Abnormalities in Tooth Formation after Early Bisphosphonate Treatment in Children with Osteogenesis Imperfecta.

Treatment with intravenous bisphosphonate (BP) in children and adolescents with osteogenesis imperfecta (OI) started in Sweden in 1991. No human studies on the role of BP therapy in development of disturbances in tooth mineralization or tooth morphology have been published. The study cohort comprised 219 individuals who were divided into four groups: group 1, BP treatment onset before 2 years of age (n = 22); group 2, BP treatment onset between 2 and 6 years of age (n = 20); group 3, BP treatment onset between 6 and 10 years of age (n = 13); and a control group of patients with OI who had not received BP therapy (n = 164). The chi-square test was used in between-group comparisons of the prevalence of tooth agenesis. The prevalence of tooth agenesis was significantly higher in children who began BP treatment before the age of 2 years (group 1; 59%,) compared to the controls (10%; p < 0.001) and to children who had begun BP therapy between ages 2 and 6 years (group 2; 10%; p = 0.009) or between ages 6 and 10 years (group 3; 8%; p = 0.003). Different types of disturbances in the enamel formation were seen in 52 premolars, where 51 were seen in those who began BP treatment before the age of 2 years. To conclude, starting BP treatment before the age of 2 years increases the risk of abnormalities in tooth formation manifesting as morphological aberrations, tooth agenesis, and enamel defects.

Bisphosphonate Therapy and Tooth Development in Children and Adolescents with Osteogenesis Imperfecta.

Osteogenesis imperfecta (OI) is a heterogeneous connective tissue disorder characterized by repeated fractures and skeletal disorders. At present, bisphosphonate (BP) therapy is the gold standard for OI treatment. The present retrospective study evaluated the effect of BP therapy on tooth development and eruption of permanent teeth in a cohort of children receiving pamidronate. Three groups were studied: patients with OI who were treated with BPs (n = 45), patients with OI who were not treated with BPs (n = 117), and age- and gender-matched healthy controls (n = 121). Dental age, dental maturity, and tooth eruption were assessed on panoramic radiographs using the methods of Demirjian et al. (Hum Biol 45(2):211-227, 1973) and Haavikko (Suom Hammaslaak Toim 66(3):103-170, 1970) and were evaluated using the t-test, Chi-square test, and the Mann-Whitney U test. Dental age in the study group was significantly (p < 0.05) lower than chronological age compared with both control groups. Dental maturity and the eruption of permanent teeth were also significantly (p < 0.05) delayed in the study group in relation to the two control groups. The dental age was significantly lower (p < 0.001) in patients with OI type III treated with BPs compared with healthy controls and the dental maturation was significantly delayed in patients with OI type IV treated with BPs compared with those not treated. In conclusion, BP therapy in OI patients seems to lower the dental age, delay the dental maturity, and tooth eruption. BP administration before 2 years of age might be a contributing factor.

Mutations in COL1A1/A2 and CREB3L1 are associated with oligodontia in osteogenesis imperfecta.

BACKGROUND: Osteogenesis imperfecta (OI) is a heterogeneous connective tissue disorder characterized by an increased tendency for fractures throughout life. Autosomal dominant (AD) mutations in COL1A1 and COL1A2 are causative in approximately 85% of cases. In recent years, recessive variants in genes involved in collagen processing have been found. Hypodontia (< 6 missing permanent teeth) and oligodontia (≥ 6 missing permanent teeth) have previously been reported in individuals with OI. The aim of the present cross-sectional study was to investigate whether children and adolescents with OI and oligodontia and hypodontia also present with variants in other genes with potential effects on tooth development. The cohort comprised 10 individuals (7.7-19.9 years of age) with known COL1A1/A2 variants who we clinically and radiographically examined and further genetically evaluated by whole-genome sequencing. All study participants were treated at the Astrid Lindgren Children's Hospital at Karolinska University Hospital, Stockholm (Sweden's national multidisciplinary pediatric OI team). We evaluated a panel of genes that were associated with nonsyndromic and syndromic hypodontia or oligodontia as well as that had been found to be involved in tooth development in animal models. RESULTS: We detected a homozygous nonsense variant in CREB3L1, p.Tyr428*, c.1284C > A in one boy previously diagnosed with OI type III. COL1A1 and COL1A2 were the only two genes among 9 individuals which carried a pathogenic mutation. We found rare variants with unknown significance in several other genes related to tooth development. CONCLUSIONS: Our findings suggest that mutations in COL1A1, COL1A2, and CREB3L1 may cause hypodontia and oligodontia in OI. The findings cannot exclude additive effects from other modifying or interacting genes that may contribute to the severity of the expressed phenotype. Larger cohorts and further functional studies are needed.

Guidelines for the Management of Traumatic Dental Injuries: 1. Fractures and Luxations of Permanent Teeth.

Traumatic dental injuries (TDIs) of permanent teeth occur frequently in children and young adults. Crown fractures and luxations are the most commonly occurring of all dental injuries. Proper diagnosis, treatment planning and followup are important for improving a favorable outcome. Guidelines should assist dentists and patients in decision making and for providing the best care effectively and efficiently. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the best current evidence based on literature search and professional opinion. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care of TDIs. In this first article, the IADT Guidelines for management of fractures and luxations of permanent teeth will be presented.

Guidelines for the Management of Traumatic Dental Injuries: 2. Avulsion of Permanent Teeth.

Avulsion of permanent teeth is one of the most serious dental injuries, and a prompt and correct emergency management is very important for the prognosis. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the task group. The guidelines represent the current best evidence and practice based on literature research and professionals' opinion. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate orurgent care of avulsed permanent teeth.

Guidelines for the Management of Traumatic Dental Injuries: 3. Injuries in the Primary Dentition.

Traumatic injuries to the primary dentition present special problems and the management is often different as compared with the permanent dentition. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialities were included in the task group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care for management of primary teeth injuries. The IADT cannot and does not guarantee favorable outcomes from strict adherence to the guidelines, but believe that their application can maximize the chances of a positive outcome.

Mutations in COL1A1 and COL1A2 and dental aberrations in children and adolescents with osteogenesis imperfecta - A retrospective cohort study.

Osteogenesis imperfecta (OI) is a heterogeneous group of disorders of connective tissue, caused mainly by mutations in the collagen I genes (COL1A1 and COL1A2). Dentinogenesis imperfecta (DGI) and other dental aberrations are common features of OI. We investigated the association between collagen I mutations and DGI, taurodontism, and retention of permanent second molars in a retrospective cohort of 152 unrelated children and adolescents with OI. The clinical examination included radiographic evaluations. Teeth from 81 individuals were available for histopathological evaluation. COL1A1/2 mutations were found in 104 individuals by nucleotide sequencing. DGI was diagnosed clinically and radiographically in 29% of the individuals (44/152) and through isolated histological findings in another 19% (29/152). In the individuals with a COL1A1 mutation, 70% (7/10) of those with a glycine substitution located C-terminal of p.Gly305 exhibited DGI in both dentitions while no individual (0/7) with a mutation N-terminal of this point exhibited DGI in either dentition (p = 0.01). In the individuals with a COL1A2 mutation, 80% (8/10) of those with a glycine substitution located C terminal of p.Gly211 exhibited DGI in both dentitions while no individual (0/5) with a mutation N-terminal of this point (p = 0.007) exhibited DGI in either dentition. DGI was restricted to the deciduous dentition in 20 individuals. Seventeen had missense mutations where glycine to serine was the most prevalent substitution (53%). Taurodontism occurred in 18% and retention of permanent second molars in 31% of the adolescents. Dental aberrations are strongly associated with qualitatively changed collagen I. The varying expressivity of DGI is related to the location of the collagen I mutation. Genotype information may be helpful in identifying individuals with OI who have an increased risk of dental aberrations.

Guidelines for the Management of Traumatic Dental Injuries: 1. Fractures and Luxations of Permanent Teeth.

Traumatic dental injuries (TDIs) of permanent teeth occur frequently in children and young adults. Crown fractures and luxations are the most commonly occurring of all dental injuries. Proper diagnosis, treatment planning and followup are important for improving a favorable outcome. Guidelines should assist dentists and patients in decision making and for providing the best care effectively and efficiently. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the best current evidence based on literature search and professional opinion. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care of TDIs. In this first article, the IADT Guidelines for management of fractures and luxations of permanent teeth will be presented.

Guidelines for the Management of Traumatic Dental Injuries: 2. Avulsion of Permanent Teeth.

Avulsion of permanent teeth is one of the most serious dental injuries, and a prompt and correct emergency management is very important for the prognosis. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the task group. The guidelines represent the current best evidence and practice based on literature research and professionals' opinion. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate orurgent care of avulsed permanent teeth.

Guidelines for the Management of Traumatic Dental Injuries: 3. Injuries in the Primary Dentition.

Traumatic injuries to the primary dentition present special problems and the management is often different as compared with the permanent dentition. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialities were included in the task group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care for management of primary teeth injuries. The IADT cannot and does not guarantee favorable outcomes from strict adherence to the guidelines, but believe that their application can maximize the chances of a positive outcome.

Scandinavian multicenter study on the treatment of 168 patients with 230 intruded permanent teeth - a retrospective cohort study.

BACKGROUND/AIM: The aim of the study was to evaluate the survival of intruded permanent teeth related to treatment in a large number of patients, with special focus on development of pulp necrosis and replacement resorption (ankylosis-related resorption). MATERIALS AND METHODS: The material consisted of 168 patients (mean age 9.6 years) with 230 intruded permanent teeth from dental trauma clinics in Copenhagen, Denmark, Stockholm, Sweden, and Oslo, Norway. The degree of intrusion was classified as mild (1-<3 mm), moderate (3-7 mm), and severe (>7 mm). Root development was categorized with respect to root formation and development of the apex into three groups of increasing tooth maturity: very immature, immature, and mature. RESULTS: Awaiting re-eruption was the treatment of choice in 107 teeth (47%), orthodontic repositioning in 28 (12%) and surgical repositioning in 95 (41%) teeth. Pulp necrosis was diagnosed in 173 teeth (75%), infection-related root resorption in 57 (25%) and replacement resorption in 50 teeth (22%). Very immature teeth, teeth diagnosed with mild intrusion, and teeth awaiting re-eruption had significantly (P < 0.05) fewer complications. In a stepwise discriminant function analysis, choice of treatment, root development, and degree of intrusion were significantly (P < 0.05) associated with the development of replacement resorption. Root development and degree of intrusion were significantly (P < 0.05) associated with the development of pulp necrosis. CONCLUSION: This study indicates that root development and degree of intrusion may be important for the development of pulp necrosis as well as replacement resorption, whereas choice of treatment only seems to influence the development of replacement resorption in intruded permanent teeth. Awaiting re-eruption resulted in the lowest risk for developing replacement resorption.

Genetic epidemiology, prevalence, and genotype-phenotype correlations in the Swedish population with osteogenesis imperfecta.

Osteogenesis imperfecta (OI) is a rare hereditary bone fragility disorder, caused by collagen I mutations in 90% of cases. There are no comprehensive genotype-phenotype studies on >100 families outside North America, and no population-based studies determining the genetic epidemiology of OI. Here, detailed clinical phenotypes were recorded, and the COL1A1 and COL1A2 genes were analyzed in 164 Swedish OI families (223 individuals). Averages for bone mineral density (BMD), height and yearly fracture rate were calculated and related to OI and mutation type. N-terminal helical mutations in both the α1- and α2-chains were associated with the absence of dentinogenesis imperfecta (P<0.0001 vs 0.0049), while only those in the α1-chain were associated with blue sclera (P=0.0110). Comparing glycine with serine substitutions, α1-alterations were associated with more severe phenotype (P=0.0031). Individuals with type I OI caused by qualitative vs quantitative mutations were shorter (P<0.0001), but did not differ considering fractures or BMD. The children in this cohort were estimated to represent >95% of the complete Swedish pediatric OI population. The prevalence of OI types I, III, and IV was 5.16, 0.89, and 1.35/100 000, respectively (7.40/100 000 overall), corresponding to what has been estimated but not unequivocally proven in any population. Collagen I mutation analysis was performed in the family of 97% of known cases, with causative mutations found in 87%. Qualitative mutations caused 32% of OI type I. The data reported here may be helpful to predict phenotype, and describes for the first time the genetic epidemiology in >95% of an entire OI population.

Long-term follow up of 103 ankylosed permanent incisors surgically treated with decoronation--a retrospective cohort study.

BACKGROUND/AIM: Decoronation is a technique developed in 1984 to remove ankylosed teeth and increase marginal bone levels in young, growing individuals. This retrospective cohort study evaluates marginal bone development after decoronation in relation to gender and age at treatment. MATERIALS AND METHODS: The study evaluated all 95 patients with 103 ankylosed permanent incisors treated with decoronation at the Eastmaninstitutet Department of Pediatric Dentistry during 1978-1999. Mean age of the patients was 10.7 years (6.8-17.8) at the time of trauma and 14.9 years (9.3-22.0) at decoronation. The mean follow-up period was 4.6 years (1.0-19.3 years). The study evaluated development of the marginal alveolar bone level with a three-point scoring system: 1 = Unchanged or reduced alveolar bone level, 2 = A moderate increase in alveolar bone level, and 3 = A considerable increase in alveolar bone level. The final group for statistical evaluation comprised 75 patients: 56 boys and 19 girls who had only one tooth decoronated. Kappa statistics showed almost complete agreement between the two observers (κ = 0.90). RESULTS: Bone level changes were significantly correlated (P < 0.05) to gender and age at treatment. In decoronations performed after the age of 16, bone levels were unchanged or reduced, while decoronations performed at a mean age of 14.6 years in boys and 13 years in girls yielded a considerable increase in bone levels. CONCLUSION: This study indicates that age at decoronation is an important factor for favorable development of the alveolar ridge and that decoronation should be performed earlier in girls.

The effect of topical treatment with doxycycline compared to saline on 66 avulsed permanent teeth--a retrospective case-control study.

BACKGROUND/AIM: Tooth avulsion in young growing individuals is an uncommon but very severe dental trauma. The aim of this retrospective case-control study was to evaluate the effect of topical treatment with doxycycline on avulsed permanent teeth compared with treatment with only saline regarding pulp survival and periodontal healing. MATERIAL AND METHOD: Sixty-six avulsed teeth in 50 patients (34 boys and 16 girls) between the ages six and 18 years were included in this study. Thirty teeth were soaked in a 0.05 mg ml(-1) doxycycline solution for 5 min, before replantation and 36 teeth in saline solution. Root development was categorized with respect to root formation and development of the apex into three groups, one-half-root formation to full root formation with open apex, full root formation with half-closed apex and full root formation with closed apex. Pulp survival and periodontal healing were assessed as successful when at the end of the observation period no pulp necrosis or ankylosis-related resorption was diagnosed. The mean observation time was 48 months. RESULTS: In the doxycycline group, 27 were diagnosed with pulp necrosis, 15 with ankylosis-related resorption and nine were extracted. In the saline group, 30 were diagnosed with pulp necrosis, 23 with ankylosis-related resorption and 11 were extracted. Regarding pulp survival and periodontal healing, no significant differences were found between the two groups. Teeth with immature root development showed significantly less pulp necrosis (P < 0.05) compared to teeth with full root formation regardless if treated topically with doxycycline or not. No significant differences were found between the two groups regarding age, storage, root development, splinting duration and observation time although the saline group had significantly longer extra-oral time (P < 0.001) than the doxycycline group. CONCLUSIONS: This study indicates that avulsed permanent teeth soaked in doxycycline do not show a better treatment outcome regarding pulp survival and periodontal healing compared with avulsed teeth placed only in saline solution. This finding is consistent regardless of root development, storage and extra-oral time.

Ridge preservation/decoronation.

Dentoalveolar ankylosis of a tooth is a serious complication in growing individuals. The ankylosed root is continuously resorbed and replaced by bone, and an infraposition of the damaged tooth will develop. The normal alveolar development will be disrupted in this way, and prosthetic treatment will be compromised. Therefore, an ankylosed tooth should be removed before future orthodontic and/or prosthetic therapy is jeopardized. This article will present a method, decoronation, to remove an ankylosed tooth in such a way that the alveolar ridge is preserved and give guidelines for the timing to intervene. The decoronation method is described, and a possible explanation for the favorable outcome is discussed. Different aids to decide the time for intervention are presented. The alveolar ridge was maintained in buccal/palatinal direction, and the bone level increased after decoronation in patients treated before or during pubertal growth periods. The bone level also increased in those treated after this period but not at the same rate, and in a few patients it was unchanged. The clinical finding that decoronation can maintain or reestablish normal alveolar conditions is important for successful implant insertion later.

Ridge preservation/decoronation.

Dentoalveolar ankylosis of a tooth is a serious complication in growing individuals. The ankylosed root is continuously resorbed and replaced by bone, and an infraposition of the damaged tooth will develop. The normal alveolar development will be disrupted in this way, and prosthetic treatment will be compromised. Therefore, an ankylosed tooth should be removed before future orthodontic and/or prosthetic therapy is jeopardized. This article will present a method, decoronation, to remove an ankylosed tooth in such a way that the alveolar ridge is preserved and give guidelines for the timing to intervene. The decoronation method is described, and a possible explanation for the favorable outcome is discussed. Different aids to decide the time for intervention are presented. The alveolar ridge was maintained in buccal/palatinal direction, and the bone level increased after decoronation in patients treated before or during pubertal growth periods. The bone level also increased in those treated after this period but not at the same rate, and in a few patients it was unchanged. The clinical finding that decoronation can maintain or reestablish normal alveolar conditions is important for successful implant insertion later.

International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 3. Injuries in the primary dentition.

Traumatic injuries to the primary dentition present special problems and the management is often different as compared with the permanent dentition. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialities were included in the task group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care for management of primary teeth injuries. The IADT cannot and does not guarantee favorable outcomes from strict adherence to the guidelines, but believe that their application can maximize the chances of a positive outcome.

International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 2. Avulsion of permanent teeth.

Avulsion of permanent teeth is one of the most serious dental injuries, and a prompt and correct emergency management is very important for the prognosis. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the task group. The guidelines represent the current best evidence and practice based on literature research and professionals' opinion. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care of avulsed permanent teeth.

International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 1. Fractures and luxations of permanent teeth.

Traumatic dental injuries (TDIs) of permanent teeth occur frequently in children and young adults. Crown fractures and luxations are the most commonly occurring of all dental injuries. Proper diagnosis, treatment planning and followup are important for improving a favorable outcome. Guidelines should assist dentists and patients in decision making and for providing the best care effectively and efficiently. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the best current evidence based on literature search and professional opinion. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care of TDIs. In this first article, the IADT Guidelines for management of fractures and luxations of permanent teeth will be presented.