6 Abstract The development of the mouse tooth primordium is an important model for studying odontogenesis, as well as general organogenesis. The development of the mouse lower incisor is of remarkable interest. The epithelial anlage of the mouse lower incisor is interconnected with the vestibular anlage via the epithelial bridges. According to some authors, the epithelial bridges represent an area, where the transient rudimentary incisor germ appears. From a morphological point of view, the first sign of ongoing epithelial-mesenchymal interactions during early odontogenesis is the thickening of oral epithelium. From a molecular point of view, it is the expression of the Shh, Eda, Edar, Pitx2, Bmp2, Bmp4 and Dlx2 genes. Except for the transcription domain, representing the proper signalling centre of a developing prospective incisor, a transient transcription domain, localized anteriorly and superficially, appears in the odontogenic zone of the epithelium during early development. The anterior transcription domain originates in the area of epithelial bridges, and according to some authors, from an evolutionary point of view, it corresponds with the signalling centre of the rudimentary incisor germ. The aim of this diploma thesis was to compare the temporospatial dynamics of SHH and EDA protein expression in...

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20561号 / 医博第4246号 / 新制||医||1022(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 松田 秀一, 教授 瀬原 淳子, 教授 妻木 範行 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Thesis (M.Dent.), Faculty of Health Sciences, University of the Witwatersrand, 2009 / This in vitro study compares tooth bleaching and consequences of tooth surface effects of Ozicure Oxygen Activator (O3, RSA) with Opalescence Quick (Ultradent, USA) tooth bleaching. One hundred and thirty six teeth (canines, incisors and premolars), which were caries free, had no surface defects and within the colour range 1M2 and 5M3. Teeth were randomly divided into the three experimental groups: Opalescence Quick, Ozicure Oxygen Activator and control. The three experimental groups received three treatments of one hour each over three consecutive days. Tooth colour was assessed using the VITAPAN 3D MASTER TOOTH GUIDE (VITA, Germany) and VITA Easyshade (VITA, Germany). A randomized block design was used to assess tooth colour change. A General Linear Models test for analysis of variance for a fractional design with significance set at P<0.05 was used. Both bleaching methods significantly lightened the teeth, visually (P<0.0001) and digitally (P= 0.013). Tooth colour change was seen after the first hour of tooth bleaching; thereafter there was little or no benefit. The tooth type played a significant role in tooth colour change (visually P=0.0416 and digitally P=0.004). The quality of the spectrophotometer may account for the different results found compared to the tooth guide. Scanning electron microscopy showed no effect of enamel loss following bleaching. Atomic force microscopy showed a 2.5 rougher enamel surface with Opalescence Quick.

The developing mouse dentition is a very useful tool to study molecular regulation of odontogenesis and also organogenesis. The embryonic mouse dentition comprises developing functional tooth primordia as well as rudimentary tooth primordia. These rudiments arrest their growth during development and either degenerate or become a part of a functional tooth. Mice with gene defects also allow elucidation of a function of genes, their products and signalling pathways. The protein ectodysplasin is essential for development of ectodermal derivatives - skin, hair, glands and teeth. The Tabby mice have a mutation in the Eda gene, which encodes the protein ectodysplasin, and they display a number of dentition anomalies. Early development of the lower jaw dentition in Tabby embryos has been already morphologically described. As a prerequisite for understanding regulatory mechanisms of odontogenesis in Tabby mice, it is also necessary to map the spatiotemporal dynamics of signalling centres that express Shh in both the rudimentary and functional tooth primordia. The aim of this thesis was to compare the signalling centres based on the Shh expression and its spatiotemporal dynamics in the lower jaw of Tabby and WT mouse embryos. Then the Shh data were correlated with known morphological data to clarify the...

A erosão dentária ocasiona a perda da estrutura dental através da dissolução da sua porção mineralizada por ácidos de origem não bacteriana. Assim, o objetivo deste estudo é avaliar a capacidade de materiais contendo compostos bioativos de remineralizar o esmalte bovino submetido a desafio erosivo e se o método de quantificação da fluorescência induzida por luz (QLF) tem correlação com os resultados do teste de microdureza Knoop. 120 fragmentos de esmalte bovino foram distribuídos entre os grupos experimentais, sendo n=5 para o teste de microdureza (3 x 3 x 2 mm) e n=10 para o método do QLFTM (5 x 5 x 3 mm). Os corpos-de-prova foram analisados em três momentos diferentes (inicial, após 2 dias de protocolo de erosão e após 6 dias de tratamento remineralizador). As amostras foram submetidas a 2 dias de protocolo de erosão, através de imersão em ácido cítrico a 0,3% pH 3,2, por 2 minutos e manutenção das mesmas em saliva artificial (pH 7,0) durante 24 horas. Na sequência, foram realizados os tratamentos remineralizadores por 6 dias consecutivos: 1 gota de saliva foi depositada sobre as amostras e após 1 hora foram imersas por 2 minutos em suspensão aquosa preparada com os seguintes materiais: G1-Pro-Argin+NaMFP, bicarbonato de arginina + carbonato de cálcio + monofluorfosfato de sódio (Colgate® Sensitive Pró-Alívio); G2-Recaldent+NaF, fosfopeptídeo de caseína com fosfato de cálcio amorfo + fluoreto de sódio (MI Paste Plus); G3-ACP+NaF, fosfato de cálcio amorfo + fluoreto de sódio + nitrato de potássio (Relief ACP); G4-CaGP+KF, glicerofosfato de cálcio + fluoreto de potássio (Flúor Protector Gel); G5-NovaMin®+NaF, fosfosilicato de cálcio e sódio + fluoreto de sódio (Nupro® Sensodyne®); G6-NovaMin®+NaMFP, fosfosilicato de cálcio e sódio + monofluorfosfato de sódio (Sensodyne® Repair&Protect); G7-NaF, fluoreto de sódio + nitrato de potássio (Sensodyne® Cool Gel) e G8-saliva artificial (controle negativo). Após 2 horas de imersão em saliva foi repetido o protocolo de erosão. Foram realizadas análises estatísticas para o teste de microdureza e QLF (=0,05). A ANOVA de dois fatores para medidas repetidas mostrou diferenças estatisticamente significativas apenas para os momentos da análise e para a interação dos fatores tratamentos x momentos da análise. O teste de Tukey mostrou diferenças significativas na comparação entre todos os momentos da análise e na interação momentos da análise x tratamentos: valores iniciais x após erosão e após tratamento e entre os valores após erosão x após tratamento (NovaMin®+NaF, NovaMin®+NaMFP, NaF e saliva). O teste de Tukey na comparação dos tratamentos no momento final da análise mostrou diferenças significativas na análise da microdureza para o Recaldent+NaF x NovaMin®+NaF, NovaMin®+NaMFP e NaF; mas no QLF, as diferenças ocorreram entre o Pro-Argin+NaMFP x NaF e saliva; Recaldent+NaF x NovaMin®+NaMFP, NaF e saliva e ACP+NaF x NaF. Nenhum dos tratamentos foi capaz de remineralizar totalmente o esmalte dental, mas os materiais Pro-Argin+NaMFP, Recaldent+NaF, ACP+NaF e CaGP+KF foram capazes de estabilizar o processo de erosão do esmalte com resultado superior aos demais tratamentos. O método do QLF mostrou uma correlação positiva significativa com os resultados do teste de microdureza. / Dental erosion leads to loss of the tooth structure by dissolving its mineral portion by acids for non-bacterial origin. The objective of this study is evaluate the ability of materials with bioactive compounds to remineralize bovine enamel subjected to erosive challenge and verify the possible correlation between the datas from the quantitative light-induced fluorescence method (QLF) and the Knoop surface microhardness test. 120 bovine enamel pieces were distributed among experimental groups with n=5 for microhardness testing (3 x 3 x 2 mm) and n=10 for the QLF method (5 x 5 x 3 mm) and were analysed at three different times (initial, after 2 days of erosion protocol and after 6 remineralizing days of treatment).The samples were subjected to two-days erosion protocol, through its immersion into 0,3% citric acid solution pH 3,2 for 2 minutes and maintaining them into artificial saliva for 24 hours (pH 7,0). Following remineralizing treatments were performed for 6 consecutive days: the samples were covered with 1 drop of saliva and after 1 hour were immersed for 2 minutes in the slurry prepared with the following materials: G1-Pro-Argin+NaMFP, arginine bicarbonate + calcium carbonate + sodium monofluorophosphate (Colgate® Sensitive Pro-Alívio); G2-Recaldent+NaF, casein phosphopeptide-amorphous calcium phosphate + sodium fluoride (MI Paste Plus); G3-ACP+NaF, amorphous calcium phosphate + sodium fluoride + potassium nitrate (Relief ACP); G4-CaGP+KF, calcium glycerophosphate + potassium fluoride (Fluor Protector Gel); G5- NovaMin®+NaF, calcium sodium phosphosilicate + sodium fluoride (Nupro® Sensodyne®); G6-NovaMin®+NaMFP, calcium sodium phosphosilicate + sodium monofluorophosphate (Sensodyne® Repair&Protect); G7-NaF, sodium fluoride + potassium nitrate (Sensodyne® Cool Gel) and G8-Artificial saliva (negative control). After 2 hours of soaking in saliva the erosion protocol was repeated. Statistical analyzes were conducted for microhardness and QLF with coincidence of the results (=0,05). A two-factors ANOVA for repeated measures showed statistically significant differences only for the time of analysis and the interaction treatments x time of analysis. The Tukey test showed statistically significant differences when comparing the three times of analysis and the interaction between times of analysis x treatments: baseline values with values after erosion and after treatment and the values after erosion x after treatment (NovaMin®+NaF, NovaMin®+NaMFP, NaF and saliva). The Tukey test when comparing the treatments x final times of analysis showed statistically significant differences in microhardness test for Recaldent+NaF x NovaMin®+NaF, NovaMin®+NaMFP and NaF; in QLF method the differences occurs between Pro-Argin+NaMFP x NaF and saliva; Recaldent+NaF x NovaMin®+NaMFP, NaF and saliva; ACP+NaF x NaF. None of the treatments was able to completely remineralize bovine enamel, but Pro-Argin+NaMFP, Recaldent+NaF, ACP+NaF and CaGP+KF materials were able to stabilize the eroding enamel, thus demonstrating a score higher than others and the QLF method showed a significant and positive correlation with the microhardness test results.

Para avaliação da resistência à fratura de dentes caninos de cães restaurados biologicamente (colagem de fragmento) foram utilizados 50 dentes distribuídos em cinco grupos de dez dentes cada. Com exceção dos dentes do grupo 1, que serviram de controle, os demais foram seccionados e posteriormente restaurados com o próprio fragmento (colagem) através de diferentes protocolos: Grupo 2: pino fundido (Níquel-Cromo) e cimento resinoso; Grupo 3: pino de fibra de vidro e cimento resinoso; Grupo 4: pino de fibra de carbono e cimento resinoso; Grupo 5: não foram utilizados pinos, apenas adesivo e resina composta fotopolimerizável (colagem simples). Os dentes foram, então, submetidos a teste de resistência através da aplicação de uma carga perpendicular ao longo eixo do dente na sua face lingual. Os resultados permitiram concluir que a utilização de pinos intra-radiculares teve influência significativa na resistência à fratura dos dentes colados quando comparada ao grupo de colagem simples, no entanto, foi de 45,4 %, 14,2%, 11,4% (respectivamente para os grupos 2, 3 e 4) da resistência necessária para fraturar os dentes íntegros, enquanto para o grupo 5 foi de 7,0 %. Dessa forma, nas condições deste experimento, os protocolos nos quais se utilizam pinos intra-radiculares parecem ser os mais indicados para colagem de dentes caninos fraturados. / To determine the fracture strength of canine teeth of dogs restored biologically (bondind of tooth fragment), 50 teeth were used and distributed in 5 groups of ten teeth each. The group 1 was the control (intact teeth). In the other groups the teeth were sectioned and bonded under different protocols: Group 2: cast post (Nickel-chromium) and resin luting cement; Group 3: Fiberglass post and resin luting cement; Group 4: Carbon fiber post and resin luting cement; Group 5: no post was used, only dentin adhesive and light-cured composite resin (simple bonding). The teeth were submitted to fracture strength test through the application of a perpendicular load to the tooth long axis in its lingual face. The results showed that the use of post improved significant fracture strength of bonding teeth when compared to the group of simple bonding, however this was 45.4%, 14.2%, 11.4% (respectively for the groups 2, 3 and 4) of the load necessary to fracture the sound teeth, whereas was it 7.0% in group 5. In these experimental conditions, the protocols where posts are used seem to be more indicated to bonding tooth fragment in fractured canine tooth.

A erosão dentária ocasiona a perda da estrutura dental através da dissolução da sua porção mineralizada por ácidos de origem não bacteriana. Assim, o objetivo deste estudo é avaliar a capacidade de materiais contendo compostos bioativos de remineralizar o esmalte bovino submetido a desafio erosivo e se o método de quantificação da fluorescência induzida por luz (QLF) tem correlação com os resultados do teste de microdureza Knoop. 120 fragmentos de esmalte bovino foram distribuídos entre os grupos experimentais, sendo n=5 para o teste de microdureza (3 x 3 x 2 mm) e n=10 para o método do QLFTM (5 x 5 x 3 mm). Os corpos-de-prova foram analisados em três momentos diferentes (inicial, após 2 dias de protocolo de erosão e após 6 dias de tratamento remineralizador). As amostras foram submetidas a 2 dias de protocolo de erosão, através de imersão em ácido cítrico a 0,3% pH 3,2, por 2 minutos e manutenção das mesmas em saliva artificial (pH 7,0) durante 24 horas. Na sequência, foram realizados os tratamentos remineralizadores por 6 dias consecutivos: 1 gota de saliva foi depositada sobre as amostras e após 1 hora foram imersas por 2 minutos em suspensão aquosa preparada com os seguintes materiais: G1-Pro-Argin+NaMFP, bicarbonato de arginina + carbonato de cálcio + monofluorfosfato de sódio (Colgate® Sensitive Pró-Alívio); G2-Recaldent+NaF, fosfopeptídeo de caseína com fosfato de cálcio amorfo + fluoreto de sódio (MI Paste Plus); G3-ACP+NaF, fosfato de cálcio amorfo + fluoreto de sódio + nitrato de potássio (Relief ACP); G4-CaGP+KF, glicerofosfato de cálcio + fluoreto de potássio (Flúor Protector Gel); G5-NovaMin®+NaF, fosfosilicato de cálcio e sódio + fluoreto de sódio (Nupro® Sensodyne®); G6-NovaMin®+NaMFP, fosfosilicato de cálcio e sódio + monofluorfosfato de sódio (Sensodyne® Repair&Protect); G7-NaF, fluoreto de sódio + nitrato de potássio (Sensodyne® Cool Gel) e G8-saliva artificial (controle negativo). Após 2 horas de imersão em saliva foi repetido o protocolo de erosão. Foram realizadas análises estatísticas para o teste de microdureza e QLF (=0,05). A ANOVA de dois fatores para medidas repetidas mostrou diferenças estatisticamente significativas apenas para os momentos da análise e para a interação dos fatores tratamentos x momentos da análise. O teste de Tukey mostrou diferenças significativas na comparação entre todos os momentos da análise e na interação momentos da análise x tratamentos: valores iniciais x após erosão e após tratamento e entre os valores após erosão x após tratamento (NovaMin®+NaF, NovaMin®+NaMFP, NaF e saliva). O teste de Tukey na comparação dos tratamentos no momento final da análise mostrou diferenças significativas na análise da microdureza para o Recaldent+NaF x NovaMin®+NaF, NovaMin®+NaMFP e NaF; mas no QLF, as diferenças ocorreram entre o Pro-Argin+NaMFP x NaF e saliva; Recaldent+NaF x NovaMin®+NaMFP, NaF e saliva e ACP+NaF x NaF. Nenhum dos tratamentos foi capaz de remineralizar totalmente o esmalte dental, mas os materiais Pro-Argin+NaMFP, Recaldent+NaF, ACP+NaF e CaGP+KF foram capazes de estabilizar o processo de erosão do esmalte com resultado superior aos demais tratamentos. O método do QLF mostrou uma correlação positiva significativa com os resultados do teste de microdureza. / Dental erosion leads to loss of the tooth structure by dissolving its mineral portion by acids for non-bacterial origin. The objective of this study is evaluate the ability of materials with bioactive compounds to remineralize bovine enamel subjected to erosive challenge and verify the possible correlation between the datas from the quantitative light-induced fluorescence method (QLF) and the Knoop surface microhardness test. 120 bovine enamel pieces were distributed among experimental groups with n=5 for microhardness testing (3 x 3 x 2 mm) and n=10 for the QLF method (5 x 5 x 3 mm) and were analysed at three different times (initial, after 2 days of erosion protocol and after 6 remineralizing days of treatment).The samples were subjected to two-days erosion protocol, through its immersion into 0,3% citric acid solution pH 3,2 for 2 minutes and maintaining them into artificial saliva for 24 hours (pH 7,0). Following remineralizing treatments were performed for 6 consecutive days: the samples were covered with 1 drop of saliva and after 1 hour were immersed for 2 minutes in the slurry prepared with the following materials: G1-Pro-Argin+NaMFP, arginine bicarbonate + calcium carbonate + sodium monofluorophosphate (Colgate® Sensitive Pro-Alívio); G2-Recaldent+NaF, casein phosphopeptide-amorphous calcium phosphate + sodium fluoride (MI Paste Plus); G3-ACP+NaF, amorphous calcium phosphate + sodium fluoride + potassium nitrate (Relief ACP); G4-CaGP+KF, calcium glycerophosphate + potassium fluoride (Fluor Protector Gel); G5- NovaMin®+NaF, calcium sodium phosphosilicate + sodium fluoride (Nupro® Sensodyne®); G6-NovaMin®+NaMFP, calcium sodium phosphosilicate + sodium monofluorophosphate (Sensodyne® Repair&Protect); G7-NaF, sodium fluoride + potassium nitrate (Sensodyne® Cool Gel) and G8-Artificial saliva (negative control). After 2 hours of soaking in saliva the erosion protocol was repeated. Statistical analyzes were conducted for microhardness and QLF with coincidence of the results (=0,05). A two-factors ANOVA for repeated measures showed statistically significant differences only for the time of analysis and the interaction treatments x time of analysis. The Tukey test showed statistically significant differences when comparing the three times of analysis and the interaction between times of analysis x treatments: baseline values with values after erosion and after treatment and the values after erosion x after treatment (NovaMin®+NaF, NovaMin®+NaMFP, NaF and saliva). The Tukey test when comparing the treatments x final times of analysis showed statistically significant differences in microhardness test for Recaldent+NaF x NovaMin®+NaF, NovaMin®+NaMFP and NaF; in QLF method the differences occurs between Pro-Argin+NaMFP x NaF and saliva; Recaldent+NaF x NovaMin®+NaMFP, NaF and saliva; ACP+NaF x NaF. None of the treatments was able to completely remineralize bovine enamel, but Pro-Argin+NaMFP, Recaldent+NaF, ACP+NaF and CaGP+KF materials were able to stabilize the eroding enamel, thus demonstrating a score higher than others and the QLF method showed a significant and positive correlation with the microhardness test results.

Para avaliação da resistência à fratura de dentes caninos de cães restaurados biologicamente (colagem de fragmento) foram utilizados 50 dentes distribuídos em cinco grupos de dez dentes cada. Com exceção dos dentes do grupo 1, que serviram de controle, os demais foram seccionados e posteriormente restaurados com o próprio fragmento (colagem) através de diferentes protocolos: Grupo 2: pino fundido (Níquel-Cromo) e cimento resinoso; Grupo 3: pino de fibra de vidro e cimento resinoso; Grupo 4: pino de fibra de carbono e cimento resinoso; Grupo 5: não foram utilizados pinos, apenas adesivo e resina composta fotopolimerizável (colagem simples). Os dentes foram, então, submetidos a teste de resistência através da aplicação de uma carga perpendicular ao longo eixo do dente na sua face lingual. Os resultados permitiram concluir que a utilização de pinos intra-radiculares teve influência significativa na resistência à fratura dos dentes colados quando comparada ao grupo de colagem simples, no entanto, foi de 45,4 %, 14,2%, 11,4% (respectivamente para os grupos 2, 3 e 4) da resistência necessária para fraturar os dentes íntegros, enquanto para o grupo 5 foi de 7,0 %. Dessa forma, nas condições deste experimento, os protocolos nos quais se utilizam pinos intra-radiculares parecem ser os mais indicados para colagem de dentes caninos fraturados. / To determine the fracture strength of canine teeth of dogs restored biologically (bondind of tooth fragment), 50 teeth were used and distributed in 5 groups of ten teeth each. The group 1 was the control (intact teeth). In the other groups the teeth were sectioned and bonded under different protocols: Group 2: cast post (Nickel-chromium) and resin luting cement; Group 3: Fiberglass post and resin luting cement; Group 4: Carbon fiber post and resin luting cement; Group 5: no post was used, only dentin adhesive and light-cured composite resin (simple bonding). The teeth were submitted to fracture strength test through the application of a perpendicular load to the tooth long axis in its lingual face. The results showed that the use of post improved significant fracture strength of bonding teeth when compared to the group of simple bonding, however this was 45.4%, 14.2%, 11.4% (respectively for the groups 2, 3 and 4) of the load necessary to fracture the sound teeth, whereas was it 7.0% in group 5. In these experimental conditions, the protocols where posts are used seem to be more indicated to bonding tooth fragment in fractured canine tooth.

In vivo organogenesis is based on the temporal-spatial developmental processes that depend on cell behaviour, for example on their growth, migration, differentiation and intercellular interactions. Such behaviour is regulated by appropriate transient expression of various signalling molecules. Despite the significant advances in therapeutic strategies, the secret of the development of the biological replacement of a damaged or missing tooth has not yet been revealed. In this context, animal models provide a powerful tool for studying tooth normogenesis and pathogenesis in both basic and applied research. Early development of the tooth shares similar morphological and molecular features with other ectodermal organs. At the same time, these features are largely preserved also between species, which is advantageous for the use of model organisms. The dental formula of both: the human and the mouse are reduced against a common ancestor, but both groups of organisms evince simple as well as multicusped teeth. In both, structures called rudimentary were found. These structures are suppressed during ontogenetic development and generally they are not attributed to essential functions. That is why we aimed to study dental rudiments in detail and reveal their function in odontogenesis. This work presents new...

SyfteAtt utvärdera effekterna och bieffekterna av tandblekningsprodukter innehållande eller utsöndrande av väteperoxid på permanenta tänder hos personer under 18 år. Studien gjordes med tanke på barn som drabbats av missfärgade tänder med ett objektivt och subjektivt behandlingsbehov. Detta i syfte att insamla all nuvarande forskning på området samt ställa detta mot EU-direktiven utfärdade 2012. SökstrategierEn systematisk sökning av litteraturen gjordes i databaserna Medline, Cochrane, Embase och Scopus. Inkluderade artiklar skulle vara på antingen Engelska, Svenska, Danska eller Norska. SelektionskriterierStudierna skulle vara gjorda på personer under 18 år med produkter som innehöll eller utsöndrande väteperoxid. Enbart studier på permanenta tänder inkluderades. Studierna var tvungna att utvärdera positiva och/eller negativa effekter av behandlingen. Blekningen skulle utföras in vivo. Fallrapporter inkluderades enbart i syfte att finna eventuella allvarliga bieffekter. ResultatTotalt identifierades 214 artiklar varav 13 stycken uppfyllde inkluderings- och exkluderings-kriterierna. Fyra studier bedömdes ha låg risk av bias, åtta av medelhög samt en som hög risk av bias. Syftet och studiedesignen varierade mellan de inkluderade studierna. De flesta studierna var utförda på mildare missfärgningar samtidigt som de saknade erforderliga uppföljningstider. SlutsatsDet finns inte tillräckligt med studier gjorda på personer under 18 år som utvärderar effekterna av bleking med väteperoxid på fall med mer omfattande missfärgningar. Ett begränsat antal studier med medelhög risk av bias ger ett visst stöd för blekning med väteperoxid på mildare fall av missfärgningar. Samtidigt rapporterades ett stort antal milda, övergående bieffekter. Tills motsatsen bevisats finns ett etiskt stöd för EU-direktiven etablerade 2012. / AimTo investigate the effects and adverse events of tooth whitening performed on children with permanent teeth by the use of products containing or releasing hydrogen peroxide. This was made considering children affected by objectively and subjectively observed tooth discolorations in purpose to consolidate existing research and compare it to the EU directives established 2012.Search strategiesA systematic search of the literature was conducted using the databases Medline, Cochrane, Embase and Scopus. Only studies published in English, Swedish, Danish and Norwegian were included. Selection criteriaThe selection criteria aimed to include studies performed on patients under the age of 18, using whitening products containing or releasing hydrogen peroxide. The bleaching process had to be performed in vivo on permanent teeth. Case reports were included only to be separately reviewed looking for severe side effects and adverse events.ResultsA total of 214 articles were identified and 13 met the inclusion criteria. Four papers were judged to have a low risk of bias, eight a moderate risk and one a high risk of bias. Most studies were performed on mild discolorations while they lacked in necessary follow-up times.ConclusionThere are not enough studies evaluating the effect of using hydrogen peroxide to bleach more severe discolorations on individuals under 18 years old. A limited number of studies showed some support for bleaching with hydrogen peroxide on mild tooth discolorations. Parallel to this, the included studies demonstrated a high number of mild and transient adverse events. Until proven otherwise, the lack of studies gives some ethical support to the EU-directives established 2012.