Influence of design implant and apical depth in post-extraction sockets: an in vitro simulated study.

BACKGROUND: Implant design and apical stability are principal parameters involved in achieving successful primary stability. Using polyurethane models to simulate post-extraction sockets, we investigated the effects of using differing blade designs on the primary stability of tapered implants and the impact of apical depth. METHOD: Six polyurethane blocks were used to simulate post-extraction pockets. One of the implants presented self-tapping blades (Group A), while the other (Group B) did not. Seventy-two implants were placed at 3 different depths (5 mm, 7 mm, and 9 mm), and a torque wrench was used to measure the stability of the implants. RESULTS: When evaluating the implants (placed at 5 mm, 7 mm, and 9 mm apical to the socket), we observed that the torque of the Group B implants was higher than that of Group A implants (P < 0.01). At the 9-mm depth, there was no difference between the groups (Drive GM 34.92 Ncm and Helix GM 32.33 Ncm) (P > 0.001), and considering the same implant groups, those placed at 7-mm and 9-mm depths presented higher torques (p < 0.01) than those placed at 5-mm (p > 0.01). CONCLUSION: Considering both groups, we concluded that an insertion depth of greater than 7 mm is needed for initial stability, and in situations involving reduced supportive bone tissue or low bone density, a non-self-tapping thread design improves implant stability.

Does Subcrestal Position Affect Insertion Torque of Different Implant Designs at Different Bone Densities? An In Vitro Model Study.

PURPOSE: To evaluate the insertion torque at the equicrestal and subcrestal positions of three implant designs in synthetic polyurethane blocks simulating different bone conditions. MATERIALS AND METHODS: Overall, 72 implants with three different designs (two conical and one cylindrical) were inserted at equicrestal and subcrestal positions (-2 mm) into polyurethane blocks simulating the anterior (0.32 g/cm3) and posterior (0.48 g/cm3) regions of the maxilla. The final insertion torque of all implants was measured using a digital torque meter, and the results were evaluated and statistically analyzed. RESULTS: For all implant systems, insertion torque decreased significantly when placed at the subcrestal position (P < .05), except for cylindrical implants placed in the bone blocks with high cancellous density. The implants with higher body conicity and square threads had higher insertion torque values than the cylindrical and conical implants with a lower body conical angle and trapezoidal threads. The implants inserted into higher-density blocks showed greater stability. CONCLUSION: The different implant systems lost insertion torque in a nonuniform manner at the subcrestal position and varied according to bone density. Implant design significantly influenced the initial stability at the equicrestal and subcrestal positions, especially in lower-density bone.

Effects of Pterygomaxillary Separation on Skeletal and Dental Changes After Surgically Assisted Rapid Maxillary Expansion: A Single-Center, Double-Blind, Randomized Clinical Trial.

PURPOSE: Surgically assisted rapid maxillary expansion (SARME) is a procedure routinely performed to correct transverse maxillary deformities and can be performed with or without pterygomaxillary disjunction (PD). The aim of the present study was to measure the effect of the amount of expansion and stability of SARME with or without PD. PATIENTS AND METHODS: We designed and implemented a double-blind, randomized clinical trial. The patients were randomly assigned to 2 groups: group 1, SARME without PD; and group 2, SARME with PD. Cone-beam computed tomography scans were performed at 3 points: baseline (T0), after maxillary expansion (T1), and at the end of the retention period (T2). Dental and bone expansion and dental inclination at the maxillary canine and first molar regions were assessed. Two-way repeated measures analysis of variance was used to evaluate the differences between the 2 groups at the 3 evaluation periods (T0, T1, and T2), using a level of significance of P < .05. RESULTS: A total of 24 patients underwent maxillary surgical expansion (group 1, n = 12; and group 2, n = 12). Both techniques promoted a significant transverse dental expansion in the first molar at T2 (with PD, 5.4 mm; vs without PD, 6.4 mm; change, -6.18 mm to 1.48 mm). However, no statistically significant differences were observed between the 2 groups. The tipping molars at T2 remained at a higher level in the SARME, no PD group than in the SARME, PD group (with PD, 2.3°; vs no PD, 4.6° for 3 teeth; change, -12.72° to 5.57°; and with PD, 1.6° vs without PD, 3.6° for 14 teeth; change, -9.96° to 9.83°). CONCLUSIONS: SARME with and without PD is a reliable method for obtaining maxillary expansion, with slight differences in the patterns of skeletal and dental alterations.

Peripheral osteoma bilateral of the mandible without association with Gardner syndrome.

Periosteal osteoma is a rare benign pathologic lesion in the jaws and the mandible is the anatomic region most frequently involved. Elective treatment consists of surgical excision. The aim of this report was to report a rare case of bilateral periosteal osteoma involving the mandible--a painless, firm, and well-circumscribed lesion, with more bony prominence on the left than on the right side. The patient had no history of facial trauma or systemic changes that could intervene with the progression of the lesion. It was diagnosed as a periosteal osteoma, and surgical excision was performed. No recurrence after 4 years of follow-up was demonstrated. Surgical excision of the periosteal osteoma was demonstrated to be a useful technical strategy that simplifies and accelerates the surgical procedures and probably contributes to establish harmony of the jaws. Periodical clinical and radiographic follow-ups after surgery are advised.

Assessment of the oral and maxillofacial surgery service in a teaching hospital in Brazil.

OBJECTIVE: The purpose of this study was to determine an epidemiologic profile of the patients hospitalized and/or operated on by an oral and maxillofacial surgery service in Brazil. MATERIALS AND METHODS: A retrospective and descriptive epidemiologic survey of the Oral and Maxillofacial Surgery Service from Saint Lucas Hospital at the Pontifical Catholic University, Porto Alegre, Brazil, from January 2000 to December 2005, was performed. Data related to the number, sex, age, service year, as well as surgical modalities performed, instituted treatments, and length of stay, were collected from the hospital's handbooks. RESULTS: A total of 1117 patients were attended during the 6 years of study, with a decreasing tendency throughout the years (P = 0.022). There was female predominance (54%), between 10 and 40 years old, and attended via public health system (56%). Among surgical modalities performed, dentoalveolar surgery was the most prevalent (22.9%), followed by the orthognathic surgeries (21.4%), facial fractures (18%), pathologic condition surgeries (16.7%), and dental implants and grafts (13.7%). Surgeries of patients with cleft lip and/or palate (3.4%), treatment of maxillofacial infections (2.95%), and temporomandibular joint surgeries (1%) were less frequent. CONCLUSIONS: The information presented in this research elicited data to clarify the type of attendance performed by the service, being a cornerstone for planning, organization, and attention improvement of these patients. In addition, this information can compare with data among services, specialty acting fields, as well as, its impact in hospital activities.

Enucleação de adenoma pleomórfico: considerações terapêuticas e relato de caso / Enucleation of pleomorphic adenoma: therapeutic considerations and case report

O adenoma pleomórfico é o tumor benigno que representa cerca de 70 a 90% dos tumores das glândulas salivares. A parótida é a glândula salivar mais afetada, seguida das glândulas salivares menores localizadas na região posterolateral do palato. O tratamento de eleição consiste na excisão cirúrgica da lesão, com pequena margem de segurança, em virtude da grande possibilidade de recidiva, caso permaneçam células tumorais após enucleação. Este trabalho tem por objetivo relatar um caso clínico de adenoma pleomórfico localizado na região posterolateral,na junção entre os palatos duro e mole, tratado através de excisão cirúrgica. Os autores apresentam uma complicação pós-operatória dada pela necrose do tecido de fina espessura remanescente, na região de palato mole, após enucleação do adenoma, causando uma fístula buconasal de aproximadamente 5 mm. O fechamento desta fístula ocorreu pela reepitelização por segunda intenção, com integridade epitelial observada aos cinco meses do pósoperatório. Após quatro anos de acompanhamento, não existem evidências clínicas de recidiva tumoral.

The pleomorphic adenoma a benign tumor that represents around 70 to 90% of salivary gland tumors. The parotid is the gland most affected, followed by the minor salivary glands located in the posterolateral region ofthe palate. The treatment of choice is surgical excision of the lesion with a small margin of safety in view of the strong possibility of recurrence if tumor cells remain after enucleation. The purpose of this paper is to report a clinical case of pleomorphic adenoma in the posterolateral region at the junction between the hard and soft palates, treated by surgical excision. The authors present a postoperative complication caused by the necrosisof the thin remaining tissue in the region of the soft palate following enucleation of the adenoma, causing an oronasal fistula of approximately 5 mm. The closure of this fistula occurred as a result of reepithelialization by second intention, observed five months after surgery. After 4 years of follow-up there is no evidence of recurrence of the tumor.

Enucleação de Adenoma Plemórfico: considerações terapêuticas e ralato de caso / Enuclation of Pleomorphic Adenoma: Therapeutic Considerations an Case Report

O adenoma pleomórfico é o tumor benigno que representa cerca de 70 a 90% dos tumores das glândulas salivares.A parótida é a glândula salivar mais afetada, seguida das glândulas salivares menores localizadas na região posterolateral do palato. O tratamento de eleição consiste na excisão cirúrgica da lesão, com pequena margem de segurança, em virtude da grande possibilidade de recidiva, caso permaneçam células tumorais após enucleação. Este trabalho tem por objetivo relatar um caso clínico de adenoma pleomórfico localizado na região posterolateral,na junção entre os palatos duro e mole, tratado através de excisão cirúrgica. Os autores apresentam uma complicação pós-operatória dada pela necrose do tecido de fina espessura remanescente, na região de palato mole, após enucleação do adenoma, causando uma fístula buconasal de aproximadamente 5 mm. O fechamento desta fístula ocorreu pela reepitelização por segunda intenção, com integridade epitelial observada aos cinco meses do pós operatório. Após quatro anos de acompanhamento, não existem evidências clínicas de recidiva tumoral

Estudo comparativo das avaliações cefalométrica do perfil dentoesquélito maxilar e perfil mole nasolabial de indivíduos de diferentes etnias / Comparative study of variations cephalometrics of the tooth skeleton maxilar profile and soft nasolabial profile of individuals of differents ethinics

Objetivo: Partindo do pressuposto que o padrão cefalométricodeve ser étnico-específico, esta pesquisa realizou um estudocomparativo entre dimensões cefalométricas lineares eangulares de pontos anatômicos relacionados com o perfildentoesquelético maxilar e perfil mole nasolabial. Método: Asamostras que compuseram o estudo foram obtidas a partir detelerradiografias, em norma lateral, e agrupadas de acordo comas etnias branca e negra, cada uma com 20 indivíduos. Asradiografias foram submetidas à análise cefalométricacomputadorizada de Ricketts, utilizando o Programa Radiocef2.0®. Os valores alcançados tiveram tratamento estatístico,utilizando o teste paramétrico Anova, considerando p=0,05.Resultados: As dimensões cefalométricas que expressamdistância do ponto A ao ponto subnasal, comprimento do lábiosuperior, inclinação dos dentes incisivos superiores e o ângulonasolabial são as mais representativas das diferenças entre asetnias estudadas. Conclusão: Existem diferençasestatisticamente significativas entre as dimensõescefalométricas lineares e angulares entre os indivíduosleucodermos e melanodermos, indicando que a estrutura facialdo negro é maior que a dos indivíduos brancos, econseqüentemente atribui-se um perfil convexo, decorrentesdo posicionamento maxilar, dentário e labial nestes indivíduos.Este estudo reforça a hipótese de que as normascefalométricas devem ser elaboradas para cada grupo racial, individualmente.