Idiopathic bone cavity mimicking a botryoid odontogenic cyst: A rare radiographic presentation in an older adult.

OBJECTIVES: This report describes an unusual case of a multilocular idiopathic bone cavity (IBC) that presented as a botryoid odontogenic cyst situated between the mandibular lateral incisor and canine in an older adult. BACKGROUND: The IBC represents an intraosseous concavity that appears radiographically as a unilocular or multilocular radiolucent lesion found in various skeletal sites, including the jaw. Atypical cases of gnathic IBC have not been appreciated in the gerodontologic literature. MATERIALS AND METHODS: The teeth adjacent to the bony lesion had normal pulpal responses to cold. A full-thickness flap was elevated and provided a direct entry into a bony concavity, which was devoid of an epithelial lining and fluid. RESULTS: The lack of a cystic lining within the empty osseous lesion following surgical entry, concomitant with the vital pulpal status of the proximal teeth, led to a diagnosis of an IBC. The bony walls underwent curettage and copious irrigation prior to primary closure. A 10-month follow-up revealed partial evidence of osseous repair. The patient will continue to be monitored. CONCLUSION: Timely surgical intervention of central lesions of the jaws may improve clinical outcomes. Variants of the IBC should be included in the differential diagnosis of multilocular lesions, particularly in the geriatric population.

Leiomyoma with Uncommon Localization-Incisive Papilla and Palatal Fibromucosa: A Case Report.

The current paper presents a case of a 33-year-old female with an uncommon localization of a leiomyoma in the oral cavity-the anterior palatal fibromucosa and the incisive papilla. The patient referred to the Oro-Maxillo-Facial Surgery Clinic of Emergency City Hospital Timisoara, Romania, complaining of a slight discomfort in the act of mastication and the occurrence and persistence of a diastema between the upper central incisors, due to the presence of a nodule located in the anterior palatal mucosa, between the upper central incisors, without any changes of the subjacent bone structure in the anterior hard palate visible on a cone beam computed tomography image (CBCT). The lesion was removed using a surgical excisional biopsy and a histopathological examination was performed using morphological Hematoxylin-Eosin (HE) staining and additional immunohistochemical (IHC) reactions, in order to confirm the diagnosis. On microscopic examination, bundles of spindle cells were found with eosinophilic cytoplasm and vesicular nuclei, with finely granular chromatin. The immunohistochemical reactions were positive for smooth muscle actin (SMA) and desmin and negative for vimentin. The treatment of choice for leiomyoma of the oral cavity is surgical excision with clear margins, followed by periodical clinical monitoring.

Management of compound odontoma with 70 denticles and impacted lateral incisor over an 8-year follow-up.

Odontomas are benign developmental tumors formed by the improper growth of completely differentiated epithelial and mesenchymal cells of odontogenic origin. The etiology of odontoma is unknown and it is detected during routine radiographic examination. The ideal management is early detection and surgical enucleation. The commonly associated clinical problems of odontomas are delayed exfoliation of primary teeth, delayed eruption or impaction of permanent teeth, displacement of teeth, root resorption, congenital missing, and widening of follicular space. Here, we describe a unique case of compound odontoma with a high number of denticles managed based on a definite decision support system over 8 years. An 8-year-old boy with 70 denticles in the left maxillary region underwent enucleation. On periodic follow-up, the associated impacted lateral incisor was extruded orthodontically.

Unusual Lesion Caused by Food Displacement Into the Oral Mucosa, Mimicking a Sinus Tract.

This article reports an unusual case of foreign body lesion on the oral mucosa. A 61-year-old man, with no previous traumatic episode, presented with a small swelling resembling a sinus tract on the mucosa in the anterior mandible, adjacent to the left central and lateral incisors. Because of a discrete drainage of serous/purulent exudate, the clinician initially suspected endodontic involvement; however, the adjacent teeth were caries-free, responded positively to pulp tests, and the periapical tissues were radiographically normal. Exploration of the lesion opening under an operating microscope revealed a small seed associated with a dark filamentous structure; both were removed and processed for histologic examination. The seed was from a fig, and was germinating under the mucosa conditions. Bacterial colonization of the vegetable structures and polymorphonuclear leukocyte accumulations were histologically observed. The mucosa healed completely and uneventfully over the following weeks.

Sequential Loss of Mandibular Permanent Incisors in Noonan Syndrome.

BACKGROUND: Noonan syndrome (NS) is a multigenic disorder with a highly variable phenotype. Cardiac disorders and a predisposition to neoplasm often require early medical attention. Central giant central lesions (CGCLs) of the jaws are part of the phenotype. CASE REPORT: In a patient with genetically confirmed NS and multiple teeth loss presumably caused by CGCL, careful review of the medical history and radiographic findings made it probable that the cause of tooth loss was cervical root resorption (CRR) of the teeth following long-term orthodontic therapy. CONCLUSION: CRR is a rare dental disease of unknown origin. However, association with prior orthodontic therapy is well documented. In NS, mandibular lesions can occur which, at first glance, might lead the examiner to assume that it is a CGCL, but on closer analysis, obviously are of non-tumorous origin and should be assessed as coincidental. The report adds relevant information to orthodontic treatment of NS patients.

Measuring distance from the incisors to the esophageal cancer by FDG PET/CT: endoscopy as the reference.

BACKGROUND: Using endoscopy as the reference, this study evaluated the accuracy of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in measuring distance from the incisors to the PET detectable esophageal cancer. If there is high concordance between endoscopic and PET measurements, our results may provide a basis to use FDG PET/CT in cooperation with endoscopic measurement to localize those PET/CT and CT undetectable esophageal tumors for radiotherapy planning. MATERIALS: Esophageal cancer patients with pretreatment endoscopy and FDG PET/CT detectable esophageal tumors were recruited retrospectively. The distances from the incisors to the proximal esophageal tumor margins were determined by endoscopy and by the sagittal images of FDG PET/CT. The endoscopic measurement was used as the comparative reference. A nuclear medicine doctor and a radiation oncologist each performed the FDG PET/CT measurement twice for every patient. We analyzed the differences in these measurements, and assessed agreement and reproducibility of the results by the intraclass correlation coefficient (ICC). RESULTS: Thirty-four patients, with 35 esophageal tumors, were included. By endoscopy and FDG PET/CT, the mean distances from the incisors to the proximal esophageal tumor margin were 27.3 ± 6.4 cm (range 17.1-40.0 cm) and 26.8 ± 6.3 cm (range 15.7-41.3 cm), respectively. The mean absolute differences between the endoscopic and four FDG PET/CT measurements ranged from 1.129 to 1.289 cm (SD: 0.98-1.19). The measurement agreement between FDG PET/CT and endoscopy by ICC was between 0.962 and 0.971. The intra- and interobserver reproducibilities of the two readers were excellent (intraobserver ICC: 0.985, 0.996; interobserver ICC: 0.976-0.984). CONCLUSIONS: FDG PET/CT was in high agreement with endoscopy in measuring the distance from the incisors to the proximal esophageal tumor margin. For FDG PET/CT and CT undetectable esophageal cancer, incorporation of the endoscopic measurement with PET/CT might be a way for making radiotherapy plan.

Relationship between molar incisor hypomineralization, intrapartium medication and illnesses in the first year of life.

Molar incisor hypomineralization (MIH) affects the first permanent molars and permanent incisors whose formative embryological process develops around birth and the first year of life. This study's main objective is to assess the relationship between MIH, on the one hand, with the administration during childbirth of epidural bupivacaine, intramuscular meperidine with haloperidol, synthetic intravenous oxytocin, and prostaglandins such as dinoprostone vaginally, and on the other hand, with suffered pathologies during the first year of life. Cross-sectional retrospective study was carried out on 111 children who attended dental check-ups. Oral examination was carried out to determine MIH involvement. Data on the administration of medications during delivery and the illnesses suffered by the children in the first year of life were taken from the hospital records. Significant relationship with Pearson's chi-square was found between the presence of MIH and the administration of meperidine with haloperidol intramuscularly and the vaginal administration of dinoprostone during labour. Also in children who have suffered serious infections and those who have received antibiotics in early childhood. In recent years there has been a growing trend in many countries to medicalize childbirth even above what the World Health Organization recommends. Some of the drugs used in these protocols could be involved in the appearance of dental mineralization alterations of the MIH type and this would help to explain the increase in its prevalence.

Successful management of a large mucosal fenestration at 18-months follow-up.

OBJECTIVES: Mucosal fenestrations are infrequent and often challenging to treat depending on the extent of soft and hard tissue destruction. This article presents the successful management of a relatively larger mucosal fenestration associated with complete absence of buccal bone plate in a mandibular incisor secondary to trauma-induced periapical pathosis. CLINICAL CONSIDERATIONS: After non-surgical endodontic therapy, surgery was performed for debridement of the osseous defect, root resection/shaping, connective tissue graft (CTG) placement on the affected root surface and platelet rich fibrin (PRF) in periapical osseous defect rather than use of bone graft and/or barrier membrane. Healing was uneventful, however, a small mucosal defect remained at 2 weeks follow-up. After 3 months of primary surgery, a corrective surgery was performed utilizing an "incision-free" approach i.e. tunnel technique with CTG in contrast to the contemporary flap approach. At 18 months follow-up, complete closure of the mucosal defect with a thick gingival biotype, normal sulcus depth, and good esthetic outcome were achieved. No recurrence and any clinical signs of infection or inflammation were observed. CONCLUSIONS: Based on the outcomes of present case, an early intervention utilizing the minimally invasive surgical therapy and autologous biomaterials may be considered a viable approach to treat such complex lesions. CLINICAL SIGNIFICANCE: Endodontic therapy in combination with PRF and CTG appears to provide successful outcomes in treatment of a large mucosal fenestration with periapical osseous defect.

Digital vs. Freehand Anterior Single-Tooth Implant Restoration.

Replacing a single tooth in the anterior maxilla is one of the greatest challenges in dentistry. Both functional and aesthetic results are to be strictly pursued. Planning and executing such a case through a totally digital methodology eventually guarantee many advantages, above all patient's operative and postoperative comfort. To ascertain this, a BOP analysis was performed which allowed us to evaluate soft tissues health, and more; crestal bone resorption was measured to evaluate hard tissues stability. This assumption was studied through four cases in which patients were alternatively treated with analogic and digital techniques. Four homogeneous patients were recruited. They all needed to extract one of the upper incisors, due to different clinical reasons, and then to replace it with an implant. Each patient was treated with an immediate postextractive implant which was immediately loaded, and finally, analogical and digital techniques were compared. All patients underwent a preoperative CBCT examination. After surgery, patients were checked by the surgeon after 10 days and one month to evaluate the progress of healing and to exclude any prosthetic problem. At 6 months (T1), one year (T2), and three years (T3), intraoral x-rays were performed using customized centring devices, according to the parallel beam technique. All data have been collected in a table and statistically processed; mean and standard deviation were measured. All patients entered an oral hygiene program with six months recall. Dental hygienist checked the BOP at T1, T2, and T3. At every step, similar levels of BOP were recorded. About interproximal bone loss, all patients showed an initial moderate loss (between T1 and T2), followed by stable values between T2 and T3. Despite the important limitations of a study with few cases, these results show a similar outcome comparing digital and analogical methods.

Dental changes in children with congenital Zika syndrome.

OBJECTIVE: To describe oral alterations in children with congenital Zika syndrome (CZS). METHODS: This was a case series, whose research instrument was a structured questionnaire, associated with the use of medical record data and extra and intraoral clinical examination. RESULTS: Thirty-two children were evaluated, the majority male (18/32%-56.3%), mean age 22 months (SD = 2.71). It was also observed that the majority of the patients (19/32%-59.4%) presented a low family income. All the children had a mean head circumference of 29.43 cm (SD = 1.42). Regarding the alterations, an ogival-shaped palate was observed in 14 children (43.7%), and delayed chronology of eruption was observed in 15 children (46.9%), of whom 7 children (21.9%) did not present eruption of the upper left lateral incisor (p = .0002) and upper right lateral incisor (p = .002) until the moment of analysis. Additionally, 03 children with yellowish dental pigmentation were identified in erupted teeth after the onset of phenobarbital use. Enamel hypoplasia was identified in 9 children (28.1%) and only one child with ankyloglossia. CONCLUSION: CZS may present delayed chronology of eruption, ankyloglossia, ogival-shaped palate, and enamel hypoplasia, requiring dental follow-up aimed at prevention, promotion, and rehabilitation of the health of these children.

Clinico-radiologic features of molar-incisor malformation in a case series of 38 patients: A retrospective observational study.

Molar-incisor malformation (MIM) is a recently defined dental abnormality of molar root and incisors, and introduced as one of the causes of periapical and periodontal abscess. The purpose of this study was to investigate the clinical and radiological features of MIM, with special emphasis on various medical history. A total of 38 patients with MIM were included in this study. Radiographic features and clinical data, including medical history, chief complaint, associated complications, treatment, and prognosis, were retrospectively investigated. On radiographs, the affected molars showed short, slender, underdeveloped roots and constricted pulp chambers. All affected incisors and canines exhibited dilacerated short roots, wedge-shaped defect on the cervical part of the crown. Complications included periodontal bone loss (52.6%), endodontic lesion (50.0%), and endodontic-periodontal lesion (28.9%). The medical histories of the patients with MIM indicate that almost all (94.7%) were hospitalized due to problems during the neonatal period. MIM may cause various dental problems, such as periapical and periodontal abscess and early loss of the affected teeth. The early diagnosis of MIM on radiographs and appropriate treatment will contribute to a favorable prognosis, especially for young and adolescent patients.

Spontaneous Development of Dental Dysplasia in Aged Parp-1 Knockout Mice.

Poly(ADP-ribose) polymerase (Parp)-1 catalyzes polyADP-ribosylation using NAD+ and is involved in the DNA damage response, genome stability, and transcription. In this study, we demonstrated that aged Parp-1-/- mouse incisors showed more frequent dental dysplasia in both ICR/129Sv mixed background and C57BL/6 strain compared to aged Parp-1+/+ incisors, suggesting that Parp-1 deficiency could be involved in development of dental dysplasia at an advanced age. Computed tomography images confirmed that dental dysplasia was observed at significantly higher incidences in Parp-1-/- mice. The relative calcification levels of Parp-1-/- incisors were higher in both enamel and dentin (p < 0.05). Immunohistochemical analysis revealed (1) Parp-1 positivity in ameloblasts and odontoblasts in Parp-1+/+ incisor, (2) weaker dentin sialoprotein positivity in dentin of Parp-1-/- incisor, and (3) bone sialoprotein positivity in dentin of Parp-1-/- incisor, suggesting ectopic osteogenic formation in dentin of Parp-1-/- incisor. These results indicate that Parp-1 deficiency promotes odontogenic failure in incisors at an advanced age. Parp-1 deficiency did not affect dentinogenesis during the development of mice, suggesting that Parp-1 is not essential in dentinogenesis during development but is possibly involved in the regulation of continuous dentinogenesis in the incisors at an advanced age.

Anatomical variations of maxillary lateral incisors: A comparative analysis of archaeological and modern populations from the Yucatan peninsula.

The aim of this study was to compare the prevalence of anatomical variants of maxillary lateral incisors in archaeological and modern populations from the Maya region. Both populations were derived from the state of Yucatan, Mexico. The archaeological sample consisted of human remains representing 122 individuals from the ancient Maya archaeological site of Xcambo (AD 250-700). The modern sample consisted of 475 dental models from the municipality of Tahdziú, Yucatan. The anatomical variants evaluated included microdontia, barrel-shaped incisors, and talon cusp. The prevalence of each anatomical variant for each population was calculated and compared (Fisher p < 0.05). The prevalence of anatomical variants was 15.57% (n = 19) in the archaeological sample and 14.11% (n = 67) in the modern one; the difference was not significant (p = 0.666). When compared by specific anatomical variants, a significant (p = 0.013) association was observed for microdontia: 2.45% (n = 3) in the archaeological population and 9.05% (n = 43) in the modern population. Barrel-shaped incisors (p = 0.522) and talon cusp (p = 0.466) did not exhibit significant associations. The overall prevalence of anatomical variants in the maxillary lateral incisors in this region has not changed. The prevalence of microdontia has increased over the last 1500 years, and different microevolutionary processes may be called into question for such change.

Remote Corticotomy Accelerates Orthodontic Tooth Movement in a Rat Model.

INTRODUCTION: With an increasing demand for orthodontic treatment for adult patients, orthodontic professionals are constantly seeking novel strategies and technologies that can accelerate tooth movement in order to shorten the treatment period. For instance, in recent years, the influences of different surgical techniques on orthodontic tooth movement in the ipsilateral side of surgery were intensively investigated. Here, we attempt to examine if corticotomy could also affect the rate of tooth movement in the contralateral side of the surgery by using a rodent model. MATERIALS AND METHODS: 72 eight-week-old Sprague-Dawley rats were randomly divided into three groups as follows: the Control group (orthodontic treatment devices delivered only, no tooth movement), the orthodontic tooth movement (OTM) group (orthodontic treatment devices delivered and orthodontic treatment performed), and the Corticotomy + OTM group (remote corticotomy performed, orthodontic treatment devices delivered, followed by orthodontic treatment). The surgical procedure was conducted on the right side of the maxilla at the time of appliance placement and a force of 60 g was applied between the maxillary left first molar and maxillary incisors using nickel-titanium springs to stimulate OTM. The OTM distance and speed were tracked at 3, 7, 14, and 28 days post-surgery, followed by histological and immunohistochemical assessments. RESULTS: In comparison with orthodontic treatment only, the contralateral corticotomy significantly accelerated OTM. Furthermore, animals undergoing corticotomy + OTM presented with a greater number of osteoclasts on the compression side, stronger staining of the osteogenic marker on the tension side, and higher expression of an inflammatory marker than the OTM group animals. CONCLUSION: Our current study demonstrates that remote corticotomy effectively accelerates alveolar bone remodeling and OTM. The study enriches our understanding of the regional acceleratory phenomenon (RAP) and offers an alternative strategy for accelerating OTM to shorten the orthodontic treatment period.

An unusual case of invasive cervical resorption after piezosurgery-assisted en masse retraction.

A 16-year-old patient sought orthodontic correction for profile improvement and labially inclined maxillary incisors. She had Class II malocclusion, protrusive maxillary and mandibular incisors, and increased overjet and overbite with an American Board of Orthodontics discrepancy index value of 25. She was treated with maxillary premolar extractions and miniscrew-supported en masse retraction assisted with piezoincisions. Extraction spaces (7.5 mm per side) were closed with maximum anchorage in 10 months. Total treatment time was 23 months. Twenty-seven months after debonding, a pink spot was noted at the buccocervial region of the left central incisor. Radiographic evaluation on cone-beam computed tomographic scans revealed a severe case of invasive cervical resorption on both central incisors, around which the piezosurgical cuts had been made. Treatment proceeded with a nonintervention approach and the affected teeth were reinforced with a lingual retainer.

Analysis of prevalence and diagnostic criteria of molar-incisor hipomineralization / Análisis de prevalencia y criterios diagnósticos de hipomineralización molar-incisiva

To identify the prevalence and diagnostic criteria of Molar-Incisor Hipomineralization (MIH) in the scientific literature. Materials and Methods: This is a bibliographical research conducted through the analysis of indexed articles until October 2017 in the PubMed, Web of Science and Scopus databases. The Medical Subject Headings (MESH) used were "Dental Enamel Hypoplasia" and "Molar Incisor Hypomineralization". The analysis of articles was carried out by two reviewers, who collected information independently. The following information was collected: author, year of publication, place of work (continent and country), sample calculation, sample number, age of participants, type of study, prevalence of molar-incisor hypomineralization and criteria used for diagnosis. Data were tabulated using Microsoft Excel for Windows and presented using descriptive statistics. Results: A total of 484 articles were found and 57 were included in the study. Most of the studies were conducted in Europe (35%), and 31.6% of the studies mentioned using a probability sampling. The number of study participants ranged from 99 for a study in Brazil to 3,591 in Kenya. The most frequent age was 8 years, while the predominant type of study was cross-sectional (91.2%). The prevalence varied from 0.4% to 37.3% and most studies (73.6%) employed the European Academy of Pediatric Dentistry criteria for the diagnosis of MIH. Conclusion: There is great variability in prevalence in different countries, probably due to the use of different diagnostic criteria being used, and due to different age groups and geographical variation.

Objetivo: Identificar la prevalencia y los criterios diagnósticos de la hipomineralización de incisivos molares (HIM) en la literatura científica. Materiales y métodos: Investigación bibliográfica realizada a través del análisis de artículos indexados hasta octubre de 2017 en las bases de datos PubMed, Web of Science y Scopus. Los Medical Subject Headings (MESH) utilizados fueron "Dental Enamel Hypoplasia" y "Molar Incisor Hypomineralization". El análisis de los artículos fue llevado a cabo por dos revisores, quienes recolectaron información de manera independiente. Se recopiló la siguiente información: autor, año de publicación, lugar de trabajo (continente y país), cálculo y número de muestra, edad de los participantes, tipo de estudio, prevalencia de hipomineralización molar-incisiva y criterios utilizados para el diagnóstico. Los datos se tabularon con Microsoft Excel para Windows y se presentaron con estadísticas descriptivas. Resultados: Se encontraron un total de 484 artículos y 57 se incluyeron en el estudio. La mayoría de los estudios se llevaron a cabo en Europa (35%), y el 31,6% de los estudios mencionados utilizaron una muestra probabilística. El número de participantes en el estudio varió de 99 en un estudio en Brasil a 3.591 en un estudio desde Kenia. La edad más frecuente fue de 8 años, mientras que el tipo de estudio predominante fue transversal (91,2%). La prevalencia varió de 0,4% a 37,3% y la mayoría de los estudios (73,6%) emplearon los criterios de la Academia Europea de Odontología Pediátrica para el diagnóstico de HIM. Conclusión: Existe una gran variabilidad en la prevalencia de HIM en diferentes Países, probablemente debido al uso de diferentes criterios de diagnóstico, al utilizar diferentes grupos de etarios y a la variación geográfica.

Manejo ortodóncico quirúrgico del incisivo superior ectópico / Surgical- orthodontic management of the ectopic upper incisor

La ubicación en la arcada de un incisivo superior ectópico y con diagnóstico de dilaceración, sin duda, es un gran desafío. Ya sea por su alto compromiso estético, así como también, por las maniobras biomecánicas a aplicar. La alteración de forma y ubicación ectópica del incisivo central superior, puede estar dada por un desarrollo anormal de dicha pieza sin causa aparente en el mayor porcentaje de los casos; aunque por causas obstructivas, como la presencia de diferentes patologías: quistes, odontomas, dientes supernumerarios; así como también, en un porcentaje menor, por traumatismos en los dientes temporarios

Immunohistochemical study of amelogenin binding proteins in an amelogenin point mutation mouse / Estudio inmunohistoquímico de proteínas de unión de la amelogenina en un ratón con mutación puntual de amelogenina

Amelogenin is one of the enamel matrices secreted by ameloblasts. A mutation of the amelogenin gene can cause hereditary dental enamel defects known as amelogenesis imperfecta (AI). Since lysosome-associated membrane protein-1 (LAMP-1), -3 (LAMP-3), and 78kDa glucose-related protein (Grp78) were identified as binding proteins of amelogenin, several studies have suggested the involvement of these binding proteins with the cell kinetics of ameloblasts in normal or abnormal conditions. The purpose of this study is to investigate the distribution of these amelogenin binding proteins in the ameloblast cell differentiation of mice with a point mutation of the amelogenin gene (Amelx*). The incisors of Amelx* mice had a white opaque color and the tooth surface was observed to be rough under a scanning electron microscope. Among the sequential ameloblast cell differentiation in the Amelx* mice, the shape of ameloblasts at the transition stage was irregular in comparison to those in wild-type (WT) mice. Immunostaining of Grp78 revealed that the whole cytoplasm of the transition stage ameloblasts was immunopositive for Grp78 antibody, while only the distal part of cell was positive in the WT mice. Furthermore, in the Amelx* mice, the cytoplasm of the transition stage ameloblasts was immunopositive for LAMP-1 and LAMP-3. These results suggest that Amelx* may cause the abnormal distribution of amelogenin binding proteins in the cytoplasm of ameloblasts.

La amelogenina es una de las matrices de esmalte secretadas por los ameloblastos. Una mutación del gen de amelogenina puede causar defectos hereditarios del esmalte dental conocidos como amelogénesis imperfecta (AI). Dado que la proteína de membrana asociada a lisosoma-1 (LAMP-1), -3 (LAMP-3) y la proteína relacionada con la glucosa de 78 kDa (Grp78) se identificaron como proteína de unión a amelogenina, varios estudios han sugerido la participación de estas proteínas con la cinética celular de los ameloblastos en condiciones normales o anormales. El objetivo del estudio fue investigar la distribución de LAMP-1, LAM-3 y Grp78 durante la diferenciación celular de ameloblastos de ratones con una mutación puntual del gen de amelogenina (Amelx*). Los incisivos de los ratones Amelx* presentaron un color blanco opaco y se observó en microscopio electrónico de barrido que la superficie del diente era áspera. La diferenciación celular secuencial y la forma de los ameloblastos en la etapa de transición en los ratones Amelx* fue irregular en comparación con los ratones silvestres (RS). La inmunotinción de Grp78 reveló que todo el citoplasma de los ameloblastos en etapa de transición fue inmunopositivo para el anticuerpo Grp78, mientras que solo la parte distal de la célula fue positiva en los ratones RS. Además, en ratones Amelx*, el citoplasma de los ameloblastos en etapa de transición fue inmunopositivo para LAMP-1 y LAMP-3. Estos resultados sugieren que Amelx* puede causar distribución anormal de proteínas de unión a amelogenina en el citoplasma de los ameloblastos.

The effect of cadmium exposition on the structure and mechanical properties of rat incisors.

Alterations in the structure and mechanical properties of teeth in adult Wistar rats exposed to cadmium were investigated. Analyses were conducted on two sets of incisors from female and male specimens, that were intoxicated with cadmium (n = 12) or belonged to the control (n = 12). The cadmium group was administered with CdCl2 dissolved in drinking water with a dose of 4mg/kgbw for 10 weeks. The oral intake of cadmium by adult rats led to the range of structural changes in enamel morphology and its mechanical features. A significant increase of cadmium levels in the teeth in comparison to the control, a slight shift in the colour and reduction of pigmented enamel length, higher surface irregularity, a decrease of hydroxyapatite crystals size in the c-axis and simultaneous increase in pigmented enamel hardness were observed. The extent of these changes was sex-dependent and was more pronounced in males.

Regenerative Endodontic Procedures Posttrauma: Immunohistologic Analysis of a Retrospective Series of Failed Cases.

INTRODUCTION: Regenerative endodontic procedures (REP) are a novel treatment modality to restore the function of necrotic pulp tissue via stimulation or transplantation of stem cells into the root canal. This study aimed to investigate the immunohistologic outcome of 3 extracted teeth because of sequelae of trauma and unsatisfactory REP outcomes. METHODS: Three immature permanent maxillary central incisors of 3 female patients (6-9 years) were extracted 5.5-22 months after REP. Additionally, 1 sound permanent immature central maxillary incisor of 1 of the included patients was extracted for orthodontic reasons. The teeth were immunohistologically stained with Masson's trichrome, neurofilament (NF), pan cytokeratin, dentin sialophosphoprotein, and Gram+/-. RESULTS: The REP-teeth presented intracanalar vascularized connective/mineralized reparative tissue (RT), which was less organized than the pulp tissue of the sound tooth. Moderate to considerable calcification was observed below the Portland cement used during REP. In 1 case, the RT was NF+; in the 2 other cases, the periodontal ligament and apical granuloma/papilla were NF+. All teeth were Gram+/- negative; nevertheless, inflammatory cells were present in 2 cases. The pan cytokeratin and dentin sialophosphoprotein stainings were not specific enough for 2 cases. CONCLUSIONS: This immunohistologic study of failed REP cases resulted in bacteria-free intracanalar RT and biomaterial-induced calcification. Nevertheless, the presence of inflammatory cells revealed a persistent inflammation. Hence, the clinical and radiographic signs were decisive for tooth survival and multidisciplinary outcome determination.