[Blunt abdominal trauma in children and adolescents: treatment concepts in the acute phase]. / Stumpfes Bauchtrauma bei Kindern und Jugendlichen: Behandlungskonzepte in der Akutphase.

Fatal accidents due to blunt force trauma are the leading cause of death in children and adolescents [1]. Abdominal trauma is the third most common cause of death after traumatic brain injury and thoracic injuries [2]. Abdominal injury is seen in approximately 2-5% of children involved in accidents [3]. Blunt abdominal injuries are common sequelae of traffic accidents (for example as seat belt injury), falls, and sports accidents. Penetrating abdominal injuries are rare in central Europe. Spleen, liver, and kidney lacerations are the most common injuries after blunt abdominal trauma [4]. In most situations, nonoperative management (NOM) has become the gold standard with the surgeon leading the multidisciplinary treatment [5].

Osteogenic lithium-doped brushite cements for bone regeneration.

This study investigated the osteogenic performance of new brushite cements obtained from Li+-doped ß-tricalcium phosphate as a promising strategy for bone regeneration. Lithium (Li+) is a promising trace element to encourage the migration and proliferation of adipose-derived stem cells (hASCs) and the osteogenic differentiation-related gene expression, essential for osteogenesis. In-situ X-ray diffraction (XRD) and in-situ 1H nuclear magnetic resonance (1H NMR) measurements proved the precipitation of brushite, as main phase, and monetite, indicating that Li+ favored the formation of monetite under certain conditions. Li+ was detected in the remaining pore solution in significant amounts after the completion of hydration. Isothermal calorimetry results showed an accelerating effect of Li+, especially for low concentration of the setting retarder (phytic acid). A decrease of initial and final setting times with increasing amount of Li+ was detected and setting times could be well adjusted by varying the setting retarder concentration. The cements presented compressive mechanical strength within the ranges reported for cancellous bone. In vitro assays using hASCs showed normal metabolic and proliferative levels. The immunodetection and gene expression profile of osteogenic-related markers highlight the incorporation of Li+ for increasing the in vivo bone density. The osteogenic potential of Li-doped brushite cements may be recommended for further research on bone defect repair strategies.

Ion-doped Brushite Cements for Bone Regeneration.

Decades of research in orthopaedics has culminated in the quest for formidable yet resorbable biomaterials using bioactive materials. Brushite cements most salient features embrace high biocompatibility, bioresorbability, osteoconductivity, self-setting characteristics, handling, and injectability properties. Such type of materials is also effectively applied as drug delivery systems. However, brushite cements possess limited mechanical strength and fast setting times. By means of incorporating bioactive ions, which are incredibly promising in directing cell fate when incorporated within biomaterials, it can yield biomaterials with superior mechanical properties. Therefore, it is a key to develop fine-tuned regenerative medicine therapeutics. A comprehensive overview of the current accomplishments of ion-doped brushite cements for bone tissue repair and regeneration is provided herein. The role of ionic substitution on the cements physicochemical properties, such as structural, setting time, hydration products, injectability, mechanical behaviour and ion release is discussed. Cell-material interactions, osteogenesis, angiogenesis, and antibacterial activity of the ion-doped cements, as well as its potential use as drug delivery carriers are also presented. STATEMENT OF SIGNIFICANCE: Ion-doped brushite cements have unbolted a new era in orthopaedics with high clinical interest to restore bone defects and facilitate the healing process, owing its outstanding bioresorbability and osteoconductive/osteoinductive features. Ion incorporation expands their application by increasing the osteogenic and neovascularization potential of the materials, as well as their mechanical performance. Recent accomplishments of brushite cements incorporating bioactive ions are overviewed. Focus was placed on the role of ions on the physicochemical and biological properties of the biomaterials, namely their structure, setting time, injectability and handling, mechanical behaviour, ion release and in vivo osteogenesis, angiogenesis and vascularization. Antibacterial activity of the cements and their potential use for delivery of drugs are also highlighted herein.

Acquired von Willebrand syndrome in congenital heart disease surgery: results from an observational case-series.

Essentials Bleeding complications during congenital heart disease surgery in neonatal age are very common. We report the perioperative incidence of acquired von Willebrand syndrome (aVWS) in 12 infants. aVWS was detected in 8 out of 12 neonates and infants intraoperatively after cardiopulmonary bypass. Ten patients received von Willebrand factor concentrate intraoperatively and tolerated it well. SUMMARY: Background Cardiac surgery of the newborn and infant with complex congenital heart disease (CHD) is associated with a high rate of intraoperative bleeding complications. CHD-related anatomic features such as valve stenoses or patent arterial ducts can lead to enhanced shear stress in the blood stream and thus cause acquired von Willebrand syndrome (aVWS). Objective To evaluate the intraoperative incidence and impact of aVWS after cardiopulmonary bypass (CPB) in neonates and infants with complex CHD. Patients/Methods We conducted a survey of patients aged < 12 months undergoing complex cardiac surgery in our tertiary referral center. Twelve patients, whose blood samples were analyzed for aVWS before CPB and immediately after discontinuation of CPB on a routine basis, were eligible for the analysis. von Willebrand factor antigen (VWF:Ag), ristocetin cofactor activity (VWF:RCo), collagen binding activity (VWF:CB), VWF:multimers and factor VIII activity (FVIII:C) were determined. Results aVWS was diagnosed by VWF multimer analysis in 10 out of 12 patients (83%) prior to surgery and intraoperatively at the end of CPB in 8 out of 12 patients (66%). Ten patients received VWF/FVIII concentrate intraoperatively as individual treatment attempts during uncontrolled bleeding. They tolerated it well without intraoperative thrombotic events. One patient suffered a transient postoperative cerebral sinuous vein thrombosis. Conclusions aVWS is of underestimated incidence in complex CHD surgery. These data may offer a new approach to reduce the risk of severe bleedings and to achieve hemostasis during high-risk pediatric cardiac surgery by tailoring the substitution with von Willebrand factor concentrate.

Non-invasive measurement of renal perfusion and oxygen metabolism to predict postoperative acute kidney injury in neonates and infants after cardiopulmonary bypass surgery.

BACKGROUND: The pathophysiology of acute kidney injury (AKI) after cardiopulmonary bypass surgery for congenital heart disease is not completely understood. The aim of this study was to carry out a prospective analysis of the diagnostic value of non-invasive monitoring of renal oxygenation and microcirculation by combining laser Doppler flowmetry and tissue spectrometry. METHODS: In 50 neonates and infants who underwent repair (n = 31) or neonatal palliation (n = 19) of congenital heart disease with cardiopulmonary bypass, renal oxygenation, and microcirculatory flow, the approximate renal metabolic rate of oxygen and Doppler-based renal resistive index were determined after surgery. Correlations between these parameters and the occurrence of AKI according to the Pediatric Risk, Injury, Failure, Loss, End Stage Renal Disease criteria were investigated. RESULTS: Acute kidney injury occurred in 45% of patients after repair and in 32% after palliation. Renal oxygenation was significantly lower and the approximate renal metabolic rate of oxygen significantly higher in patients with AKI (P < 0.05). The microcirculatory flow was significantly higher in patients with AKI after neonatal palliation (P < 0.05), whereas renal resistive index was significantly higher in patients with AKI after repair (P < 0.05). The sensitivity of renal oxygenation, metabolic rate of oxygen, microcirculation, and resistive index in predicting AKI was 78-80, 73-78, 64-83, and 71-74%, respectively, with a specificity of 63-65, 54-75, 64-78, and 46-74% (area under the curve: 0.73-0.75, 0.68-0.83, 0.52-0.68, and 0.60-0.75), respectively. CONCLUSIONS: Monitoring of renal oxygen metabolism allows early prediction of AKI in infants after cardiac surgery. In contrast, renal resistive index does not allow prediction of AKI after neonatal palliation with aortopulmonary shunt establishment.

A new method for determining the insertion depth of tracheal tubes in children: a pilot study.

BACKGROUND: Choosing the correct insertion depth of tracheal tubes is crucial for successful airway management in paediatrics. Currently used formulas are based on patient characteristics such as age, body weight and height. The aim of the study is to devise and evaluate more suitable body surface area based diagrams for predicting the correct tracheal insertion depth. METHODS: Calculated insertion depth according to currently used formulas, primary insertion depth and insertion depth corrected by chest radiography ('gold standard') were collected from 237 children. Age, body weight, height and body surface area were noted. Body surface area based diagrams were devised and prospectively evaluated in another set of 123 paediatric patients. RESULTS: Tracheal tube position according to currently used formulas had to be corrected in 37% of all intubations. New body surface area based diagrams were created. In 20.3%, depth of the tracheal tube had to be corrected according to the new body surface area based diagrams. CONCLUSIONS: The body surface area based diagrams may be a reliable tool for predicting the correct tracheal insertion depth in children.

[Combination of Excessive Weight Gain and Interleukin-8: A Possible Predictor of Necrotising Enterocolitis in Neonates?]. / Kann ein Gewichtssprung in Kombination mit einem Anstieg des Interleukin-8 eine nekrotisierende Enterokolitis bei Neonaten vorhersagen?

BACKGROUND: Weight gain before the clinical diagnosis of necrotising enterocolitis (NEC) is described as a predictive factor. HYPOTHESIS: Weight gain of more than 5% one day prior to clinical suspicion plus increase of plasma Iinterleukin-8 (IL-8) are predictive for NEC. METHODS: 48 infants with diagnosis of NEC stage II and III were enrolled in a case-control study. Oral and parenteral nutrition, diuresis and kinetics of weight and of IL-8 were documented. RESULTS: 31 infants with NEC-II and 17 infants with NEC-III were enrolled. Weight gain>5% occurred in 35.3% of NEC-III, in 0% of NEC-II and in 4.2% of the control group. IL-8 increased significantly [NEC-III (6 561.4 pg/mL) vs. NEC-II: (326.7 pg/mL) vs. control group (38.9 pg/mL); p<0.05]. Sensitivity of IL-8 in NEC-II was 87.10% (70.15-96.25) and in NEC-III 100.00% (80.33-100.00). Sensitivity of weight gain was 0.00% (0.00-11.32) in NEC-II and 35.29% (14.30-61.65) in NEC-III. CONCLUSION: Weight gain>5% was found in only 35.3% of the cases with NEC-III. Combination of weight gain and IL-8 did not improve the diagnosis of NEC.

Diagnostic value of immature myeloid information in early-onset bacterial infection in term and preterm neonates.

BACKGROUND: For quick detection of neonatal early-onset bacterial infection (EOBI) pro-inflammatory cytokines like Interleukin-6 (IL-6) and Interleukin-8 (IL-8) in combiantion with C-reactive Protein (CRP) have been used. Automated determination of immature myeloid information (IMI) seems to be an additional useful tool in the diagnosis of NBI. OBJECTIVE: To compare the diagnostic value of IMI, I/T-Ratio, plasma IL-6 and IL-8 levels and CRP in term and preterm neonates at time of clinical suspicion of EOBI. PATIENTS AND METHODS: 31 preterm and 123 term neonates with clinical and serological signs of EOBI were analysed. 91 preterm and 159 term neonates with risk factors but without proven EOBI served as non-infected controls. RESULTS: Neonates with EOBI showed significantly elevated IMI levels at time of first clinical suspicion of EOBI (Preterm: 1 028/µL (38-8 759) vs. 289/µL (6-3 126); Term: 1 268/µL (48-14 035) vs. 856/µL (19-5 735); p<0.05 respectively). I/T-Ratio, IL-6, IL-8 and CRP values were significantly higher in preterm and term neonates with EOBI (p<0.05). Sensitivity of IMI at a cut-off level of 650/µL was 84.2% [95%-CI: 74.0-91.6%] in preterm and 65.4% [95%-CI: 56.8-73.3%] in term infants. Specificity was 66.7% [95%-CI: 47.1-82.7%] and 53.9% [95%-CI: 43.8-63.7%], respectively. Combination of different infection parameters improved sensitivity up to 93.5% and specificity up to 98.9%. CONCLUSION: The diagnostic value of IMI in diagnosing EOBI in preterm and term neonates is not comparable to IL-6, IL-8 and CRP. Combination of IMI-Channel with IL-6, IL-8 or CRP improves their sensitivity, specificity and predictive value.

Safety, efficacy and response to a hydrocortisone rescue therapy protocol in children with refractory hypotension after cardiopulmonal bypass.

Little is known about which paediatric patients respond to hydrocortisone rescue therapy (HRT) with improvement of haemodynamic stability in refractory hypotension after cardiopulmonal bypass. Data were gathered retrospectively from children who received HRT in refractory hypotension after cardiopulmonary bypass in the period from 2000 to 2010. One hundred and sixty-six out of 1,273 children, 150 <1 year and 16 >1 year were enrolled. HRT improved haemodynamics significantly, increased blood pressure, decreased the vasoactive-inotropic score and plasma lactate concentrations in all children >1 year and in 82 % (123 out of 150) of the infants <1 year. Non-responders <1 year were significantly younger, lighter, mostly male infants and had longer cardiopulmonary bypass support time. Serum lactate and paediatric risk of mortality score were significantly higher in non-responders at time of initiation of HRT. Mortality was significantly higher in non-responders versus responders (2.44 vs. 13.5 %; p = 0.0008). HRT caused no adverse effects like electrolyte disturbances or hyperglycaemia. HRT in refractory hypotension after paediatric cardiac surgery is safe but not all infants <1 year show haemodynamic response to HRT. Non-response to HRT is associated with significantly higher mortality.

Diagnostic value of an interleukin-6 bedside test in term and preterm neonates at the time of clinical suspicion of early- and late-onset bacterial infection.

BACKGROUND: For quick detection or exclusion of neonatal early-onset bacterial infection (EOBI) or late-onset bacterial infection (LOBI), interleukin (IL)-6 is used. Its clinical use is sometimes limited due to prolonged recall times. Therefore, an IL-6 bedside test was established. OBJECTIVE: To compare the diagnostic value of plasma IL-6 and an IL-6 bedside test at the time of clinical suspicion in the course of EOBI and LOBI. METHODS: Eighteen term (mean gestational age 40.2 weeks, SD 1.3) and 88 preterm (mean gestational age 30.1 weeks, SD 4.2) neonates with clinical and serological signs of bacterial infection were analysed. Eight had an EOBI, and 24 had a LOBI, of whom 13 were blood culture positive. Twelve term and 62 preterm neonates with risk factors but without proven EOBI/LOBI served as a non-infected group. RESULTS: At the time of clinical suspicion, the sensitivity of the IL-6 bedside test in comparison to plasma IL-6 was 69 versus 75% (p = 0.7744, McNemar's test), and specificity was 77 versus 81% (p = 0.6476, McNemar's test; cutoff level 50 ng/l). For LOBI, both the sensitivity (75%) and specificity (82%) of the bedside test exceeded values calculated for EOBI (sensitivity 50%, specificity 75%). CONCLUSION: No significant difference between the bedside and established plasma IL-6 test was detected for LOBI. For detection of EOBI, the bedside test was not sensitive enough. Larger studies are needed to verify our findings before IL-6 bedside tests can be recommended routinely.

[Neonatal intracerebral bleeding as initial symptom of gliomatosis cerebri WHO III--neurological outcome after partial hemispherectomy]. / Eine neonatale intrazerebrale Blutung als Initialsymptom einer Gliomatosis cerebri WHO III--neurologisches Outcome nach partieller Hemisphärektomie.

INTRODUCTION: Anaplastic astrocytomas presenting as gliomatosis cerebri in neonates are extremely rare. Tumours in newborns are mostly of neuroectodermal origin. CASE REPORT: We report about a female newborn at term [birth weight 3 600 g (P 90), head circumference 35 cm (P 95) APGAR 9/10/10] with an intracerebral partially clotted bleeding in the left parieto-occipital region. The bleeding was expansive leading to axial and lateral cerebral herniation. The intracerebral bleeding in the left occipital region was surgically removed. Macroscopically no solid tumour was seen, but small fragments of an anaplastic astrocytic tumour (WHO grade III) were diagnosed histologically. After surgery, no remaining tumour was visible in the MRI. 6 weeks later, a recurrent tumour (4×4 cm) was found in the area of the initial bleeding. Further treatment was initially refused by the parents. The child was readmitted to our hospital at the age of 11 months in good clinical condition and presented with left-sided hemiparesis, right-sided hemianopsia and intermittent strabismus convergens alternans. Because of the good clinical condition further therapeutic treatment was initiated. Due to the final extension of the tumour into the temporal, parietal and occipital lobes, a gliomatosis cerebri WHO III was diagnosed. An extended partial hemispherectomy was done. After neurosurgery, no further neurological failures occurred. In the follow-up examination, MRI showed no relapse of the tumour. Chemotherapy according to the HIT SKK protocol was initiated. A relapse did not occur over a follow-up of 2 years. CONCLUSION: This is a rare case report of a congenital gliomatosis cerebri WHO grade III, treated with partial hemispherectomy, leading to a good clinical and neurological long-term outcome.

In vitro performance assessment of new brushite-forming Zn- and ZnSr-substituted beta-TCP bone cements.

The present study investigated the in vitro performance of brushite-forming Zn- and ZnSr-substituted beta-TCP bone cements in terms of wet mechanical strength and biological response. Quantitative phase analysis and structural refinement of the powdered samples were performed by X-ray powder diffraction and Rietveld refinement technique. Initial and final setting times of the cement pastes, measured using Gilmore needles technique, showed that ZnSrCPC sets faster than ZnCPC. The measured values of the wet strength after 48 h of immersion in PBS solution at 37 degrees C showed that ZnSrCPC cements are stronger than ZnCPC cements. Human osteosarcoma-derived MG63 cell line proved the nontoxicity of the cement powders, using the resazurin metabolic assay.

Synthesis and structural characterization of strontium- and magnesium-co-substituted beta-tricalcium phosphate.

The synthesis of five different Sr(2+)- and Mg(2+)-co-substituted beta-tricalcium phosphate (beta-TCP) has been obtained by heating the calcium-deficient apatites above 800 degrees C. With the investigated concentrations of Sr(2+) and Mg(2+) from the present study, no additional phases other than beta-TCP have been detected. The synthesized powders have been characterized by X-ray diffraction, Fourier transform infrared spectrometry, elemental analysis and Rietveld refinement studies. The co-substitution of Sr(2+) and Mg(2+) in the beta-TCP has resulted in the formation of crystalline beta-TCP at hexagonal setting (space group R3c). The reduction of lattice a- and c-axis parameters with the combined substitution of Sr(2+) and Mg(2+) in the beta-TCP has been found evident from the present results. Sr(2+) has been found occupying the Ca(1,2,3,4) sites and Mg(2+) was found at the sixfold coordinated Ca(5) site of beta-TCP structure.

Newly developed Sr-substituted alpha-TCP bone cements.

New bone cements made of Sr-substituted brushite-forming alpha-tricalcium phosphate (alpha-TCP) were prepared and characterized in the present work. The quantitative phase analysis and structural refinement of the starting powders and of hardened cements were performed by X-ray powder diffraction and the Rietveld refinement technique. Isothermal calorimetry along with setting time analysis allowed a precise tracing of the setting process of the pastes. The pastes showed exothermic reactions within the first 10-15 min after mixing and further release of heat after about 1h. An apatitic phase formed upon immersion of the hardened cements in simulated body fluid for 15 and 30 days due to the conversion of brushite into apatite confirming their in vitro mineralization capability. The compressive strength of the wet cement specimens decreased with increasing curing time, being higher in the case of Sr-substituted CPC. The results suggest that the newly developed Sr-substituted brushite-forming alpha-TCP cements show promise for uses in orthopaedic and trauma surgery such as in filling bone defects.

[Biventricular hypertrophic non-obstructive cardiomyopathy as a symptom of transient myeloproliferative disorder in a newborn with Down syndrome]. / Eine biventrikuläre hypertrophe Kardiomyopathie als Initialsymptom eines transitorisch myeloproliferativen Syndroms bei einem Neugeborenen mit Down Syndrom.

Down's syndrome is the most frequent autosomale chromosomal anomaly in newborns. In up to 10% of the cases these children develop a transient myeloproliferative disorder (TMD). Clinical symptoms are blood count disorders and raised liver enzymes. 15% of these neonates suffer from hepatic disorders. Complications can lead to effusions, liver fibrosis and multiple organ failure. In 20-30% of these cases the children develop subsequently acute myeloid leukemia. We report about a male, term newborn [birth weight 2 810 g (P10), length 49 cm (P30), head circumferance 35 cm (P50), APGAR 7/8/10] with hydrops fetalis. In the follow-up examination a pericardial effusion and increasing biventricular hypertrophic cardiomyopathy were obvious. A chemotherapy with cytarabine was initiated for five days. In further examinations cardiac recovery was observed. To the best of our knowledge this is the first case report of a term newborn with TMD and biventricular hypertrophic cardiomyopathy.

Rietveld structure and in vitro analysis on the influence of magnesium in biphasic (hydroxyapatite and beta-tricalcium phosphate) mixtures.

The structure of two different Mg-substituted biphasic (HAP and beta-TCP) mixtures along with the biphasic mixtures without substituted Mg(2+) was investigated using Rietveld refinement technique. The substituted Mg(2+) was found in the beta-TCP phase and its influence on the composition has led to an increase in HAP content of Mg-containing biphasic mixtures when compared with the HAP content detected in pure biphasic mixtures. The refined structural parameters of Ca(10)(PO(4))(6)(OH)(2) and beta-Ca(3)(PO(4))(2) confirmed that all the investigated compositions have crystallized in the corresponding hexagonal (space group P6(3)/m) and rhombohedral (space group R3c) structures. The substitution of lower sized magnesium was found preferentially incorporated at the sixfold-coordinated Ca (5) site of beta-TCP, which is due to the strong Ca (5).O interaction among all the five different Ca sites of beta-Ca(3)(PO(4))(2). The in vitro tests using primary culture of osteoblasts showed that all the tested samples are biocompatible and promising materials for in vivo studies.

[Intracerebral bleeding as the first symptom of a congenital anaplastic astrocytoma]. / Eine intrazerebrale Blutung als Initialsymptom eines konnatalen anaplastischen Astrozytoms.

BACKGROUND: Anaplastic astrocytomas in neonates are extremely rare. Newborns, however, often have neuroectodermal central nervous tumours. CASE REPORT: We report about a female term newborn (birth weight 3,600 g, APGAR 9/10/10), who had shrill screams, intermittent shivering and bradycardia. An ultrasound scan of the brain showed an intracerebral bleeding. Therefore, the child was transferred to the intensive care unit of our hospital. A CT scan showed cerebral bleeding in the left parieto-occipital region, partially clotted, with a space-demanding effect. The intracerebral bleeding in the left occipital region was cleared out. No tumour was found, but an anaplastic astrocytoma (WHO Grade III) was diagnosed histologically. Serial ultrasound investigations of the brain showed a normal midline and a redevelopment of the left-sided ventricle. After surgery no tumour was visible in the MRI. Six weeks later, a tumour was found in the area of the initial bleeding region on MRI. CONCLUSION: Congenital anaplastic astrocytomas have a variable outcome, with different survival rates as compared to adults. In the literature, survival rates of 36-50 % were found after complete tumour resection. In cases of neonatal intracerebral bleeding, a tumour might be the cause of the haemorrhage.

Lipopolysaccharide-binding protein in noninfected neonates and those with suspected early-onset bacterial infection.

OBJECTIVES: To investigate postnatal lipopolysaccharide-binding protein (LBP) kinetics in term neonates and to test its diagnostic accuracy for early-onset bacterial infection (EOBI). STUDY DESIGN: A total of 99 neonates with clinical and serological signs of EOBI comprised the study group; 198 neonates with risk factors, but without EOBI, served as controls. LBP, C-reactive protein (CRP) and interleukin-8 (IL-8) were determined. RESULTS: LBP in the noninfected group increased until 24 h after birth (P < 0.05 vs 6 h). LBP and CRP correlated strongly in neonates with suspected EOBI (r = 0.63). Although LBP reached a higher sensitivity than CRP 6 and 12 h after clinical suspicion (45 (24-68) and 79% (54-94) vs 9 (0-24) and 39% (17-64); P < 0.05)), EOBI was most reliably detected by IL-8. CONCLUSION: LBP kinetics were age-dependent. LBP was not sufficiently sensitive in the prediction of EOBI.

Influence of magnesium doping on the phase transformation temperature of beta-TCP ceramics examined by Rietveld refinement.

The influence of Mg doping in Ca(3)(PO(4))(2) on the transformation temperature of beta-tricalcium phosphate (beta-TCP) to alpha-tricalcium phosphate (alpha-TCP) was examined. A maximum substitution by 14 mol% of Mg(2+) on Ca(2+) sites in the beta-TCP structure was determined for powders calcinated at 1025+/-10 degrees C. X-ray powder diffraction analysis (XRPD) in combination with Rietveld method (TOPAS 2.1) was employed for quantitative phase analysis and structural refinement. The synthesized and characterized Mg-doped samples were sintered in air atmosphere in a vertical tube furnace at suitable temperatures ranging from 1460 to 1680 degrees C and subsequently quenched to room temperature, in order to stabilize alpha-TCP. The beta to alpha transformation temperatures were determined by differential temperature analysis and XRPD analysis.