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Drilling dimension effects in early stages of osseointegration and implant stability in a canine model

  • Baires Campos, Felipe Eduardo
  • Jimbo, Ryo
  • Bonfante, Estevam A.
  • Fonseca Oliveira, Maiolino Thomaz
  • Moura, Camila
  • Zanetta Barbosa, Darceny
  • Coelho, Paulo G.
Background: This study histologically evaluated two implant designs: a classic thread design versus another specifically designed for healing chamber formation placed with two drilling protocols. Material and Methods: Forty dental implants (4.1 mm diameter) with two different macrogeometries were inserted in the tibia of 10 Beagle dogs, and maximum insertion torque was recorded. Drilling techniques were: until 3.75 mm (regular-group); and until 4.0 mm diameter (overdrilling-group) for both implant designs. At 2 and 4 weeks, samples were retrieved and processed for histomorphometric analysis. For torque and BIC (bone-to-implant contact) and BAFO (bone area fraction occupied), a general-linear model was employed including instrumentation technique and time in vivo as independent. Results: The insertion torque recorded for each implant design and drilling group significantly decreased as a function of increasing drilling diameter for both implant designs ( p <0.001). No significant differences were de - tected between implant designs for each drilling technique ( p >0.18). A significant increase in BIC was observed from 2 to 4 weeks for both implants placed with the overdrilling technique ( p <0.03) only, but not for those placed in the 3.75 mm drilling sites ( p >0.32). Conclusions: Despite the differences between implant designs and drilling technique an intramembranous-like healing mode with newly formed woven bone prevailed

Survival of immediately versus delayed loaded short implants: a prospective case series study

  • Alvira González, Joaquín
  • Díaz Campos, Erick
  • Sánchez Garcés, María Angeles
  • Gay Escoda, Cosme
Background: To assess and compare survival rates of immediately and delayed loaded short implants (7 mm) in free ends of a partially edentulous jaw with moderate-severe alveolar bone resorption. Material and Methods: 24 patients with atrophic edentulous free-ends were included in this prospective study. Four study groups were monitored monthly and their behavior was evaluated: bridges supported only by short implants and mixed short and long implant bridge groups, both with immediate and delayed loading. Failures, bone loss, probing depth and bleeding on probing were evaluated. Results: 54 Mk III Shorty TiU and 15 Brånemark System®MK III TiU implants with a length longer than 7mm were included in the study. Twenty-eight implants were inserted following the immediate loading protocol and 26 according a two-stage procedure, depending on the torque value. The cumulative survival rate of short implants was 87% (n=54) after a mean time of 47.72 months (range 33-62 months), showing statistically significant differences related to loading protocol ( p =0.047). Short implants immediately loaded had a higher long-term survival rate (96.4%) compared to the other study group (76.9%). Besides, short implants splinted to longer immediately loaded implants presented the highest survival rate (100%). Twenty-five (53.19%) short implants showed a bone loss of less than one millimeter after the follow-up period. Statistically significant differences were found between bleeding on probing, presence of plaque or suppuration and a higher bone loss in both loading protocols ( p = 0.0 01). Conclusions: Immediate loading of short implants placed on free ends can be considered an option in the treatment protocol of patients with severe bone resorption especially if implants are splinted to others of greater length.

Intermittent administration of parathyroid hormone improves the repairing process of rat calvaria defects: a histomorphometric and radiodensitometric study

  • Silva, Eduardo de Paula
  • Vasconcelos, Daniel Fernando Pereira
  • Marques, Marcelo Rocha
  • Dias da Silva, Marco Antonio
  • Manzi, Flávio Ricardo
  • Barros, Silvana Pereira
Background: The aim of this study was to evaluate the effects of intermittent treatment of parathyroid hormone (PTH (1-34)) on the bone regeneration of critically-sized rat calvarial bone defects. Material and Methods: Thirty-two male rats were trephined (4mm fullthickness diameter), in the central part of the parietal bones and divided into 2 groups of 16. The PTH group received subcutaneous injections of PTH (1-34) at 40μg/kg, 3 times a week and the control (CTL) group received the vehicle in the same regimen. The rats were sacrificed at 4 weeks post-treatment regimen, the parietal bones were extracted and samples were evaluated through histomorphometry and radiodensitometry. Results: The histological observations showed that the PTH group presented more “island-like” new bone between the defect margins with fibrous tissues than did the CTL group. The PTH group significantly exhibited greater histologic bone formation than did the CTL group (1.5mm ±0.7; 1.9 mm ± 0.6, p <0.05/ for residual bone defect). The radiodensitometry analysis revealed significant differences among the PTH and CTL groups (2.1 Al eq. ±0.04; 1.8Al eq. ±0.06, p <0.05), demonstrating an increase in bone mineral density. The PTH treatment contributed to the bone formation with a higher amount of mineral and/or fibrous tissue when compared with the CTL group. Conclusions: The results suggest that it was possible to increase the process of bone regeneration by accelerating the healing process in rat calvarial defects through intermittent administration of the PTH treatment.

Is the Erich arch bar the best intermaxillary fixation method in maxillofacial fractures? : a systematic review

  • Falci, Saulo Gabriel
  • Douglas de Oliveira, Dhelfeson Willya
  • Stella, Paulo Eduardo Melo
  • Rocha dos Santos, Cássio Roberto
Background: Intermaxillary fixation is used to achieve proper occlusion during and after oral and maxillofacial fracture surgery. The aim of this systematic review was to compare Erich arch bar fixation with other intermaxillary fixation methods in terms of the operating time, safety during installation, oral health maintenance and occlusal stability. Material and Methods: An electronic online search was conducted of the Scirus, PubMed, Ovid, Cochrane Library and VHL databases. A clinical trial dating from the inception of the data bases until August 2013 was selected. Studies that compared Erich arch bars with other intermaxillary fixation methods in patients older than 18 years-old were included. The studies were assessed by two independent reviewers. The methodological quality of each article was analyzed. Results: Nine hundred and twenty-five manuscripts were found. Seven relevant articles were analyzed in this review. The risk of bias was considered moderate for four studies and high for three clinical trials. Conclusions: There is not enough evidence to conclude that the Erich arch bar is the best intermaxillary fixation method in cases of oral and maxillofacial fractures

Repair of complete bilateral cleft lip with severely protruding premaxilla performing a premaxillary setback and vomerine ostectomy in one stage surgery

  • Fakih Gomez, Nabil
  • Sanchez Sanchez, Marta
  • Iglesias Martin, Fernando
  • García-Perla García, Alberto
  • Belmonte Caro, Rodolfo
  • González Pérez, Luis Miguel
Background: The authors present a technique for selected cases of CBCL. The primary repair of the CBCL with a severely protruding premaxilla in one stage surgery is very difficult, essentially because a good muscular apposition is difficult, forcing synchronously to do a premaxillary setback to facilitate subsequent bilateral lip repair and, thus, achieving satisfactory results. We achieve this by a reductive ostectomy on the vomero- premaxillary suture. Material and Methods: 4 patients with CBCL and severely protruding premaxilla underwent premaxillary setback by vomerine ostectomy at the same time of lip repair in the past 24 months. The extent of premaxillary setback varied between 9 and 16 mm. The required amount of bone was removed anterior to the vomero-premaxillary suture. The authors did an additional simultaneous gingivoperiosteoplasty in all patients, achieving an enough stability of the premaxilla in its new position, to be able to close the alveolar gap bilaterally. The authors have examined the position of premaxilla and dental arch between 6 and 24 months. We did not do the primary nose correction, because this increased the risk of impairment of the already compromised vascularity of the philtrum and premaxilla. Results : The follow-up period ranged between 6 and 24 months. None of the patients had any major complication. During follow-up, the premaxilla was minimally mobile. We achieved a good lip repair in all cases: adequate muscle repair, symmetry of the lip, prolabium and Cupid’s bow, as well as good scars. Conclusions : To our knowledge, there are few reports of one stage surgery with vomerine ostectomy to repair CBCL with severely protruding premaxilla. Doing this vomerine ostectomy, we don’t know how it will affect the subsequent growth of the premaxila and restrict the natural maxillary growth. Applying this alternative treatment for children with CBCL and protruded premaxilla without any preoperative orthopedic, we can successfully perform, in a single-stage surgery, a good primary lip repair at our center. Further confirmations of this surgery with follow up and anthropometric studies of these patients during childhood and adolescence are required

Coronectomy versus surgical removal of the lower third molars with a high risk of injury to the inferior alveolar nerve: a bibliographical review

  • Moreno Vicente, Javier
  • Schiavone Mussano, Rocío
  • Clemente Salas, Enrique
  • Marí Roig, Antonio
  • Jane Salas, Enric
  • López López, José
Background: Coronectomy is the surgical removal of the crown of the tooth deliberately leaving part of its roots. This is done with the hope of eliminating the pathology caused, and since the roots are still intact, the integrity of the inferior alveolar nerve is preserved. Objective: The aim is to carry out a systematic review in order to be able to provide results and conclusions with the greatest scientific evidence possible. Material and Methods: A literature review is carried out through the following search engines: Pubmed MEDLINE, Scielo, Cochrane library and EMI. The level of evidence criteria from the Agency for Healthcare Research and Quality was applied, and the clinical trials’ level of quality was analyzed by means of the JADAD criteria. Results: The following articles were obtained which represents a total of 17: 1 systematic review, 2 randomized clinical trials and 2 non-randomized clinical trials, 3 cohort studies, 2 retrospective studies, 3 case studies and 4 literature reviews. Conclusions: Coronectomy is an adequate preventative technique in protecting the inferior alveolar nerve, which is an alternative to the conventional extraction of third molars, which unlike the former technique, presents a high risk of injury to the inferior alveolar nerve. However, there is a need for new clinical studies, with a greater number of samples and with a longer follow-up period in order to detect potential adverse effects of the retained roots

Complications in the treatment with alveolar extraosseous distractors: literature review

  • Rodriguez Grandjean, Alfredo
  • Reininger, David
  • López Quiles, Juan
Background: To review the literature that analyses the types and frequency of complications associated with the use of extraosseous alveolar distraction from 2007 to 2013. Material and Methods: Review of the literature in PubMed, using these keywords; alveolar ridge, alveolar distraction osteogenesis, complication, literature review. Inclusion criteria were: articles published between 2007 and 2013 that included the distraction protocol, the complications encountered and the time when they occurred. Results: According to the above criteria, 12 articles were included in this review, where 334 extraosseous distractors were placed and 395 complications were encountered, of which 19 (4.81%) were intraoperative, 261 (66.07%) postoperative and 115 (29.11 %) were postdistraction. The most common complication was the incorrect distraction vector found in 105 cases (26.58%), in 23 cases (5.82%) there were severe complications, of which 14 (3.54%) were mandibular fracture and 9 (2.27%) were fractures of the distractor elements. Conclusions: According to this review, although alveolar distraction is a safe and predictable technique, it can cause complications; however, they are usually minor and easily resolved without affecting the treatment outcome.

Clinical and sociodemographic predictors of oral pain and eating problems among adult and senior Spaniards in the national survey performed in 2010

  • Montero Martín, Javier
  • Bravo Pérez, Manuel
  • López Valverde, Antonio
  • Llodra Calvo, Juan Carlos
Background: Pain and chewing difficulties have been identified as the strongest predictors of oral disadvantage. The aim of this study is to analyze and quantify the sociodemographic, behavioural and clinical factors modulating the oral pain and eating difficulties reported by Spanish adults and elderly Spanish people in the last National Oral Health Survey performed in 2010. Material and Methods: Data concerning pain and chewing difficulties were acquired on a Likert‑scale format from a representative sample of the Spanish general population with ages between 35-44 years (n=391) and 65 - 74 years (n=405). Risk factors were identified using bivariate analysis, after which the crude association between risk factors (sociodemographic, behavioural and clinical) and outcome variables (pain and eating problems) was assessed by adjusted odds ratios, calculated by means of multivariate logistic regression. Results: Eating problems and oral pain were mainly associated with prosthetic and caries treatment needs as clinical predictors, but female sex was also seen to be a relevant and significant risk factor for suffering pain and eating restrictions. Paradoxically, after taking into account all the aforementioned predictors, the adults had an almost two‑fold higher risk of reporting pain or eating difficulties than the elderly subjects. Conclusions: In agreement with the results from the last national oral health survey, prosthetic and caries treatment needs should be considered key factors in determining the oral well - being of the Spanish population. In sociodemographic terms, the women and adults were seen to be at a significantly higher risk of suffering pain and eating restrictions.

Evaluation of pretreatment serum interleukin-6 and tumour necrosis factor alpha as a potential biomarker for recurrence in patients with oral squamous cell carcinoma

  • Skrinjar, Ivana
  • Brailo, Vlaho
  • Vidovic Juras, Danica
  • Vucicevic Boras, Vanja
  • Milenovic, Aleksandar
Background: Oral squamous cell carcinoma (OSCC) constitutes 3 percent of all cancers with predominant occurrence in middle aged and elderly males. Tumour recurrence worsens disease prognosis and decreases quality of life in patients with OSCC. Proinflammatory cytokines such as interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) have been suggested to play a certain role in variety of tumours. The aim of this study was to investigate the relationship of pretreatment serum IL-6 and TNF-α levels on tumour recurrence in patients with OSCC in order to identify potential biomarkers for the early detection of disease recurrence. Material and Methods: The patients with newly diagnosed OSCC were treated and followed from the first visit from November 2006 until January 2008. Serum IL-6 and TNF-α concentrations were measured. The records of the patients were re-examined in July 2012 and data were recorded about cancer characteristics and tumour recurrence. Disease free survival was analyzed by Kaplan-Meier survival curves, log rank test and Cox proportional hazards regression. Results: Serum IL-6 was shown as an independent risk factor for tumour recurrence. Conclusions: Pretreatment serum IL-6 concentration may be a useful biomarker for identification of OSCC patients with increased risk of the disease recurrence.

Metallothionein immunoexpression in non-syndromic and syndromic keratocystic odontogenic tumour

  • Johann, Aline Cristina Batista Rodrigues
  • Carlos Caldeira, Patrícia
  • Caliari, Marcelo Vidigal
  • Gomez, Ricardo Santiago
  • Aguiar, Maria Cássia Ferreira
  • Mesquita, Ricardo Alves
Background: To commpare the metallothionein (MT) immunoexpression in non-syndromic and syndromic keratocystic odontogenic tumour (KOT), to correlate MT with cellular proliferation, and to evaluate the influence of inflammation in MT. Material and Methods: Fourteen cases of KOT were submitted to imm unohistochemistry for MT and Ki-67 analysis. The lesions were grouped according to their grade of inflammation, and statistical analysis was performed. Results: MT was higher in non-syndromic KOT than in syndromic KOT (p<0.05). No statistical difference in Ki- 67 could be identified; however, an inverse correlation was observed between MT and Ki-67 in both lesions. When analysing inflammation, non-syndromic KOT showed no differences in either MT or Ki-67. Conclusions: The MT imm unophenotype of syndromic KOT was different from non-syndromic KOT. MT might not be involved in the proliferation control of both KOT. MT and Ki-67 imm unoexp ressions proved to be unaffected by inflammation in non-syndromic KOT.

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