Bilateral Class Research Articles

Craniofacial characteristics related to daytime sleepiness screened by the paediatric daytime sleepiness scale.

The present cross-sectional study aimed to assess daytime sleepiness in Chinese adolescents using the Paediatric Daytime Sleepiness Scale (PDSS) and to identify associations between PDSS answers and craniofacial characteristics. A group of 265 Chinese adolescents aged 11-17 years self-completed the PDSS, and their extra- and intra-oral craniofacial characteristics were recorded. Among the participants, 59.7% (157) experienced one or more daytime sleepiness events. No significant associations were found between total PDSS scores and the craniofacial parameters, but when PDSS answers were assessed at the item level, several craniofacial characteristics were found to be positively associated with daytime sleepiness, such as hypertrophic tonsils (P = 0.05), a relatively large tongue (P < 0.01), a bilateral Class II molar relationship (P < 0.05) and increased overjet (P < 0.05). A short lower face (P < 0.01) and a convex profile (P < 0.01) were found to be negatively associated with daytime sleepiness. Daytime sleepiness is commonly reported among Chinese adolescents seeking orthodontic treatment and there are potential associations between the condition and craniofacial characteristics. An assessment of daytime sleepiness is recommended to orthodontists in young patients presenting with hypertrophic tonsils, relative large tongues and Class II tendency malocclusions, and appropriate medical referrals should also be considered.

Dentoskeletal Effect Induced by Hyrax Screw Used in Maxillary Molar Distalization: Before–After Study in Class II Patients

2 Background: Maxillary molar distalization with intraoral or extraoral appliances is a common treatment modality in non-extraction treatment plan. Objectives: In this study, an appliance with hyrax screw was used for maxillary molar distalization. Our purpose was to evaluate the amount of molar distalization, type of molar movement, effects on anterior teeth, and amount of changes in lower anterior facial height. Patients and Methods: 24 class II patients (13 females, 11 males) with bilateral half cusp class II molar relationship were participated. The appliance was made by hyrax screw for producing distalization force. Pre and post distalization lateral cephalometric radiographs and dental casts were evaluated. Lateral cephalograms and study models were obtained before treatment and after 12 weeks activation of the appliance (one turn per week). Results: Cephalometric measurement demonstrated that, first molars tipped 2.9 degrees and displaced 1.76 mm. First premolar and upper incisor tipped 3.4 and 4.2 degrees, displaced 2.9 and 2.4 mm respectively. All of these results were statistically significant. The mean of maxillary first molars distaliztion was 2.6 mm per side in approximately four month. The mean of first maxillary molars tip was 3.93˚ and the mean of anchorage loss at the first premolars was 1.95 mm, but the crowns tipped 3.45˚ mesially. Lower anterior facial height (ANS- GN) and mandibular plan angle (GO-GN) increased, 0.7 ± 0.21 mm and 0.76 ± 0.32 degree, respectively, but were statistically insignificant. Conclusions: It can be concluded that proposed appliance can correct class II molar relationship. Molars displaced distally by bodily movement and tipping.

Cephalometric characteristics of Class III malocclusion In Brazilian individuals

Aim: To evaluate the cephalometric characteristics of Class III malocclusion in Caucasian Brazilian subjects. Methods: The sample comprised 71 lateral cephalograms of individuals not previously submitted to any orthodontic treatment. The Class III group (experimental group) comprised 37 patients with bilateral Class III molar relationship and ANB lower than 1 degree, with a mean age of 21.76+3.89 years (13 males and 24 females). The Class I group (control group) consisted of 34 patients with bilateral Class I molar relationship, ANB angle higher than or equal to 1° and lower than 3°, with a mean age of 21.88+3.5 years (12 males and 22 females). Dental, skeletal and soft tissue measurements were compared using the t test for independent samples. Results: The results demonstrated that the Class III individuals showed significant differences in the cephalometric characteristics, except in vertical skeletal variables. The angular variables (SNA, SNB, ANB, SND, 1.1, 1.NA, 1.NB, IMPA, NA.Pog, H.NB) and the linear variables (Pog-Nperp, Co-Gn, 1-orbit, 1-NA, 1-NB, 1-NPog, 1-ANperp, FN-Pog, H-nose, Pog-NB, E menton) demonstrated statistically significant differences between groups. Conclusions: In Class III group, subjects presented maxilla with normal size, yet retruded in relation to the anterior cranial base; protruded mandible with increased size; and concave skeletal and soft tissue profiles. The maxillary incisors were protruded and buccally tipped, and the mandibular incisors were retruded and lingually tipped. Higher prevalence of mandibular prognathism (67.6%) was observed in the Class III group.

A three-dimensional evaluation of Class II subdivision malocclusion correction using Cartesian coordinates

Our objective was to evaluate the reliability of a comprehensive 3-dimensional (3D) evaluation method of dento-skeletal changes using Cartesian coordinates. The coordinates were used to evaluate changes that occurred during non-extraction orthodontic treatment of Class II subdivision malocclusions, and more specifically, describe how the Class II side was corrected to a Class I relation while maintaining the Class I side. The sample consisted of 25 adolescent orthodontic patients diagnosed with a Class II subdivision, and treated non-extraction to a bilateral Class I relation. The pre- (T1) and post-treatment (T2) Cone Beam Computed Tomography scans were oriented using the cranial nerve canals to set the 3 planes of reference, and 19 landmarks were registered on maxillary, mandibular, and dental structures. The data consisted of 3D coordinates representing the distances to the reference planes. A Class I side along with a Class II side was made for each subject. Comparisons were made between sides and between T1 and T2. The data was analyzed using t-test and Pearson׳s Correlation, and the intra-observer reliability was tested by intraclass correlation coefficient. The vertical dimension showed the most variability, both between patients and when comparing T1 versus T2. Treatment effects on the maxillary and mandibular molars on the Class II side were significantly different than the effects seen on the Class I side. There was a weak association between the transverse change, mandibular midline and the antero-posterior change of the mandibular molar on the Class II side. Gonion and PNS showed a tendency for posterior displacement. The coordinate method was found to be reliable for longitudinal studies in 3 dimensions and allows the evaluation of amount and direction of treatment changes. The orthodontic correction of the Class II was due to a combination of refrained forward movement of the maxillary molar and canine, slight outward transverse movement of the maxillary molar, and slight mesial movement of the mandibular molar, all on the Class II side. Our objective was to evaluate the reliability of a comprehensive 3-dimensional (3D) evaluation method of dento-skeletal changes using Cartesian coordinates. The coordinates were used to evaluate changes that occurred during non-extraction orthodontic treatment of Class II subdivision malocclusions, and more specifically, describe how the Class II side was corrected to a Class I relation while maintaining the Class I side. The sample consisted of 25 adolescent orthodontic patients diagnosed with a Class II subdivision, and treated non-extraction to a bilateral Class I relation. The pre- (T1) and post-treatment (T2) Cone Beam Computed Tomography scans were oriented using the cranial nerve canals to set the 3 planes of reference, and 19 landmarks were registered on maxillary, mandibular, and dental structures. The data consisted of 3D coordinates representing the distances to the reference planes. A Class I side along with a Class II side was made for each subject. Comparisons were made between sides and between T1 and T2. The data was analyzed using t-test and Pearson׳s Correlation, and the intra-observer reliability was tested by intraclass correlation coefficient. The vertical dimension showed the most variability, both between patients and when comparing T1 versus T2. Treatment effects on the maxillary and mandibular molars on the Class II side were significantly different than the effects seen on the Class I side. There was a weak association between the transverse change, mandibular midline and the antero-posterior change of the mandibular molar on the Class II side. Gonion and PNS showed a tendency for posterior displacement. The coordinate method was found to be reliable for longitudinal studies in 3 dimensions and allows the evaluation of amount and direction of treatment changes. The orthodontic correction of the Class II was due to a combination of refrained forward movement of the maxillary molar and canine, slight outward transverse movement of the maxillary molar, and slight mesial movement of the mandibular molar, all on the Class II side.

The assessment of sagittal changes with twin block appliance in patients with decelerating growth phase.

The main reason for seeking orthodontic treatment for Class II malocclusions is aesthetic improvement. Growth modification treatment procedures offer better results for a patient with significant potential growth. The aim of this cephalometric clinical study was to distinguish skeletal and dental corrections on skeletal class II division I growing subjects with Twin Block therapy (TB) and the changes were assessed using SO-analysis by Pancherz. Strict diagnostic protocol viz. growing individuals with horizontal growth pattern, skeletal class II due to retrognathic mandible with positive VTO, bilateral class II molar relation, minimal crowding in either arch or overjet more than 5mm was used. Out of 28 selected cases,17 patients received TB therapy and 11 patients were maintained as control group. Standard removable TB appliances with lower incisor capping were delivered to treatment group. The horizontal advancement was about 8mm and 2-3mm vertical opening between the upper and lower central incisors were maintained for all the cases. The mean time interval between the initial (T1)and post treatment (T2) cephalograms of Twin-Block group was 11 month,with a range of 8 month to 13 month. In the control group, the mean time interval between the first (C1)and second (C2) cephalometric films was 12 month,with a range of 10 month to 14 month.T1and T2 cephalograms were traced and S-O analysis was used to segregate dental and skeletal effects. SPSS software was used for statistical analysis. Skeletal Changes: In this study, the mean movement of maxilla was 0.67mm which represents significant restriction of forward maxillary growth in contrast to control groups. Dental Changes: In this study the maxillary molars appear to move distally with a mean value of 0.13mm. Comparing this to the movement of maxillary jaw base itself, maxillary distal movement of molar is less. But still it contributes to Class II correction. The overjet reduction and molar relation correction are more skeletal in nature.

Comparison between an Acrylic Splint Herbst and an Acrylic Splint Miniscrew-Herbst for Mandibular Incisors Proclination Control.

Aim. The aim of this study is to compare dental and skeletal effects produced by an acrylic splint Herbst with and without skeletal anchorage for correction of dental class II malocclusion. Methods. The test group was formed by 14 patients that were treated with an acrylic splint miniscrew-Herbst; miniscrews were placed between mandibular second premolars and first molars; controls also consisted of 14 subjects that were treated with an acrylic splint Herbst and no miniscrews. Cephalometric measurements before and after Herbst treatment were compared. The value of α for significance was set at 0.05. Results. All subjects from both groups were successfully treated to a bilateral Class I relationship; mean treatment time was 8,1 months in the test group and 7.8 in the controls. Several variables did not have a statistical significant difference between the two groups. Some of the variables, instead, presented a significant difference such as incisor flaring, mandibular bone base position, and skeletal discrepancy. Conclusions. This study showed that the Herbst appliance associated to miniscrews allowed a better control of the incisor flaring with a greater mandibular skeletal effect.

Assessment of first molars sagittal and rotational position in Class II, division 1 malocclusion

This study assessed the anterior-posterior positioning of the upper and lower first molars, and the degree of rotation of the upper first molars in individuals with Class II, division 1, malocclusion. Asymmetry I, an accurate device, was used to assess sixty sets of dental casts from 27 females and 33 males, aged between 12 and 21 years old, with bilateral Class II, division 1. The sagittal position of the molars was determined by positioning the casts onto the device, considering the midpalatal suture as a symmetry reference, and then measuring the distance between the mesial marginal ridge of the most distal molar and the mesial marginal ridge of its counterpart. With regard to the degree of rotation of the upper molar, the distance between landmarks on the mesial marginal ridge was measured. Chi-square test with a 5% significance level was used to verify the variation in molars position. Student's t test at 5% significance was used for statistical analysis. A great number of lower molars mesially positioned was registered, and the comparison between the right and left sides also demonstrated a higher number of mesially positioned molars on the right side of both arches. Theaverage rotation of the molars was found to be 0.76 mm and 0.93 mm for the right and left sides, respectively. No statistically significant difference was detected between the mean values of molars mesialization regardless of the side and arch. Molars rotation, measured in millimeters, represented ¼ of Class II.

Total Maxillary Reconstruction Using a Double-Barreled and Double Skin Paddle Fibular Flap after Total Maxillectomy

Chondroblastomas are rare entities accounting for approximately 1% of all primary bone tumors. We describe a case of a 7-year-old girl with a giant chondroblastoma of the maxilla, treated with bilateral class III maxillectomy and reconstruction with a double-barreled and double skin paddle fibular free flap. We show evidence of an excellent aesthetic outcome at 6 months' follow up with no evidence of tumor recurrence.

Effects of mandibular protraction appliance associated to fixed appliance in adults

This retrospective study aimed to conduct a cephalometric evaluation of the skeletal, dental and soft tissue effects resulting from treatment of adult patients presenting Class II malocclusion, performed with a Mandibular Protraction Appliance (MPA) combined with a fixed orthodontic appliance. The sample consisted of teleradiographs obtained before and after treatment of 9 adult patients (initial mean age of 22.48 years) with bilateral Class II, division 1, malocclusion. Paired t test (p < 0.05) was applied to compare initial and final values. t test revealed an increase in anteroinferior facial height and posterior facial height. The dental changes include: extrusion of upper incisors, buccal inclination, protrusion of lower incisors, mesialization and extrusion of mandibular molars. Regarding the soft tissue component, there was an increase in nasolabial angle in addition to upper lip retrusion. The effects of treating Class II malocclusion adult patients, by means of using Mandibular Protraction Appliance (MPA) combined with a fixed appliance were mostly observed in the mandibular arch, and consisted of buccal inclination, protrusion and intrusion of incisors, and mesialization and extrusion of the molars.

A clinical evaluation of a bioresorbable membrane and porous hydroxyapatite in the treatment of human molar class II furcations

Background:The ultimate goal of periodontal therapy is predictable regeneration of a functional attachment apparatus destroyed as a result of periodontitis. Reconstructive procedures have been used with varying success during the past decades to accomplish this goal.Aim:To evaluate whether the use of porous hydroxyapatite alone or a bioresorbable membrane alone would enhance the clinical results in the treatment of class II furcation defects in human lower molars.Materials and Methods:Fifteen patients with chronic periodontitis, aged between 39 and 49 years, with a pair of similar bilateral class II furcation defects (classification of Hamp et al.) in mandibular first molars were selected. A split-mouth design was incorporated and the selected 30 furcation defects were assigned to one of the two treatment groups, i.e., Group I treated with a bioresorbable membrane from bovine-derived collagen guided tissue regeneration membrane and Group II treated using porous hydroxyapatite bone graft material on the contralateral sides. Evaluation of clinical parameters, probing depths and attachment levels, and radiographs was done preoperatively and 6 months postoperatively.Results:Both the groups showed statistically significant mean reduction in probing depths and gain in clinical attachment levels and linear bone fill. Comparison between Group I and Group II showed insignificant difference.Conclusion:Within the limits of this study, both the treatment modalities are beneficial for the treatment of human mandibular class II furcation defects.

Prevalence of malocclusion in urban libyan preschool children.

Objectives:This cross-sectional observational study aimed at quantifying primary dentition parameters and exploring differences in those parameters between included age groups.Materials and Methods:The examined sample comprised 800 preschool children, 3- to 5-year-old in Benghazi city, of which 500 fulfilled the inclusion criteria. Primary canine relationship, spacing/crowding, overjet (OJ) and overbite (OB), occlusal relationship was carried out using Federation Dentaire Internationale (1973), modified to the primary dentition.Results:The prevalence of bilateral Class I, Class II, and Class III canine relationship was 69.6%, 22.4%, and 4.4%, respectively. The prevalence of asymmetric canine relationship was 3.6% with no significant difference between gender and age groups. Spacing, closed dentition, and crowding were observed in: 81.6%, 13,4% and 5% respectively in the upper arch, and 58.5%, 24.8%, and 16.7% correspondently in the lower arch. OJ and OB ranging between 1 and 3 mm were found in 82.6% and 56.5%, respectively. An OJ and OB of >3 mm was observed in 11.4% and 35%, respectively, and of edge to edge incisal relationship anteroposteriorly and vertically in 4.6% and 6% in this order. Anterior crossbite and anterior openbite were noted in 1.4% and 2.6%, respectively. There was no significant correlation between OJ and OB and age (P≥0.241). Additionally, there was no significant sex difference in the value of OJ (P=0.561). But, the mean OB value in boys was significantly greater than in girls.Conclusions:The current findings provide an insight into the prevalence of occlusal traits in urban Libyan preschool children and highlight the significance of early detection of malocclusion to assist in achieving effective and individualized long-term treatment planning.

Class II subdivision treatment with the Herbst appliance

To assess the effectiveness of Class II subdivision Herbst nonextraction treatment and its short-term stability retrospectively. Twenty-two Class II subdivision (SUB: right-left molar difference ≥0.75 cusp width) and 22 symmetric Class II patients (SYM: ≥0.75 cusp width bilaterally) were matched according to gender and pretreatment handwrist radiographic stage. The mean treatment duration of the Herbst and subsequent multibracket phase was 8 months and 14 months, respectively. The mean retention period amounted to 36 months. Dental casts from before treatment (T1), after Herbst treatment (T2), after Multibracket treatment (T3), and after retention (T4) were evaluated. A bilateral Class I or super Class I molar relationship was seen in 72.7% (SUB) and 77.3% (SYM) at T3. The corresponding values at T4 were 63.7% (SUB) and 72.7% (SYM). A unilateral or bilateral Class III molar relationship was more frequent in the SUB group (T3: +4.6%; T4: +13.6%). For overjet, similar mean values were seen in both groups after treatment (T3: SUB, 2.7 mm; SYM, 2.3 mm) and after retention (T4: SUB, 3.0 mm; SYM, 3.4 mm). This was also true for the midline shift (T3: SUB, -0.4 mm; SYM, 0.0 mm; T4: SUB, -0.3 mm; SYM, 0.0 mm). Class II subdivision Herbst treatment was successful similarly to symmetric Class II Herbst treatment. However, a slight overcompensation of the molar relationship (Class III tendency) was more frequent in the subdivision patients (original Class I side).

Platelet-rich plasma in the treatment of Class II furcation defects: a histometrical study in dogs

Objective This study was designed to evaluate the potential adjunctive benefits of platelet-rich plasma (PRP) when used with guided-tissue regeneration (GTR) and bioactive glass (BG) in the treatment of Class II furcation lesions. Material and Methods Bilateral Class II furcation lesions were surgically created and allowed to become chronic in the mandibular third premolars of 9 dogs. The defects were randomly assigned to: A) GTR+BG and B) GTR+BG+PRP. Similar defects were created in the maxillary third premolars and received the same treatments after 45 days. Dogs were sacrificed 90 days after the first treatment. The histometric parameters evaluated were: connective tissue adaptation, new cementum, new bone, mineralized bone area, non-mineralized bone area, and residual BG particle area. Results Data analysis showed a superior length of new cementum and a greater mineralized bone area for group B in both periods (p<0.05). The non-mineralized bone area was greater in the control group (p<0.05) in both periods. Conclusion Within the limits of this study, it can be concluded that the use of PRP in the treatment of Class II furcation defects may enhance the amount of new cementum and provide a more mineralized bone in a shorter period of time.

Orthodontic and surgical treatment of a patient with hemifacial microsomia

This article describes the surgical and orthodontic treatment of a 12-year-old boy with a significant deformity and functional involvement caused by hemifacial microsomia. The left mandibular ramus and condyle were hypoplastic and abnormal in form and location. The lower third of the face was increased, with mandibular retrusion and significant facial asymmetry. He had difficulties in speaking and chewing and problems related to his facial appearance, which caused severe psychosocial disturbances. The patient received orthodontic treatment and temporomandibular joint reconstruction with a costochondral graft on the left side while he was still growing. Three-year follow-up records are presented.

Autologous periodontal ligament cells in the treatment of class III furcation defects: a study in dogs

This study aimed to evaluate, histomorphometrically, the use of periodontal ligament cells (PDL cells) in the treatment of class III furcation defects. PDL cells were obtained from the mandibular tooth extracted from each dog (7), cultured in vitro and phenotypically characterized. Bilateral class III furcation defects were created at mandibular 3rd and 4th premolars and were randomly assigned to: coronally positioned flap, GTR Group: GTR, Sponge Group: carrier + GTR, Cell Group: carrier + PDL cells + GTR. After 3months of healing, data analysis demonstrated that the Cell Group presented a superior length of new cementum (4.82±0.61mm; 3.66±0.95mm; 2.87±0.74mm and 1.70±0.60mm, p<0.001), a greater extension of periodontal regeneration (3.43±1.44mm; 2.33±0.95mm; 1.52±0.39mm and 0.69±0.59mm, p=0.001) and a larger area of new bone (5.45±1.58mm(2) ; 3.94±1.52mm(2) ; 2.91±0.56mm(2) and 1.89±0.95mm(2) , p=0.0012), when compared with Sponge, GTR and CONTROL GROUP, respectively. The PDL cells in association with GTR may significantly promote periodontal regeneration in class III furcation defects surgically created in dogs.

Comparative Evaluation of Guided Tissue Regeneration with use of Collagen-based Barrier Freeze-Dried Dura Mater Allograft for Mandibular Class 2 Furcation Defects (A Comparative Controlled Clinical Study)

The aim of periodontal surgery is complete regeneration. The present study was designed to evaluate and compare clinically soft tissue changes in form of probing pocket depth, gingival shrinkage, attachment level and hard tissue changes in form of horizontal and vertical bone level using resorbable membranes. Twelve subjects with bilateral class 2 furcation defects were selected. After initial phase one treatment, open debridement was performed in control site while freezedried dura mater allograft was used in experimental site. Soft and hard tissue parameters were registered intrasurgically. Nine months reentry ensured better understanding and evaluation of the final outcome of the study. Guided tissue regeneration is a predictable treatment modality for class 2 furcation defect. There was statistically significant reduction in pocket depth as compared to control (p < 0.01). There is statistically significant increase in periodontal attachment level within control and experimental sites showed better results (p < 0.01). For hard tissue parameter, significant defect fill resulted in experimental group, while in control group, less significant defect fill was found in horizontal direction and nonsignificant defect fill was found in vertical direction. The results showed statistically significant improvement in soft and hard tissue parameters and less gingival shrinkage in experimental sites compared to control site. The use of FDDMA in furcation defects helps us to achieve predictable results. This cross-linked collagen membrane has better handling properties and ease of procurement as well as economic viability making it a logical material to be used in regenerative surgeries.

Treatment of bilateral furcation involvements with bonegraft and bioabsorbable barriers

AbstractBilateral furcation involvements are a common occurrence. This case demonstrates the surgical treatment of bilateral furcation involvement at a single appointment. This article presents successful management of bilateral class II furcation involvement affecting lower molars with particulate bonegraft (betaTCP + HA) and guided tissue generation(GTR) bioabsorbable membrane. This article reiterates the fact that class II furcations are ideal cases for therapy bone graft +GTR and respond favorably to this therapy. Further treatment at a single appointment is more convenient and time saving for both the patient and the operator when the patient is deemed compliant to follow post operative instructions.

The form of upper Dental arch for Mosuli Adults (Acomputerized study)

Aims: To find out the most frequent dental arch form in Mosuli adults. Establishment of the normative values of the upper dental arch dimensions. Materials and Methods: The sample of this study involved students from Mosul University, 95 students (58 females, 37 males) were selected. The age of the sample ranged between 18–25 years old. They were normal healthy individuals of Mosul origin. Full complement of permanent dentition, bilateral Class I molar and canine occlusion. The data recorded in this research were subjected to computerized statistical analysis using SPSS programs, including descriptive statistics (mean, standard deviation, minimum, maximum), Student’s t–test was applied to test the significant differences between the genders. Results: There were highly significant differences between males and females of the vertical measurements, that males had larger arch length than females. Also, males had larger arch width with a highly significant difference at p < 0.01 in all width dimensions in maxillary arches. It could be noticed that the most prevalent arch form among the sample was the Mid form followed by the Narrow and Wide then flat & pointed forms. Conclusions: The mid arch form is the most frequent arch form followed by other types. All the measured dimensions (width and length) have significantly greater mean value in males than in females with significant difference for linear measurements. no significant difference in ratio between genders.

Autologous periodontal ligament cells in the treatment of class II furcation defects: a study in dogs

The goal of this study was to histologically investigate the use of periodontal ligament cells (PDL cells) in tissue engineering to regenerate class II furcation defects. PDL cells were obtained from the mandibular tooth extracted from each dog (seven), cultured in vitro and phenotypically characterized with regard to their biological properties. Following, bilateral class II furcation lesions were created at maxillary 3rd premolars and were randomly assigned to the test group [PDL cells+guided tissue regeneration (GTR)] or the control group (GTR). After 3 months, the animals were euthanized to evaluate the histometric parameters. In vitro, PDL cells were able to promote mineral nodule formation and to express bone sialoprotein, type I collagen and alkaline phosphatase. Histometrically, data analysis demonstrated that the cell-treated group presented a superior length of new cementum (6.00 ± 1.50 and 8.08 ± 1.08 mm), a greater extension of periodontal regeneration (3.94 ± 1.20 and 7.28 ± 1.00 mm), a lower formation of connective tissue/epithelium (2.15 ± 1.92 and 0.60 ± 0.99 mm), a larger area of new bone (7.01 ± 0.61 and 9.02 ± 2.30 mm(2)) and a smaller area of connective tissue/epithelium (5.90 ± 1.67 and 4.22 ± 0.95 mm(2)), when compared with control group. PDL cells in association with GTR may significantly promote periodontal regeneration in class II furcation defects in dog.

Effetti dentoscheletrici di un dispositivo intraorale per la distalizzazione dei molari e confronto sistematico con apparecchi alternativi

Objective The aim of the present study was to evaluate the dentoskeletal effects produced by an intraoral appliance for the unilateral or bilateral distalization of the upper first molars. Materials and methods We analyzed the pre- and post-distalization cephalometric films of 17 patients (10 males and 7 females) with class II malocclusion treated with the First Class appliance. The mean age at the start of treatment was 13 years and 4 months. Bilateral class II molar relationships were corrected within 2.4 months on average. Results Seventy percent of the space created anterior to the first molars was the result of maxillary molar distalization; the remaining 30% was due to reciprocal loss of anchorage by the maxillary second premolars. The maxillary first molars showed significant distalization of 4.0 mm, associated with a significant distal inclination of 4.6 degrees and a significant extrusion of 1.2 mm. As for loss of anchorage, the second premolars exhibited significant mesial movement of 1.7 mm and significant mesial inclination of 2.2 degrees. In the anterior region, significant mesial movement of the maxillary incisors of 1.3 mm was associated with significant incisor proclination (2.6 degrees) and a significant increase in the overjet (1.2 mm). No significant changes in either sagittal or vertical skeletal relationships were observed. Conclusions The results suggest that the intraoral appliance can produce efficient distalization of the maxillary permanent first molars comparable to that offered by other intraoral distalization devices.