, indicating higher load transmission through the posterior column. Significant degenerative changes of the cephalad adjacent facet joints observed in the kyphosis group served to corroborate the biomechanical data. These results indicate that a kyphotic deformity may lead to facet joint contracture and facet arthritis and may serve as the origin of low back pain at the cranial adjacent level.

Human eye bank corneas were preserved in M-K medium for varying periods of time after which viability of the endothelial cells was evaluated by vital staining and scanning and transmission electron microscopy. Endothelial viability and ultrastructural integrity was maintained in some corneas up to four days. Twenty-five consecutive keratoplasties were performed utilizing human donor material stored in M-K medium. There were clear grafts in 92% of the cases and there were no primary graft failures. After the ninth postoperative week, the average central corneal thickness was 0.47 mm and 23 of the 25 grafts remained clear to moderately clear. All of the donor material used for keratoplasty was stored in M-K medium for less than 80 hours.