[Molecular mechanisms of odontogenesis]

[Comparative characteristics of root formation and mineralization features in the permanent teeth according to cone beam computed tomography data]

AIM

Studying features of root formation and mineralization in permanent teeth of children and adults.

MATERIAL AND METHODS

The root formation features were studied in 2800 children's permanent teeth aged 6-15 in Moscow and Moscow region; cone beam computed tomography was performed according to the orthodontic indications. CBCT method was also used to study the apical foramen diameter, width of the permanent teeth periodontal fissure, perform clinical examination and treatment of youngsters and young people (aged 12-25, n=180) with pulpitis (K04.03), apical periodontitis (K04.5) and uncompleted processes of hard tissues mineralization and hard tissues with different degrees of maturation; as well as groups of adults (aged 30-50, n=170) with pulpitis (K04.03) and apical periodontitis (K04.5) in permanent teeth with completed processes of hard tissues mineralization.

RESULTS

CBCT is objective for visualizing teeth of both jaws which allows determining root formation stages in children's permanent teeth and high precision during one examination visit. Teeth Youngster's and young peopl's teeth have expressed anatomical and structural features during 5-6 years after root formation completion: apical foramen diameter of 0.71±0.004 mm, periodontal fissure width of 1.01±0.004 mm, hard tissues density in apical part of root is 12282.71 units HU, which is different from analogous readings in people over 25 where they make 0.61±0.004 mm (p<0.05); 0.71±0.003 mm (p<0.05); 1428.6±0.89 units HU (p<0.05) respectively.

CONCLUSION

CBCT is a useful tool for visualization of dental roots allowing precise definition of root developmental stage in permanent teeth in children by one diagnostic imaging procedure.

[Phantom root as dental trauma complication in immature teeth (systematic literature and clinical cases review)]

The paper presents literature review and the analysis of three clinical cases of phantom root development. Phantom root is a rare complication occurring as a result of apical papilla detachment, usually after dental trauma. Some authors suggest regenerative endodontic procedure may contribute to phantom root development because of rude intervention in periapical tissues needed to induce apical bleeding required for intracanal blood clot formation. Phantom root is not an indication for endodontic treatment. The prognosis depends on initial root formation stage and root to crow length ratio at the time of trauma. In the majority of cases the teeth may be preserved, but continuous root development is not to be expected.

[Perinatal risk factors of the early childhood caries]

THE AIM

Of the study was to find possible correlations between early childhood caries (ECC) prevalence and intensity and perinatal factors, such as pregnancy and birth adverse events, terms and mode of delivery, child's weight at birth.

MATERIALS AND METHODS

The study comprised 165 3-6 years old healthy children (80 boys and 85 girls) examined in Khimki nurseries. Perinatal background data were collected through validated questionnaires.

RESULTS

ECC prevalence and dmft median were 41.2% and 1.2 teeth, correspondingly, in 3-years-olds and values growth up to 64.8% and 3.5 teeth was seen in 6-years-olds. Exact Fisher test showed significant positive correlation between adverse pregnancy events and caries risk, as ECC had 8.6 and 51.7% of children born from complicated and non-complicated pregnancies, correspondingly (p<0.05). In children born by cesarean section ECC was detected more often, than in born via vaginal delivery (62.8 vs 49.6%, correspondingly). The correlation became statistically significant by the age of 6 (p=0.02). In 6-years-olds we also noted significant correlation between mode of delivery and dmft numbers (p<0.05).

CONCLUSION

Adverse pregnancy events and cesarean section are ECC risk factor affecting the intensity of the disease.