SHED promote angiogenesis in stem cell-mediated dental pulp regeneration.

Dental pulp, plays an indispensable role in maintaining homeostasis of the tooth. Pulp necrosis always causes tooth nutrition deficiency and abnormal root development, which leads to tooth discoloration, fracture or even loss. Our previous study showed implantation of autologous SHED could regenerate functional dental pulp. However, the detailed mechanism of the implanted SHED participating in dental pulp regeneration remains unknown. In this study, we implanted SHED in a porcine dental pulp regeneration model to evaluate the regenerative effect and identify whether SHED promoted angiogenesis in regenerated dental pulp. Firstly we verified that xenogenous SHED had the ability to regenerated pulp tissue of host in vivo. Then we found the vasculature in regenerated pulp originated from implanted SHED. In addition, stem cells were isolated from regenerated dental pulp, which exhibited good multi-differentiation properties and promoted angiogenesis in pulp regeneration process and these results demonstrated that SHED promoted angiogenesis in stem cell-mediated dental pulp regeneration.

Axonal Degeneration in Dental Pulp Precedes Human Primary Teeth Exfoliation.

The dental pulp in human primary teeth is densely innervated by a plethora of nerve endings at the coronal pulp-dentin interface. This study analyzed how the physiological root resorption (PRR) process affects dental pulp innervation before exfoliation of primary teeth. Forty-four primary canine teeth, classified into 3 defined PRR stages (early, middle, and advanced) were fixed and demineralized. Longitudinal cryosections of each tooth were stained for immunohistochemical and quantitative analysis of dental pulp nerve fibers and associated components with confocal and electron microscopy. During PRR, axonal degeneration was prominent and progressive in a Wallerian-like scheme, comprising nerve fiber bundles and nerve endings within the coronal and root pulp. Neurofilament fragmentation increased significantly during PRR progression and was accompanied by myelin degradation and a progressive loss of myelinated axons. Myelin sheath degradation involved activation of autophagic activity by Schwann cells to remove myelin debris. These cells expressed a sequence of responses comprising dedifferentiation, proliferative activity, GAP-43 overexpression, and Büngner band formation. During the advanced PRR stage, increased immune cell recruitment within the dental pulp and major histocompatibility complex (MHC) class II upregulation by Schwann cells characterized an inflammatory condition associated with the denervation process in preexfoliative primary teeth. The ensuing loss of dental pulp axons is likely to be responsible for the progressive reduction of sensory function of the dental pulp during preexfoliative stages.

Orthodontic movement in deciduous teeth.

Deciduous teeth exfoliate as a result of apoptosis induced by cementoblasts, a process that reveals the mineralized portion of the root while attracting clasts. Root resorption in deciduous teeth is slow due to lack of mediators necessary to speed it up; however, it accelerates and spreads in one single direction whenever a permanent tooth pericoronal follicle, rich in epithelial growth factor (EGF), or other bone resorption mediators come near. The latter are responsible for bone resorption during eruption, and deciduous teeth root resorption and exfoliation. Should deciduous teeth be subjected to orthodontic movement or anchorage, mediators local levels will increase. Thus, one should be fully aware that root resorption in deciduous teeth will speed up and exfoliation will early occur. Treatment planning involving deciduous teeth orthodontic movement and/or anchorage should consider: Are clinical benefits relevant enough as to be worth the risk of undergoing early inconvenient root resorption?

Orthodontic movement in deciduous teeth

Deciduous teeth exfoliate as a result of apoptosis induced by cementoblasts, a process that reveals the mineralized portion of the root while attracting clasts. Root resorption in deciduous teeth is slow due to lack of mediators necessary to speed it up; however, it accelerates and spreads in one single direction whenever a permanent tooth pericoronal follicle, rich in epithelial growth factor (EGF), or other bone resorption mediators come near. The latter are responsible for bone resorption during eruption, and deciduous teeth root resorption and exfoliation. Should deciduous teeth be subjected to orthodontic movement or anchorage, mediators local levels will increase. Thus, one should be fully aware that root resorption in deciduous teeth will speed up and exfoliation will early occur. Treatment planning involving deciduous teeth orthodontic movement and/or anchorage should consider: Are clinical benefits relevant enough as to be worth the risk of undergoing early inconvenient root resorption?.

O dente decíduo é esfoliado graças à apoptose em seus cementoblastos, que desnuda a parte mineralizada da raiz e atrai os clastos. A rizólise é lenta, pois faltam mediadores em quantidade para acelerar o processo, mas ela se acelera e unidireciona quando se aproxima um folículo pericoronário de dente permanente rico em EGF e outros mediadores da reabsorção óssea - os responsáveis pelas reabsorções óssea na erupção e dentária decídua na rizólise e esfoliação. Se houver movimentação ortodôntica ou ancoragem em dentes decíduos, aumenta-se, também, o nível local desses mesmos mediadores, devendo-se estar bem consciente de que haverá uma aceleração da rizólise e, em decorrência, uma antecipação de sua esfoliação. No planejamento de casos em que dentes decíduos estejam envolvidos na movimentação ortodôntica e/ou ancoragem, deve-se ponderar: o benefício clínico para o paciente será relevante, a ponto de valer o risco de uma rizólise abreviada e inconveniente?.

Evaluation of marginal alveolar bone height for early detection of periodontal disease in pediatric population: clinical and radiographic study.

OBJECTIVES: To establish a normal range for the radiographic distance between cementoenamel junction and alveolar bone crest and the factors affecting distances for the early assessment of periodontal disease in Dravidian pediatric population. METHODS: Fifty children aged 6 to 8 years were selected based on inclusion and exclusion criteria. Clinical and radiographic examination was performed. All the surfaces were examined starting from the distal surface of primary canine to the mesial surface of first permanent molar. The various risk factors like plaque, calculus, proximal caries, restoration and bleeding on probing were recorded. A pair of bitewing radiographs was taken for each child. Bitewing radiographs were traced and analyzed. RESULTS: It showed that CEJ-ABC distance in primary teeth is about 1 ± 0.5 mm. In the permanent teeth, it was found to be 0.6 ± 0.5 mm in 6 to 8 years age group. CEJ-ABC distance was also affected by different variables like physiologic (eruption and exfoliation) and pathologic factors (plaque, calculus, dental caries, restorations, stainless steel crowns, bleeding on probing and probing depth). CONCLUSION: CEJ-ABC distances greater than 2.5 mm should be considered under recall and follow-up. Children and adolescents susceptible to periodontal disease should be identified by radiographic means as early as possible in order to prevent the advance of an otherwise possibly destructive disease. The concept of oral health examination and treatment must include examination of the periodontal status of the patient.

Use of the passive lower lingual arch in the management of anterior mandibular crowding in the mixed dentition.

Leeway space preservation in the mixed dentition is a well-documented method of space management. In the mandibular arch it may be saved for utilisation in the correction of minor anterior crowding by the placement of a passive lower lingual arch (LLA) during the transition from the mixed dentition to the permanent dentition.

Clinical and SEM characterization of prolonged retention of a primary tooth with pulpectomy.

Root canal filling with zinc oxide-eugenol (ZOE) paste following primary tooth pulpectomy is a common practice in pediatric dentistry. This material offers high clinical and radiographic success rates. In some cases, however, it is not resorbed along with the root of the primary tooth. The aim of this study was to describe a case of prolonged retention of a primary maxillary incisor that was subjected to pulpectomy and filled with ZOE paste in order to characterize the aspects of root resorption using scanning electron microscopy.

Autotransplantion of a displaced mandibular second premolar to its normal position.

The patient was a 13-year-old Korean girl who had a displaced mandibular second premolar. She was reluctant to undergo a lengthy orthodontic treatment and opted instead for transplantation of the premolar to its usual site. On the basis of computed tomography, a replica tooth model was manufactured to shorten the extraoral time, and a root canal treatment was performed because root formation was complete. No negative signs or symptoms were found during a 3-year follow up. Autotransplantation for this patient obviated the need for orthodontic traction and prosthetic therapy.

The effect of GIC-brand on the survival rate of proximal-ART restorations.

BACKGROUND: Laboratory studies show diverse behaviour of different brands of glass-ionomer cements (GIC). AIM: This study investigated the clinical performance [survival rate (SR)] of three GIC brands applied to proximal atraumatic restorative treatment (ART) restorations. Additionally, the SR of the tooth was evaluated. DESIGN: Proximal cavities of 262 primary molars were restored. The patients had been randomly allocated to two operators and three GIC brands: Fuji IX, Hi-Dense, and Maxxion R. Restorations were evaluated after 1, 6, 12, 18, 24, 30, and 36 months. Failed restorations were, if possible, repaired or replaced. Linear regression analyses were used to evaluate the effect of GIC brand, operator, and surface of restoration. Kaplan-Meier survival analysis and log-rank test were performed for both restoration survival and tooth survival (α = 5%). RESULTS: After 3 years, 82.4% of the restorations were evaluated. The SR of the restorations was 24.4%, and there was no difference among GIC brands (log-rank test, P = 0.6). In the first 18 months, a significant operator effect and significantly higher failures in distal surfaces were found. The SR of the tooth was 81.7%. CONCLUSIONS: The SR of proximal ART restorations was relatively low when compared with the SR of the tooth. There are no differences in the performance among the GIC brands used in the study.

Current concepts in hypophosphatasia: case report and literature review.

BACKGROUND. Hypophosphatasia (HP) is characterized by defective mineralization of bone and teeth because of deficient alkaline phosphatase activity. There are generally six recognized clinical forms, of which the most severe is often lethal prenatally or early in life. In milder forms, such as odontohypophosphatasia (OHP), premature exfoliation of primary teeth may be the only clinical manifestation. CASE REPORT. A 20-month-old girl was referred to the Specialist Paediatric Salaried Dental Service within the Harrogate and District NHS Foundation Trust with mobility of tooth numbers 71 and 81. Clinical examination revealed grade III mobile 71 and 81, with minimal gingival inflammation and plaque deposits. There were no other dental findings and no significant medical history. Tooth numbers 71 and 81 exfoliated prematurely with no evidence of root resorption, shortly after presentation. Haematological and urinary investigations showed no abnormalities. Histological examination showed a complete absence of cementum. A diagnosis of OHP was made. After 10 months of dental follow-up, no further teeth have increased mobility. CONCLUSION. Odontohypophosphatasia should be included as a differential diagnosis in children presenting with early loss of primary teeth. The dentist may be the first health care professional to whom the patient presents.

Degree of root resorption after root canal treatment with iodoform-containing filling material in primary molars.

OBJECTIVE: To compare the degree of root resorption in endodontically treated primary molars with that of homologous teeth without root canal treatment. METHOD AND MATERIALS: A retrospective study was carried out comprising 105 records of children who had received root canal treatment in a primary molar. Mean age at the time of treatment was 7.0 ± 1.4 years. Inclusion criteria included one endodontically treated primary molar and a homologous primary molar with no root canal treatment on the other side of the mouth. All teeth were treated by the same operator in the same way using the same iodoform-containing root canal filling material. The degree of root resorption was compared by radiographic evaluation 12 or more months posttreatment. RESULTS: The degree of root resorption on the final follow-up radiograph in the endodontically treated primary molars was significantly higher (P < .05) than the degree of root resorption in the homologous teeth. The degree of root resorption was higher in boys than in girls. No statistical significance was found between the degree of root resorption and the age at the time of treatment in either the root canal-treated teeth or the homologous teeth. Follow-up radiographs demonstrated a higher degree of root resorption in the root canal treated teeth than in the homologous teeth, regardless of the type of treatment performed on the homologous side. CONCLUSION: Root canal treatment performed with iodoform-containing root canal filling material accelerates root resorption in root canal-treated primary molars compared with homologous teeth without endodontic treatment. Clinicians should be aware that endodontically treated teeth will probably shed before homologous ones that are not root canal treated.

Hypoplastic root cementum and premature loss of primary teeth in Coffin-Lowry syndrome: a case report.

BACKGROUND: Coffin-Lowry syndrome (CLS) is a rare genetic disorder. The syndrome presents with psychomotor retardation, short stature, skeletal deformations, digit abnormalities, and distinctive facial features. Oral and dental findings in CLS are common and they include thick prominent lips, high palate, midline lingual furrow, hypodontia, microdontia, delayed eruption, and early tooth loss. Only one earlier case suggesting hypoplastic root cementum as cause for primary loss of teeth in CLS has been published. CASE REPORT: This case describes a 3-year-old boy with premature loss of primary incisors without preceding root resorption. In addition to the dental findings, the boy had several general signs and symptoms and the dental findings together with the other characteristics led to the clinical diagnosis of CLS, which later was genetically verified. Histological analysis of an extracted primary incisor showed hypoplastic root cementum. CONCLUSION: Hypoplastic root cementum may explain early tooth loss in CLS. As early loss of primary teeth is rare, especially when there is no previous root resorption, the individual is likely to seek dental care. Thus, the dentist may play an important role in assisting in the diagnosing of CLS.

Treatment outcomes of pulpotomy in primary molars using two endodontic biomaterials. A 2-year randomised clinical trial.

AIM: To compare the treatment outcomes of calcium-enriched mixture (CEM) cement and mineral trioxide aggregate (MTA) as pulp dressing biomaterials in vital pulpotomy of carious primary molars. STUDY DESIGN: split-mouth randomised clinical trial. MATERIALS AND METHODS: Forty children aged 4-8 years with 2 carious teeth requiring pulpotomy were selected and randomly assigned to MTA (n = 40) or CEM (n = 40) groups. After coronal pulp removal, the remaining radicular pulp was covered with an appropriate biomaterial; the teeth were then permanently restored. Clinical/radiographic success/failures were blindly evaluated at 6-, 12- and 24-month follow-ups. STATISTICS: the recorded data were analyzed with McNemar test and GEE. RESULTS: A total of 36, 33 and 35 patients were available for 6-, 12- and 24-month follow-ups, respectively. At the 12-month follow-up only one and three teeth in the CEM and MTA groups had pathologic external root resorption, respectively. The resorbed teeth were then missed due to extraction/exfoliation at the 24-month follow-up; all other treated teeth were sign/symptom-free. Overall, clinical and radiographic outcomes in both MTA/CEM groups were comparable at the three follow-ups without significant differences. Time had no significant effect on the success. CONCLUSION: MTA and CEM demonstrated favourable treatment outcomes for pulpotomy of carious primary molars; CEM may be an effective pulp dressing biomaterial.

A retrospective study of a modified 1-minute formocresol pulpotomy technique part 2: effect on exfoliation times and successors.

PURPOSE: The purposes of this study were to evaluate the: effect of a 1-minute application of full-strength Buckley's formocresol with concur- rent hemostasis using the medicated cotton pledget in human primary teeth on their successors; and exfoliation times compared to the contralateral nonpulpotomized tooth. METHODS: Using a retrospective chart review, clinical and radiographic data were available for 557 primary molars in 320 patients. RESULTS: There was no difference between treated and control teeth in the number of enamel defects of succedaneous teeth (P<.45). Approximately 66% exfoliated at the same time as their contralateral counterpart and approximately 29% exfoliated earlier (P<.001). CONCLUSIONS: This 1-minute technique showed a tendency toward early exfoliation, but no effect on clinical management, and no increase in incidence of defects on succedaneous teeth was observed. The 1-minute full-strength formocresol technique may be considered an acceptable alternative to the 5-minute formocresol pulpotomy.

Early identification and management of mandibular canine ectopia.

Mandibular canine impaction and transmigration have serious consequences for the patient, as removal of the tooth or teeth in question is often the only solution. The loss of one or both mandibular canines complicates orthodontic treatment. Early warning signs of mandibular canine ectopia are explored in this paper as well as how to assess the potential for displacement, impaction and/or transmigration. This paper highlights the value of interceptive treatment once the early signs of an aberrant mandibular canine have been detected.

New teeth from old: treatment options for retained primary teeth.

Retention of primary teeth beyond their expected exfoliation date is encountered relatively frequently. Most commonly this is due to absence of the permanent successor. In this article patient assessment and the restorative treatment options are discussed with particular emphasis on retention of the primary tooth/teeth in the medium to long-term. The restorative techniques that may be used to improve aesthetics and function of retained primary teeth are illustrated. Consideration of this minimally invasive approach is commended in such cases.

Pulpotomy of human primary molars with MTA and Portland cement: a randomised controlled trial.

OBJECTIVE: This study compared the clinical and radiographic effectiveness of mineral trioxide aggregate (MTA) and Portland cement (PC) as pulp dressing agents in carious primary teeth. METHODOLOGY: Thirty carious primary mandibular molars of children aged 5-9 years old were randomly assigned to MTA or PC groups, and treated by a conventional pulpotomy technique. The teeth were restored with resin modified glass ionomer cement. Clinical and radiographic successes and failures were recorded at 6, 12, 18 and 24-month follow-up. RESULTS: All pulpotomised teeth were clinically and radiographically successful at all follow-up appointments. Six out of 15 teeth in the PC group and five out of 14 teeth in the MTA group exfoliated throughout the follow-up period. No statistically significant difference regarding dentine bridge formation was found between both groups throughout the follow-up period. As far as pulp canal obliteration is concerned, a statistically significant difference was detected at 6-month follow-up (p <0.05), since the beginning of mineralised material deposition could be radiographically detected in 100% and 57.14% of the teeth treated with PC and MTA, respectively. CONCLUSIONS: PC may serve as an effective and less expensive MTA substitute in primary molar pulpotomies. Further studies and longer follow-up assessments are needed.

Clinical applications of orthodontic microimplant anchorage in craniofacial patients.

Microimplant anchors, also known as temporary anchorage devices, mini- and micro-screws, have been used to enhance orthodontic anchorage for difficult tooth movements. Here, the authors describe how microimplants can be used to help treat craniofacial patients by supporting distraction osteogenesis procedures, maxillary protraction procedures, cleft segment expansion and stabilization, and tooth movement into narrow alveolar cleft sites. While most craniofacial patients are treated without microimplants, it would be worthwhile to identify which cases could benefit from microimplant anchorage. As an adjunct to orthodontic treatment, the microimplant offers a potential method for solving troublesome orthodontic and surgical problems such as guiding distraction procedures with orthodontics when primary teeth are exfoliating, addressing residual maxillary cants after vertical distraction osteogenesis of a ramus, stabilizing an edentulous premaxilla, and moving teeth into atrophic alveolar ridges. These cases are presented to open a dialogue on their possible uses in craniofacial patients.

[Correlation between the lower first permanent molar axis and the premature loss of temporary molars]. / Relatia dintre axul molarului prim permanent mandibular si pierderea prematura a molarilor temporari.

UNLABELLED: The aim of our study was to determine the impact of premature loss of temporary molars upon the longitudinal axis of the first permanent molar. MATERIAL AND METHOD: The study sample was formed by 94 orthopanthomografies of child patients with premature loss of lower temporary molars (first or second) after clinical eruption of the first permanent molar. All panoramic radiographs have been realized with the same panoramic unit with 1.4% magnification coefficient and were analyzed using a standardized technique of tracing the images of teeth and bone on matte acetate paper. It was evaluated the angle between longitudinal axis of first permanent lower molar and occlusal plane. RESULTS: It was observed that premature loss of lower second deciduous molar modifies greater the vertical axis of first permanent molar (between 61 degrees and 79 degrees) then premature loss of first lower primary molar. This is perhaps because the loss of space in the case of premature exfoliation of first primary molar is due more to distal drift of canine then mesial drift of molars. CONCLUSION: The drift to mesial of first permanent molar is more accentuated proportional with the age at which appeared premature loss and so it is loss of leeway space.