The value of three-dimensional imaging in the detection of a case of double pathology in the right maxilla of a patient.

A 14-year-old Black female was referred for management of an asymptomatic swelling in her right maxilla. The lesion measured 3cm across, was localised lateral to the right ala of the nose, felt bony hard in some areas and soft in others, and was continuous with the maxillary buccal plate. It occupied the right anterior vestibule but there was no palatal expansion. A panoramic radiograph showed a radiopaque lesion surrounded by a radiolucent periphery, but a lack of clarity prompted a computed tomographic scan. The latter revealed two separate lesions, one buccal and one palatal. The buccal lesion showed a well-defined radiolucency containing a radiopaque mass while the palatal lesion showed a small cystic area attached to the neck of an impacted tooth. Differential diagnoses of calcifying odontogenic cyst, adenomatoid odontogenic tumour or ameloblastic fibroodontoma and dentigerous cyst or odontogenic keratocyst were considered for the two lesions respectively. Enucleation of the buccal lesion and removal of the impacted tooth together with the overlying cyst presented no problem. Histologically the lesions were respectively diagnosed as a calcifying odontogenic cyst and a dentigerous cyst. Histological features are briefly described together with an historical review of the calcifying odontogenic cyst which has evoked much interest and controversy over the past five decades.

Plunging ranula: an unusual multilocular presentation.

A 32-year-old male patient who was HIV positive presented at the Wits Oral Health Centre complaining of a large swelling of the left submandibular region of three years' duration. The swelling was nontender, soft and doughy on palpation and appeared to be crossing the midline. Bilateral submandibular and submental lymphadenopathy was present. Intraorally the lesion caused considerable elevation of the floor of the mouth and impaired the flow of saliva. Fluid from the lesion was aspirated and the patient sent for MRI examination. These images revealed a multilocular cystic lesion causing disruption of the mylohyold muscle. The aspirate consisted of a thick, bloody fluid which tested positive for salivary amylase. A provisional diagnosis of plunging ranula was made. The multilocular nature of the lesion seen on MRI prompted a more extensive surgical approach in order to prevent recurrence. Consequently the sublingual gland was removed via an intraoral approach while the multilocular cyst was dissected by means of a submandibular approach in order to effect complete removal. Microscopic examination of the submitted specimen confirmed the clinical diagnosis of a plunging ranula.

Effects of light intensity and temperature on Cylindrospermopsis raciborskii (Cyanobacteria) with straight and coiled trichomes: growth rate and morphology.

Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju (Ordem Nostocales) is one of the most troublesome bloom-forming species in Brazil. Understanding the population dynamics of the different morphotypes of C. raciborskii (straight and coiled) could assist in the prediction of favourable conditions for the proliferation of this potentially toxin-producing species. The aim of the present study was to assess the effects of two different light intensities and temperatures on the growth rate and morphology of the trichomes of the straight and coiled morphotypes. For such, two non-toxin producing strains of C. raciborskii were used - one with a coiled trichome (ITEP31) and another with a straight trichome (ITEP28). The strains were cultured in BG-11 medium in a climatic chamber under controlled conditions. Two light intensities (30 and 90 µmol.m-2.s-1 ) were combined at temperatures of 21 and 31 °C and the growth rate and morphological changes were analysed. The morphotypes responded differently to the different temperatures and light intensities. Both strains exhibited faster growth velocities when submitted to higher light intensity and temperature. The lower temperature and higher luminosity hampered the development of both strains. Variations in cellular morphology and an absence of akinetes in both strains were related to the lower temperature (21 °C). The coiled morphotype demonstrated considerable phenotype plasticity, changing the morphology of trichome throughout its growth curve. Although molecular analysis does not sustain the separation of the morphotypes as distinct species, their different eco-physiological responses should be considered further knowledge of extreme importance for the population control of these potentially toxic organisms.

Effects of light intensity and temperature on Cylindrospermopsis raciborskii (Cyanobacteria) with straight and coiled trichomes: growth rate and morphology / Efeitos da intensidade luminosa e temperatura em Cylindrospermopsis raciborskii (Cyanobacteria) com tricomas retos e espiralados: taxa de crescimento e morfologia

Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju (Ordem Nostocales) is one of the most troublesome bloom-forming species in Brazil. Understanding the population dynamics of the different morphotypes of C. raciborskii (straight and coiled) could assist in the prediction of favourable conditions for the proliferation of this potentially toxin-producing species. The aim of the present study was to assess the effects of two different light intensities and temperatures on the growth rate and morphology of the trichomes of the straight and coiled morphotypes. For such, two non-toxin producing strains of C. raciborskii were used - one with a coiled trichome (ITEP31) and another with a straight trichome (ITEP28). The strains were cultured in BG-11 medium in a climatic chamber under controlled conditions. Two light intensities (30 and 90 µmol.m-2.s-1 ) were combined at temperatures of 21 and 31 °C and the growth rate and morphological changes were analysed. The morphotypes responded differently to the different temperatures and light intensities. Both strains exhibited faster growth velocities when submitted to higher light intensity and temperature. The lower temperature and higher luminosity hampered the development of both strains. Variations in cellular morphology and an absence of akinetes in both strains were related to the lower temperature (21 °C). The coiled morphotype demonstrated considerable phenotype plasticity, changing the morphology of trichome throughout its growth curve. Although molecular analysis does not sustain the separation of the morphotypes as distinct species, their different eco-physiological responses should be considered further knowledge of extreme importance for the population control of these potentially toxic organisms.

Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju (Ordem Nostocales) é uma das espécies formadoras de florações mais prejudiciais no Brasil. Entender a dinâmica populacional dos diferentes morfotipos de C. raciborskii (reto e espiralado) pode auxiliar a previsão de condições favoráveis à proliferação e ao estabelecimento dessa espécie potencialmente produtora de saxitoxinas e cilindrospermopsina. O objetivo deste estudo foi avaliar os efeitos de duas diferentes intensidades luminosas e temperaturas na velocidade de crescimento e na morfologia dos tricomas de morfotipos reto e espiralado. Para tanto, foram utilizadas duas linhagens de C. raciborskii, não produtoras de toxinas, sendo uma com tricoma espiralado (ITEP31) e outra com tricoma reto (ITEP28), cultivadas em câmaras climáticas sob condições controladas em meio BG-11. Duas intensidades luminosas, 30 e 90 µmol.m-2.s-1 , foram combinadas com temperaturas de 21 e 31 °C e avaliadas as velocidades de crescimento e modificações morfológicas. Os morfotipos responderam de maneiras diferentes às temperaturas e intensidades luminosas. As linhagens investigadas, independentemente do morfotipo, apresentaram maiores velocidades de crescimento em intensidade luminosa e temperatura altas. A condição de temperatura baixa e intensidade luminosa alta prejudicaram o desenvolvimento de ambas as linhagens. Variações na morfometria celular, bem como a ausência de acinetos para ambas as linhagens, estiveram relacionadas às condições de temperatura baixa (21 °C). O morfotipo espiralado apresentou grande plasticidade fenotípica, alterando a morfologia do tricoma ao longo de sua curva de crescimento. Apesar de a análise com ferramentas moleculares não sustentar a separação dos morfotipos em espécies distintas, devem-se considerar as diferentes respostas ecofisiológicas entre os mesmos como conhecimento de extrema importância no controle populacional desses organismos potencialmente tóxicos.

The aneurysmal bone cyst: report of a recent case encountered in dental practice.

BACKGROUND: A sixteen year-old African male with a large, hard swelling at the left gonial angle, presented at a private dental clinic in January 2009. The swelling felt warm, pulsating and was intermittently symptomatic. The unilocular, expansile lesion seen on a panoramic radiograph was provisionally diagnosed as an aneurysmal bone cyst on the basis of age, symptoms and clinical features. However, ameloblastoma was included in the differential diagnosis. METHODS: The histological examination of an incisional biopsy specimen revealed multiple blood-filled spaces separated by septa of fibrous tissue containing fibroblasts and multinucleated giant cells, thereby confirming the diagnosis of aneurysmal bone cyst. RESULTS: Unexpectedly, the patient failed to attend an appointment for curettage of the aneurysmal bone cyst by a maxillofacial surgeon. CONCLUSIONS: Over the past sixty-eight years, it had been postulated that the origin of the aneurysmal bone cyst was a secondary change in a large variety of pre-existing conditions. Other authors, however, have presented convincing evidence of the aneurysmal bone cyst as a primary lesion. More recently a cytogenetic aetiology for primary aneurysmal bone cysts has been postulated. Many factors in the aetiology of this rare and perplexing condition, however, still remain unclear.

An assessment of the relative safety of dental x-ray equipment.

Concern among patients, often prompted by medical practitioners, regarding the harmful effects of radiation caused by dental x-ray procedures, has caused several patients of the dental school of the University of Pretoria to refuse dental radiographic procedures. Buch and Fensham in a previous article demonstrated that radiation doses to the eyes and thyroid resulting from a single pantomogram constituted less than 10% of that which would be imparted by a transatlantic flight in terms of added natural background radiation. The authors in this study investigated doses to the same organs resulting from a full-mouth periapical series first using films and then digital imaging. Doses to the uterus resulting from these same examinations as well as from a pantomogram were also determined both with and without the use of a lead apron. Doses to the eye from a full-mouth examination using film compared favourably with those for a panoramic examination, but were much reduced when digital imaging techniques were employed. Doses to the uterus were small (equivalent to half a day of background radiation) for both a full-mouth examination using digital imaging, as well as for a pantomogram. However, from the results it would appear that there is little difference in the dose of scatter radiation to the uterus from a full-mouth examination whether or not a lead apron is used. The use of a lead apron for a pantomogram significantly reduces the dose to the uterus.

Identification of a 2244 base pair interstitial deletion within the human ESR1 gene in the Spanish population.

BACKGROUND: The ESR1 AGATA haplotype is composed of five markers located within introns 5 and 6 of the human oestrogen receptor 1 (ESR1) gene. This haplotype has been studied in several male urogenital tract anomalies and male infertility. In one of these studies, a deviation from Hardy-Weinberg equilibrium (DHW) was found for the ESR1 AGATA marker rs3020375 in two groups of healthy controls. In the present study, we investigated whether the observed DHW is caused by structural variants present within the ESR1 gene. PARTICIPANTS: 229 family units achieving pregnancy through assisted reproductive technologies (n = 129) or by natural means (n = 100), 2465 general Spanish population controls and 162 men with idiopathic infertility. MAIN OUTCOME MEASUREMENTS: Segregation analyses of genetic markers in family units and case-control genetic association studies. RESULTS: We identified a new interstitial deletion of 2244 base pairs within intron 6 of the human ESR1 gene as the cause for the observed DHW. This new variant presents a 10% allelic frequency in the general Spanish population and it is associated with idiopathic male infertility (OR = 1.51; p = 0.03). The percentage of infertile couples in which both members carried the ESR1 deletion (10.08%) was also a higher than expected value of 6% (p = 0.03). CONCLUSIONS: We have characterised a novel structural variation in human ESR1 gene. The available data indicate a deleterious action of the ESR1 deletion in both male and couple fertility. The potential effects of this deletion on other oestrogen-related diseases need to be determined.

Association of genetic markers within the KIT and KITLG genes with human male infertility.

BACKGROUND: There is much evidence involving the KIT tyrosine kinase receptor and its ligand KITLG in the survival and proliferation of germ cells. Animal models and functional studies in humans suggest that this signalling pathway plays a role in male infertility. METHODS: We studied three and two single-nucleotide polymorphisms (SNPs) (rs3819392, rs3134885, rs2237012, rs10506957 and rs995030) located within the genomic region of the KIT and KITLG genes, respectively. A total of 167 idiopathic infertile men (sperm counts <5 million spz/ml) and 465 unrelated healthy controls from the same geographical region were genotyped for these SNPs. RESULTS: We found a statistically significant association of the rs3819392 polymorphism, which is located within the KIT gene, with idiopathic male infertility. In addition, a deviation from the Hardy-Weinberg equilibrium (HWE) law was observed for rs10506957 polymorphism within the KITLG gene only in the infertile group. CONCLUSIONS: Our data indicate that the KIT/KITLG system may be involved in a low sperm count trait in humans.

Orthodontic radiographic procedures--how safe are they?

Parents of children subjected to radiographic procedures for orthodontic purposes occasionally express concern about possible radiation overdose to sensitive structures in the head and neck region. The following study was designed to determine this. Twenty Harshaw lithium fluoride thermoluminescent dosimeters (TLDs) were irradiated using a calibrated RT 100 X-ray source. These were read in a Toledo 654 TLD reader. The readings of all dosimeters fell within 10% on either side of the mean reading for the dosimeters. Twelve were finally selected which fell closest to the mean. Six of the TLDs were randomly selected and placed in a Rando female phantom in a position corresponding to the lens of the eye-3 in the left and 3 in the right eye. A standard pantomogram was taken of the phantom using an Orthophos machine. The TLDs were then replaced by another two groups of 3 in the same positions in the phantom and a lateral cephalogram taken on the same machine. The TLDs were read in the Toledo reader. Six of the 12 TLDs were then randomly selected for re-use. Three were placed in the phantom in the region of the thyroid and a pantomogram again taken. The procedure was repeated for a cephalogram and the TLDs again read. In all cases the readings of each group of 3 TLDs did not vary by more than 10% on either side of the mean readings. The TLD readings were then converted by means of a conversion factor to actual dose measurements. The doses to left and right eyes and to the thyroid were respectively found to be 0,0151, 0,0222 & 0,0896 mSv for the pantomogram and 0,0351, 0,0183 & 0,0177 mSv for the cephalogram--an almost insignificant dose in terms of the "background equivalent" concept.

Gardner's syndrome--the importance of early diagnosis: a case report and a review.

Gardner's syndrome (familial polyposis coli) is a genetic condition characterised by colonic polyps that carry a 100% risk of malignancy if untreated. Early diagnosis, in which an astute and knowledgeable dentist can play an essential role, is therefore of paramount importance. The presence of multiple unerupted teeth provides the dentist with a major pointer to the possible presence of this disease, which may be provisionally diagnosed on the detection of two other obvious features, namely osteomas and cutaneous lesions. This fact is clearly illustrated by the accompanying case report. Extracolonic manifestations increase the morbidity and make treatment more difficult. The presence of large desmoid tumours may be a serious complicating factor. Gardner's syndrome may be accompanied by adenomas of the stomach and duodenum and very rarely by malignant tumours of the central nervous system. Regular surveillance by means of colonoscopies must be carried out on all individuals suspected of having the disease in order to implement timeous life-saving prophylaxis.

Primary subtaler arthrodesis for the treatment of comminuted calcaneal fractures.

We retrospectively evaluated the results of primary subtalar arthrodesis for the treatment of severely comminuted calcaneal fractures. Of 108 patients with 112 calcaneal fractures treated at our institution between 1989 and 1992, 16 (15%) underwent primary subtalar arthrodesis through an extensile lateral approach. The calcaneal height and width were restored with standard fixation techniques and then arthrodesis was performed with bone graft and fixation by 7.0-mm cannulated cancellous screws. Fourteen patients (12 males and 2 females; mean age, 40 years) were available for examination at a mean time of 26 months (range, 12-54 months) after surgery. Arthrodesis, evidenced by radiographic bony bridging across the arthrodesis site, was present in all patients between 8 and 12 weeks. Minor wound complications occurred in three patients. Of the 12 patients employed before the injury, 11 returned to their original occupations at a mean time of 8.8 months after injury (range, 1 month to 3 years). The mean AOFAS 100-point clinical rating scale score, evaluating pain, function, and alignment, was 72.4 points (range, 48-88 points). We conclude that primary subtalar arthrodesis is indicated as part of the management of comminuted displaced articular calcaneal fractures, yielding results that allowed 11 of 12 formerly employed patients to return to work.

The Mitek Mini G2 suture anchor: biomechanical analysis of use in the hand.

We inserted 36 Mitek Mini G2 suture anchors (Mitek Surgical Products, Westwood, MA) into various sites of 14 fresh cadaver hands. A single-strand 0-Ethibond suture (Ethicon, Sommerville, NJ) was threaded through each anchor, inserted into bone, and loaded to failure. In all cases, either the anchor pulled out (11 of 36) or the suture broke (25 of 36). No anchors fractured. We also measured the breaking strength of six types of suture material (without anchors) commonly used by hand surgeons; all failed at much lower loads than those generated in our anchor pullout model. We conclude that the Mitek Mini G2 suture anchor possesses sufficient pullout strength for tendon and ligament fixation in the hand, including the distal phalanx.

Salter-Harris type IV epiphyseal fracture of the proximal phalanx of the great toe: a case report.

Epiphyseal fractures account for about one fifth of pediatric fractures. Approximately 10% cause major growth disturbances, depending on the location and type of the fracture and the skeletal maturity of the child. Intraarticular Salter-Harris type IV fractures are rare, carry a poor prognosis, and almost always need surgical reduction to prevent deformity. We present a case report of a pediatric patient who returned to normal function after the successful surgical reduction of a Salter-Harris type IV fracture in the proximal phalanx of the great toe.

Localization of impacted teeth utilizing inherent panoramic distortions.

Distortions in the size of images seen on panoramic radiographs can assist the clinician in determining the site of impacted teeth in relation to the dental arch. Application of this principle can often eliminate the necessity for additional radiographic views and prevent exposure of the patient to unnecessary radiation.