Giuseppina Laganà

Prevalence of malocclusions, oral habits and orthodontic treatment need in a 7- to 15-year-old schoolchildren population in Tirana

BackgroundThe aim of present study was to determine the prevalence of malocclusions, oral habits and the need for orthodontic treatment in a sample of 7- to 15-year-old Albanese schoolchildren.MethodsThe final sample comprised 2,617 subjects (1,257 males and 1,360 females), all orthodontically untreated. Occlusal relationship and the functional analysis were recorded for all subjects. The prevalence rates for the dental health component of the index of orthodontic treatment need (IOTN) were calculated. Comparisons between genders were performed for the prevalence of malocclusions, oral habits and IOTN grades (chi-square tests).ResultsClass I, class II and class III malocclusions and asymmetries were observed in 40.4%, 29.2%, 3.2% and 27.1% of the sample, respectively. There were 2,108 subjects (80.6%) that showed oral habits, with females (82.1%) presenting with a greater prevalence rate than males (78.9%). The objective need for orthodontic treatment (grades 4 and 5 of IOTN) was registered in 1,077 subjects (41.2%). This prevalence rate is higher than those reported for other European countries. No significant differences between genders were found for the IOTN grades.ConclusionsThe findings of the present study revealed the need to improve public health plans for orthodontic prevention and screening and to organise the resources in this area in Albania.

Three-dimensional densitometric analysis of maxillary sutural changes induced by rapid maxillary expansion

OBJECTIVE This prospective study evaluated the density of the midpalatal and transverse sutures as assessed by low-dose CT before rapid maxillary expansion (T0), at the end of active expansion (T1) and after a retention period of 6 months (T2). METHODS The study sample comprised 17 pre-pubertal subjects (mean age 11.2 years) with constricted maxillary arches. Total amount of expansion was 7 mm in all subjects. Multislice low-dose CT scans were taken at T0, T1 and T2. On the axial CT scanned images six regions of interest (ROIs) were placed along the midpalatal and transverse sutures and two in maxillary and palatal bony areas. Density was measured in Hounsfield units. Mann-Whitney U test and Friedman analysis of variance with post hoc tests were used (p < 0.05). RESULTS The three ROIs in the midpalatal suture showed a significant decrease in density from T0 to T1, a significant increase from T1 to T2 and a lack of statistically significant differences from T0 to T2. Both ROIs located in the transverse suture showed a significant decrease in density from T0 to T1, followed by a non-significant increase in density from T1 to T2. CONCLUSIONS At the end of the active phase of expansion a significant reduction in density along the midpalatal and transverse sutures was observed in all subjects. The sutural density of the midpalatal suture at T2 indicated reorganization of the midpalatal suture while the density along the transverse suture increased without reaching the pre-treatment values, possibly due to different morphology between midpalatal and transverse sutures.

Compositional studies of functional orthodontic archwires using prompt-gamma activation analysis at a pulsed neutron source

Prompt-gamma activation analysis (PGAA) measurements were carried out at the ISIS Spallation Neutron Source on two sets of functional commercial stainless steel orthodontic archwires, aiming at providing insights into the elemental and isotopic composition differences of two nominally equivalent archwires. The results were compared to those obtained from parallel cold neutron PGAA measurements on the same samples at the Budapest Neutron Centre in order to test the current status of PGAA at a pulsed neutron source and eventually to inform improvement in set-up and acquisition methods. In addition, time-resolved PGAA (T-PGAA) that combines PGAA and neutron time-of-flight methods was applied to the present set of samples, allowing the measurement of the neutron energy dependence of the PGAA spectra. The advantages of this technique were demonstrated to be that through incident neutron energy selection, spanning 0.07–67.94 eV, enhancement or decrease of specific gamma lines associated with isotopes of interest could be achieved. These were shown to reduce peak interference and to increase the signal-to-background ratio for certain species in order to facilitate accurate elemental identification. Suggestions for potential performance improvement for this evolving technique are proposed.

Orthodontic archwire composition and phase analyses by neutron spectroscopy

Quantitative metallurgical and phase analyses employing neutron diffraction technique were conducted on two as-received commercial rectangular austenitic stainless steel orthodontic archwires, G&H and Azdent, 0.43×0.64 mm (0.017×0.025 inch). Results showed a bi-phase structure containing martensitic phase (45.67% for G&H and 6.62% for Azdent) in addition to the expected metastable austenite. The former may be a strain-induced phase-transformation arising during the cold working process of wire fabrication. Further neutron resonance capture analysis determinations provided atomic and isotopic compositions, including alloying elements in each sample, complementary to the results of traditional energy dispersive X-ray spectroscopy. Together, these results assist in relating commercial alloying recipes and processing histories with mechanical performance, strength and ductility in particular.

Geometric morphometric analysis of the palatal morphology in children with impacted incisors: A three-dimensional evaluation

OBJECTIVE To analyze variations in palatal morphology in subjects presenting unilaterally impacted maxillary permanent central incisors compared with a control group of subjects without eruption anomalies using a three-dimensional (3D) analysis. MATERIALS AND METHODS Twenty-six white subjects (10 girls and 16 boys; mean age 9.5 ± 1.5 years) with unilaterally impacted maxillary permanent central incisors (impacted incisor group [IIG]) were compared with a control group (CG) of 26 subjects (14 girls and 12 boys, mean age 8.7 ± 1.6 years) presenting no eruption disorders. For each subject, dental casts were taken and the upper arch was scanned using a 3D laser scanner. To study the entirety of the shape of the palate in any point of the surface, 3D geometric morphometrics was applied. RESULTS Subjects with impacted maxillary incisors showed skeletal adaptations of the maxilla. In the IIG, both the superior palatal region and lateral palatal surface showed significantly different morphology when compared with CG, with a narrower and higher palatal vault. CONCLUSION The absence of maxillary central incisors over the physiological age of eruption influenced the development of the palatal morphology compared with subjects without eruption anomalies.

Obstructive sleep apnea in children with Marfan syndrome: Relationships between three-dimensional palatal morphology and apnea-hypopnea index

OBJECTIVE To evaluate the relationship between the severity degree of OSA (apnea/hypopnea index AHI>1) and palatal area and volume, measured by 3D analysis of digital casts in Marfan children. METHODS Twenty children with a clinical diagnosis of MS were recruited from a tertiary medical center. All the subjects underwent standard nocturnal polygraphy testing. Sixteen Marfan patients (7F,9 M; mean age 8.8yy ± 1.5yy) with AHI>1 were enrolled. Marfan Group (MG) was compared with a control group (CG) of 17 children without Marfan syndrome (9F,8 M; mean age 8.5yy ± 1.7yy) presenting with nose-breathing pattern. For each subject maxillary digital casts were taken and palatal area and volume were measured. Unpaired t-test was used to test significant differences between MG and CG for area and volume measurements. Pearson correlation coefficient (PCC) was used to measure the linear correlation between the degree of OSA (AHI index) and palatal volume and palatal area. RESULTS 80% of Marfan children presented an AHI>1 and a diagnosis of OSA. MG presented statistically significant lower values of palatal surface area (662.68 mm2; P < 0.0001) and palatal volume (2578.1 mm3; P < 0.0001) with respect to CG (923.0 mm2 and 3756.6 mm3, respectively). Correlation analysis showed that AHI index had no linear correlation with palatal area (r = - 0,07) and with palatal volume (r = - 0,11). CONCLUSION OSA is highly prevalent in children with Marfans syndrome (80%). Marfan children present a reduction of palatal area and volume when compared to healthy subjects. OSA in Marfan children is not linear correlated to the palatal morphology and it shows a multifactorial aetiology.

Geometric morphometric analysis of the palatal morphology in growing subjects with skeletal open bite

OBJECTIVES To assess the morphological shape variations of the palatal vault in Open Bite (OB) growing subjects when compared with a Control Group (CG) by means of Geometric Morphometric Method (GMM). MATERIALS AND METHODS The OB Group (OBG) consisted of 75 subjects (39 females, 36 males; mean age: 8.5 ± 0.8 years) who were collected retrospectively with the following inclusion criteria: European ancestry, overbite less than 0 mm, mixed dentition stage, prepubertal skeletal maturation (CS1-CS2), hyperdivergent skeletal pattern (SN^GoGn > 37°). The OBG was compared with a CG of 46 prepubertal subjects presenting normal occlusion (24 females, 22 males; mean age of 8.3 ± 1.7 years). For each subject, lateral cephalograms and maxillary dental casts were available. Landmarks and semilandmarks were digitized on digital dental casts and GMM was applied. Procrustes analysis and principal component analysis (PCA) were performed. OBG was divided in two subgroups: Sucking Habits Group (SHG) (39 subjects) and Non-Sucking Habits Group (NSHG) (36 subjects). RESULTS PC1 showed significant morphological changes in transverse and vertical dimensions with OBG palates higher and narrower when compared with CG. When comparing the two subgroups no statistically significant differences were found. NSHG demonstrated a slight reduction of the transverse dimension and a deeper palatal vault respect to SHG. LIMITATIONS The limitations of this study were the division of OBG in two subgroups based on referral of thumb sucking habits without assessing the duration and the intensity of thumb sucking. CONCLUSIONS OB subjects presented with a significant constriction of the maxillary arch when compared with CG. The morphological palatal shape variations in OBG were not influenced by the presence or absence of non-nutritive sucking habits.

Mechanical properties of “two generations” of teeth aligners: Change analysis during oral permanence

Aim of this in vitro study was to analyze structural properties of two different polymeric orthodontic aligners, Exceed30 (EX30) and Smart Track (LD30), before and after use. Forty patterns of aligners were randomly selected: 20 LD30 and 20 EX30, worn intra-orally for 14±3 days, 22 h/day. From each aligner, 10 specimens were prepared from buccal surfaces of the incisor region by the cutting of samples 5×5 mm under a stereomicroscope. All samples were subjected to Fourier transform infrared spectroscopy, micro-Raman spectroscopy, X-ray diffraction, tensile and indentation strength test. LD30 appeared more homogeneous, with a crystalline fraction lower than EX30 and exhibited a higher elastic behavior and a lower tendency to warp after use than EX30. LD30 demonstrated better adaptability to the dental arch and greater consistency of application of orthodontic forces than produced with EX30. However, both materials showed structural modifications that resulted in increased sample hardness and hyper-plasticity.

Omega-3 and Omega-6 Fatty Acids Act as Inhibitors of the Matrix Metalloproteinase-2 and Matrix Metalloproteinase-9 Activity

Polyunsaturated fatty acids have been reported to play a protective role in a wide range of diseases characterized by an increased metalloproteinases (MMPs) activity. The recent finding that omega-3 and omega-6 fatty acids exert an anti-inflammatory effect in periodontal diseases has stimulated the present study, designed to determine whether such properties derive from a direct inhibitory action of these compounds on the activity of MMPs. To this issue, we investigated the effect exerted by omega-3 and omega-6 fatty acids on the activity of MMP-2 and MMP-9, two enzymes that actively participate to the destruction of the organic matrix of dentin following demineralization operated by bacteria acids. Data obtained (both in vitro and on ex-vivo teeth) reveal that omega-3 and omega-6 fatty acids inhibit the proteolytic activity of MMP-2 and MMP-9, two enzymes present in dentin. This observation is of interest since it assigns to these compounds a key role as MMPs inhibitors, and stimulates further study to better define their therapeutic potentialities in carious decay.

Effects of cervical headgear and pendulum appliance on vertical dimension in growing subjects: a retrospective controlled clinical trial

OBJECTIVE To analyze the effects on vertical dentoskeletal dimension produced by cervical headgear (CHG) or Pendulum (P) both followed by full fixed appliances in growing patients with Class II malocclusion. MATERIAL AND METHODS The CHG group (CHGG) consisted of 40 patients (25 females, 15 males) with a mean age of 11.5 years. The P group (PG) comprised 40 patients (21 females, 19 males) with a mean age of 11.6 years. Mean treatment duration with the CHG and P appliances were 1.5 years and 8.2 months, respectively. Lateral cephalograms were available before treatment (T1) and at the end of fixed therapy (T2) with a mean interval of 3.5 years. The effects of the 2 protocols were compared with a matched control group (CG) of 25 untreated Class II subjects (13 females, 12 males). The ANOVA with Tukeys post hoc tests was used to evaluate between-group differences at T1 and during the T1-T2 interval (P < 0.05). RESULTS CHGG showed significantly greater decreases in both Sella-Nasion to A point angle and A-Nasion-B point anglel when compared with both PG (-1.2 and -0.9 degrees, respectively) and CG (-1.9 and -1.5 degrees, respectively). No significant between-group differences were recorded for any of the vertical skeletal measurements. Both CHGG and PG showed significantly greater improvement in molar relationships with respect to CG (+2.5mm). CONCLUSIONS Both distalizing protocols were effective in the correction of Class II malocclusion without increasing the vertical dimension at the end of comprehensive treatment.