Susana Maria Deon Rizzatto

Immediate effects of rapid maxillary expansion with Haas-type and hyrax-type expanders: A randomized clinical trial

INTRODUCTIONnThe purposes of this study were to evaluate and compare the immediate effects of rapid maxillary expansion (RME) in the transverse plane with Haas-type and hyrax-type expanders by using cone-beam computed tomography.nnnMETHODSnA sample of 33 subjects (mean age, 10.7 years; range, 7.2-14.5 years) with transverse maxillary deficiency were randomly divided into 2 groups: Haas (nxa0= 18) and hyrax (nxa0= 15). All patients had RME with an initial activation of 4 quarter turns followed by 2 quarter turns per day until the expansion reached 8 mm. Cone-beam computed tomography scans were taken before expansion and at the end of the RME phase. Maxillary transversal measurements were compared by using the mixed analysis of variance (ANOVA) model and the Tukey-Kramer method.nnnRESULTSnRME increased all maxillary transverse dimensions (Pxa0<0.0001). There was less expansion at skeletal than dental levels. The hyrax group had greater statistically significant orthopedic effects and less tipping tendency of the maxillary first molars compared with the Haas group.nnnCONCLUSIONSnBoth appliances were efficient in correcting a transverse maxillary deficiency. The pure skeletal expansion was greater than actual dental expansion. The hyrax-type expander produced greater orthopedic effects than did the Haas-type expander, but this effect was less than 0.5 mm per side and might not be clinically significant.

Dentoskeletal effects of maxillary protraction in cleft patients with repetitive weekly protocol of alternate rapid maxillary expansions and constrictions.

Objective: To evaluate the amount of maxillary protraction with face mask in complete unilateral cleft lip and palate patients submitted to two distinct rapid maxillary expansion (RME) protocols. Material and Methods: The sample consisted of 20 individuals (nine boys and 11 girls; mean age of 10.4 ± 2.62 years) with unilateral complete cleft lip and palate who had a constricted maxilla in the vertical and transverse dimensions. Ten patients underwent 1 week of RME with screw activation of one complete turn per day, followed by 23 weeks of maxillary protraction (group 1). The other 10 patients underwent 7 weeks of alternate rapid maxillary expansion and constriction, with one complete turn per day, followed by 17 weeks of maxillary protraction (group 2); both groups underwent a total of 6 months of treatment. Cephalometric measurements were taken at different times: pretreatment (T1), soon after RME (T2), and after 6 months of treatment (T3). Each measurement was analyzed with mixed models for repeated measures, and the covariance structure chosen was compound symmetry. Results: The maxilla displaced slightly forward and downward with a counterclockwise rotation; the mandible rotated downward and backward, resulting in an increase in anterior facial height; the sagittal maxillomandibular relationship was improved; the maxillary molars and incisors were protruded and extruded; and the mandibular incisors were retroclined. Conclusion: There was no significant difference between the groups in evaluation time.

Gingival margin alterations and the pre-orthodontic treatment amount of keratinized gingiva

The purpose of this retrospective study was to associate the amount of keratinized gingiva present in adolescents prior to orthodontic treatment to the development of gingival recessions after the end of treatment. The sample consisted of the intra-oral photographs and orthodontic study models from 209 Caucasian patients with a mean age of 11.20 +/- 1.83 years on their initial records and 14.7 +/- 1.8 years on their final records. Patients were either Angle Class I or II and were submitted to non-extraction orthodontic treatment. Gingival recession was evaluated by visual inspection of the lower incisors and canines as seen in the initial and final study models and intra-oral photographs. The amount of recession was quantified using a digital caliper and the observed post-treatment gingival margin alterations were classified as unaltered, coronal migration of the gingival margin or apical migration of the gingival margin. The width of the keratinized gingiva was measured from the mucogingival line to the gingival margin on the pre-treatment photographs. The teeth that developed gingival recession and those that did not have their gingival margin position changed did not differ in relation to the initial amount of keratinized gingiva (3.00 +/- 0.61 and 3.5 +/- 0.86 mm, respectively). Paradoxically, teeth that presented a coronal migration of the gingival margin had a smaller initial amount of keratinized gingiva (2.26 +/- 0.31 mm). The mean amount of initial keratinized gingiva did not predispose lower incisors and canines to gingival recession.

Characteristics and distribution of dental anomalies in a Brazilian cleft population

OBJETIVOS: Determinar a prevalencia de anomalias dentarias em 200 pacientes com fissura sob tratamento ortodontico no Centro de Reabilitacao Labio-Palatal (CERLAP) da Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS). METODOLOGIA: Os dados referentes a idade, raca, genero, tipo de fissura (pre, trans ou pos-forame incisivo), lado afetado (uni ou bilateral), agenesias e supranumerarios em ambas arcadas foram avaliados a partir da documentacao ortodontica constituida por radiografias panorâmicas, cefalometricas, oclusais e periapicais, modelos de estudo e fotografias intra e extrabucais obtidas no inicio do tratamento, fornecendo informacoes necessarias para diagnostico de anomalias dentarias. Os dados coletados foram registrados em planilhas. RESULTADOS: A media de idade dos pacientes foi de 13.5 anos; 86% eram brancos; e 57% eram meninos. Fissuras transforame incisivo demonstraram-se mais frequentes (83%); o lado esquerdo foi mais afetado (48.5%). Agenesias foram encontradas em 66.5% dos pacientes. Incisivos laterais superiores foram os dentes mais ausentes (78.5%). Supranumerarios foram encontrados em 35.5 % dos pacientes. CONCLUSAO: Meninos demonstraram maior tendencia a apresentar fissuras e a manifestar agenesias dentarias e supranumerarios. As fissuras completas de labio e palato prevaleceram e os incisivos laterais superiores foram os dentes mais ausentes. Os supranumerarios localizaram-se distalmente a fissura na maioria dos casos.

Sagittal changes in lower incisors by the use of lingual arch

OBJECTIVEnThe objective of this study was to evaluate a sagittal variation on the lower incisors with the use of the lingual arch on the transition from mixed to permanent dentition.nnnMETHODSnThe sample was constituted of 44 Caucasian patients (26 girls and 18 boys), divided in two groups: CG, control group, monitoring the lower arch space with no orthodontic/orthopedic treatment during the rated period (n = 14); EG, experimental group, presenting anterior inferior mild crowding and installation of the lingual arch for space maintenance (n = 30). The position of the lower incisors was analyzed on computerized cephalometric tracings performed at the beginning of the monitoring (T1) and at the end, on the permanent dentition (T2). In order to evaluate the position of the incisors it was used Tweed and Steiner measurements: IMPA, 1.NB and 1-NB. The alterations were analyzed through the t test for paired samples, while the differences between the groups were analyzed through the t test for independent samples, as for sexual dimorphism.nnnRESULTSnThe values in T2 were greater in relation to T1 for all measurements on EG (IMPA, p = 0.038; 1.NB, p = 0.007 and 1-NB, p < 0.0001). On comparing the differences (T2-T1) between CG and EG, it can be gauged differences significantly superior for measure 1.NB (p = 0.002) and 1-NB (p < 0.0001) on EG. There was no statistically significant difference between genres.nnnCONCLUSIONSnIt was concluded that the lower incisors were projected after using the lingual arch to control the space on the transition from mixed to permanent dentition, however, within acceptable standards, not having difference between genres.

Orthodontically induced eruption of a horizontally impacted maxillary central incisor

This case report presents the clinical features and periodontal findings in a patient with a horizontally impacted maxillary central incisor that had been exposed and aligned after a closed-eruption surgical technique. By combining 3 treatment stages-maxillary expansion, crown exposure surgery, and induced eruption-the horizontally impacted incisor was successfully moved into proper position. The patient finished treatment with a normal and stable occlusion between the maxillary and mandibular arches, and an adequate width of attached gingiva, even in the area surrounding the crown. The 5-year follow-up of stability and periodontal health demonstrated esthetic and functional outcomes after orthodontically induced tooth eruption. Clinical evaluation showed that the treated central incisor had periodontal clinical variables related to visible plaque, bleeding on probing, width of attached gingiva, and crown length that resembled the contralateral incisor.

Orthodontic-restorative treatment as an option for biologic replacement of a maxillary central incisor: 5-year follow-up

The maxillary central incisor is the tooth most often affected by trauma, especially in the age range of 7 to 10 years, when high-impact sports are prevalent. The options for conservative treatment should be prioritized in these patients, aiming to achieve a biologic response that might provide continuity of growth of the alveolus, to provide functional and esthetic development of the affected region. This case report describes a patient with a history of trauma during the deciduous dentition with consequent intrusion, root dilaceration, and retention of the maxillary left central incisor. The treatment involved extraction of the traumatized tooth and mesial movement of the lateral incisor and posterior segments.

Análises microbiológicas de alicates ortodônticos

AbstractObjective: To evaluate bacterial contamination in the active tip of orthodontic pliers used in an academic setting. Methods: Thirty-four pliers were selected: 17 debonding pliers and 17 model 139 pliers. The control group was composed of 3 previously autoclaved pliers of each model. After use, the pliers in the experimental group were immersed in 10 ml of brain-heart infusion (BHI) culture medium for 2 minutes, incubated at 37o C for 24 to 48 h and seeded in duplicates in different agar-based solid culture media to detect and identify microbial agents. Results: Microbiological analyses revealed that there was contamination in both types of orthodontic pliers. Several bacteria were detected, predominantly staphylococcus and isolated Gram-positive (G+) cocci. The debonding pliers had a greater contamination rate and mean values of 2.83 x 10 9 and 6.25 x 10 CFU/ml, with variations according to the type of culture medium. The 139 pliers also had all types of bacteria from the oral microbiota at values that ranged from 1.33 x 10

Cone-Beam computed tomography evaluation of maxillary expansion in twins with cleft lip and palate

OBJECTIVE: The establishment of normal occlusal relationships in patients with cleft lip and palate using rapid maxillary expansion may promote good conditions for future rehabilitation. OBJECTIVE: This study describes the clinical case of monozygotic twins with unilateral cleft lip and palate at the age of mixed dentition, who were treated using the same rapid maxillary expansion protocol, but with two different screws (conventional and fan-type expansion screw). Results were evaluated using plaster models, intraoral and extraoral photographs, and Cone-Beam computed tomography (CBCT) scans obtained before the beginning of the treatment, (T1). METHODS: The patients were followed up for 6 months after maxillary expansion, when the same tests requested at T1 were obtained again for review (T2). T1 and T2 results were compared using lateral cephalometric tracings and measurements of the intercanine and intermolar distances in the plaster models using a digital caliper. RESULTS: The two types of expansion screws corrected the transverse discrepancy in patients with cleft lip and palate. The shape of the upper arches improved at 10 days after activation. CONCLUSION: CBCT scans provide detailed information about craniofacial, maxillary and mandibular changes resulting from rapid maxillary expansion. The most adequate screw for each type of malocclusion should be chosen after detailed examination of the dental arches.

Avaliação da superfície de braquetes de titânio após a aplicação de fluoreto de sódio

AIM: to assess and compare the effects of fluoride (NaF 1.23%) on titanium and stainless steel brackets. METHODS: Fifteen titanium brackets, divided in 3 groups were used: A) control group (no treatment on its surface), B) brackets immersed in NaF (60 seconds) and washed with distilled water (30 seconds), C) brackets with similar treatment to group B and submitted to brushing (15 seconds). Fifteen stainless steel brackets were used for comparative effects, divided in 3 groups, and submitted to the same described procedures. All brackets were evaluated by macroscopic (visual appearence) and scanning microscopy (Philips, model XL 30), before and after the procedures. RESULTS: titanium brackets submitted to fluoride (NaF), groups B and C, presented discoloration (matte gray color) when compared to group A. Stainless steel brackets showed no color alteration. CONCLUSION: titanium and stainless steel brackets showed no change in surface roughness or chemical components when immersed in sodium fluoride solution.