Rethinking isolated cleft lip and palate as a syndrome.

OBJECTIVE: The goal of the present work was to use dental conditions that have been independently associated with cleft lip and palate (CL/P) as a tool to identify a broader collection of individuals to be used for gene identification that lead to clefts. STUDY DESIGN: We studied 1573 DNA samples combining individuals that were born with CL/P or had tooth agenesis, supernumerary teeth, molar incisor hypomineralization, or dental caries with the goal to identify genetic associations. We tested 2 single-nucleotide polymorphisms that were located in the vicinity of regions suggested to contribute to supernumerary teeth. Overrepresentation of alleles were determined for combinations of individuals as well as for each individual phenotypic group with an α of .05. RESULTS: We determined that the allele C of rs622260 was overrepresented in all individuals studied compared with a group of unrelated individuals who did not present any of the conditions described earlier. When subgroups were tested, associations were found for individuals with hypomineralization. CONCLUSIONS: Although we did not test this hypothesis directly in the present study, based on associations reported previously, we believe that CL/P is actually a syndrome of alterations of the dentition, and considering it that way may allow for the identification of genotype-phenotype correlations that may be useful for clinical care.

What is the Best Root Surface Treatment for Avulsed Teeth?

Dental avulsion is the most severe type of traumatic tooth injuries since it causes damage to several structures and results in avulsion of the tooth from its socket. Management protocols for avulsed teeth should include management of the pulp and periodontal ligament (PDL) cells in order to improve the long-term prognosis and survival of these teeth. The prognosis of the treatment as well as the survival of an avulsed tooth depends on intrinsic and extrinsic factors, such as the duration of the tooth's extra-alveolar period, replantation time, the type of storage medium, PDL status and duration of splinting. Recent research has led to the development of storage media. However, there is not yet a single solution that fulfills all requirements to be considered as the ideal medium for temporary storage of avulsed teeth, and research on this field should carry on. On the other hand in case of delayed replantation, due to the great risk of tooth loss after avulsion, different root surface treatments have been proposed to prevent and delay root resorption before replantation. For this purpose, researchers have applied some different root surface treatment modalities in delayed replantation of avulsed teeth. Several protocols have been used to maintain PDL viability; some involve fluorides, steroids, sodium alendronate, enamel matrix derivatives (EMD) and basic fibroblast growth factor (bFGF, FGF-2). Among these applications, bFGF shows promising results in the regeneration of natural tooth structures and tissues. Better understanding of mechanism of bFGF may help to improve new technologies of regeneration of tooth structures.

Traumatic dental injuries in Turkish children, Istanbul.

AIM: Some of the commonly encountered dental emergencies are traumatic dental injuries. The aim of this study was to evaluate traumatic dental injuries with regard to age, gender, etiology, classification of trauma, teeth involved, place of injury, and treatment received by patients who were referred over a 2-year period to the Istanbul University, Faculty of Dentistry, Clinics of Pedodontics, Istanbul, Turkey. MATERIALS AND METHODS: The study was based on the clinical data of 154 patients (337 traumatized teeth). The children were examined clinically for dental injuries by the same investigator. The following information was recorded: age, gender, etiology, localization, place, number of injured teeth, type of trauma, type of tooth, time elapsed between injury and treatment, and treatment provided. Traumatized teeth were assessed according to the classification of the World Health Organization slightly modified. RESULTS: A total of 154 patients aged 1-13 years presented a total of 337 traumatized teeth (255 permanent and 82 primary). 94 boys (61%) and 60 girls (39%) with a mean age of 7.91 ± 3.15 years participated in the study. Dental injuries were frequent in the 6-12 year age group. The most common type of dental injuries recorded was luxation injuries (43.3%), uncomplicated crown fractures (20.5%), and complicated crown fractures (19.4%). The main causes were falls (55.2%) and being struck by an object (22.1%). The most frequent treatment was examination only (31.8%). CONCLUSIONS: In childhood, a correct diagnosis may affect the management methods and prevent the occurrence of complications after treatment for traumatic dental injuries. Therefore, continuing education programs offering the latest updates in the management of traumatized teeth should be provided for dental and medical practitioners.

Genes expressed in dental enamel development are associated with molar-incisor hypomineralization.

Genetic disturbances during dental development influence variation of number and shape of the dentition. In this study, we tested if genetic variation in enamel formation genes is associated with molar-incisor hypomineralization (MIH), also taking into consideration caries experience. DNA samples from 163 cases with MIH and 82 unaffected controls from Turkey, and 71 cases with MIH and 89 unaffected controls from Brazil were studied. Eleven markers in five genes [ameloblastin (AMBN), amelogenin (AMELX), enamelin (ENAM), tuftelin (TUFT1), and tuftelin-interacting protein 11 (TFIP11)] were genotyped by the TaqMan method. Chi-square was used to compare allele and genotype frequencies between cases with MIH and controls. In the Brazilian data, distinct caries experience within the MIH group was also tested for association with genetic variation in enamel formation genes. The ENAM rs3796704 marker was associated with MIH in both populations (Brazil: p=0.03; OR=0.28; 95% C.I.=0.06-1.0; Turkey: p=1.22e-012; OR=17.36; 95% C.I.=5.98-56.78). Associations between TFIP11 (p=0.02), ENAM (p=0.00001), and AMELX (p=0.01) could be seen with caries independent of having MIH or genomic DNA copies of Streptococcus mutans detected by real time PCR in the Brazilian sample. Several genes involved in enamel formation appear to contribute to MIH.

Craniofacial and dental characteristics of Goldenhar syndrome: a report of two cases.

We describe the dental and craniofacial anomalies of 2 ethnically distinct patients with Goldenhar syndrome, which is characterized by hemifacial microsomia, facial asymmetry, and ear and dental abnormalities. A 7-year-old Japanese girl and 12-year-old Turkish boy with Goldenhar syndrome were examined clinically and radiographically; both had symptoms of hemifacial microsomia. Multiple organ involvement can limit surgical correction of deformities and affect patient management. Therefore, long-term regular follow-up by a multidisciplinary team is important to monitor the growth and development of patients.

Dental implant systems.

Among various dental materials and their successful applications, a dental implant is a good example of the integrated system of science and technology involved in multiple disciplines including surface chemistry and physics, biomechanics, from macro-scale to nano-scale manufacturing technologies and surface engineering. As many other dental materials and devices, there are crucial requirements taken upon on dental implants systems, since surface of dental implants is directly in contact with vital hard/soft tissue and is subjected to chemical as well as mechanical bio-environments. Such requirements should, at least, include biological compatibility, mechanical compatibility, and morphological compatibility to surrounding vital tissues. In this review, based on carefully selected about 500 published articles, these requirements plus MRI compatibility are firstly reviewed, followed by surface texturing methods in details. Normally dental implants are placed to lost tooth/teeth location(s) in adult patients whose skeleton and bony growth have already completed. However, there are some controversial issues for placing dental implants in growing patients. This point has been, in most of dental articles, overlooked. This review, therefore, throws a deliberate sight on this point. Concluding this review, we are proposing a novel implant system that integrates materials science and up-dated surface technology to improve dental implant systems exhibiting bio- and mechano-functionalities.