Radiographic differences observed following apexification vs revascularization in necrotic immature molars and incisors: a follow-up study of 18 teeth.

PURPOSE: To evaluate the effectiveness of apexification versus revascularization in the treatment of necrotic immature teeth and determine which strategy affords the greatest radiological success rate. METHODS: An analysis was made of 18 teeth subjected to mineral trioxide aggregate (MTA) apical plugging and regenerative endodontic treatment, assessing healing of the apical lesions and the changes in root dimensions. RESULTS: Significantly greater root growth was observed with revascularization in terms of the percentage change in length (12.75% at 6 months) and dentin thickness (34.57% at 6 months) (p < 0.05). There were no significant differences between the two treatments in terms of the apical healing scores after 6 months of follow-up (p > 0.05). CONCLUSION: Apexification with an MTA apical plug and pulp regeneration are reliable treatments for non-vital immature teeth. The radiographic outcomes are comparable between the immature teeth subjected to MTA apexification versus those subjected to revascularization. The results of the present study indicate a greater increase in root length and width with regenerative endodontic treatment.

Are there any differences between first and second primary molar pulpectomy prognoses? A retrospective clinical study.

AIM: To determine if there are any significant differences between the prognoses of pulpectomies done on first and second primary molars of the upper and lower dental arch. MATERIALS AND METHODS: Study Design: The clinical study included 55 children who had undergone 86 pulpectomy treatments, 41 on the first molars and 45 on the second molars. The root canal filling material consisted of a paste based on Walkhoff formula, containing Kri-1, calcium hydroxide and meta-cresol formaldehyde. The same clinician carried out all pulpectomies. RESULTS: After the analysis there were a total of 7 treatment failures (3 in the upper arch and 4 in the lower). Four of the 7 failures were first primary molars and three were second primary molars. STATISTICS: There were no significant differences in the prognoses of the different kinds of primary molars. CONCLUSION: The anatomy of the primary molars changes considerably. Significant differences were not observed in the prognosis of different types of primary molars after pulpectomy.

Intrusive Luxation in Primary Teeth: A Case Report.

BACKGROUND: Intrusive luxation, also called central dislocation, is often the result of an axial impact in the apical direction, moving the tooth within the alveolar bone. This is possibly one of the most traumatic injuries, since the displacement of a tooth within its socket implies extensive and acute involvement of the periodontal ligament, bone damage and rupture of the neurovascular bundle. The close relationship between the apexes of the primary teeth and the developing permanent successor in turn can lead to multiple complications, which are greater when the permanent tooth is affected in the early stages of development. METHODS: The present paper describes a case of intrusion in primary teeth and its evolution following initial diagnosis as avulsion at the time of trauma. RESULTS: The upper right central incisor, initially diagnosed as avulsed, was lodged in the floor of the right nostril, and was surgically extracted through the nose. CONCLUSIONS: In cases of intrusion of primary teeth, it is essential to diagnose the direction of the displaced tooth to rule out injury to the successor and thus prevent the occurrence of sequelae in the permanent dentition.

Osteopontin gene SNPs (rs9138, rs11730582) mediate susceptibility to external root resorption in orthodontic patients.

OBJECTIVE: External apical root resorption (EARR) is a frequent iatrogenic effect of orthodontic treatment. Substantial variability in responses to postorthodontic EARR has been observed among patients even when similar treatment protocols were used. This observation suggests that environmental and/or genetic variations between individuals may confer susceptibility or resistance to developing EARR. The objective of this study is to determine whether variants in the osteopontin gene, an essential mediator in the odontoclast fusion and attachment process, are positively/negatively associated with postorthodontic EARR. MATERIALS AND METHODS: Genetic screening of eighty-seven orthodontic patients was performed for two polymorphisms in the osteopontin gene cluster (rs9138 and rs11730582). Subjects were divided into groups, according to the presence or absence of EARR (>2 mm). Genotype distributions and allelic frequencies were calculated using the chi-square test. Logistic regression analysis was used to assess the extent to which clinical-related parameters interfered with the EARR. Odds ratios (OR) and 95% confidence intervals were also calculated. RESULTS: Data from this study show that subjects heterozygous and homozygous for the most frequent allele of the osteopontin gene at position 89261521 [OR: 0.035 (P = 0.035*) (allele A)] and 89253600 [OR: 0.20 (P = 0.025*) (allele T)], respectively, are protected against postorthodontic EARR. Nevertheless, a highly significant association was found in the comparative analysis of homozygous subjects [2/2 (CC)] for the osteopontin gene (rs9138), resulting in an increased risk of suffering postorthodontic EARR[OR: 4.10; P = 0.045*; CI: 95%]. Subjects who were homozygous [2/2 (CC)] for the osteopontin gene (rs11730582) were more likely, and to a greater extent, to be affected with EARR [OR: 11.68; P < 0.039*; CI: 95%] compared with other genotypes. CONCLUSION: Variations in the osteopontin gene (rs9138 and rs11730582) are determinants of a genetic predisposition to suffer EARR secondary to orthodontic treatment.

Revascularization of immature permanent teeth with apical periodontitis.

The aim of this minireview was to identify and review the scientific evidence regarding regenerative endodontic protocols claiming to revascularize permanent immature teeth with apical periodontitis. The literature was identified using the PubMed/MEDLINE, Scopus, Scirus, EMBASE and Cochrane databases up to February 2013. Studies were selected independently by two different researchers (kappa index: 0.88), based on established inclusion/exclusion criteria. The methodological quality of the reviewed papers was classified as high, medium or low (HQ, MQ, LQ). The search strategy identified 285 titles. Nine studies, both human and animal based, were selected after application of the criteria (LQ:5; MQ:4). In most of these studies (seven of nine), the revascularization protocol included a triple antibiotic combination as canal disinfectant for a period of 1-4 weeks after blood clot formation (LQ:5; MQ:4), although there is no clear consensus about the treatment protocol. Two studies reported tooth discoloration after the revascularization process (LQ:2), and only three (LQ:1; MQ:2) reported a success rate of 54.9% in dogs and 73.6% and 80% in humans, respectively. Revascularization of immature permanent teeth with apical periodontitis is possible and preferable to apexification. Nevertheless, there is a widespread lack of randomized clinical trials and blinded measures. In addition, the small sample sizes that are common in these studies as well as the generally low quality of the analysed publications require the results to be viewed with caution. There is a high risk of bias, with a low quality of available information, for developing clinical guidelines for regenerative endodontic protocols; rigorous randomized clinical trials are therefore needed.

Do the smiles of the world's most influential individuals have common parameters?

The aim of this study was to determine - on the basis of the most recent yearly listings - whether there were any common measurable variables associated with the smiles of the world's most influential people. A total of 168 subjects were selected from the lists of Time magazine's 100 most influential people during the period 2006-2010. Smiling frontal view photographs were obtained. Thirty-six variables for each subject were traced and measured using photogrammetric analysis to obtain qualitative and quantitative proportions and measurements. Differences with respect to gender, occupation and year of listing were tested to 95% significance, using the Student's t-test and the Kruskal-Wallis test. The chi-squared test was used for qualitative variables. Irrespective of gender or occupation, the similar quantifiable characteristics of the smiles of the most influential subjects were the following: vertical upper lip proportion, smile width, incisor exposure, buccal corridor ratio, smile symmetry index and intra-dental proportions (P > 0·05). Other qualitative standards were as follows: smile symmetry, the buccal corridors and smile arc, direction of occlusal cant and the degree of deviation between maxillary and facial midlines. Differences were found for gingival display and smile height parameters (P = 0·001). The smiles of the world's most influential people revealed common standards, regardless of occupation or gender, which may play a decisive role in the expressions of influential faces.

Current concepts on the effect of environmental factors on cleft lip and palate.

The aim of this study was to investigate the effect of environmental factors, such as tobacco, alcohol and folic acid intake, obesity, stressful events, low blood levels of zinc and fever during pregnancy, on the incidence of cleft lip and/or palate (CL±P). An electronic search was performed in the Cochrane Reviews, the ISI Web of Knowledge, PubMed and Scopus, along with a manual search to identify other relevant case-control and cohort studies. Quality assessments and an evaluation of publication bias were undertaken. Statistical heterogeneity was examined, and odds ratios (ORs) and 95% confidence intervals (CI) estimated using the random effects model. Of 372 articles initially retrieved, 28 studies were selected as eligible for meta-analysis. No evidence of publication bias was found using funnel plot analysis and the Egger linear regression method. Many studies were classified as low quality due to inadequate case-control data. On the basis of this research, maternal factors most associated with CL±P were: tobacco (OR 1.48), alcohol (OR 1.28), folic acid intake (OR 0.77), obesity (OR 1.26), stressful events (OR 1.41), low blood zinc levels (OR 1.82), and fever during pregnancy (OR 1.30). Folic acid intake by the mother reduced the risk of CL±P in offspring (OR 0.77).

Interleukin 1 gene cluster SNPs (rs1800587, rs1143634) influences post-orthodontic root resorption in endodontic and their contralateral vital control teeth differently.

AIM: To investigate whether the genetic variants of the interleukin-1 gene cluster (IL1) are associated with a possible genetically induced variability in post-orthodontic external apical root resorption (EARR) in root filled teeth and their control counterparts with vital pulps. METHODOLOGY: One hundred and forty-six maxillary premolars were evaluated radiographically following orthodontic treatment. Genetic screening was performed on orthodontic patients for two single-nucleotide polymorphisms (SNPs: rs1800587 and rs1143634) in the IL1 gene cluster. Subjects were divided into two groups according to the presence or absence of radiographic post-orthodontic EARR (>2 mm) in root filled teeth and their controls with vital pulps. Logistic regression analysis was performed to obtain an adjusted estimation between EARR and IL1 polymorphisms. Allelic frequencies, genotype distributions, and adjusted odds ratio (OR), at 95% confidence interval, were also calculated. RESULTS: Whilst no clear statistical association was found for gene variations in IL1A, a sound association was found in the comparative analysis of subjects homozygous [2/2(TT)] for the IL1B gene, which resulted in a two times increased risk of suffering post-orthodontic EARR in root filled teeth [OR, 2.032 (P = 0.031); CI,1.99-14.77] when compared with their controls with vital pulps. There was, however, a shared predisposition to EARR in controls with vital pulps and root filled teeth of subjects homozygous for allele 1 [OR, 5.05 (P = 0.002)] and [OR, 2.77 (P = 0.037)], respectively. CONCLUSIONS: Genetic variations in the interleukin-1ß gene (rs1143634) predispose root filled teeth to EARR for matched pairs secondary to orthodontic treatment in a different way from their control teeth with vital pulps in subjects homozygous for allele 2 [2/2(TT)].

Retrospective long-term evaluation of autotransplantation of premolars to the central incisor region.

AIM: This retrospective case-series study aimed to examine the long-term outcomes of autogenously transplanted premolars. METHODOLOGY: Twelve patients in whom donor premolars were used to replace maxillary central incisors lost by trauma were clinically and radiologically monitored. Standardized clinical and radiographic records were systematically obtained during the follow-up period of 14 years, to determine the influence of specific clinical criteria on the overall success rate of transplantation. RESULTS: The success rate of premolar autotransplantation in the maxillary central incisor area was 80% after 14 years follow-up. The highest success rate occurred in those teeth transplanted with two-thirds of full root development. Complete pulp obliteration was positively related to autotransplant viability, followed by root formation in the bony crypt. CONCLUSIONS: Autotransplantation of donor teeth, at the stage of ½ to ¾ of their expected root length, can provide a successful treatment solution for over 14 years.

Postorthodontic external root resorption is associated with IL1 receptor antagonist gene variations.

OBJECTIVE: External apical root resorption (EARR) is a frequent iatrogenic effect of orthodontic treatment. Patients with genetic variants in the interleukin 1 gene have been related to an increased risk of suffering EARR. The objective of this study is to determine whether variants in the interleukin 1 receptor antagonist gene are positively/negatively associated with interleukin 1 gene polymorphisms, particularly in relation to the clinical features of EARR patients. MATERIALS AND METHODS: Genetic screening of 54 orthodontic patients was performed for three polymorphisms (rs1800587, rs1143634 and rs419598) in the IL1 gene cluster. Subjects were divided according to the presence or absence of EARR of more than 2 mm. The genotype distributions and allelic frequencies were calculated by the chi-square-test. Odds ratios (OR) and 95% confidence intervals were also calculated. RESULTS: A highly significant association was found in the comparative analysis of homozygous subjects [1/1(CC)] for the IL1B gene, resulting in an increased risk of suffering postorthodontic EARR (OR: 3.47; P = 0.027; CI: 95%). While no association was found for the IL1A gene (P = 0.097), subjects who were homozygous [1/1(TT)] for the IL1RN gene were more likely to be affected with EARR (OR: 6.75; P = 0.001; CI: 95%). CONCLUSION: Variations in the interleukin 1 receptor antagonist gene (rs419598) - and not only in the IL1B gene (rs1800587) - are determinants of a predisposition to postorthodontic EARR.

Maxillary protraction at early ages. The revolution of new bone anchorage appliances.

PURPOSE: An update is provided on the different types of early treatment for class III malocclusions of maxillary origin. There is an increasing tendency to prescribe maxillary orthopedic treatment with skeletal anchorage, with the purpose of enhancing the skeletal and reducing the dentoalveolar effects--offering a management option for children with important deformations that otherwise would have to wait until adult age to receive surgical treatment. METHOD: A literature review has been made of maxillary bone orthopedic traction appliances in growing children with class III malocclusions. A Medline (PubMed) search was made using the following MeSH terms: Cephalometric, Child, Malocclusion class III/therapy, Extraoral traction appliances, Palatal expansion, Bone plates, Skeletal anchorage, Orthodontic anchorage. RESULTS: Many articles show that the greatest maxillary advances are obtained at very early ages, though with a greater tendency towards relapse. However skeletal anchorage has been seen to afford a lesser relapse rate and greater dentofacial orthopedic efficiency due to its low dentoalveolar impact. In any case, further randomized clinical studies are needed to firmly establish the quantifiable differences in terms of maxillary advance, optimum traction age, optimum traction appliance and potential side effects. At present, the incorporation of surgically inserted bone anchorage appliances (miniplates and miniscrews) offers a purely orthopedic approach to treatment, with minimization of the undesirable side effects of traditional dentofacial orthopedic compensation based on dentoalveolar anchorage. Nevertheless, further studies are needed to consolidate the supporting scientific evidence in this field.

The use of gene therapy vs. corticotomy surgery in accelerating orthodontic tooth movement.

OBJECTIVE: Alveolar corticotomy surgery is an adjunctive therapy for reducing orthodontic treatment duration. The activation pathways of bone resorption involved in the tooth movement (TM) process are directly linked to the receptor activator of the nuclear factor-kB ligand (RANKL). Whether similar molecular pathways through RANKL, are shared by the acceleratory TM process (corticotomy-induced or not), sustained acceleration would therefore be expected with transgenic overexpression of this factor. We hypothesize that maintaining transgenic overexpression of RANKL will accelerate TM under force over time rather than at the beginning of therapy only; this contrasts with the corticotomy procedure. MATERIAL AND METHODS: We transfected the pcDNA3.1(+)-mRANKL transgene in vitro into NIH3T3 cells, then evaluated by PCR, Western blot and ex vivo resorption assay. Quantification of RANKL immunofluorescence, fluorescence-based tartrate-resistant acid phosphatase+ (TRAP+) osteoclast counts and histological analyses of the bone resorption area were performed and clinically correlated after a 32-day in vivo experiment comparing corticotomy and gene therapy. RESULTS: In vitro experiments resulted in increased level of RANKL protein (46%, p<0.05) and greater mineral resorption (39%, p<0.05) compared to the controls. In vivo results showed increased RANKL immunoexpression for both corticotomy (twofold) and transfection groups (threefold) after 10 days. After 32 days, a similar result was obtained for the transfected group but not for the surgery group. These data correlate with the clinical effect of decelerating TM in the surgery group. CONCLUSIONS: Selective gene therapy with RANKL has been experimentally tested as an alternative method to corticotomy surgery, showing higher effectiveness than surgical methods used for acceleratory purposes in orthodontics.

Treatment of an avulsed maxillary permanent central incisor replaced by autotransplantation of a mandibular premolar: 14-year follow-up.

AIM: To present the 14 year follow-up of a case in which an avulsed permanent maxillary central incisor was replaced by autotransplantation of a mandibular premolar. SUMMARY: A mandibular premolar (Moorrees' stage 3) was transplanted into the space left by an avulsed permanent maxillary central incisor after a delay of 3 months. Recall examination 14 years after transplantation revealed a normal periodontal architecture with absence of infection, ankylosis or progressive resorption. The transplantation of a premolar is seen as a promising method to replace a lost permanent tooth and to restore aesthetics and function. KEY LEARNING POINTS: * Autotransplantation is a viable option for the treatment of a missing tooth or for replacement of avulsed and traumatized tooth when a donor tooth is available. * Autotransplantation is a therapeutic option for the substitution of missing anterior teeth in young patients who also need orthodontic treatment.

Multiple environmental signals determine the transcriptional activation of the mycoparasitism related gene prb1 in Trichoderma atroviride.

Trichoderma atroviride parasitizes a large variety of phytopathogenic fungi. This characteristic has allowed its use as a biological control agent. The production of hydrolytic enzymes appears to be a key element in the parasitic process. Among the enzymes released by Trichoderma, the proteinase Prb1 plays a major role. We show here that the corresponding gene ( prb1) is subject to nitrogen catabolite repression. Accordingly, induction of prb1 transcription by Rhizoctonia solani cell walls and by osmotic stress requires release from a repressed condition, which is determined by nitrogen availability. Furthermore, the transcription pattern of the prb1 gene was not affected when an inhibitor of p38-Hog1, a regulator of the response to osmotic shock, was used. In contrast, a MEK1/2 (MAPK/ERK) inhibitor blocked prb1 transcription in response to nitrogen limitation, indicating that the pathway employed in the nitrogen response involves proteins similar to p42-p44. Fusion of the prb1 promoter to the gfp reporter gene allowed the detection of a novel regulatory element, providing an initial insight into the nature of the sites that control prb1 expression.

Hexahélix: distalador intraoral de doble función.Eficacia en el distalamiento / The hexahelix: intraoral distalization appliance

El hexahelix es un aparato de distalamiento intraoral, que consta de un botón de acrílico fijado mediante bandas a los primeros molares con dos brazos en forma de "L" en los que se configuran tres espirales por brazo. Dependiendo del brazo activado se producirá distalamiento simétrico o asimétrico. Una vez alcanzada la relación de súper Clase I, el botón de acrílico se desconectará de las bandas de los primeros premolares, quedando convertido en un botón de Nance, sirviendo a partir de ese momento como aparato de anclaje para el distalamiento de premolares y canino de forma consecutiva hasta alcanzar la Clase I en todo el sector lateral. Finalmente, el botón de acrílico podrá ser eliminado para completar la retrusión del sector incisivo. (AU)

Intrusor molar / The molar intrusor

El intrusor molar es una variación de la barra transpalatina de Goshgarian, consistente en incorporar un botón de acrílico sobre la omega construida con su giro en dirección mesial, constando a su vez de dos espirales al inicio de las acodaduras transversales de la omega y de dos pequeñas ondas que aumentarán transversalmente la longitud de la barra. Al aumentar la superficie de apoyo de la lengua, la presión que ésta transmite se convierte en una fuerza intrusiva sobre los molares provocando un cambio en el plano oclusal en sentido antihorario, favoreciendo una proyección más anterior de la mandíbula y una disminución de la altura facial interior. Su uso estará especialmente indicado para el control vertical de los molares en los casos de Clase I, con tendencia a la mordida abierta y posterrotación mandibular. (AU)

[Prevalence of asthma in schoolchildren from the Mexican city Hermosillo]. / Prevalencia de asma en niños escolares de la ciudad mexicana de Hermosillo.

Asthma is a very common disease, but its prevalence greatly varies from region to region, even in the same country. In the northwest of Mexico there is a lack of epidemiological studies on this disease. In this work a standardized questionnaire (ISAAC) was applied to parents of children attending 8 primary schools in the Mexican city of Hermosillo, Sonora. Of 3000 questionnaires sent, 1489 (49%) were acceptably answered. Children were of either sex and 9.1 +/- 1.8 years old (mean +/- SD). From this population, 74 (10.4%) out of 713 male and 67 (8.6%) out of 776 female children had an affirmative response to que question "Have you ever had asthma?", from which we conclude that global prevalence of asthma in the studied sample was 9.5%, an intermediate figure among those reported from other studies performed in Mexico.

Intracellular calcium and alpha 1b-adrenoceptor phosphorylation.

BACKGROUND: Desensitization of G protein-coupled receptors is associated with receptor phosphorylation. Two groups of kinases seem to participate in such receptor phosphorylation, i.e., second messenger-activated protein kinases and G protein-coupled receptor kinases. Calcium seems to play a role in the phosphorylation of some G protein-coupled receptors. The role of calcium in alpha 1b-adrenoceptor phosphorylation has not been critically assessed. METHODS: Rat-1 fibroblasts stably expressing the hamster alpha 1b-adrenergic receptor were used. To study receptor phosphorylation cells metabolically labeled with [32P]Pi were lysed and the receptor immunoprecipitated using a polyclonal antibody generated against the receptor carboxyl terminal decapeptide. Intracellular calcium was determined by using Fura-2 fluorescence. RESULTS: Norepinephrine, endothelin-1, and lysophosphatidic acid increased intracellular calcium concentration. All these agents and phorbol myristate acetate (PMA) induce alpha 1b-adrenoceptor phosphorylation. The intracellular chelator, BAPTA, abolished the increase in intracellular calcium induced by the previously mentioned agents but did not affect the receptor phosphorylation induced by norepinephrine, PMA, or lysophosphatidic acid. Under these conditions, receptor phosphorylation induced by endothelin was slightly but consistently decreased. Thapsigargin increased intracellular calcium concentration but was unable to induce alpha 1b-adrenoceptor phosphorylation and decreased PMA-induced receptor phosphorylation. No increase in receptor phosphorylation was observed when calcium ionophores were used. CONCLUSIONS: Our data indicate that an increase in [Ca2+]i is not sufficient to induce alpha 1b-adrenoceptor phosphorylation and that buffering of [Ca2+]i does not alter the receptor phosphorylation induced by norepinephrine, lysophosphatidic acid, and PMA. A marginal role of calcium in the alpha 1b-adrenoceptor phosphorylation induced by endothelin-1 cannot be discarded.

Chloroquine inhibits alpha1B-adrenergic action in hepatocytes.

Noradrenaline increased phosphorylase a activity through activation of alpha1B-adrenoceptors in rat hepatocytes. Such effect was inhibited by chloroquine (Ki approximately 55 nM) and only slightly reduced by high concentrations of primaquine. Chloroquine did not inhibit the activation of phosphorylase a induced by vasopressin or angiotensin II. Binding competition experiments using [3H]prazosin showed that both chloroquine and primaquine interact with alpha1B-adrenoceptors, but only at very high concentrations. This indicates that the ability of chloroquine to block the alpha1B-adrenergic action was not due to antagonism at the receptor level. Noradrenaline increased phosphatidylinositol resynthesis and inositol trisphosphate production; these effects were inhibited by chloroquine and phorbol 12-myristate 13-acetate. Staurosporine and Ro 31-8220 (3-[1-[3-(amidinothio)propyl-1H-indol-3-yl]-3-(1-methyl-1H-indol-3 -yl)maleimide), reduced the inhibitions induced by the active phorbol ester and the antimalarial drug on adrenergic-stimulated phosphatidylinositol resynthesis. Similarly, staurosporine blocked the inhibitory actions of chloroquine and phorbol 12-myristate 13-acetate on noradrenaline-stimulated inositol trisphosphate production. These data suggest the possibility that protein kinases, such as protein kinase C, could be involved in the actions of chloroquine.

Crosstalk: phosphorylation of alpha1b-adrenoceptors induced through activation of bradykinin B2 receptors.

The action of bradykinin was studied in rat-1 fibroblasts stably expressing alpha1b-adrenoceptors. It was observed that bradykinin and kallidin markedly increase cytosol calcium concentration, but that the B1 agonist, des-Arg9-bradykinin, only mimicked this effect to a minimal extent. Antagonists, selective for the B2 subtype, such as Hoe 140, blocked this effect of bradykinin and kallidin. Similarly, bradykinin and kallidin stimulated the production of inositol phosphates and B2 antagonists blocked their actions. The possibility that bradykinin could modulate alpha1b-adrenoceptors was studied. It was observed that bradykinin and kallidin increased alpha1b-adrenoceptor phosphorylation and that such effect was also blocked by Hoe 140. Interestingly, the ability of norepinephrine to increase intracellular calcium concentration was not altered by pretreatment of the cells with bradykinin, i.e. bradykinin induced alpha1b-adrenoceptor phosphorylation but this did not lead to receptor desensitization.