The effect of different forms of heparin on point-of-care blood gas analysis.

BACKGROUND: Point-of-care blood gas analysis plays an integral role in the management of critically ill and injured patients presenting to the emergency department (ED). While the use of specially manufactured syringes containing electrolyte-balanced dried heparin is recommended when processing these specimens, alternatives including manually self-prepared syringes washed with liquid heparin or heparin vacutainers are still often used. OBJECTIVES: To assess the effect of two concentrations of liquid heparin and the use of heparin vacutainers on the reliability of blood gas analysis results compared with the recommended standard of dried heparin syringes in the ED setting. METHODS: Blood samples were drawn from 54 patients attending a tertiary-level hospital ED. Individual samples were distributed equally among each of four different collection devices: a dried heparin syringe, self-prepared syringes washed separately with 1 000 IU/mL and 5 000 IU/mL liquid heparin, and a heparin vacutainer. Results obtained from the standard dried heparin syringes were compared with those from the other three methods. RESULTS: For both the liquid heparin cohorts, partial pressure of carbon dioxide (pCO2), potassium (K+), sodium (Na+), ionised calcium (iCa2+) and haemoglobin had >20% of results falling beyond the total allowable error. iCa2+ and K+ results were most affected in the 5 000 IU/mL cohort and iCa2+ and Na+ in the 1 000 IU/ml cohort. pCO2, pH and iCa2+ were the most significantly affected in the heparin vacutainer cohort. CONCLUSIONS: Use of liquid heparin can result in significant negative bias in the majority of blood gas analytes, especially electrolytes. Heparin vacutainer use can result in unacceptable variations in the respiratory analytes. While standard dried heparin syringes may not always be available, it is of vital importance that practitioners be aware of these biases and limitations when using substitutes.

Early Class II treatment.

The treatment of children presenting with a Class II division I malocclusion involves one of two approaches. The first provides treatment in two phases; one of intervention during the mixed dentition (phase I) followed by a second definitive course of appliance treatment in early adolescence (phase II). The second approach involves providing a single course of comprehensive therapy during adolescence. The debate for and against early treatment is discussed alongside key, clinically relevant evidence related to Class II division I malocclusions.

Advances in orthodontic anchorage with the use of mini-implant techniques.

Orthodontic mini-implants (OMIs) represent a new form of anchorage provision and appear to provide a variety of benefits for both anchorage-demanding and complex orthodontic cases. This paper reports the latest perspectives on OMIs in terms of the emerging clinical evidence base coupled with their varied clinical applications.

Maxillary labial fraenectomy: indications and technique.

UNLABELLED: A labial fraenectomy is indicated in various clinical situations and is performed to facilitate orthodontic closure of a maxillary midline diastema. In these clinical situations, timing of surgery during the phase of orthodontic treatment is important. Labial fraenectomy can be performed before, during or after the orthodontic closure of the maxillary midline diastema, depending on the individual case. It is important to understand how to perform the procedure efficiently and effectively. Success relies as much on accurate diagnosis of the fleshy, prominent or persistent fraenum as it does on meticulous technique to ensure its complete elimination. This article presents the indications for labial fraenectomy. The appropriate timing of the labial fraenectomy procedure to facilitate orthodontic treatment is discussed. CLINICAL RELEVANCE: A surgical technique to perform maxillary labial fraenectomy procedure in an effective and efficient manner is a useful addition to the clinician's armamentarium.

Midpalatal implants vs headgear for orthodontic anchorage--a randomized clinical trial: cephalometric results.

INTRODUCTION: The purpose of this study was to compare the clinical effectiveness of the midpalatal implant as a method of reinforcing anchorage during orthodontic treatment with that of conventional extraoral anchorage. This was a prospective, randomized, clinical trial at Chesterfield and North Derbyshire Royal Hospital NHS Trust and the Charles Clifford Dental Hospital, Sheffield, in the United Kingdom. METHODS: Fifty-one orthodontic patients between the ages of 12 and 39, with Class II Division 1 malocclusion and absolute anchorage requirements, were randomly allocated to receive either a midpalatal implant or headgear to reinforce orthodontic anchorage. The main outcome was to compare the mesial movement of the molars and the incisors of the 2 treatment groups between the start and the end of anchorage reinforcement as measured from cephalometric radiographs. RESULTS: The reproducibility of the measuring technique was acceptable. There were significant differences between T1 and T2 in the implant group for the positions of the maxillary central incisor (P <.001), the maxillary molar (P = .009), and the mandibular molar (P <.001). There were significant differences between T1 and T2 in the headgear group for the positions of the mandibular central incisor (P <.045), the maxillary molar (P <.001), and the mandibular molar (P <.001). All skeletal and dental points moved mesially more in the headgear group during treatment than in the implant group. These ranged from an average of 0.5 mm more mesially for the mandibular permanent molar to 1.5 mm more mesially for the maxillary molar and the mandibular base. No treatment changes between the groups were statistically significant. CONCLUSIONS: Midpalatal implants are an acceptable technique for reinforcing anchorage in orthodontic patients.

How to ... place a lower bonded retainer.

Post-orthodontic relapse of lower incisors is a common phenomenon. Sometimes a bonded retainer is fitted to prevent this relapse. In this article, we suggest a handy clinical technique of fitting a lower bonded retainer, which is convenient and easy to carry out.

How to avoid common errors in clinical photography.

This paper demonstrates some of the errors commonly seen in both conventional and digital photography when used for clinical purposes, and details how some of these mistakes may be avoided.

How to effectively use a 2 x 4 appliance.

A mixed dentition treatment can efficiently and effectively be provided using a 2 x 4 appliance. The indications for early treatment are discussed and advantages of fixed appliances over traditionally used removable appliances illustrated using four case reports.

Keeping your eye on the ball.

Dentigerous cysts develop from unerupted and impacted permanent teeth. Very rarely, supernumerary teeth are associated with dentigerous cysts and constitute about 5-6% of all dentigerous cysts. Although these cysts are not common in the first decade of life, regular thorough inspection of radiographs is of importance, as indicated by this case report. This case shows how an impacted supernumerary canine developed a dentigerous cyst, engulfing the whole of the maxillary antrum.

The potentially fatal vascular anomaly and orthodontic treatment--a case report.

Oral vascular lesions are of clinical importance to the dental profession because they pose serious bleeding risks. A case report is presented here where a patient with a complex palatal vascular malformation was successfully treated with fixed appliances. The problems encountered during treatment are discussed.

Autotransplantation of an impacted third molar: an orthodontic case report.

This case report describes the use of autotransplantation as part of an orthodontic treatment plan where there was early loss of an upper molar tooth secondary to irreversible pulpitis. An impacted lower third molar, which had symptoms of pericoronitis, was transplanted into the upper left second molar socket. Fixed orthodontic treatment, to correct the patient's initial complaint of crowding, was completed in 22 months. The transplanted tooth remained vital and functional throughout.

European Board of Orthodontists: a professional challenge.

The background to the formation of the European Board is given and the necessary procedures for obtaining certification of the European Board of Orthodontists (EBO) are described. An example case report is included to give the reader an indication of the type of detail required for each and every case presented. Recommendations are given for prospective candidates who might consider attempting EBO certification in the future.

A randomized clinical trial to compare the effectiveness of canine lacebacks with reference to canine tip.

AIM: To assess the effectiveness of canine lacebacks on the proclination of the upper incisors with reference to pre-treatment canine tip. STUDY DESIGN: Randomized clinical trial. SAMPLE: Patients receiving upper and lower fixed appliances attending the orthodontic departments of five orthodontic treatment providers. Sixteen patients received canine lacebacks as part of their treatment and 19 patients did not have canine lacebacks. METHOD: Patients were randomly allocated to receive canine lacebacks or not receive canine lacebacks. Upper study models were collected at the initial archwire placement and then when the working 0.019 x 0.025-inch stainless steel archwire was placed. The start canine angulation, change in upper incisor proclination/overjet, and any mesial movement of the upper first permanent molars during levelling and aligning was measured with a reflex metrograph. STATISTICS: The effect of the use of canine lacebacks on upper incisor proclination and mesial molar movement was assessed using Student t-tests. Regression analysis was used to evaluate any effect of the initial angulation of the canine. RESULTS: A mean incisor retroclination of 0.5 mm was observed in the canine lacebacks compared with a mean proclination of 0.36 mm when canine lacebacks were not used (P = 0.025). There was no statistically significant difference between groups for mesial movement of upper first molars (P = 0.99). If the canine was more distally inclined at the start of treatment, the incisors was more likely to procline, regardless of whether or not canine lacebacks were used (P = 0.027). CONCLUSIONS: The effect of canine lacebacks on preventing upper incisor proclination at the start of treatment is in the order of 1 mm and their effect on mesial molar movement is insignificant. Canines lacebacks have similar effects that are independent of pre-treatment canine angulation.

Rapid correction of anterior crossbite using a fixed appliance: a case report.

Anterior crossbite is a commonly encountered problem that is traditionally managed with removable appliances. This paper demonstrates some of the advantages of using fixed appliances to correct these malocclusions. In this case, treatment was completed more rapidly than would have occurred with conventional techniques.

Digital records in orthodontics.

In this electronic age there is a general move towards keeping digital records, and many trades and professions now use digital images exclusively. In this article, the advantages (and occasional disadvantages) of the use of digital photography, digital radiography and the latest development--digital study models--in orthodontics are discussed.

The modified twin block appliance in the treatment of Class II division 2 malocclusions.

Two case reports illustrate the effective treatment of Class II division 2 malocclusion with modifications to the Twin Block appliance. This approach may reduce the total treatment time and reduce the need for extra-oral anchorage. In each of the cases presented treatment has been carried out on a non-extraction basis with full correction of the malocclusion.

Comparison of 2 modifications of the twin-block appliance in matched Class II samples.

The purpose of this study was to compare the skeletal and dental changes contributing to Class II correction with 2 modifications of the Twin-block appliance: Twin-block appliances that use a labial bow (TB1) and Twin-block appliances that incorporate high-pull headgear and torquing spurs on the maxillary central incisors (TB2). After pretreatment equivalence was established, a total of 36 consecutively treated patients with the TB1 modification were compared with 27 patients treated with the TB2 modification. Both samples were treated in the same hospital department and the same technician made all the appliances. The cephalostat, digitizing package, and statistical methods were common to both groups. The results demonstrated that the addition of headgear to the appliance resulted in effective vertical and sagittal control of the maxillary complex and thus maximized the Class II skeletal correction in the TB2 sample. Use of the torquing springs resulted in less retroclination of the maxillary incisors in the TB2 sample when compared with the TB1 sample; however, this difference did not reach the level of statistical significance.