Florencio Monje

Effusion in Magnetic Resonance Imaging of the Temporomandibular Joint: A Study of 123 Joints

PURPOSE Effusion is the term used by radiologists for a hyperintensity signal seen inside a joint on magnetic resonance imaging (MRI). The aim of this study was to correlate the clinical and imaging features of this phenomenon, with the ultimate purpose of clarifying its meaning in dysfunctional processes of the temporomandibular joint (TMJ). PATIENTS AND METHODS The clinical histories of 111 patients (123 joints) with effusion on MRI were reviewed. Thirty-one patients (46 joints) with articular pathology but without effusion, chosen at randomized, served as a control group. Five clinical variables (articular pain, radiating pain, limited mouth opening, clicking, and clinical stage) and five imaging findings (disc displacement, effusion location, disc morphology, osteophytes, avascular necrosis, and osteochondritis dissecans) were evaluated. RESULTS Effusion in TMJ could be seen in relation to disc displacement and degenerative changes (osteophytes, avascular necrosis, osteochondritis dissecans). Clicking was more frequently found in TMJs without effusion. CONCLUSIONS These results suggest that effusion may be a marker of articular degeneration in the TMJ.

Hyperplasia of the Mandibular Condyle: Clinical, Histopathologic, and Treatment Considerations in a Series of 36 Patients

PURPOSE Mandibular condylar hyperplasia (CH) is a rare entity that causes overdevelopment of the mandible, creating functional and esthetic problems. The aim of this article was to describe demographic and clinical characteristics of CH, analyze histopathologic features and their association with scintigraphic and clinical findings, and evaluate esthetic and functional results after treatment by high condylectomy during the active phase. MATERIALS AND METHODS This retrospective study included 36 patients whose condyles were removed because of excessive unilateral growth resulting in facial asymmetry and occlusal disturbance. Of the 36 patients, 13 had had symptoms related to the temporomandibular joint, such as pain or clicking. In all the cases, high condylectomy was performed, and surgical specimens were sent for histologic examination and divided into 4 histologic types as described by Slootweg and Müller. Statistical analysis was performed by use of R software (version 2.10.1; R Foundation for Statistical Computing, Vienna, Austria) and SPSS software for Windows (version 15.0; SPSS, Chicago, IL) to evaluate our results. A χ(2) test was carried out to assess the possible association between gender and involved side. The association of histologic appearance with clinical symptoms was estimated by use of the Fisher exact test. An analysis of variance test was performed to evaluate a possible association between patient age and histologic type according to the Slootweg and Müller classification and between histologic type and uptake on bone single photon emission computed tomography (SPECT). RESULTS We could not find a relationship between histologic type and uptake of the affected condyle on bone SPECT or between age and histologic type. However, our statistical analysis revealed an association between histologic appearance and the presence of joint symptoms (P = .0049). Clinically, occlusion and facial symmetry improved in all patients postoperatively, and no recurrence was noted in any patient. Six patients required secondary surgery. CONCLUSION We could not find any significant association between age and histologic type or between bone SPECT and histologic type. However, a significant association between histologic type and temporomandibular joint symptoms was observed. High condylectomy combined with orthodontics achieved optimal esthetic and functional results and constituted the unique and definitive treatment in 30 of 36 patients.

Operative versus simple arthroscopic surgery for chronic closed lock of the temporomandibular joint: a clinical study of 344 arthroscopic procedures

Arthroscopic surgery has been reported to decrease pain in relation to the TMJ, improving maximal interincisal opening (MIO). The aim of the present study was to report the clinical outcome of arthroscopic surgery for the treatment of chronic closed lock (CCL) of the TMJ. Five hundred consecutive patients (670 joints) with TMJ derangement who underwent arthroscopy between 1995 and 2004 were retrospectively analysed. All were classified as II-V according to Wilkes. Within the series, various arthroscopic procedures were performed. The inclusion criteria for CCL of the TMJ were met by 257 patients (344 joints). The mean age was 30.24 years; 237 (92%) were female and 20 (8%) male. Mean preoperative visual analogue scale score for evaluation of TMJ pain was 53.21+/-23.02. Mean MIO was 24.75+/-4.89 mm. Following arthroscopy, a significant decrease in TMJ pain was achieved (p<0.0001). For MIO, mandibular protrusion and lateral excursion movements, a significant increase in mean values was observed following surgery (p<0.0001). No statistical differences were observed between arthroscopic lysis and lavage and operative arthroscopy in relation to postoperative pain or MIO at any stage of the follow-up period. Arthroscopy should be considered as a first-line treatment for CCL of the TMJ.

Alveolar split osteotomy for the treatment of the severe narrow ridge maxillary atrophy: a modified technique

Alveolar bone splitting and immediate implant placement have been proposed for patients with severe atrophy of the maxilla in the horizontal dimension. A new modification of the classical alveolar bone splitting for the treatment of the narrow ridge in the maxilla is provided. Thirty-three dental implants in eight consecutive patients were evaluated retrospectively following the described modified split-crest osteotomy. Inclusion criteria were: inadequate maxillary buccolingual dimension, 3-4mm of crestal width, and sufficient height from alveolar ridge tip to maxillary sinus floor. Primary stability was calculated using resonance frequency analysis (RFA). Alveolar bone height was measured in the panorex pre- and postoperatively. Histological bone examination was assessed following trephine bone harvesting during the second operation. Mean follow-up was 28.33 months. Bone regeneration of the inter-cortical gap occurred in 98% of implant sites (implant survival rate 100%). Mean implant stability quotient (ISQ) for the whole series of implants was 69.48. At the second operation, mean loss of the alveolar bone height was 0.542mm. Predictable results are obtained using the modified split-crest osteotomy. This technique provides an acceptable inter-cortical gap, decreases the risk of necrosis of the outer cortex, and provides a firm-wall box for the placement of particulate bone grafting.

Comparison between microcomputed tomography and cone‐beam computed tomography radiologic bone to assess atrophic posterior maxilla density and microarchitecture

PURPOSE The aim of this study was to analyze the relationship between bone density obtained by cone-beam computed tomography (CBCT) and morphometric parameters of bone analyzed by microcomputed tomography (μ-CT). MATERIAL AND METHODS An overall of 32 subjects ≤8 mm of bone height were included in the study. One site per patient was randomly selected to obtain bone core. Totally, 27 biopsies were available for μ-CT analysis. In addition, CBCT was taken after positioning a previously fabricated acrylic resin template with a 2-mm-diameter metal rod at the randomly selected implant site to study radiographic bone density (RBD). The relationship between μ-CT and CBCT quantitative variable and RBD was analyzed using Spearman correlation. RESULTS Positive correlations between BV/TV (r = 0.769, P < 0.001), BS/TV (r = 0.563, P = 0.002), Tb.Th (r = 0.491, P = 0.009), Tb.N (r = 0.518, P = 0.005) and vBMD (r = 0.699, P < 0.001) with RBD were identified. On the contrary, BS/BV (r = -0.509, P = 0.006), Tb.Sp (r = -0.539, P = 0.003) and Tb.Pf (r = -0.636, P < 0.001) were negatively correlated with RBD. Moreover, SMI (r = -0.380, P = 0.050) and DA (-0.245, P = 0.217) were negatively correlated but not statistically significant. CONCLUSION This study demonstrated the correlation between radiographic bone density (RBD) and bone density assessed by μ-CT. Therefore, our data supported the use of CBCT as pre-operative tool for implant treatment planning because it is shown to be reliable to assess atrophic posterior maxilla density and microarchitecture.

Changes in temporomandibular joint after mandibular subcondylar osteotomy: An experimental study in rats

The objective of this study was to analyze the changes in the different components of the temporomandibular joint and their relation with age after subcondylar osteotomy. For this purpose 149 Wistar rats were divided into three groups: osteotomy, sham operation, and control. Two experimental ages (30 and 70 days) and radiologic, morphometric, macroscopic, and histologic methods of analysis were used. Different changes were observed in young and adult animals. Subcondylar mandibular osteotomy in growing rats caused anteroinferior displacement of the temporal and mandibular component of the joint. At the end of the experimental period only condylar displacement was maintained. Other changes were flattening of the mandibular condyle, which was transient, and lateral thickening of the articular disc. Subcondylar mandibular osteotomy in adult rats caused slight anterior displacement of the joint components at the end of the experimental period. At this age, although changes similar to those in growing animals were observed in some cases, in other cases the presence of pathologic findings, such as deformation of the condylar cartilage, thickening of the disc, intra-articular adherences, and osteolysis of the temporal fossa, were observed. Changes in the joint components were more marked in growing rats than in adults. In growing rats they affected the form of the condylar process to a greater extent, but the majority of these changes were transient. In adult rats, alterations in the joints were less pronounced, but they affected a greater number of joint components and were permanent.

The rare phenomenon of vascular pedicle ossification of free fibular flap in mandibular reconstruction

Ossification of the vascular pedicle in the vascularized free fibular flap (VFFF) has been only previously described twice for jaw reconstruction. A case of severe trismus secondary to periosteal osteogenesis following VFFF for maxillary reconstruction, and four cases of ossification of the vascular pedicle in VFFF for maxillary and mandibular reconstruction have been respectively described. Etiology remains unclear, although presence of periosteum in continuity with bone seems to play a major role. Hormonal stimuli, stress over the bone, and corticosteroid therapy have been proposed as determinant factors, although no clear correlation has been already established. No histologic studies concerning the generation of new bone around the vascular pedicle in VFFF are nowadays present. We report a new case of vascular pedicle ossification of VFFF following mandibular reconstruction, this being the third report in the literature, and focus on histologic examination of the specimen.

Mandibular lesion as the first evidence of multiple myeloma: case report

Plasma cell dyscrasias affect the jaws relatively infrequently, and on rare occasions this is the first sign of the disease. This article describes the case of a patient aged 53 who presented with a lytic lesion in the right mandible which was initially diagnosed as an ameloblastoma. The diagnosis was made histopathologically and further investigation showed that the patient had multiple myelomatosis.

Maxillary Sinus Lateral Wall Thickness and Morphologic Patterns in the Atrophic Posterior Maxilla

BACKGROUND The aim of the present study is to examine the sinus lateral wall thickness (LWT) of atrophic posterior maxilla (<10 mm) of patients with complete and partial edentulism and determine the influence of residual ridge height (RH), sex, and age on maxillary LWT. METHODS Four hundred fourteen measures were taken from 140 consecutive patients that met the inclusion criteria. On the selected sagittal section, a built-in digital caliper recorded in millimeters the RH and LWT (a perpendicular line at 3, 5, 7, 10, 13, and 15 mm from the lowest point of the sinus floor). Edentulous spans were further classified as complete edentulous atrophic maxilla (CEM) and partial edentulous atrophic maxilla (PEM). The mixed linear model was used to test the effects of sex, type of edentulism, edentulous span, and RH on the measurement of the LWT of the sinus. RESULTS Mean LWT for PEM was 1.71 ± 0.12 mm, and for CEM, 1.57 ± 0.07 mm (P = 0.01). The mixed model yielded significant effect of edentulous span (P = 0.048) and interactions among type of edentulism and edentulous span (P <0.001) and edentulous span by RH (P <0.01). Age and RH were positively associated with LWT; however, they did not interact with RH, sex, or type of edentulism. RH has been shown to correlate with edentulous span (P <0.001) and type of edentulism (P = 0.01). The longer the edentulous span, the thinner the LWT. Similarly, RH was larger for PEM (6.85 ± 0.34 mm) than CEM (5.69 ± 0.26 mm). CONCLUSIONS The maxillary sinus lateral wall tends to increase in thickness from the second premolar to the second molar and from 5 mm up to 15 mm. In addition, RH, presence of teeth adjacent to the edentulous atrophic ridge, and age were shown to influence maxillary sinus LWT.

Reliability of Four Zygomatic Implant-Supported Prostheses for the Rehabilitation of the Atrophic Maxilla: A Systematic Review

PURPOSE The reliability of oral rehabilitation by four zygomatic implants with no anterior support remains to be determined. The aim of this systematic review was to assess the predictability of this approach in regard to implant survival, technical and biologic complications, and quality of life. MATERIALS AND METHODS An electronic literature search was conducted from September 2000 to November 2013. Human clinical trials in which oral rehabilitation was achieved by the use of four zygomatic implants with no additional placement of standard implants were included. The primary outcome was the survival rate of the zygomatic implants. In addition, random effects meta-analyses of the selected studies were applied to avoid potential bias caused by methodologic differences among studies. RESULTS Zygomatic implant survival rate weighted mean (WM) was 96.7% (range, 95.8% to 99.9%), with a 95% confidence interval (CI) of 92.5% to 98.5%. Only a limited number of surgical complications were reported, with orbital perforation the most significant. Similar results were obtained for prosthetic complications (few occurrences). Additionally, patient satisfaction levels were shown to be high, approaching that of the general population. CONCLUSION Data from the present systematic review suggest that maxillary rehabilitation by four zygomatic implants with no anterior support is a reliable approach.