Pediatric Dental Journal最新文献

Background

Regional odontodysplasia is a rare developmental anomaly usually affecting maxillary anterior region. We reported clinical observation in relation to two cases of regional odontodysplasia as the first report (Ped Dent J 2020; 30:124–128). There are only a few studies that have reported the detailed histological structure of teeth affected by odontodysplasia. The purpose of this report was to explore histologically the primary teeth affected by odontodysplasia in the two cases.

Materials and methods

The subjects of this study were two primary teeth with odontodysplasia reported as the first report, upper right primary lateral incisor of case1 and upper right primary first molar of case 2. These affected teeth were observed using stereo microscope, high resolution X-ray CT scanner (Micro CT), optical microscope and electron beam probe microanalyzer (EPMA).

Result

The surface of both teeth was rough and the volume of enamel was small at the hypoplastic areas. Histological findings revealed that enamel rods as well as dentinal tubules were unclear and that the volume of minerals in enamel was low in the case 1.

Conclusion

Detailed histological observation revealed that enamel and dentine were hypoplastic. It was suggested that tooth germ formation began normally, but problems occurred in cell differentiation stages of teeth affected by odontodysplasia. Moreover, hypocalcification was more severe in the primary anterior tooth than the primary molar.

Background

We report a case of idiopathic internal resorption in primary canines and molars.

Case Presentation

A Japanese boy aged 4 years 0 months with no history of orofacial trauma was referred for a fracture in the crown of the maxillary right primary canine with exposed pulp. Internal resorption was diagnosed, and pulp treatment was performed to preserve the tooth from further resorption. Consequently, internal resorption was found in five primary teeth within 18 months during follow-up appointments.

Conclusion

In patients with idiopathic internal resorption seen in multiple primary teeth, short-term follow-up examinations and treatment for tooth preservation should be performed.

Objectives

This study aimed to clarify effective eye movement patterns during mixed dentition panoramic radiographic reading in dental students.

Methods

Sixty fifth-year dental students (19 women and 41 men) participated in the study and visually observed mixed dentition panoramic radiograph. Eye movement patterns during reading were classified into group R for clockwise (right rotation), group L for counterclockwise (left rotation), or group S for few fixations and mainly saccades. The reading results, number of fixations, number of blinks, pupil area, and average amplitude were compared among the three groups.

Results

Participants in group R had significantly better reading performance (P < 0.001, analysis of variance) and tended to have larger pupil areas than the other groups. Participants in group S had poorer reading performance, significantly fewer fixations, significantly more blinks, smaller pupil area, and greater average amplitude than the other groups (P < 0.001, respectively, analysis of variance, Kruskal–Wallis test).

Conclusions

When reading panoramic radiographs in the mixed dentition phase, observations in a clockwise order are recommended, as they are associated with improved learning performance. Frequent eye movements may indicate lower levels of interest or difficulty with the task and are associated with poorer learning performance. Classifying eye movement patterns while observing a test image provides suggestions that can be used to improve education in diagnostic imaging of pediatric dentistry.

Background

Osteopetrosis is a rare skeletal disease characterized by increased bone density caused by a malfunction of osteoclasts.

Case presentation

An 8-year-4-month-old girl with multiple primary and permanent tooth impaction was diagnosed with osteopetrosis. In spite of typical manifestations of osteopetrosis in early childhood, including visual and hearing impairments, short stature, and dental abnormalities, diagnosis was severely delayed.

Conclusion

Multiple impacted teeth may indicate a possible diagnosis of osteopetrosis. Dentists should perform an orthopantomography examination when eruption disturbances are encountered and systemic disease should also be suspected, with referral to a pediatrician when necessary.

Background

Simultaneous Activation Technique is a newer method of co-curing resin modified glass ionomer (RMGI) and self-etch adhesive.

Aim

Assessment of microleakage and interfacial adaptation following simultaneous activation technique in primary molars.

Design

Standardized Class I cavities were prepared in 66 non-carious primary molars and randomly allocated to Group I – Simultaneous activation of RMGI and self-etch adhesive (SAT); Group II – SAT with enamel etching (SAT + EE); Group III – Conventional Sandwich Technique (ST) and restored with bulk fill composite. Time taken was calculated using stopwatch. Microleakage was assessed using dye penetration method under stereomicroscope. Seven samples per group were sent for Scanning Electron Microscopy (SEM) analysis. One-Way Analysis of Variance and Post- Hoc Tukey's test were applied at P < 0.05.

Results

Mean microleakage of group I, II and III were 1.23, 1.41 and 1.59 respectively. Time taken was least for SAT followed by SAT + EE and ST group. Statistically significant difference was seen between SAT and ST group (p < 0.0001) and SAT + EE and ST group (p < 0.0001). SEM analysis showed better mean interfacial adaptation in SAT + EE (1.00) followed by ST (2.14) and SAT (3.57) group. Difference between SAT + EE and SAT group was significant (p = 0.005).

Conclusion

Simultaneous activation technique with selective enamel etching resulted in less microleakage and better interfacial adaptation.

Giant cell fibroma (GCF), a benign fibrous proliferation, represents about 4.7% of all benign/reactive fibrous growths in the oral cavity. GCF preferentially affects Caucasians, with a peak incidence in the third decade of life, and slight female predilection. Clinically, small gingival nodules (about 1.0 cm in diameter) are often observed. Herein, we report a 5-year-old girl who was referred for evaluation of a pedunculated nodule on the gingiva, resembling a human papillomavirus (HPV)-associated papillary lesion clinically and microscopically. HPV was not detected by immunohistochemical and in situ hybridization analysis in the excised surgical specimen. Thus, the lesion was diagnosed as GCF. Papillary surface projections are rarely described in GCF, but it should be included in its clinicopathological spectrum, especially in pediatric patients.

Objectives

This study aimed to clarify the effect of palatine tonsil hypertrophy-induced ventilation obstruction on maxillofacial dentition morphology using computational fluid dynamics (CFD) to represent tongue posture and maxillofacial dentition three dimensionally.

Materials and methods

We analyzed data of 20 patients with tonsil hypertrophy (tonsil hypertrophy group (TG); 9.0 years old, seven boys) and a comparison group (CG) of 20 patients without tonsil hyperplasia (comparison group; 9.4 years old, 10 boys). Cone-beam computed tomography and CFD data were used to assess the effects of palatine tonsil hypertrophy on pharyngeal airway ventilation, tongue posture, and morphology of the maxillofacial dentition.

Results

The TG exhibited significantly greater depth, narrower width, smaller cross-sectional area of the pharyngeal airway, and narrower maxillary dental arch with Class II than the CG. Additionally, the tongue was positioned significantly more anteriorly and inferiorly in the TG than that in the CG.

Conclusions

Our data suggest that hypertrophy of the palatine tonsils narrows the pharyngeal airway, resulting in a smaller cross-sectional area. Widening of the pharyngeal airway may occur due to compensatory anterior displacement of the tongue to prevent ventilation obstruction. This may decrease palatal support, disturbing the pressure balance of the maxillary molar region between the buccal and palatal sides and resulting in lateral undergrowth of the maxillary bone and narrowing of the maxillary dental arch.

Objectives

White spot lesions (WSLs) are frequently observed on young permanent teeth. The aim of this clinical study was to evaluate the remineralizing effect of paste and a mouthguard containing surface pre-reacted glass-ionomer (S-PRG) filler by observing and measuring lesion area.

Materials and methods

A total of 14 children (age range, 8–16 years) with WSLs involving 74 teeth attending Asahi University Medical & Dental Center were examined. Color- and size-matching stickers (Cas Match™, Bear Medic) were photographed with involved teeth. Mouthguards made of an S-PRG filler-containing ethylene-vinyl acetate sheet (sample; SHOFU) with S-PRG filler-containing paste (PRG Pro-Care Gel®; SHOFU) (PRG MG-Paste group) or without paste (PRG MG group; control) were applied to WSLs at bedtime.

Results

No teeth required restoration due to caries progression during the experimental period. Mean reductions in lesion area at 6 months after treatment in the PRG MG-Paste group and PRG MG group were 1.66 ± 1.84 mm² and 0.81 ± 1.27 mm², respectively. Significant differences were observed between groups (p < 0.05). No significant difference in area reduction was seen between kinds of teeth involved, although significant differences in area reduction were observed among individual subjects.

Conclusion

These results suggest that combined use of S-PRG filler-containing paste and a mouthguard is effective for remineralization of WSLs observed on numerous teeth.

Aim

We have previously reported that questionnaires and tongue pressure measurements are useful in the study of developmental insufficiency of oral function (DIOF). This study aimed to characterize the masticatory muscle activity of DIOF in children using electromyography to contribute to the future diagnosis and treatment of the disease.

Methods

This study included 41 children (16 boys and 25 girls) aged 5–6 years. A cordless electromyograph was attached to the shallow masseter muscle, and the participants freely chewed the chewing check gum 60 times in the chair-sitting position. The activity of the masseter muscle was recorded for 60 bites.

Results

The chewing cycle, maximal peak interval, and right-sided masseter muscle were found to be predominantly lower in the DIOF group than in the non-DIOF group. No significant differences were observed in the duration of chewing time and chewing interval between the two groups.

Conclusions

The electromyography measurements, as well as the comparison of muscle activity between the working and non-working sides, were found to be useful for the evaluation and treatment of DIOF.

Objectives

To examine the relationship between Adverse Childhood Experiences (ACEs) and utilization and delay of dental care among children.

Methods

Using data from the 2018–2019 National Survey of Children's Health (n = 53,963) we examined the association between ACEs and 1) dental health; 2) use of dental care; 3) use of preventive dental care; 4) delaying needed dental care. Logistic regressions were used to calculate odds of each outcome, with nine ACEs and the cumulative number of ACEs as the independent variables each in separate models.

Results

After accounting for confounders, most ACEs were associated with higher odds of having poorer dental health. Similarly, most ACEs were associated with lower odds of using dental care and higher odds of delaying needed dental care.

Conclusions

This study expands the research showing a deleterious impact of ACEs on utilization of health care by showing that dental care is also adversely impacted. Efforts must be undertaken to improve access to dental care for children with a history of ACEs.