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As dental imaging accounts for approximately 40 % of all X-ray examinations in Germany, profound knowledge of this topic is essential not only for the dentist but also for the clinical radiologist. This review focuses on basic imaging findings regarding the teeth. Therefore, tooth structure, currently available imaging techniques and common findings in conserving dentistry including endodontology, periodontology, implantology and dental trauma are presented. Literature research on the current state of dental radiology was performed using Pubmed. Currently, the most frequent imaging techniques are the orthopantomogram (OPG) and single-tooth radiograph, as well as computer tomography (CT) and cone beam CT mainly for implantology (planning or postoperative control) or trauma indications. Especially early diagnosis and correct classification of a dental trauma, such as dental pulp involvement, prevents from treatment delays or worsening of therapy options and prognosis. Furthermore, teeth are commonly a hidden focus of infection.Since radiologists are frequently confronted with dental imaging, either concerning a particular question such as a trauma patient or regarding incidental findings throughout head and neck imaging, further training in this field is more than worthwhile to facilitate an early and sufficient dental treatment. · This review focuses on dental imaging techniques and the most important pathologies.. · Dental pathologies may not only be locally but also systemically relevant.. · Reporting of dental findings is important for best patient care..· Masthoff M, Gerwing M, Masthoff M et al. Dental Imaging - A basic guide for the radiologist. Fortschr Röntgenstr 2019; 191: 192 - 198. Da die dentale Bildgebung etwa 40 % aller Röntgenuntersuchungen in Deutschland ausmacht, sind fundierte Kenntnisse für den klinischen Radiologen auf diesem Gebiet essenziell. Der Fokus dieser Übersichtsarbeit liegt auf der Bildgebung des Zahnes. Hierfür werden Zahnaufbau, derzeit verfügbare Bildgebungstechniken und häufige Befunde der konservierenden Zahnheilkunde einschließlich der Endodontologie, Parodontologie und der Implantologie sowie nach dentalem Trauma vorgestellt. Es erfolgte eine Literaturrecherche zur dentalen Radiologie mittels Pubmed. Bildgebungstechniken erster Wahl sind weiterhin das Orthopantomogramm (OPG) sowie die Einzelzahnaufnahme. Ergänzend werden die Computertomografie (CT) und die digitale Volumentomografie (DVT), vorrangig für die Implantologie (Behandlungsplanung und Verlaufskontrolle) oder verunfallte Patienten, eingesetzt. Insbesondere beim dentalen Trauma vermeidet eine exakte Diagnostik und korrekte Klassifikation, beispielsweise bezüglich einer Beteiligung der Zahnpulpa, Therapieverzögerungen oder deren Prognoseverschlechterung. Zudem können Zähne einen häufigen Infekt-Fokus darstellen.Da Radiologen häufig mit der dentalen Bildgebung konfrontiert werden, sei es als dezidierte Fragestellung bei einem Trauma-Patienten oder bei Zufallsbefunden im Rahmen der Kopf-/ Halsbildgebung, ist eine „Blickschulung“ für häufige Befunde lohnenswert, um frühzeitig eine suffiziente zahnärztliche Behandlung zu bahnen. · Dieser Review behandelt die dentalen Bildgebungstechniken sowie die wichtigsten Zahnpathologien.. · Zahnpathologien können nicht nur lokal, sondern auch systemisch relevant sein.. · Dentale Befunde sollten für eine bestmögliche Patientenversorgung Teil der Befundung sein..· Masthoff M, Gerwing M, Masthoff M et al. Dental Imaging - A basic guide for the radiologist. Fortschr Röntgenstr 2019; 191: 192 – 198.

In the context of tooth trauma, mostly the maxillary central front teeth are involved, whereby their roots are in some cases still in the developing stage (immature). Depending on the type of trauma, a necrosis of the pulp is the consequence or at least foreseeable. In order to preserve such a tooth, an endodontic therapy is inevitable. The disadvantage of conventional endodontic therapy methods of immature teeth (apexification, apexogenesis) is the root growth stop. Alternatively, the regeneration/revascularisation of the dental pulp (RP) was suggested, that allows a further root growth. The aim of this case report is to present the procedure of a RP-therapy and to suggest a step-by-step manual.

The purpose of the present retrospective study was to evaluate the post-traumatic healing of the pulp and periodontium of 32 permanent teeth with horizontal root fractures. Twenty-nine patients, 8-48 years old, who presented at our department with a root fracture between January 2001 and April 2007, participated in the study. Root-fractured teeth with a loosened or dislocated coronal fragment were repositioned and splinted for 14-49 days (average: 34 days). In cases of severe dislocation of the coronal fragment, prophylactic endodontic treatment was performed. Follow-up examinations were conducted routinely after 1,2,3,6, and 12 months. For this study, follow-up took place for up to 7 years post trauma. Of 32 root-fractured teeth, 29 (91%) survived. 10 teeth (31%) exhibited pulpal healing; 13 teeth (41%) were prophylactically endodontically treated within 2 weeks of injury. At the fracture line, interposition of calcified tissue was evident in 6 teeth (19%), and interposition of granulation tissue was observed in 8 teeth (25%). The prognosis of the root-fractured teeth was good, and one-third of the teeth with root fractures possessed a vital pulp at the final examination.

The increase of international movements has led to a greater demand for forensic age estimation of foreigners without valid identification documents. Age estimation on living individuals is part of asylum and criminal proceedings. Age estimation has become also important within identification of victims, because of the fact of increasing natural disasters and events of terrorism. Therefore dentists are more and more appointed to this job. There are varieties of methods in age estimation. Dental examination and analysis of panoramic x-ray are usually used for dental age estimation.

Malignant melanoma of the oral cavity is a rare disease with high lethality, rapid progression and frequently seen lymph node metastases. The clinical appearance of the mucosal melanoma is mostly irregular in shape and dark blue, brown or black in colour. During early stages the lesions are painless with a tendency to spontaneous bleeding. Mucosal melanoma shows expansive and infiltrative growth into neighbouring structures, with the result of bone destruction and loss of teeth. We present a case of a female patient with a primary mucosal melanoma. A local infiltration and invasion of a tooth could be seen. Although many publications deal with oral mucosal melanoma with local destruction of bone, there are no reports on an infiltration into dental roots. Aspects of this unusual infiltration of hard tissues are discussed.

This review article arranges the current results of stem cell biology for their use in dentistry. There are different types of stem cells, which are applicable for dental treatments. The use of embryonic stem cells, whose possibilities for breeding an artificial tooth were hardly evaluated, is however ethically precarious. On the other side the ethically harmless adult stem cells, which were isolated for example from bone marrow, were little examined for their capability of differentiation into dental tissues. Therefore their forthcoming use in dentistry is rather improbable. However, dental ectomesenchymal stem cells are more promising for dentistry in future. For example dental pulp stem cells (DPSCs) are capable to differentiate into dentin under in vitro conditions. Moreover it is possible to use periodontal ligament (PDL) stem cells and dental follicle precursors for periodontal tissue differentiations in vitro. Recently new populations of stem cells were isolated from the dental pulp and the PDL. These cells distinguish from the initially isolated DPSCs and PDL stem cells in growth and cell differentiation. Therefore stem cell markers are very important for the characterization of dental stem cells. A significant marker for dental stem cells is STRO-1, which is also a marker for bone marrow derived mesenchymal stem cells. Nonetheless dental stem cells are CD45 negative and they express rarely hematopoietic stem cell markers. These research results plead for the participation of dental stem cells in dental practice in future.

The study evaluated the cytotoxicity of five self-etching dentin adhesive systems applied on dentin specimens of different thicknesses. The test materials (A: Adper Prompt-L-Pop, B: Xeno II, C: Clearfil SE Bond, D: One up Bond F, E: Resulcin Aqua PrimeMonobond) and a positive control (35% H202) were applied on 1.0, 1.5 and 2.5 mm thick bovine dentin specimens (each subgroup n = 5) in a dentin barrier test device. The experiments were performed with perfusion (2 ml/h) of the pulpal part of the chamber. The eluates were obtained before (baseline) and 15, 30, 45, 60 and 120 min after application of the adhesives and pipetted onto L-929 fibroblasts. Cytotoxicity of the materials was determined in relation to the baseline value using the MTT assay and statistical analysis was performed by ANOVA. After 15 min perfusion, test materials B-E applied on 1.0 mm and B and E applied on 1.5 mm dentin specimens exhibited cytotoxic potential. However, after 30 min perfusion none of the adhesives showed any toxicity. Cytotoxicity decreased with increasing thickness of the dentin slices and was lower for Adper Prompt-L-Pop compared to adhesives B-E. Self-etching adhesive systems might exhibit cytotoxic potential when applied on dentin of less than 1.5 mm thickness. However, cytotoxicity of the materials decreased with increasing dentin thickness and increasing duration of perfusion.

Pulp sensitivity and vitality changes were evaluated in 69 traumatized maxillary incisors and in 38 control teeth during a follow-up period of 20 months. Examinations included thermal testing using carbon dioxide snow (CO2) and the laser Doppler flowmetry (LDF). These measurements were compared to the clinical and radiological findings. In 47.8% of the traumatized teeth and in 55.3% of the control group the three LDF measurements corresponded with the sensitivity testing using CO2 and with the clinical and radiological findings. In 31.9% of the traumatized teeth and in 7.9% of the control group the LDF-measurements differed from the CO2-measurements, but were in agreement with the other clinical and radiographic findings. The information obtained by laser Doppler flowmetry is of additional importance for the treatment planning. Since the clinical examination of traumatized teeth is sometimes inconclusive, the laser Doppler flowmetry is a further diagnostic tool but it cannot replace the radiological or clinical examination.

Diseases of the mandible affect the soft tissues aside from the osseous manifestation. This can be shown clearly and in great detail by magnetic resonance imaging (MRI). MRI is the gold standard in the diagnostic evaluation of any internal derangement of the temporomandibular joint. Dental MRI requires high resolution techniques and in some cases also intravenous administration of contrast material. These techniques allow delineation of the neurovascular bundle. In the past few years new indications were formulated, for example, the evaluation of the integrity of the inferior alveolar nerve in trauma and in radicular cysts. New quantitative methods now enable insights into the pathophysiology. The objective of this review is to communicate accepted indications for MRI of the mandible and to present innovative applications.

The aim of the present study was to investigate whether body acupuncture is suitable to increase the pre-pain sensitivity threshold (PPST).For this purpose, the PPST was algesimetrically determined after pulpal electric stimulation (baseline) in 24 patients with healthy frontal teeth.After acupuncture at specific (test group) and unspecific sites (control group, placebo acupuncture), the shift of the PPST was registered. After stimulation of specific acupuncture sites, a mean increase of 110% of the PPST could be obtained. Stimulation at unspecific sites showed only an increase of the PPST of 30%. To which extent this pain reduction is due to a physiological effect on pain reception, or physical irritation, or suggestion could not be verified in this study. Also, the endorphin theory discussed in connection with acupuncture could neither be proved nor disproved. Further controlled clinical studies have to be carried out to prove under clinical conditions the positive results of this experimental algesimetric study.

The purpose of the present investigation was to measure the effect of tooth intrusion and extrusion on pulpal blood flow in man. The flow changes were measured in 10 lateral incisors (6 subjects) by means of laser Doppler flowmetry (Perimed, Sweden) applied on the buccal surface through metal tubes bonded to the teeth. Brackets were bonded onto teeth 13 and 23, and intrusive and extrusive forces of 2 N were applied in random order to the experimental tooth for 5 min before unloading. The contralateral tooth served as a control. Extrusion of the teeth gave no significant changes in pulpal blood flow during loading or unloading. However, intrusion of the teeth reduced the pulpal blood flow by 20% during the first minute after force application. The pulpal blood flow gradually increased towards the preloading flow values for the next 4 min, and was returned to the prestimulus level 3 min after unloading. In conclusion orthodontic intrusion of teeth with a 2 N force evoked a temporary reduction in the pulpal blood flow, whereas extrusion had no effect on the pulpal blood flow.

21 autotransplanted teeth were examined by using laser Doppler flowmetry (LDF) at 1, 2, 3, 6 and 12 postoperative weeks. 20 teeth showed statistically significantly higher perfusion units up to the 6th weeks as compared to the control group. At 12 postoperative weeks, the perfusion values of the autotransplanted teeth were at the same level as those of the control group. It was possible to show a non-revascularisation of one tooth with LDF. Currently, LDF can be considered as the only practicable, non-invasive method to evaluate the revascularization of autotransplanted teeth.

This in-vitro study reports on a modified method for testing shear bond strength of dentin bonding agents (DBA's). For a better imitation of the surface of vital human dentin, all DBA's used in this investigation (12 commercially available and one experimental) were tested with dentin under intrapulpal pressure (19.6 cm/36 cm H2O) and exposed to thermal cycling (x1500, 5 degrees C/55 degrees C). In group A the bonding agent was light cured before the application of the composite resin. In group B the bonding agent and the composite resin were light cured at the same time. The difference between the modified testing method and a commonly used method (application of the DBA onto a dry dentinal surface, water storage at 37 degrees C for 24 h) was significant (p0.001, ANOVA two way). The shear bond strengths recorded with our method were generally lower than formerly published results. A.R.T. Bond and Experimental had the best average results in both testing groups. Superbond CB bond strength had to be interpreted separately.

The blood vascular supply of the dental pulp of 15 domestic sheep of varying age and sex was investigated using light and electron microscopy. The pulp vascular system is showing arterioles with a media of varying thickness and with endothelial cells of variable structure. In the transitional zone between crown and root pulp, the arterioles are taking a typical S- or U-shaped course. The capillary network of the crown pulp is denser and more regular than that in the root pulp. In addition to the capillaries lined by a continuous endothelial tube, there may be others with a typically fenestrated endothelial lining. Specialised vascular structures of the peripheral blood vessels, especially arterio-venous anastomoses as described in man, have not been observed in the sheep.

In order to investigate odontoblasts and predentin surfaces using SEM techniques, teeth of sheep with one or several roots were subjected to critical point drying. The odontoblasts of the root pulp are distinguished in their shape and arrangement pattern from those in the crown pulp. They regularly are detaching only one process of Tomes, which is extending up to the border between dentin and enamel and which shows a dendritic ramification in the dentin next to the enamel. The distal cell portions of the odontoblasts are joined together by a system of terminal bars. The collagen structures observed between the odontoblasts and predentin are considered to be von Korff's fibres as found in man.

The aim of the present in-vitro study was to evaluate the changes in pulp temperature associated with thermal debonding of ceramic brackets using the Ceramic Debonding Unit (Dentaurum). In addition, several forms of false usage were simulated. Instead of thermoelements, the non-contact infrared thermography device SST/THETA 1000 (Heimann) was employed for the dynamic measurement of pulp temperature. Successful debonding after a single activation resulted in a maximal temperature change of 3 degrees C. These in vitro results indicate that the Ceramic Debonding Unit--properly applied--is gentle on the pulp tissue. If debonding fails, the increase in temperature is higher. The influence of differing bracket base morphologies and various resins on electrothermal debonding are discussed.

The authors studied the dental pulp morphology and distribution of acid and neutral mucopolysaccharides in teeth subjected to orthodontic therapy. The teeth were moved with a fixed appliance using forces of 60-200 g. Changes in the histological structure of the dental pulp followed the therapy. The number of collagen fibres increased; they were densely packed and formed thick bundles. A certain degree of hyalinization was also observed. The dental pulp cavity was narrowed by apposition of hard tissue deposits along the canal wall. Pulp stones and diffuse calcification were often encountered. The reaction of acid mucopolysaccharides was found to be very weak, sometimes even negative. The reaction of neutral mucopolysaccharides was not affected so markedly. The results of the paper suggest that changes induced in the dental pulp with fixed orthodontic appliances are irreversible and correspond to those of aging. These premature changes together with rapid hard tissue formation, may negatively influence endodontic treatment in the future.

Undecalcified sections of 31 impacted third molars are examined histologically for signs of resorption. Resorption starts at small spots in enamel, progresses to dentin and may even penetrate the pulp cavity. The incidence of such resorption processes increases after the age fifty. A prerequisite for resorption is the loss of reduced ameloblastic epithelium. Histological examination reveals multinuclear giant cells and apposition of spongious bone to destroyed dental substances. The results is dental ankylosis. Because partially resorbed teeth or ankylosed teeth may lead to serious surgical difficulties, impacted wisdom teeth without any clinical symptoms and without pathologic radiological findings should always be extracted at a young age.

The nerve supply of the pulp was investigated in 17 sheep of various breeds and age groups belonging to both sexes, using light and electron microscopy. The following results were obtained: The dental pulp of sheep is supplied with myelinated and unmyelinated nerve fibres. The subodontoblastic plexus of Raschkow, as found in man, is absent in sheep. Single axons may be found in the predentine between the odontoblasts and near Tomes' processes. The rare occurrence of both subodontoblastic nerve fibres and cells of the immune system in the ovine pulp is discussed in relation to evolutionary processes, in light of the fact that sheep are relatively resistant to caries.

The fine tissue structure of ovine odontoblasts was studied in various developmental and maturational stages. Odontoblasts differentiate from the peripherally-located mesenchymal cells of the dental papilla. On the basis of cytological parameters, it was possible to divide the odontoblasts into the following groups: pre-odontoblasts, juvenile (light) odontoblasts and mature (dark) odontoblasts. The three maturational stages of odontoblasts exhibit substantial differences with respect to their form and to the number and arrangement of their cytoplasmatic organelles. Structural differences in the three cell types appear to be closely correlated to the level of cellular activity.

The mechanical debonding of ceramic brackets using special instruments involves the use of a degree of force that is damaging to the enamel. For this reason, the authors have developed the Ceramic Debonding Unit for the thermal debonding of ceramic brackets. The unit reduces the force necessary for debonding, without overheating the tooth. The present article explains the principle of the unit. The influence on the temperature increase in the pulpa of the mechanical torque applied during debonding, and the time taken for debonding was investigated in extracted teeth (lower central incisors). Tests on ceramic brackets made by various manufacturers showed that safe debonding is possible if the debonding time does not exceed 3 seconds at a torque of 100 Nnm. The temperature increase in the pulpa will not exceed 5 degrees C when the Ceramic Debonding Unit is used under these conditions, so that harmful overheating of healthy teeth does not occur.

Electrical resistance measurements may be used to determine the situation of the pulp horn tips of teeth prepared for crown restorations. The resistance value recorded for these sites of minimum dentin thickness depends on the thickness of the dentin layer and the degree of tooth development. A resistance value of 25 k omega revealed dentin thickness of 0.7-1.45 mm. The teeth of younger patients had thicker dentin layers than those of older patients.

The pulpal response of the glass ionomer cement Ketac fil was investigated in a biological usage test in human and pig teeth. The mainly no or slight pulpal response in all test periods leads to the conclusion that Ketac fil in deep cavities with calcium hydroxide is not necessary.

Compared with a step-by-step procedure, the one-step excavation of deep carious lesions in primary molars proved to be the treatment of choice in a clinically, microbiologically and histologically controlled trial. The stepwise method failed to produce any significant reduction in pulp exposure. Sensitivity assessment and percussion findings did not result in a reliable and unambiguous evaluation of treatment success. Histology showed inflammation-free pulps in 67% of the deciduous molars irrespective of the treatment method used. Microbiological examination revealed slightly softened dentin to be significantly more infected than clinically acceptable, hard dentin; although only 59.3% of the cavity floors were free of microorganisms. Chronic pulp inflammations were correlated with the presence of streptococci and lactobacilli, whereas actinomycetes were associated with inflammation-free pulps.

The Er:YAG Laser is an effective tool for removing hard tooth structure without causing any measurable degree of thermal damage. In view of the fact that the process of ablation basically depends on thermal effects, pulpal microcirculation was studied by Laser-Doppler flowmetry during Er:YAG Laser irradiation. Rat incisors were used to demonstrate that pulp damage can be avoided if correct laser parameters are used for preparing enamel and dentin.

An electronic pulp tester was used to study the stimulus threshold in human teeth of 28 healthy volunteers for 1,5-4 days and the duration of local anaesthesia in 55 patients with caries. Rhythm analysis was performed with a non-linear fitting program on an IBM computer (PHARMFIT); in 21 out of the 28 volunteers significant daily rhythms in stimulus threshold could be detected. In the patients the maximum duration of local anaesthesia was after drug application at 2 p.m.

The direct and indirect effect on the endodont after thermic treatment with the micro-plasma unit from EGIDE were examined in animal experiments. The EGIDE unit is considered by its producer to be an alternative for CO2 lasers. The histological evaluation showed that both the plasma-therapy of dentin and the exposed pulp lead to massive pathological changes of endodont and was inferior to traditional methods as the indirect pulpcapping.

The effect on the pulp-dentin system by chlorhexidine 0.2% in comparison to the physiological sodium chloride solution was investigated in animal experiments. The methods of tests were based on the requirements of FDI 1980. After 3, 21, 70 and 90 days the teeth were extracted and prepared for histological studies. The evaluation of the histological preparations including measurement on the residual dentin layer was achieved by light microscopy. Differences in the pulp reaction after treatment of the teeth with chlorhexidine or sodium chloride solution could not be observed. The changes of pulp tissue were slight to moderate and depended on the residual dentin layer. The cavity cleaning with chlorhexidine 0.2% did not cause any additional damage in the pulp.

The authors studied distribution of alkaline and acid phosphatases, non specific esterase and NADH2 tetrazolium reductase in the dental pulp of children treated by fix orthodontic appliances. All the enzymes studied exhibited positive reaction, the activity, however, was lower than in the controls, except of the alkaline phosphatase. The results of the study demonstrated that the forces between 60-200 g cannot be evaluated as biologically favorable.

This article presents a animal study on 36 teeth by dogs without definite race. By the histological observation we cannot assess a damage of the pulp by application of CuRAY-FIL with a basic material. The clinical and REM observations after 11 and 24 months by 76 patients pointed out: CuRAY-FIL has a good colour stability and adhesion, however the claims on a optimal filling material for the restoration in the visible area are not accomplished in all points.