Does the maxillary midline diastema close after frenectomy?

OBJECTIVE To analyze the closure, persistence or reopening of the maxillary midline diastema after frenectomy in patients with and without subsequent orthodontic treatment. METHOD AND MATERIALS All patients undergoing frenectomy with a CO2 laser were included in this retrospective study during the period of September 2002 to June 2011. Age and sex, the dimension of the diastema, eruption status of the maxillary canines, and the presence of an orthodontic treatment were recorded at the day of frenectomy and during follow-up. RESULTS Of the 59 patients fulfilling the inclusion criteria, 31 (52.5%) had an active orthodontic therapy, while 27 (45.8%) had a frenectomy without orthodontic treatment. For one patient, information concerning orthodontic treatment was not available. In the first follow-up (2 to 12 weeks), only four diastemas closed after frenectomy and orthodontic treatment, and none after frenectomy alone. In the second follow-up (4 to 19 months), statistically significantly (P = .002) more diastemas (n = 20) closed with frenectomy and orthodontic treatment than with frenectomy alone (n = 3). At the long-term (21 to 121 months) follow-up, only four patients had a persisting diastema, and in three patients orthodontic treatment was ongoing. CONCLUSION Closure of the maxillary midline diastema with a prominent frenum is more predictable with frenectomy and concomitant orthodontic treatment than with frenectomy alone. This study demonstrates the importance of an interdisciplinary approach to treat maxillary midline diastemas, ideally including general practitioners, oral surgeons, periodontists, and orthodontists.

Indication and timing of soft tissue augmentation at maxillary and mandibular incisors in orthodontic patients. A systematic review.

OBJECTIVE To assess the indication and timing of soft tissue augmentation for prevention or treatment of gingival recession when a change in the inclination of the incisors is planned during orthodontic treatment. MATERIALS AND METHODS Electronic database searches of literature were performed. The following electronic databases with no restrictions were searched: MEDLINE, EMBASE, Cochrane, and CENTRAL. Two authors performed data extraction independently using data collection forms. RESULTS No randomized controlled trial was identified. Two studies of low-to-moderate level of evidence were included: one of prospective and retrospective data collection and one retrospective study. Both implemented a periodontal intervention before orthodontics. Thus, best timing of soft tissue augmentation could not be assessed. The limited available data from these studies appear to suggest that soft tissue augmentation of bucco-lingual gingival dimensions before orthodontics may yield satisfactory results with respect to the development or progression of gingival recessions. However, the strength of the available evidence is not adequate in order to change or suggest a possible treatment approach in the daily practice based on solid scientific evidence. CONCLUSIONS Despite the clinical experience that soft tissue augmentation of bucco-lingual gingival dimensions before orthodontic treatment may be a clinically viable treatment option in patients considered at risk, this treatment approach is not based on solid scientific evidence. Moreover, the present data do not allow to draw conclusions on the best timing of soft tissue augmentation when a change in the inclination of the incisors is planned during orthodontic treatment and thus, there is a stringent need for randomized controlled trials to clarify these open issues.

Bone dimensions in the posterior mandible: a retrospective radiographic study using cone beam computed tomography. Part 2- analysis of edentulous sites.

A precise radiographic evaluation of the local bone dimensions and morphology is important for preoperative planning of implant placement. The purpose of this retrospective study was to analyze dimensions and morphology of edentulous sites in the posterior mandible using cone beam computed tomography (CBCT) images. This retrospective radiographic study measured the bone width (BW) of the mandible at three locations on CBCT scans for premolars (PM1, PM2) and molars (M1, M2): at 1 mm and 4 mm below the most cranial point of the alveolar crest (BW1, BW2) and at the superior border of the mandibular canal (BW3). Furthermore, the height (H) of the alveolar process (distance between the measuring points BW1 and BW3), as well as the presence of lingual undercuts, were analyzed. A total of 56 CBCTs met the inclusion criteria, resulting in a sample size of 127 cross sections. There was a statistically significant increase from PM1 to M2 for the BW2 (P < .001), which was not present for BW1 and BW3 values. For the height of the alveolar process, the values exhibited a decrease from PM1 to M2 sites. Sex was a statistically significant parameter for H (P = .001) and for BW1 (P = .03). Age was not a statistically significant parameter for bone width (BW1: P = .37; BW2: P = .31; BW3: P = .51) or for the height of the alveolar process (P = .41) in the posterior mandible. Overall, 73 (57.5%) edentulous sites were evaluated to be without visible lingual undercuts; 13 (10.2%) sites exhibited lingual undercuts classified as influential for implant placement. Precise evaluation of the alveolar crest by cross-sectional imaging is of great value to analyze vertical and buccolingual bone dimensions in different locations in the posterior mandible. In addition, CBCTs are valuable to diagnosing the presence of and potential problems caused by lingual undercuts prior to implant placement.

Susceptibility of enamel to initial erosion in relation to tooth type, tooth surface and enamel depth

This study aimed at assessing the susceptibility of different tooth types (molar/premolar), surfaces (buccal/lingual) and enamel depths (100, 200, 400 and 600 μm) to initial erosion measured by surface microhardness loss (ΔSMH) and calcium (Ca) release. Twenty molars and 20 premolars were divided into experimental and control groups, cut into lingual/ buccal halves, and ground/polished, removing 100 μm of enamel. The initial surface microhardness (SMH 0 ) was measured on all halves. The experimental group was subjected to 3 consecutive erosive challenges (30 ml/tooth of 1% citric acid, pH 3.6, 25 ° C, 1 min). After each challenge, ΔSMH and Ca release were measured. The same teeth were consecutively ground to 200, 400 and 600 μm depths, and the experimental group underwent 3 erosive challenges at each depth. No difference was found in SMH 0 between experimental and control groups. Multivariate nonparametric ANOVA showed no significant differences between lingual and buccal surfaces in ΔSMH (p = 0.801) or Ca release (p = 0.370). ΔSMH was significantly greater in premolars than in molars (p < 0.05), but not different with respect to enamel depth. Ca release decreased significantly with increasing depth. Regression between Ca release and ΔSMH at 100 μm depth showed lower slope and r 2 value, associated with greater Ca release values. At 200-600 μm depths, moderately large r 2 values were observed (0.651-0.830). In conclusion, different teeth and enamel depths have different susceptibility to erosion, so when Ca release is used to measure erosion, the depth of the test facet in enamel should be standardized, whereas this is less important if ΔSMH is used.

Periodontal regeneration - furcation defects: a consensus report from the AAP Regeneration Workshop

BACKGROUND Treatment of furcation defects is a core component of periodontal therapy. The goal of this consensus report is to critically appraise the evidence and to subsequently present interpretive conclusions regarding the effectiveness of regenerative therapy for the treatment of furcation defects and recommendations for future research in this area. METHODS A systematic review was conducted before the consensus meeting. This review aims to evaluate and present the available evidence regarding the effectiveness of different regenerative approaches for the treatment of furcation defects in specific clinical scenarios compared with conventional surgical therapy. During the meeting, the outcomes of the systematic review, as well as other pertinent sources of evidence, were discussed by a committee of nine members. The consensus group members submitted additional material for consideration by the group in advance and at the time of the meeting. The group agreed on a comprehensive summary of the evidence and also formulated recommendations for the treatment of furcation defects via regenerative therapies and the conduction of future studies. RESULTS Histologic proof of periodontal regeneration after the application of a combined regenerative therapy for the treatment of maxillary facial, mesial, distal, and mandibular facial or lingual Class II furcation defects has been demonstrated in several studies. Evidence of histologic periodontal regeneration in mandibular Class III defects is limited to one case report. Favorable outcomes after regenerative therapy for maxillary Class III furcation defects are limited to clinical case reports. In Class I furcation defects, regenerative therapy may be beneficial in certain clinical scenarios, although generally Class I furcation defects may be treated predictably with non-regenerative therapies. There is a paucity of data regarding quantifiable patient-reported outcomes after surgical treatment of furcation defects. CONCLUSIONS Based on the available evidence, it was concluded that regenerative therapy is a viable option to achieve predictable outcomes for the treatment of furcation defects in certain clinical scenarios. Future research should test the efficacy of novel regenerative approaches that have the potential to enhance the effectiveness of therapy in clinical scenarios associated historically with less predictable outcomes. Additionally, future studies should place emphasis on histologic demonstration of periodontal regeneration in humans and also include validated patient-reported outcomes. CLINICAL RECOMMENDATIONS Based on the prevailing evidence, the following clinical recommendations could be offered. 1) Periodontal regeneration has been established as a viable therapeutic option for the treatment of various furcation defects, among which Class II defects represent a highly predictable scenario. Hence, regenerative periodontal therapy should be considered before resective therapy or extraction; 2) The application of a combined therapeutic approach (i.e., barrier, bone replacement graft with or without biologics) appears to offer an advantage over monotherapeutic algorithms; 3) To achieve predictable regenerative outcomes in the treatment of furcation defects, adverse systemic and local factors should be evaluated and controlled when possible; 4) Stringent postoperative care and subsequent supportive periodontal therapy are essential to achieve sustainable long-term regenerative outcomes.

Visor Osteotomy of the Anterior Mandible

Current techniques for three-dimensional correction of the chin in patients with mandibular retrusion may increase mentolabial fold depth, but have limited effect on the lips. The authors present a single surgical technique to support the mentolabial fold and improve labial competence. The visor osteotomy is performed from canine to canine. The bone fragment pedicled to the lingual periosteum is coronally mobilized and fixed in the new position. Preserved vascularization is supposed to minimize the amount of bone resorbed. Visor osteotomy of the anterior mandible may improve the existing treatments for micrognathia by creating an aesthetic mentolabial fold and a competent lip seal.

Space requirement of a prefabricated bar on two interforaminal implants: a prospective clinical study

OBJECTIVES This clinical study measured the dimensional changes of existing lower complete dentures due to the integration of a prefabricated implant bar. Additionally, the impact of this dimensional change on patient satisfaction and oral function was analyzed. METHODS Twenty edentulous patients (10 men/10 women; aged 65.9 ± 11.8 years) received two interforaminal implants. Subsequent to surgery, a chair side adapted, prefabricated bar (SFI Bar(®), C+M, Biel, Switzerland) was inserted, and the matrix was polymerized into the existing lower denture. The change of the denture's lingual dimension was recorded by means of a bicolored, silicone denture duplicate that was sectioned in the oro-vestibular direction in the regions of the symphysis (S) and the implants (I-left, I-right). On the sections, the dimensional increase was measured using a light microscope. Six months after bar insertion, patients answered a standardized questionnaire. RESULTS All dentures exhibited increased lingual volume, more extensively at S than at I (P = 0.001). At S, the median diagonal size of the denture was doubled (+4.33 mm), and at I, the median increase was 50% (I-left/-right = +2.66/+2.62 mm). The original denture size influenced the volume increase (P = 0.024): smaller dentures led to a larger increase. The amount of denture increase did not have negative impact on either self-perceived oral function or patient satisfaction. Approximately, 95% of the patients were satisfied with the treatment results. CONCLUSIONS The lingual size of a lower denture was enlarged by the integration of a prefabricated bar without any negative side effects. Thus, this attachment system is suitable to convert an existing full denture into an implant-supported overdenture.

Dislocated Tongue Muscle Attachment and Cleft Palate Formation

In Pierre Robin sequence, a retracted tongue due to micrognathia is thought to physically obstruct palatal shelf elevation and thereby cause cleft palate. However, micrognathia is not always associated with palatal clefting. Here, by using the Bmp7-null mouse model presenting with cleft palate and severe micrognathia, we provide the first causative mechanism linking the two. In wild-type embryos, the genioglossus muscle, which mediates tongue protrusion, originates from the rostral process of Meckel's cartilage and later from the mandibular symphysis, with 2 tendons positive for Scleraxis messenger RNA. In E13.5 Bmp7-null embryos, a rostral process failed to form, and a mandibular symphysis was absent at E17.5. Consequently, the genioglossus muscle fibers were diverted toward the lingual surface of Meckel's cartilage and mandibles, where they attached in an aponeurosis that ectopically expressed Scleraxis. The deflection of genioglossus fibers from the anterior-posterior toward the medial-lateral axis alters their direction of contraction and necessarily compromises tongue protrusion. Since this muscle abnormality precedes palatal shelf elevation, it is likely to contribute to clefting. In contrast, embryos with a cranial mesenchyme-specific deletion of Bmp7 (Bmp7:Wnt1-Cre) exhibited some degree of micrognathia but no cleft palate. In these embryos, a rostral process was present, indicating that mesenchyme-derived Bmp7 is dispensable for its formation. Moreover, the genioglossus appeared normal in Bmp7:Wnt1-Cre embryos, further supporting a role of aberrant tongue muscle attachment in palatal clefting. We thus propose that in Pierre Robin sequence, palatal shelf elevation is not impaired simply by physical obstruction by the tongue but by a specific developmental defect that leads to functional changes in tongue movements.

MIRACLE at Ad-Hoc CLEF 2005: Merging and Combining Without Using a Single Approach

This paper presents the 2005 Miracle’s team approach to the Ad-Hoc Information Retrieval tasks. The goal for the experiments this year was twofold: to continue testing the effect of combination approaches on information retrieval tasks, and improving our basic processing and indexing tools, adapting them to new languages with strange encoding schemes. The starting point was a set of basic components: stemming, transforming, filtering, proper nouns extraction, paragraph extraction, and pseudo-relevance feedback. Some of these basic components were used in different combinations and order of application for document indexing and for query processing. Second-order combinations were also tested, by averaging or selective combination of the documents retrieved by different approaches for a particular query. In the multilingual track, we concentrated our work on the merging process of the results of monolingual runs to get the overall multilingual result, relying on available translations. In both cross-lingual tracks, we have used available translation resources, and in some cases we have used a combination approach.

Challenges for the Multilingual Web of Data

The Web has witnessed an enormous growth in the amount of semantic information published in recent years. This growth has been stimulated to a large extent by the emergence of Linked Data. Although this brings us a big step closer to the vision of a Semantic Web, it also raises new issues such as the need for dealing with information expressed in different natural languages. Indeed, although the Web of Data can contain any kind of information in any language, it still lacks explicit mechanisms to automatically reconcile such information when it is expressed in different languages. This leads to situations in which data expressed in a certain language is not easily accessible to speakers of other languages. The Web of Data shows the potential for being extended to a truly multilingual web as vocabularies and data can be published in a language-independent fashion, while associated language-dependent (linguistic) information supporting the access across languages can be stored separately. In this sense, the multilingual Web of Data can be realized in our view as a layer of services and resources on top of the existing Linked Data infrastructure adding i) linguistic information for data and vocabularies in different languages, ii) mappings between data with labels in different languages, and iii) services to dynamically access and traverse Linked Data across different languages. In this article we present this vision of a multilingual Web of Data. We discuss challenges that need to be addressed to make this vision come true and discuss the role that techniques such as ontology localization, ontology mapping, and cross-lingual ontology-based information access and presentation will play in achieving this. Further, we propose an initial architecture and describe a roadmap that can provide a basis for the implementation of this vision.

ESTUDO DAS ANGULAÇÕES E INCLINAÇÕES DENTÁRIAS OBTIDAS NO TRATAMENTO ORTODÔNTICO COM A UTILIZAÇÃO DA PRESCRIÇÃO MB

O presente trabalho tem o objetivo de verificar as angulações e as inclinações dentárias obtidas no final do tratamento ortodôntico, em casos tratados com aparelho ortodôntico fixo e prescrição MBT e compará-las com os valores encontrados por Andrews para a oclusão normal natural. Foram utilizados 30 pares de modelos de gesso finais, de 30 pacientes, tratados, na faixa etária de 13 a 23 anos. Como pré-requisitos, estes pacientes não deveriam ter sido submetidos a qualquer tipo de intervenção ortopédica, uso de elásticos intermaxilares, compensações dento-alveolares e tratamentos realizados com extração. Para a mensuração da angulação mésio-distal e da inclinação vestíbulo-lingual utilizou-se um dispositivo, desenvolvido em pesquisa anterior, capaz de realizar tais medições. De acordo com a metodologia empregada e diante dos resultados obtidos, pôde-se concluir que as angulações das coroas dentárias tanto superiores quanto inferiores apresentaram valores positivos. Quanto às inclinações das coroas dentárias, em ambos os arcos dentários, foram encontrados valores positivos para os incisivos centrais e laterais, ao passo que caninos, pré-molares e primeiros molares apresentaram valore s negativos. Variações individuais estiveram presentes nas duas mensurações realizadas. Ao comparar nossos resultados com os de Andrews, obtivemos diferenças estatisticamente significantes para a maioria dos dentes, em ambas as medidas efetuadas.

ESTUDO DAS ANGULAÇÕES E INCLINAÇÕES DENTÁRIAS OBTIDAS NO TRATAMENTO ORTODÔNTICO COM A UTILIZAÇÃO DA PRESCRIÇÃO MB

O presente trabalho tem o objetivo de verificar as angulações e as inclinações dentárias obtidas no final do tratamento ortodôntico, em casos tratados com aparelho ortodôntico fixo e prescrição MBT e compará-las com os valores encontrados por Andrews para a oclusão normal natural. Foram utilizados 30 pares de modelos de gesso finais, de 30 pacientes, tratados, na faixa etária de 13 a 23 anos. Como pré-requisitos, estes pacientes não deveriam ter sido submetidos a qualquer tipo de intervenção ortopédica, uso de elásticos intermaxilares, compensações dento-alveolares e tratamentos realizados com extração. Para a mensuração da angulação mésio-distal e da inclinação vestíbulo-lingual utilizou-se um dispositivo, desenvolvido em pesquisa anterior, capaz de realizar tais medições. De acordo com a metodologia empregada e diante dos resultados obtidos, pôde-se concluir que as angulações das coroas dentárias tanto superiores quanto inferiores apresentaram valores positivos. Quanto às inclinações das coroas dentárias, em ambos os arcos dentários, foram encontrados valores positivos para os incisivos centrais e laterais, ao passo que caninos, pré-molares e primeiros molares apresentaram valore s negativos. Variações individuais estiveram presentes nas duas mensurações realizadas. Ao comparar nossos resultados com os de Andrews, obtivemos diferenças estatisticamente significantes para a maioria dos dentes, em ambas as medidas efetuadas.

Estudo cefalométrico-radiográfico das alterações dento-esqueléticas em pacientes com má oclusão de Classe III submetidos a tratamento ortodôntico-cirúrgico

Este estudo teve como finalidade avaliar cefalometricamente, por meio de telerradiografias em norma lateral, as alterações dento-esqueléticas em pacientes Classe III submetidos a tratamento ortodôntico-cirúrgico. A amostra experimental constituiu-se de 16 pacientes Brasileiros, dos sexos masculino e feminino, na faixa etária pré-cirúrgica média de 21 anos e 11 meses, apresentando má oclusão de Classe III com indicação de tratamento cirúrgico representado por recuo mandibular isolado. Para cada paciente foram realizadas telerradiografias nas fases inicial, pré-cirúrgica e pós-cirúrgica, sendo comparadas a um grupo controle, constituído de telerradiografias de indivíduos com oclusão normal. Segundo a metodologia empregada e pela análise dos resultados obtidos, avaliados estatisticamente, constatou-se que os pacientes Classe III com indicação de recuo mandibular foram caracterizados por um mau relacionamento entre as bases esqueléticas representado por um bom posicionamento da maxila associado a prognatismo mandibular, aumento da altura facial ântero-inferior, incisivos inferiores e sínfise mandibular lingualizados e incisivos superiores vestibularizados. A partir do preparo ortodôntico pré-cirúrgico, observou-se uma rotação mandibular no sentido horário, descompensação dentária representada por lingualização e extrusão dos incisivos superiores e vestibularização dos incisivos inferiores, acompanhada por uma remodelação da cortical óssea vestibular da sínfise mandibular. Esta descompensação ortodôntica definiu características dento-alveolares semelhantes às dos indivíduos com oclusão normal. O comportamento das variáveis dento-esqueléticas após a cirurgia ortognática, a partir do deslocamento póstero-superior das estruturas dento-esqueléticas da mandíbula, proporcionou um equilíbrio destas estruturas, em relação à oclusão normal.

Estudo cefalométrico-radiográfico das alterações dento-esqueléticas em pacientes com má oclusão de Classe III submetidos a tratamento ortodôntico-cirúrgico

Este estudo teve como finalidade avaliar cefalometricamente, por meio de telerradiografias em norma lateral, as alterações dento-esqueléticas em pacientes Classe III submetidos a tratamento ortodôntico-cirúrgico. A amostra experimental constituiu-se de 16 pacientes Brasileiros, dos sexos masculino e feminino, na faixa etária pré-cirúrgica média de 21 anos e 11 meses, apresentando má oclusão de Classe III com indicação de tratamento cirúrgico representado por recuo mandibular isolado. Para cada paciente foram realizadas telerradiografias nas fases inicial, pré-cirúrgica e pós-cirúrgica, sendo comparadas a um grupo controle, constituído de telerradiografias de indivíduos com oclusão normal. Segundo a metodologia empregada e pela análise dos resultados obtidos, avaliados estatisticamente, constatou-se que os pacientes Classe III com indicação de recuo mandibular foram caracterizados por um mau relacionamento entre as bases esqueléticas representado por um bom posicionamento da maxila associado a prognatismo mandibular, aumento da altura facial ântero-inferior, incisivos inferiores e sínfise mandibular lingualizados e incisivos superiores vestibularizados. A partir do preparo ortodôntico pré-cirúrgico, observou-se uma rotação mandibular no sentido horário, descompensação dentária representada por lingualização e extrusão dos incisivos superiores e vestibularização dos incisivos inferiores, acompanhada por uma remodelação da cortical óssea vestibular da sínfise mandibular. Esta descompensação ortodôntica definiu características dento-alveolares semelhantes às dos indivíduos com oclusão normal. O comportamento das variáveis dento-esqueléticas após a cirurgia ortognática, a partir do deslocamento póstero-superior das estruturas dento-esqueléticas da mandíbula, proporcionou um equilíbrio destas estruturas, em relação à oclusão normal.

ESTUDO DAS FORMAS E DIMENSÕES LINGUAIS DAS ARCADAS DENTÁRIAS EM INDIVÍDUOS BRASILEIROS COM OCLUSÃO NORMAL

A preocupação com o estudo das formas e dimensões das arcadas dentárias sempre esteve presente na ciência ortodôntica. Para a Ortodontia Lingual, que surgiu no final da década de 70, o primeiro artigo publicado foi o Fujita, onde relatou sobre a forma do arco a ser utilizado nesta técnica, a forma de cogumelo. Apesar de estar sendo divulgada de uma maneira mais intensa nestes últimos anos como uma solução estética definitiva e eficaz, o enfoque dos estudos sobre esta técnica tem sido a fabricação de novos materiais, técnicas de montagem do aparelho lingual e soluções clínicas, com poucas menções sobre a morfologia das arcadas dentárias. O presente trabalho tem a finalidade de estudar as formas e dimensões linguais das arcadas dentárias de indivíduos leucodermas com oclusão normal. Foram utilizados 47 pares de modelos de gesso de oclusão normal digitalizados pela face olcusal, previamente desgastadas até o terço médio da coroa para proporcionar melhor visualização. Por meio do programa CorelDraw 12 foram determinados pontos de referências e criados alguns pontos virtuais necessários para a realização das medidas. Os resultados determinaram três formas das arcadas dentárias linguais: cogumelo, árvore de Natal e mista. A maior prevalência foi a forma árvore de Natal, mas quando analisadas separadamente as arcadas dentárias linguais, encontrados no superior, maior prevalência da forma de cogumelo e no inferior da forma árvore de Natal. Conseqüentemente, esta foi a combinação mais prevalente entre as arcadas dentárias linguais superiores e inferiores. Propusemos diagramas para conformação de arcos ortodônticos linguais com base nos valores obtidos da amostra, determinando-se o quartil 1, mediana e quartil 3, como definidores dos tamanhos pequeno, médio e grande.