Objective: To test the null hypothesis that there is no relationship between infraocclusion and the occurrence of other dental anomalies in subjects selected for clear-cut infraocclusion of one or more deciduous molars. Materials and Methods: The experimental sample consisted of 99 orthodontic patients (43 from Boston, Mass, United States; 56 from Jerusalem, Israel) with at least one deciduous molar in infraocclusion greater than 1 mm vertical discrepancy, measured from the mesial marginal ridge of the first permanent molar. Panoramic radiographs and dental casts were used to determine the presence of other dental anomalies, including agenesis of permanent teeth, microdontia of maxillary lateral incisors, palatally displaced canines (PDC), and distal angulation of the mandibular second premolars (MnP2-DA). Comparative prevalence reference values were utilized and statistical testing was performed using the chi-square test (P , .05) and odds ratio. Results: The studied dental anomalies showed two to seven times greater prevalence in the infraocclusion samples, compared with reported prevalence in reference samples. In most cases, the infraoccluded deciduous molar exfoliated eventually and the underlying premolar erupted spontaneously. In some severe phenotypes (10%), the infraoccluded deciduous molar was extracted and space was regained to allow uncomplicated eruption of the associated premolar. Conclusion: Statistically significant associations were observed between the presence of infraocclusion and the occurrence of tooth agenesis, microdontia of maxillary lateral incisors, PDC, and MnP2-DA. These associations support a hypothesis favoring shared causal genetic factors. Clinically, infraocclusion may be considered an early marker for the development of later appearing dental anomalies, such as tooth agenesis and PDC. (Angle Orthod. 2010;80:440-445.)

The aim of the study was to establish the prevalence of dental features that indicate a need for early orthodontic treatment (EOT). A group of schoolchildren in the mixed dentition stage (7-11 years old) (n = 432) was clinically screened for indications for EOT. Over 1/3 of the youngsters (34.7 per cent) presented at least one of the indications for EOT: anterior and posterior crossbites (including edge to edge occlusion) were found in 9.5 and 23.3 per cent, respectively; Angle Class III was found in 3 per cent; increased overjet (≥7 mm) prevailed in 3.7 per cent and was significantly related to risk for dental trauma (P = 0.001); while oral habits were practiced by 10.9 per cent, open bite was found only in 6.5 per cent, both predominantly among girls (P = 0.006 and P = 0.012, respectively); impinging overbite was present in 5.2 per cent, mainly in boys (P = 0.006); crowding >5 mm was found in 6.9 per cent for the maxilla and in 6 per cent for the mandible. Loss of tooth material affecting tooth position was found in 15.3 per cent. Normal occlusal relationships were found in 10.9 per cent only. The findings indicate that almost 1/3 of the examined children in the mixed dentition stage require EOT. Sexual dimorphism was demonstrated for several occlusal features.

Background: Streptococcus mutans (S. mutans) and Candida albicans (C. albicans) are two major contributors to dental caries. They have a symbiotic relationship, allowing them to create an enhanced biofilm. Our goal was to examine whether two natural polyphenols (Padma hepaten (PH) and a polyphenol extraction from green tea (PPFGT)) could inhibit the caries-inducing properties of S. mutans and C. albicans. Methods: Co-species biofilms of S. mutans and C. albicans were grown in the presence of PH and PPFGT. Biofilm formation was tested spectrophotometrically. Exopolysaccharides (EPS) secretion was quantified using confocal scanning laser microscopy. Biofilm development was also tested on orthodontic surfaces (Essix) to assess biofilm inhibition ability on such an orthodontic appliance. Results: PPFGT and PH dose-dependently inhibited biofilm formation without affecting the planktonic growth. We found a significant reduction in biofilm total biomass using 0.625 mg/mL PPFGT and 0.16 mg/mL PH. A concentration of 0.31 mg/mL PPFGT and 0.16 mg/mL PH inhibited the total cell growth by 54% and EPS secretion by 81%. A reduction in biofilm formation and EPS secretion was also observed on orthodontic PVC surfaces. Conclusions: The polyphenolic extractions PPFGT and PH have an inhibitory effect on S. mutans and C. albicans biofilm formation and EPS secretion.

Anxious individuals tend to prefer lingual and clear aligner appliances. The selection of lingual and clear aligner appliances governs the patient's response and recovery process, leaving little room for the effect of psychological features. On the other hand, the buccal appliance allows for greater impact of personality traits on adjustability.

Background Streptococcus mutans (S. mutans) plays a major role in the formation of dental caries. The aim of this study was to examine the effect of the green tea polyphenol, epigallocatechin gallate (EGCG), on biofilm formation of S. mutans. Methods Following exposure to increasing concentrations of EGCG, the planktonic growth was measured by optical density and the biofilm biomass was quantified by crystal violet staining. Exopolysaccharides (EPS) production was visualized by confocal scanning laser microscopy, and the bacterial DNA content was determined by quantitative polymerase chain reaction (qPCR). Gene expression of selected genes was analyzed by real time (RT)-qPCR and membrane potential was examined by flow cytometry. Results We observed that EGCG inhibited in a dose-dependent manner both the planktonic growth and the biofilm formation of S. mutans. Significant reduction of S. mutans biofilm formation, DNA content, and EPS production was observed at 2.2–4.4 mg/ml EGCG. EGCG reduced the expression of gtfB, gtfC and ftf genes involved in EPS production, and the nox and sodA genes involved in the protection against oxidative stress. Moreover, EGCG caused an immediate change in membrane potential. Conclusions EGCG, a natural polyphenol, has a significant inhibitory effect on S. mutans dental biofilm formation and EPS production, and thus might be a potential drug in preventing dental caries.