Histomorphometric evaluation of guided bone regeneration around implants with SLA surface: an experimental study in beagle dogs.

The aim of this study was to evaluate the efficacy of collagen membranes, either alone or combined with a human demineralized freeze-dried bone allograft (DFDBA) or natural bovine bone graft, in bone defects around dental implants with an SLA (sand-blasted, large grit, acid-etched) surface. The experiments were carried out in three beagle dogs using a split-mouth design. On one side of the jaw, three implants were placed and intra-bony defects were created and covered with a collagen membrane, randomly combined in two of the defects with human DFDBA or inorganic bovine bone graft. A control implant, without membrane covering or defect filling, was also placed. On the other side of the jaw, three implants were placed and the bone defects were treated in a similar fashion, but without membrane covering. The studied variables were the percentage of bone-to-implant contact within the limits of the initial bony defect and percentage of the original bony defect occupied by bone tissue. Although no statistically significant differences were found in this study between the membrane and nonmembrane groups, bone defects augmented with anorganic bovine bone and membranes showed the most promising results from a histological and histomorphometric perspective.

Clinical comparison of dexketoprofen trometamol and dipyrone in postoperative dental pain.

A total of 125 outpatients with moderate to severe pain after surgical removal of one impacted third molar were randomly assigned to receive dexketoprofen trometamol 12.5 or 25 mg or dipyrone 575 mg. For first-dose assessments, patients rated their pain intensity and its relief at regular intervals. From 60 min post dose to the end of the 6-h observation period, both doses of dexketoprofen trometamol had higher pain relief scores than dipyrone: Between 3 and 6 h the differences were statistically significant. In addition, peak measures (PIDmax and PARmax) were statistically superior after both doses of dexketoprofen trometamol compared to dipyrone. The overall efficacy assessed at the end of the first-dose phase was rated as good or excellent by 90%, 83.3%, and 70% of patients receiving dexketoprofen trometamol 25 mg, dexketoprofen trometamol 12.5 mg, and dipyrone, respectively. The number of patients who required remedication during the 6-h period was significantly lower in both dexketoprofen groups. Repeated-dose data were also obtained. No significant differences were found in the efficacy after repeated doses, the number of doses taken, or the mean time elapsed between doses. The overall efficacy at the end of the repeated-dose phase was rated as good or excellent by 84.2%, 66.7%, and 70% of patients receiving dexketoprofen trometamol 25 mg, dexketoprofen trometamol 12.5 mg, and dipyrone, respectively. The frequency of adverse events was similar for all treatments and no serious adverse events were reported during the study.

Optic nerve blindness following a malar fracture.

Optic nerve blindness following a malar fracture is an uncommon and usually permanent complication. When the loss of vision is immediate and total, the prognosis is poor. The case of a patient who suffered immediate and complete loss of vision after a malar fracture is presented. Computed tomography revealed compression of the optic nerve by bony fragments. No improvement was observed after megadose steroids and surgical treatment. The incidence, pathogenesis, diagnostic approach and therapeutic possibilities are discussed and the importance of establishing precisely the moment of the loss of vision is stressed.

Bone regeneration after radicular cyst removal with and without guided bone regeneration.

In order to determine the degree of bone regeneration after removal of radicular cysts using guided bone regeneration (GBR), a prospective, controlled and randomized clinical study was performed. Thirty patients with radicular cysts were divided into three groups. One group, the control group (n=10 patients), was treated by enucleation and primary closure. The other two groups were treated by enucleation and primary closure but GBR was used in addition, using a resorbable membrane (n=10) and a nonresorbable membrane (n=10). The membranes were fixed with nonresorbable Memfix System screws. The residual volume and the density of the newly formed tissue was measured by computer-assisted tomography and computer-assisted digital image analysis before enucleation and three and six months postoperatively. No statistical significance was found in density and residual volume between the three treatment groups after six months. These results suggest that GBR using membranes does not contribute to increased bone regeneration.

Tissue regeneration in bone defects adjacent to endosseous implants: an experimental pilot study.

Extraction socket defects or alveolar ridge defects may limit or restrict placement of implants. The present study assessed the efficacy of inducing bone formation with demineralized freeze-dried bone (DFDB), osteoinduction with hydroxyapatite (HA), and guided bone regeneration with expanded polytetrafluoroethylene (e-PTFE) in bone defects adjacent to endosseous implants in an animal model. Twenty-four implants were placed in the long bones of 3 pigs. After preparation of 24 cylindric acute defects adjacent to the coronal 5 mm of each implant, 18 of the defects were treated by DFDB, HA, or e-PTFE. The 6 remaining defects healed spontaneously with no treatment (controls). In each pig, one tibia received 4 commercially pure titanium screw implants (3.75 mm x 15 mm), while the contralateral tibia received 4 HA-coated cylindric implants (3.25 mm x 15 mm). Bone formation in response to the 3 treatments and control cases was evaluated using computer-assisted densitometric image analysis. The results showed that a higher density of tissue formed under e-PTFE membranes. A significantly greater increase in bone density was noticed in bone defects treated with an e-PTFE membrane vs DFDB (P = 0.04), in e-PTFE vs control sites (P = 0.04), and in defects treated with HA vs DFDB (P = 0.04) in HA-coated implants. In titanium implants the differences observed were not significant. It was also observed that bone regeneration in defects treated with HA differs with the type of implant used (titanium vs HA-coated implants), but such differences were not significant.

Granular-cell tumours: an immunohistochemical study.

The granular cell tumour (myoblastoma, Abrikosoff's tumour) and the congenital epulis in newborns (Neumann tumour) are two lesions rarely found in the oral cavity, whose histogenetic origin is highly controversial. This work analyses using immunohistochemical techniques 15 cases of myoblastomas and two of congenital epulis with different mono- and poly-clonal antibodies. Positive immunostaining was found for S-100 protein and neuron-specific enolase in all the cases of myoblastoma, and for vimentin and carcinoembryonic antigen in some cases. No immunoreactivity was observed for any of the other 13 antibodies used in congenital epulis.

Atypical histiocytic granuloma of the tongue: case report.

Primary malignant lymphomas of the tongue have rarely been described, and reported cases are usually related to the posterior part of the tongue which is rich in lymphoid tissue, forming part of Waldeyer's ring. Making a distinction between pseudolymphoma and malignant lymphoma is important. Pseudolymphoma is a benign lesion not requiring aggressive therapy. Several lesions in the oral cavity, including atypical histiocytic granuloma, angiolymphoid hyperplasia with eosinophilia, and traumatic ulcerative granuloma with stromal eosinophilia have been described as having certain microscopic features similar to those of pseudolymphoma. Atypical histiocytic granuloma is not associated with systemic disease or dissemination and heals spontaneously despite its microscopic appearance.

Central epithelial odontogenic ghost cell tumour. A case report.

Central epithelial odontogenic ghost cell tumour, a neoplastic variant of calcifying odontogenic cyst, is a rare lesion with a very few cases published in the English literature. Histologically, the tumour consists of clusters of infiltrating odontogenic epithelium and ghost cells in varying numbers. We describe the first case of central epithelial odontogenic ghost cell tumour occurring in a pregnant woman and in which determination of bone densitometry in the preoperative panoramic radiographs has been performed. We have reviewed the literature available in English and compared it with our case.

Adenomatoid odontogenic tumor arising in a dental cyst: report of unusual case.

The case of an adenomatoid odontogenic tumor developing over a dentigerous cyst is reported. A 12-year-old boy was referred by his pediatric dentist to the service of Oral and Maxillofacial Surgery of the Asturias Central Hospital (Spain) for evaluation of a radiolucent image compatible with a dentigerous cyst. Microscopic examination revealed the presence of an adenomatoid odontogenic tumor located over the linear epithelium of a dentigerous cyst. Based on the literature, the clinico-pathological, diagnostic, radiological and therapeutic characteristics of the case are commented in detail.

Ameloblastic fibroma: a case report in a 6 year old.

A six-year-old boy was seen by his dentist for a tumor mass in the left mandibular region. The panograph revealed a multilocular radiotransparent lesion extending from the canine to the left mandibular ascending ramus with well defined borders. After biopsy, the lesion was enucleated via curettage of the bone bed. The lesion was diagnosed as ameloblastic fibroma. After six months, radiographs showed that the surgical defect had filled with new bone.

Oral squamous cell carcinoma of the mandibular region: A survival study.

BACKGROUND: Oral squamous cell carcinomas (SCC) of the mandibular region present the lowest survival rates of the whole oral cavity. The purpose of this analysis was to evaluate the prognostic significance of several diagnostic and therapeutic variables in the survival rates of these carcinomas. METHODS: Forty-nine patients with oral cancers were treated by primary site surgery, involving mandibular resection in all cases. Thirty-one patients underwent postoperative adjuvant radiotherapy. RESULTS: Overall mean survival time and 5-year survival rate were 56.5 months and 44%, respectively. Patients in stages III and IV showed a statistically significant (p = .01) lower survival rate than those in stage II, and positive surgical margins had an adverse effect on survival (p = .03). No differences were found between patients treated by marginal or segmental mandibulectomy. CONCLUSIONS: Among the prognostic predictors studied, only the status of the surgical resection margin (odds ratio, 5.7) and tumor stage (III and IV vs II showed odds ratios of 2.1 and 3.6, respectively) affected the prognosis for SCC of the mandibular region. Tumor site was not associated with prognosis but was related with the probability that surgical margins were involved.

Pleomorphic adenoma of the salivary glands: prospective clinicopathologic and flow cytometric study.

BACKGROUND: Primary surgery is the appropriate treatment for most pleomorphic adenomas of the salivary glands. However, no reliable criteria have been established to predict tumors with aggressive features. METHODS: In 44 patients treated for salivary pleomorphic adenoma, clinicopathologic features and flow cytometric findings were recorded. S-phase fractions were classified as low (0%-1%), intermediate (1.1%-5%), and high (>5%). The relationship between clinicopathologic parameters and flow cytometric DNA analysis was assessed with the Pearson's correlation coefficient. RESULTS: The mean tumor size was 24.4 mm. Microscopically, myxoid structures predominated in 61.4% of cases. Only five specimens showed high S-phase fractions. All samples were DNA diploid (mean coefficient of variation 3.2%). S-phase fraction and tumor size correlated significantly (r = 0.73, P = 0.003). Two patients with recurrent tumors had high S-phase fractions both on the first resected specimens and at the time of the second operation. CONCLUSIONS: The S-phase fraction may be a valuable predictor of aggressive behavior in salivary pleomorphic adenomas. High S-phase fractions were associated with higher tumor size and a greater tendency to recur.

[Clinical criteria for calculating the risk of malignancy in leukoplastic lesions]. / Criterios clínicos para calcular el riesgo de malignización de la lesión leucoplásica.

We have studied 74 patients with leukoplasia to establish clinical and aetiological criterias. We wanted the criterias to permit us to have a guide line and follow them before and after their treatment.

Heterotopic brain tissue in the oral cavity.

A most rare phenomenon of heterotopic brain in the soft palate, containing elements of choroid plexus, is presented. The principal theories regarding the pathogenesis of this malformation are presented and discussed. Its most frequent sites, the treatment to be followed, and the nomenclature to be employed in this type of lesion are also analyzed.

[Early diagnosis of periodontal disease]. / Diagnostico precoz de la enfermedad periodontal.

Early diagnosis is necessary if the prevalence of periodontal disease is to be brought under control. For periodontal screening in dental practice we propose to employ the C.P.I.T.N. system, combined with examination of two or four dental bite-wing radiographs. Both of these procedures can be accurately applied in general dental practice conditions. The screening is not time consuming and can yield very important diagnostic data.

[Epidemiological study of periodontal disease in an Oviedo school population]. / Estudio epidemiológico de patología periodontal en la población escolar de Oviedo.

1,276 young people, between 6-20 years old, representing the urban school population from Oviedo (Spain) were evaluated by the Community Periodontal Index of Treatment Needs (C.P.I.T.N.). From this population: 1. 66.1% were found to have bleeding on probing, without evidence of attachment loss (gingivitis), or presence of local irritants. This population represented a treatment need of improving oral hygiene. 2. 29.6% had moderate attachment loss (probing pocket depths between 4-5 mm.) and/or presence of local irritants. They were determined to need scaling and root planing. 3. 0.7% had probing pocket depths higher than 6 mm., which requires a more complex specialized type of therapy. Based on these treatment needs, the number of treatment hours was determined, estimating that it would be necessary to spend 1649 hrs. to diagnose and treat this detected periodontal conditions. 93% of this time could be provided by dental auxiliary personnel. The therapeutic needs were higher in males and clearly augmented with age.

Right atrial outlet atresia with straddling left atrioventricular valve. A form of double outlet atrium.

We present three hearts showing right atrial outlet atresia with straddling left atrioventricular valve; clinical data of two of the patients are reported. For semantic and practical reasons we believe the terms tricuspid or mitral atresia should not be used in these cases, and atrial outlet atresia is preferable; for similar reasons we prefer to use stradding left or right atrioventricular valve. These anomalies represent an interesting form of double outlet atrium and diagnosis clinically may be possible if the existence of the anomaly is considered. Differentiation from common atrioventricular canal with atrial outlet atresia is important since total repair, which is possible for this last anomaly, does not seem feasible in cases like ours. Classifications of tricuspid atresia may have to be enlarged to include cases with double outlet from either ventricular chamber or anatomically corrected malposition. Characterisation of the right ventricular chamber is difficult; we believe that description of its morphology and the type and mode of its connections should be used.