Adverse effects of orthodontic treatments

Orthodontic therapy, like any other medical intervention, in addition to its benefits carries the risk of potential complications and is associated with adverse effects-including periodontal problems, external root resorptions, pulpal changes, enamel damages (demineralization, discoloration, attrition), temporomandibular disorders, infective endocarditis, soft tissue damages, discomfort, pain and the risk of either aspiration or indigestion of medical instruments and appliances. Usually these effects are multifactorial in origin- most often a result of interactions between the patient, the dental practitioner and the technical aspects of the appliances or techniques. With preventive measurements and care, most of these complications can be either limited or completely avoided. Therefore, every dental practitioner must be fully aware of these effects and associated risk factors in order to maximize the treatment outcome. The present review aims to summarize these effects of orthodontic therapies, and provide a detailed description of factors and preventive measures, in order to minimize these damages.

Recent Developments and Controversies in the Treatment of Resistant Hypertension

Resistant hypertension is defined as elevated blood pressure despite the appropriate use of 3 or more antihypertensive drugs, including a diuretic, and constitutes a frequent and important clinical problem with significant disease morbidity and mortality. Several sources of evidence point to the sympathetic nervous system as a major protagonist in this disease entity. The catheter-based, radiofrequency ablation of renal sympathetic nerves (renal denervation) to treat resistant hypertension has sparked great enthusiasm. However, failure of this interventional approach in the randomized, sham-controlled Symplicity HTN-3 trial to reach its efficacy endpoint of attaining a significant blood pressure reduction has called this intervention into substantial question and fueled an ongoing scientific debate. Electrical stimulation of the carotid baroreceptors (baroreflex activation therapy) represents another technique to modulate sympathetic activity currently being studied in several clinical trials. This review summarizes and comments the current literature focusing on the invasive treatment of resistant hypertension.

[Interventional mitral valve replacement. Current status]

Approximately 30 % of patients suffering from severe valvular heart disease, such as mitral valve regurgitation are non-compliant to the gold standard of minimally invasive surgery, reconstruction or valve replacement. The number of these mostly old patients with severe comorbidities is increasing; therefore, transcatheter interventions have been developed to address an unmet clinical need and may be an alternative therapeutic option to the reference standard. Apart from the successful MitraClip therapy, alternative transcatheter reconstruction technologies are being developed. As with transcatheter aortic valve implantation (TAVI) procedures, the off-pump implantation of a valved stent into the mitral position mainly via a transapical approach will be of great benefit. Recently, the feasibility of transcatheter mitral valved stent implantation in high-risk patients has already been reported.

Fistulizing Epstein-Barr virus-positive plasmablastic lymphoma in an HIV-positive man

Plasmablastic lymphoma (PBL) is an unusual subtype of non-Hodgkin lymphoma recently classified as a diffuse immunoblastic lymphoma with a plasma-cell immunophenotype. Originally described in the oral cavity of HIV-positive patients, it has also been recognized to occur rarely at other sites. We describe a previously unreported fistulizing presentation of Epstein-Barr virus (EBV)-positive PBL, reviewing its association with HIV-1 infection and its importance as an AIDS-defining malignancy.

[Distal soft-tissue procedure in hallux valgus deformity]

OBJECTIVE

Distal, lateral soft tissue release to restore mediolateral balance of the first metatarsophalangeal (MTP) joint in hallux valgus deformity. Incision of the adductor hallucis tendon from the fibular sesamoid, the lateral capsule, the lateral collateral ligament, and the lateral metatarsosesamoid ligament.

INDICATIONS

Hallux valgus deformities or recurrent hallux valgus deformities with an incongruent MTP joint.

CONTRAINDICATIONS

General medical contraindications to surgical interventions. Painful stiffness of the MTP joint, osteonecrosis, congruent joint. Relative contraindications: connective tissue diseases (Marfan syndrome, Ehler-Danlos syndrome).

SURGICAL TECHNIQUE

Longitudinal, dorsal incision in the first intermetatarsal web space between the first and second MTP joint. Blunt dissection and identification of the adductor hallucis tendon. Release of the adductor tendon from the fibular sesamoid. Incision of the lateral capsule, the lateral collateral ligament, and the lateral metatarsosesamoid ligament.

POSTOPERATIVE MANAGEMENT

Postoperative management depends on bony correction. In joint-preserving procedures, dressing for 3 weeks in corrected position. Subsequently hallux valgus orthosis at night and a toe spreader for a further 3 months. Passive mobilization of the first MTP joint. Postoperative weight-bearing according to the osteotomy.

RESULTS

A total of 31 patients with isolated hallux valgus deformity underwent surgery with a Chevron and Akin osteotomy and a distal medial and lateral soft tissue balancing. The mean preoperative intermetatarsal (IMA) angle was 12.3° (range 11-15°); the hallux valgus (HV) angle was 28.2° (25-36°). The mean follow-up was 16.4 months (range 12-22 months). The mean postoperative IMA correction ranged between 2 and 7° (mean 5.2°); the mean HV correction was 15.5° (range 9-21°). In all, 29 patients (93%) were satisfied or very satisfied with the postoperative outcome, while 2 patients (7%) were not satisfied due to one delayed wound healing and one recurrent hallux valgus deformity. There were no infections, clinical and radiological signs of avascular necrosis of the metatarsal head, overcorrection with hallux varus deformity, or significant stiffness of the first MTP joint.

Transapical mitral valve implantation: the Lutter valve

  The development of transcatheter techniques for treatment of severe mitral valve regurgitation in the beating heart is focus of recent research. An off-pump treatment technique poses great benefits, particularly for multimorbid patients, often being non-compliant to the gold standard treatment, being open heart surgery with use of a cardiopulmonary bypass. Thereto, two approaches are being followed: transcatheter valve repair and transcatheterimplantation of a valved stent into the native mitral valve annulus. A valved stent has to provide safe and secure fixation within the high pressure system of the left heart. One of the main challenges in the development of such a valved stent is the complex anatomy of the mitral valve, with no clearly defined structures for device anchorage. Our group has developed a self-expanding nitinolvalved stent for transapical implantation in the beating heart. During the development process of thevalved stent, different design iterations were conducted to decrease the risk of paravalvular leakages, to enhance the reproducibility and to improve the overall stent performance. This article reviews the major milestones passedin the development process of our mitral valved stent and advances achieved withinthe last years. Multiple design iterations lead to a prototype providing secure stent deployment, hig h reproducibility, low paravalvular leakages and only mild stent deformation in the beating heart. In future, further long-term in vivo trials have to be conducted before attempting the step towards clinical application of this novel device.

[A case of venlafaxine-induced syndrome of inappropriate ADH secretion (SIADH) - treatment with tolvaptan]

HISTORY AND ADMISSION FINDINGS

A 74-year-old woman with known COPD was admitted to hospital because of dyspnoa. Clinical and laboratory tests showed an acute pulmonary infection which was treated with antibiotics. Additionally she was found to have a moderately severe episode of depression for which she had the preceding three weeks been treated with venlafaxine, a selective serotonin re-uptake inhibitor. During the subsequent days she gradually developed a hyponatremia with serum sodium levels down to 108 mmol/l.

INVESTIGATIONS

After excluding common causes of hyponatremia such as a cerebral or pulmonal malignancy or endocrine disorders by computed thomography and laboratory tests, a venlafaxine induced syndrome of inappropriate ADH secretion (SIADH) was assumed to be the cause of the hyponatremia.

TREATMENT AND COURSE

As neither discontinuation of venlafaxine nor strict fluid restriction led to a rise in the natrium level and the patient had a generalized seizure, oral treatment with the tolavaptan, a vasopressin-2-receptor antagonist, was initiated. This resulted within 48 hours in a rise of the sodium level to 131 mmol/l and there were no further seizures.

CONCLUSION

Hyponatremia is a relatively common side effect of medical treatment with SSRI or SSNRI in elderly patients. The therapy of choice in case of a hyponatremia due to a SIADH is to discontinue the antidepressive drugs and institute strict fluid restriction. Tolvaptan has recently emerged as a promising new therapeutic option for SIADH.

[A special soft tissue procedure for treatment of hallux valgus]

OBJECTIVE

Maintaining the corrected position of the first metatasophalangeal axis. Reducing postoperative stiffness by forgoing a medial capsular shift.

INDICATIONS

Hallux valgus deformities or recurrent hallux valgus deformities.

CONTRAINDICATIONS

Existing osteoarthritis, joint stiffness, large bone defects, osteonecrosis. General medical contraindications to surgical interventions and anesthesiological procedures.

SURGICAL TECHNIQUE

Operation under regional anesthesia (foot block) or general anesthesia. Tourniquet. Longitudinal skin incision medial over the pseudexostosis of the first metatarsal bone. Preparing the tendon of the Musculus abductor hallucis. Detaching the tendon from the capsule. Incision of the joint capsule with protection of the extensor hallucis longus tendon and the dorsal neurovascular bundle in an L-wise manner. Osteotomy of the first metatarsal bone. Lax sutures of the capsule in correct position and reattachment of the Musculus abductor hallucis tendon shifted toward distal and dorsal, regarding the rotation of the hallux.

POSTOPERATIVE MANAGEMENT

Postoperative elevation of the operated foot. Analgesia with nonsteroidal antiinflammatory drugs. Postoperative weight-bearing according to the osteotomy. Passive mobilization of the metatarsophalangeal joint. Dressing for 4 weeks postoperatively in the corrected position. Radiologic control after 6 weeks. Hallux valgus orthosis at night and a toe spreader for a further 6 weeks.

RESULTS

A total of 30 isolated hallux valgus deformities with a mean preoperative intermetatarsal (IMA) angle of 12.9° (range 11-15°) were operated with a chevron osteotomy. The mean follow-up was 14.4 (range 8-17) months. The mean dorsiflexion at the last follow-up was 44° (range 20-60°). Only 2 patients had a dorsiflexion <40°. The mean reduction of the IM angle was 5.6° (range 3-7°). One patient required wound revision. There was no infection or avascular necrosis of the metatarsal head observed in the patients. At follow-up, 20 (67%) patients were completely satisfied, 9 (30%) satisfied, and 1 (3%) was not satisfied.