Regenerative endodontic therapy for external inflammatory lateral resorption following traumatic dental injuries: Evidence assessment of best practices.

BACKGROUND: External inflammatory lateral resorption (EILR) following dental trauma is a severe complication that can lead to significant root loss and tooth extraction. OBJECTIVE: The aim of this project was to review current evidence in the literature on regenerative endodontic therapy (RET) for EILR following traumatic injuries and assess the best treatment practices. METHODS: Publications appearing in PubMed, from January 1, 2001 to January 9, 2022 were studied. Inclusion criteria were: (a) Publications in English; (b) Publications on RET and EILR; (c) Teeth subjected to dental trauma; and (d) Presence of intracanal bleeding and blood clots. Exclusion criteria were: (a) Conference proceedings; (b) Lectures; (c) Abstracts; and (d) Letters to editor; (e) Non-English publications. RESULTS: 355 publications were analysed. Nine met all inclusion criteria. In 10 (58.8%) teeth, triple antibiotic paste was used for an average of 26 days. Double antibiotic paste was used in 3 (17.6%) teeth for an average of 14 days. In 3 (17.6%) cases, calcium hydroxide (Ca(OH)2 ) was used for 14 days and negative pressure irrigation was applied once on 1 (6%) tooth. DISCUSSION: Using RET to treat EILR has some advantages compared to long term CA(OH)2 dressing. RET requires shorter dressing time compared to CA(OH)2 . This can significantly improve patient compliance. Additionally, in immature teeth, RET helps to arrest root resorption leading to continued root maturogenesis and revascularization. It is recommended that a meticulous follow-up should be conducted when RET is performed to assure early detection of treatment failure. CONCLUSIONS: RET appears to be a good treatment modality producing biologic repair and improving prognosis in cases of EILR in post-traumatic tooth/pulp injuries. The key limitation of this study is that all publications included were either case reports or case series that usually tend to report successful outcome.

Traumatismos bucodentales en la práctica del rugby: a propósito de un caso / Oral trauma in rugby practice: about a case

Introducción: La participación en el rugby se ha visto incrementada con el paso de los años, especialmente en países donde la práctica de este deporte no era habitual, lo que ha arrojado como consecuencia un aumento en la incidencia de lesiones, dada la naturaleza de alto impacto del mismo. Diversos estudios epidemiológicos han evaluado la incidencia de traumatismos bucodentales como consecuencia de accidentes deportivos, en los que se hace referencia a las fracturas dentarias como aquellas más comúnmente producidas dentro de la práctica de este tipo de deportes. Descripción del caso clínico: Se presenta el caso clínico de un paciente varón de 18 años de edad, sin antecedentes médicos de interés, remitido al servicio de Cirugía Bucal del Hospital Viamed Virgen de la Paloma de Madrid, quién presentaba una lesión de tejidos blandos, además de luxación palatina del sector dentario anterosuperior, como consecuencia de un traumatismo durante un partido de rugby, para el cual se prescribió tratamiento farmacológico combinado con una ferulización, permitiéndose así la cicatrización espontánea de los tejidos. Discusión y conclusiones: Se observa una alta incidencia de lesiones producidas durante la práctica del rugby debido al escaso equipamiento protector usado por los jugadores, donde la cara y sus tejidos blandos constituyen las zonas con mayor frecuencia de afectación, pudiendo considerarse como el deporte de alto impacto con mayor prevalencia de lesiones de cabeza y cuello. (AU)

Introduction: Participation in rugby has increased over the years, especially in countries where the practice of this sport was not common, which has resulted in an increase in the incidence of injuries given its high-impact nature. Various epidemiological studies have evaluated the incidence of oral trauma as a result of sports accidents, in which dental fractures are referred to as those most commonly produced within the practice of this type of sports. Description of the clinical case: We present the clinical case of an 18-yearold male patient, with no relevant medical history, referred to the Oral Surgery Service of the Virgen de la Paloma Viamed Hospital in Madrid, who presented a soft tissue lesion in addition to a palatal dislocation of the dental sector anterosuperior as a result of trauma during a rugby match, for which drug treatment combined with splinting was prescribed, thus allowing spontaneous tissue healing. Discussion and conclusions: A high incidence of injuries produced during rugby practice is observed due to the scarce protective equipment used by the players, where the face and its soft tissues constitute the areas with the highest frequency of affectation and can be considered as the high-impact sport with the highest prevalence of head and neck injuries. (AU)

Tratamiento no quirúrgico de lesión periapical de gran tamaño: Reporte de caso / Non-surgical Therapeutics of large size periapical injury: Clinical case report

Resumen Se describe un caso clínico sobre una mujer de 21 años de edad la cual sufrió trauma dental a los 6 años que comprometió al incisivo superior izquierdo lo cual con el tiempo generó o se formó una gran lesión periapical en esta región. Radiográficamente se observa la formación incompleta de la raíz, las paredes del conducto radicular delgadas, y una extensa lesión periapical. Se realizó el desbridamiento químico-mecánico con limas K y se ejecutó la desinfección del conducto radicular con clorhexidina al 2%. El conducto se deja medicado con hidróxido de calcio (Vitapex®), el cual se reemplaza periódicamente con dicho material hasta los nueve meses, finalmente se obtura con Biodentine®. Se da seguimiento al caso a través de cuatro años, pasando por blanqueamiento interno, carilla de resina hasta llegar a poste intra radicular con corona completa de porcelana en lo concerniente al aspecto estético. En cuanto a la lesión periapical de gran tamaño, se llega a observar por medio de tomografías, disminución de la lesión al mínimo y genera cicatrización ósea. En relación con la observación clínica hay desaparición de la fístula y ausencia de sintomatología.

Abstract This report describes a clinical case involving a 21-year-old woman, who suffered dental trauma at age 6, compromising left tooth 2.1. On time she developed a large periapical injury in this area. Radiographically, incomplete root formation, thin walls of the root canal, and extensive periapical damage is clearly shown. Chemo- mechanical debridement was performed with K files and disinfection of the root canal using 2% chlorhexidine. The root canal was left medicated with calcium hydroxide (Metapex), which was replaced periodically until 9 months. Finally, the root canal was completely sealed with Biodentine. The case had a follow up for over four years and concerning esthetical aspects, through this period of time an internal whitening, resin veneer, intra radicular post and complete crown were provided. Regarding the considerable periapical injury, tomography shows that it has been drastically reduced and generated bone healing. Clinical observations also show that the fistula and symptomatology disappeared.

Community pharmacy staff oral health training, training needs and professional self-efficacy related to managing children's dental problems.

OBJECTIVES: Few studies have explored the oral health training needs and professional self-efficacy (PSE) in both pharmacy support staff and pharmacists related to managing children's dental problems. This study assessed community pharmacy staff perceptions of their (i) training experiences and interests; (ii) PSE; and (iii) whether this was influenced by the pharmacy being part of a minor ailment scheme (MAS), where staff could directly offer advice and issue prescription medications without patients seeing a doctor. METHODS: All of the 1851 community pharmacies across London, UK, were invited to participate in an online questionnaire. Staff rated their prior training, perceived need for further training and confidence in giving parents advice related to three dental problems in children (dental pain, mouth ulcers and dental trauma). Information was collected about staff roles and whether the pharmacy was a MAS. KEY FINDINGS: From 752 community pharmacies, 846 community pharmacy staff participated. Positive experiences of training were variable but interest in further training for all three dental problems was high. Pharmacy support staff had significantly lower PSE scores than pharmacy professionals (P = 0.009). A significant interaction showed that pharmacy staff who had poorly rated prior training on advising parents about managing their child's dental pain and who did not work in a MAS had lower PSE scores than staff who had highly rated training and who worked in a MAS (P = 0.02). CONCLUSIONS: Minor ailment scheme pharmacies may be an optimal environment for frontline pharmacy support staff to develop higher PSE when combined with good quality oral health training.

European Society of Endodontology position statement: the use of antibiotics in endodontics.

This position statement represents a consensus of an expert committee convened by the European Society of Endodontology (ESE) on Antibiotics in Endodontics. The statement is based on current scientific evidence as well as the expertise of the committee. The goal is to provide dentists and other healthcare workers with evidence-based criteria for when to use antibiotics in the treatment of endodontic infections, traumatic injuries of the teeth, revascularization procedures in immature teeth with pulp necrosis, and in prophylaxis for medically compromised patients. It also highlights the role that dentists and others can play in preventing the overuse of antibiotics. A recent review article provides the basis for this position statement and more detailed background information (International Endodontic Journal, 2017, https://doi.org/10.1111/iej.12741). Given the dynamic nature of research in this area, this position statement will be updated at appropriate intervals.

Promotion of natural tooth repair by small molecule GSK3 antagonists.

The restoration of dentine lost in deep caries lesions in teeth is a routine and common treatment that involves the use of inorganic cements based on calcium or silicon-based mineral aggregates. Such cements remain in the tooth and fail to degrade and thus normal mineral volume is never completely restored. Here we describe a novel, biological approach to dentine restoration that stimulates the natural formation of reparative dentine via the mobilisation of resident stem cells in the tooth pulp. Biodegradable, clinically-approved collagen sponges are used to deliver low doses of small molecule glycogen synthase kinase (GSK-3) antagonists that promote the natural processes of reparative dentine formation to completely restore dentine. Since the carrier sponge is degraded over time, dentine replaces the degraded sponge leading to a complete, effective natural repair. This simple, rapid natural tooth repair process could thus potentially provide a new approach to clinical tooth restoration.

Dental Trauma in a Pediatric Emergency Department Referral Center.

OBJECTIVE: The purpose of this study was to describe dental and associated oral injuries in a pediatric population that presents to an emergency department. METHODS: We performed a retrospective study and identified children from January 2007 to September 2011. Charts were reviewed for any subject, age from newborn to younger than 19 years, based on International Classification of Diseases, Ninth Revision codes for any dental or oral injury. Data abstraction included demographics, time of day of presentation, location and identification of tooth (s) injured, management, and disposition. RESULTS: We identified 108 children with dental and if present, associated oral injuries. The median age was 12.3 years, the most common tooth injured were the primary (25.9%) or permanent (62%) upper central incisors, and the majority of subjects presented in the afternoon (mean time was 3:50 PM, SD ±24 minutes). A large proportion of dental injuries occurred in patients with permanent dentation (62%) and half of all children had more than 1 tooth injury. The majority of children (75%) were evaluated by either pediatric dental, oral surgery, or otolaryngology services, whereas 3.7% of the cases required multiple services. Twenty-five percent of children had an associated jaw fracture. Eighty-three percent of children were discharged home, of those, 49.1% were prescribed opioids, and 38.3% oral antibiotics. CONCLUSIONS: Emergency departments are often relied upon to evaluate and treat simple and complex dental and oral injuries. The ability to use a multidisciplinary team to manage pediatric oral and dental trauma is essential for care.

Evolución clínica de dientes permanentes traumatizados: Policlínico Taguasco. 2010-2011 / Clinical evolution of permanent traumatized teeth: Polyclinic Taguasco. 2010-2011

El aumento progresivo de los traumatismos dentoalveolares su inestable evolución a mediano y corto plazo motivó la realización de esta investigación. Objetivo: identificar la evolución en el tratamiento de lesiones traumáticas en dientes permanentes en pacientes que acudieron a consulta de urgencia durante el periodo comprendido de julio a diciembre del 2010 y evolucionados de agosto hasta diciembre del 2011. Metodología: se realizó un estudio descriptivo transversal. La población de estudio que coincide con la muestra fueron 45 pacientes con traumatismo en dientes permanentes. Las variables: edad, clasificación de las lesiones traumáticas, tratamiento, periodicidad en la evolución, la evolución clínica anual de los dientes complicados y la evolución anual de forma general. Resultados: el grupo de 8-11 mostró cifras más altas y las fracturas no complicadas de la corona fueron las más numerosas. El recubrimiento pulpar fue el tratamiento de urgencia más usado. Se encontraron signos de afección clínica en la evolución anual de algunos pacientes. Los pacientes que mantuvieron una periodicidad completa en su tratamiento evolucionaron de forma satisfactoria. Conclusiones: los pacientes que tuvieron fracturas más complicadas presentaron signos de afección clínica y aquellos que mantuvieron una periodicidad en el tratamiento tuvieron una evolución satisfactoria(AU)

The progressive increasement of dentoalveolar traumas, its unsteady evolution in middle and short term motivated the realization of this investigation. To identify the evolution of traumatic lesions in permanent teeth in patients who came to the emergency room from July to December 2010 and evolved from August to December 2011. Methodology: a transversal descriptive study was carried out. The study population which coincides with the sample was 45 patients with trauma in permanent teeth. The variables: age classification of traumatic lesions, treatment, evolution, yearly clinical evolution. Results: the group 8 to 11 showed higher numbers and the non-complicated fractures of the crown were the most frequent. The pulpar covering was the most used emergency treatment. Signs of clinical affectations in the yearly evolution of some patients were found. The patients with a complete follow up of the treatment evolved satisfactorily. Conclusions: The patients who had more complicated fractures showed signs of clinical affectations(AU)

Properties and applications of calcium hydroxide in endodontics and dental traumatology.

Calcium hydroxide has been included within several materials and antimicrobial formulations that are used in a number of treatment modalities in endodontics. These include, inter-appointment intracanal medicaments, pulp-capping agents and root canal sealers. Calcium hydroxide formulations are also used during treatment of root perforations, root fractures and root resorption and have a role in dental traumatology, for example, following tooth avulsion and luxation injuries. The purpose of this paper is to review the properties and clinical applications of calcium hydroxide in endodontics and dental traumatology including its antibacterial activity, antifungal activity, effect on bacterial biofilms, the synergism between calcium hydroxide and other agents, its effects on the properties of dentine, the diffusion of hydroxyl ions through dentine and its toxicity. Pure calcium hydroxide paste has a high pH (approximately 12.5-12.8) and is classified chemically as a strong base. Its main actions are achieved through the ionic dissociation of Ca(2+) and OH(-) ions and their effect on vital tissues, the induction of hard-tissue deposition and the antibacterial properties. The lethal effects of calcium hydroxide on bacterial cells are probably due to protein denaturation and damage to DNA and cytoplasmic membranes. It has a wide range of antimicrobial activity against common endodontic pathogens but is less effective against Enterococcus faecalis and Candida albicans. Calcium hydroxide is also an effective anti-endotoxin agent. However, its effect on microbial biofilms is controversial.

Successful application of atelocollagen for treatment of perforated teeth.

OBJECTIVE: Cervical or furcal root perforation is a serious clinical problem and one of its treatment modalities is perforation repair with composite resin. However, many cases still progress in inevitable extraction. When primary teeth are affected, early tooth loss can cause problems related to the eruption space for the permanent successors. The aim of the present study was to evaluate a novel clinical treatment method for perforated teeth. STUDY DESIGN: Atelocollagen was applied to perforated furcal and cervical areas of 13 primary teeth in 13 children aged 4-9 years and 8 permanent teeth in 8 adults aged 35-69 years after debridement with an electric knife. Thereafter the final restorations were performed after confirming good tooth conditions. Clinical evaluations were performed at follow-up examinations at approximately 3-month intervals. RESULTS: None of the treated primary teeth showed any clinical problems throughout the observation period, with eruption of the permanent successors noted in 7 cases. In the permanent teeth, no clinical problems were identified in any of the cases during follow-up periods of 10-60 months. CONCLUSION: This novel method may enable preservation of perforated primary teeth for a longer duration.

Effects of root canal irrigants on the push-out strength and hydration behavior of accelerated mineral trioxide aggregate in its early setting phase.

INTRODUCTION: The purpose of this study was to evaluate the effects of endodontic irrigants on the push-out strength and hydration behavior of accelerated mineral trioxide aggregate (MTA) in its early setting phase. METHODS: In an in vitro perforation model, MTA with or without 10% CaCl(2) was condensed and allowed to initial set for 10 minutes. The samples were divided into four groups (n = 10) to be immersed into either 3.5% sodium hypochlorite (NaOCl) or 2% chlorhexidine gluconate (CHX) for 30 minutes and then allowed to set for 48 hours. In the control group, a wet cotton pellet was placed over MTA. The maximum force applied to the set MTA mixture before dislodgement was recorded. Irrigant-treated surfaces were examined using a scanning electron microscope (SEM). Chemical elements of these surfaces were also analyzed by energy dispersive x-ray spectroscope (EDS). RESULTS: The push-out strength of group A1 (NaOCl-treated accelerated MTA) was the highest of all groups. When compared with nonaccelerated MTA, CaCl(2)-accelerated MTA showed significantly higher push-out strength (p < 0.05). NaOCl-treated groups showed significantly higher push-out strength than CHX-treated groups (p < 0.05). Scanning electron microscopic examination and EDS analysis showed that the formation of calcium hydroxide crystals on accelerated MTA exposed to NaOCl was increased compared with those of the control group. CONCLUSION: These findings imply that the use of accelerated MTA under the NaOCl irrigation was effective in perforation repair without altering its hydration behavior even in the early setting phase.

Calcitonin, sodium alendronate and high intensity laser in the treatment of traumatized teeth: a preliminary study.

The aim of this study was to evaluate the influence of erbium:yttrium-aluminum-garnet (Er:YAG) laser compared with traditional treatment on dentin permeability to calcitonin and sodium alendronate. Forty bovine roots were sectioned and divided into eight groups. Groups 1 and 2 (G1/G2) were immersed in saline solution; G1T/G2T were immersed in ethylene diamine tetra-acetic acid plus sodium lauryl ether sulfate (EDTA-T) and sodium hypochlorite (NaOCl); G1I/G2I were irradiated with Er:YAG laser (2.94 microm, 6 Hz, 40.4 J/cm(2)); G1TI/G2TI were immersed in EDTA-T, NaOCl and subjected to Er:YAG irradiation. After 4 h the radioactivity of the saline solution was measured. Statistical analysis revealed a significant difference (P < 0.05) when the groups treated with EDTA-T and NaOCl followed by Er:YAG laser irradiation were compared with the groups treated with EDTA-T only and with the groups that received no treatment. Er:YAG laser associated with traditional procedures significantly increased the diffusion of calcitonin and sodium alendronate through dentin. All groups showed calcitonin and sodium alendronate diffusion.

Dexamethasone effects on Na(v)1.6 in tooth pulp, dental nerves, and alveolar osteoclasts of adult rats.

Dexamethasone causes extensive physiologic reactions including the reduction of inflammation and pain. Here, we asked whether it also affected dental or periodontal cells or dental innervation by altering voltage-gated sodium channel Na(v)1.6 immunoreactivity (IR) or neural synaptophysin. Daily dexamethasone (0.2 mg/kg) given for 1 week to rats caused 12-fold increased intensity of Na(v)1.6-IR in dendritic pulpal cells of normal molars and incisors compared with vehicle treatment. These cells also co-localized monocyte (ED-1) or dendritic cell (CD11b/Ox42) markers, and their location in molars expanded during dexamethasone treatment to include deeper pulp. Furthermore, dexamethasone caused a 10-fold decrease in the number of Na(v)1.6-immunoreactive multinucleate osteoclasts along the alveolar bone of molar root sockets. No changes occurred for neural Na(v)1.6 at axonal nodes of Ranvier, even though IR for calcitonin gene-related peptide was greatly decreased, as expected, and neural synaptophysin-IR was decreased 59% by dexamethasone. At 4 days after tooth injury, pulpal vasodilation and increased Na(v)1.6-immunoreactive pulp cells were similar for all groups. Thus, dexamethasone changes dental pulp cell and alveolar osteoclast Na(v)1.6-IR in normal teeth, but different mechanisms occur after tooth injury when tissue reactions were similar for dexamethasone- and vehicle-treated rats. Steroid-induced alterations of dental pain and inflammation coincide with altered exocytic capability in dental nerve fibers as shown by synaptophysin-IR and with altered pulp cell Na(v)1.6-IR and osteoclast number, but not with any changes in Na(v)1.6-IR for nodes of Ranvier in myelinated dental axons.

On the local applications of antibiotics and antibiotic-based agents in endodontics and dental traumatology.

Antibiotics are a valuable adjunctive to the armamentarium available to health professionals for the management of bacterial infections. During endodontic treatment and when managing trauma to the teeth, antibiotics may be applied systemically (orally and/or parenterally) or locally (i.e. intra-dentally via irrigants and medicaments). Due to the potential risk of adverse effects following systemic application, and the ineffectiveness of systemic antibiotics in necrotic pulpless teeth and the periradicular tissues, the local application of antibiotics may be a more effective mode for delivery in endodontics. The aim of this article was to review the history, rationale and applications of antibiotic-containing irrigants and medicaments in endodontics and dental traumatology. The search was performed from 1981 to 2008 and was limited to English-language papers. The keywords searched on Medline were 'Antibiotics AND endodontics', 'Antibiotics AND root canal irrigation', 'Antibiotics AND intra-canal medicament', 'Antibiotics AND Dental trauma' and 'Antibiotics AND root resorption'. The reference section of each article was manually searched to find other suitable sources of information. It seems that local routes of antibiotic administration are a more effective mode than systemic applications. Various antibiotics have been tested in numerous studies and each has some advantages. Tetracyclines are a group of bacteriostatic antibiotics with antibacterial substantivity for up to 12 weeks. They are typically used in conjunction with corticosteroids and these combinations have anti-inflammatory, anti-bacterial and anti-resorptive properties, all of which help to reduce the periapical inflammatory reaction including clastic-cell mediated resorption. Tetracyclines have also been used as part of irrigating solutions but the substantivity is only for 4 weeks. Clindamycin and a combination of three antibiotics (metronidazole, ciprofloxacin and minocycline) have also been reported to be effective at reducing bacterial numbers in the root canal systems of infected teeth.

[Clinical properties of mineral trioxide aggregate].

Goal of the research was determination of effectiveness of clinical application of MTA. The study covered 79 molars of 79 patients (46 lower and 33 upper molars). The perforated areas were closed with MTA. Perforations were localized in various sections of crowns of teeth (over-junction--12, under-junction--23, in furcating area--44). The conclusion is that successful application of MTA requires attentive and careful approach, similar to any innovative technology in practical dentistry. In the article authors considered treatment of two-root incisors. Endo-treatment of perforation in the furcating area was conducted. In the other cases treatment was conducted on 16 teeth, in which the perforated areas were localized at the aperture of medial root. The third case shows closing of the resorbed apical hole in 46 teeth. In all clinical cases MTA was applied. The results of this study suggest that MTA would widen the capacities of dentists in their everyday work--in the process of treatment of teeth with various perforations.

Mineral trioxide aggregate as repair material for furcal perforation: case series.

The purpose of treating furcal perforation is to seal the artificial communication between the endodontic space and the periradicular tissue to prevent alveolar bone resorption and damage to the periodontal ligament. These complications are not infrequent in cases of furcal and/or old perforations, which show a worse prognosis than fresh, small, coronal, and apical perforations. Mineral trioxide aggregate (MTA) is widely used to seal perforations because of its biocompatibility and sealability. Ten cases of furcal perforation were selected at the department of Endodontics, University of Florence. All the perforations were cleaned with NaOCl, EDTA, and ultrasonic tips and sealed with MTA without internal matrix. Finally, the teeth were endodontically treated and coronally restored. Clinical and radiographic follow-ups were done at 6 months, 1 year, 2 years, and 5 years. After 5 years, the absence of periradicular radiolucent lesions, pain. and swelling along with functional tooth stability indicated a successful outcome of sealing perforations in 9 out of 10 teeth. One patient dropped out of the study after the 1-year follow-up and could not be contacted for further recalls. The results confirm that MTA without matrix provides an effective seal of root perforations and clinical healing of the surrounding periodontal tissue.

The ability of Portland cement, MTA, and MTA Bio to prevent through-and-through fluid movement in repaired furcal perforations.

This study assessed the ability of Portland cement, white Angelus-mineral trioxide aggregate (MTA), and MTA Bio to seal furcal perforations in extracted human molar teeth. Fifty-five human mandibular molar teeth were accessed, and the canal orifices were located. The roots were horizontally sectioned in the middle third. Resin composite was used to fill the root canal orifices and the apical end of the root. Perforations were created in the center of the pulp chamber floor by using a size 3 round bur. The teeth were divided into 3 groups (n = 15), and an additional 10 teeth served as controls. In G1, the perforation defects were repaired with MTA, whereas in G2 and G3, MTA Bio and Portland cement were used, respectively. Each tooth was assembled in a hermetic cell to allow the evaluation of fluid filtration. Leakage was measured by the movement of an air bubble traveling within a pipette connected to the teeth. Measurements of the air bubble movement were made after 10 minutes at a constant pressure of 20 cm H(2)O. Kruskal-Wallis H test was applied to the fluid flow data to detect differences between the experimental groups (P < .05). Leakage existed in every sample and was very variable in all the experimental groups, ranging from 0.098-0.51 microL/min. Kruskal-Wallis H-test results showed that there was no significant difference in mean fluid flow between the experimental groups (P = .874). The sealing ability promoted by the 3 cements was similar; no cement was able to produce a fluid-tight seal.

Ameloblastin fusion protein enhances pulpal healing and dentin formation in porcine teeth.

Ameloblastin (Ambn, also named "amelin" or "sheathlin") is a protein participating in enamel formation and mesenchymal-ectodermal interaction during early dentin formation in developing teeth. Experiments have demonstrated an association between Ambn expression and healing of acute pulp wounds. The purpose of this study was to investigate if local application of recombinant fusion Ambn (rAmbn) could influence reparative dentin formation in pulpotomized teeth. In this randomized, double-blinded study, pulpotomy was performed in 28 lower central incisors in 17 adult miniature pigs. Following the surgical procedure, the exposed pulp tissue was covered either with rAmbn or with calcium hydroxide. After 2, 4, or 8 weeks, the teeth were extracted and examined by histomorphometry and immunohistochemistry using antibodies against porcine ameloblastin, collagen type I, and dentin sialoprotein (DSP). In rAmbn-treated teeth, a substantial amount of newly formed reparative dentin was observed at the application site, completely bridging the pulpal wound. Dentin formation was also observed in calcium hydroxide-treated teeth; however, the amount of reparative dentin was significantly smaller (P < 0.001) than after rAmbn treatment. Immunohistochemistry confirmed that the new hard tissue formed was similar to dentin. This is the first time a direct link between ameloblastin and dentin formation has been made in vivo. The results suggest potential for rAmbn as a biologically active pulp-dressing agent for enhanced pulpal wound healing and reparative dentin formation after pulpotomy procedures.

Traumatic intrusion of permanent teeth. Part 3. A clinical study of the effect of treatment variables such as treatment delay, method of repositioning, type of splint, length of splinting and antibiotics on 140 teeth.

A prospective study of 140 intruded permanent teeth was examined for the following healing complications: pulp necrosis (PN), root resorption (RR; surface, inflammatory and replacement resorption), and defects in marginal periodontal bone healing (MA). The occurrence of these healing complications was related to various treatment factors such as treatment delay, method of repositioning (i.e. expecting re-eruption, orthodontic reposition and surgical reposition), type of splint (rigid, semirigid and flexible), length of splinting (days) and the use of antibiotics. Treatment delay, i.e. before and after 24 h, had no effect upon healing. Active repositioning in individuals with incomplete root formation (surgical or orthodontic) had a negative effect upon the three healing parameters compared with spontaneous eruption. In teeth with complete root formation and an age of 12-17 no repositioning was still the best treatment in regard to MA. In individuals older than 17 years of age, cases were not anticipated to spontaneously erupt and in these cases, the general choice of treatment was either active orthodontic or surgical repositioning. The former procedure appeared in this treatment scenario to slightly reduce the risk of MA complications. However, this treatment procedure was also found to be more time demanding (an average of 22 consultations for orthodontic repositioning compared with 17 consultations for surgical repositioning). If a surgical repositioning was performed, the type of splint (i.e. flexible, semirigid or rigid) appeared to have no significant effect on the type of healing. The same applied to the length of splinting time (shorter or longer than 6 weeks). No effect of dentin covering procedures for associated crown fractures (enamel-dentin fractures) could be demonstrated. Likewise, antibiotics had no apparent effect upon healing. In conclusion, in patients with intruded teeth with incomplete root formation, spontaneous eruption should be expected. In patients with completed root formation and with an age of 12-17 spontaneous eruption can still occur, but must be monitored very carefully. In older patients (i.e. >17 years) with completed root formation, either surgical or orthodontic extrusion should be attempted. The latter procedure appeared to lead to a slight reduction (not significant) in the risk of MA complications. The extent and direction of the intrusion may however favour surgical repositioning.

Preferential attachment of human gingival fibroblasts to the resin ionomer Geristore.

The resin ionomer Geristore has been used extensively for root perforation repairs. The purpose of this study was to evaluate oral in vitro biocompatibility of the resin ionomer Geristore compared to two other dental perforation repair materials, Ketac-Fil and Immediate Restorative Material (IRM). Growth and morphology of human gingival fibroblasts (HGFs) was determined using scanning electron microscopy (SEM) of HGFs cells grown on test materials as well as cytotoxicity assays using eluates from test materials. SEM analysis showed that HGFs attached and spread well over Geristore with relatively normal morphology. SEM showed that fibroblasts did not attach and spread well over Ketac-Fil or IRM as cells appeared much fewer with rounded and different morphology than fibroblasts grown on Geristore. Cytotoxicity assays indicated that HGFs proliferated in the presence of Geristore eluates and not in the presence of Ketac-Fil or IRM eluates. In vitro interpretation indicates that Geristore is less cytotoxic to gingival fibroblasts.