José María Martínez-González

Melatonin stimulates the growth of new bone around implants in the tibia of rabbits

Abstract:  This study evaluated the effect of the topical application of melatonin in accelerating bone formation associated with implants 2 months after their application to the tibiae of rabbits. Twenty New Zealand rabbits were used. Twenty implants treated with melatonin and 20 control implants without melatonin were placed in the proximal metaphyseal area of each tibia. Studies of new bone formation were subsequently made at 15, 30, 45 and 60 days. Cortical width and cortical length of new bone formation were measured. Following implantation, an anteroposterior and lateral radiologic study was carried out. Collected samples were sectioned at 5 μm and stained using hematoxylin–eosin, Masson’s trichromic and Gordon‐Switt reticulin stains. After a 60 day treatment period, melatonin increased the length of cortical bone (95.13 ± 0.42%) versus that around control implants (62.91 ± 1.45%). Related to the perimeter of cortical bone of the tibiae, melatonin induced new bone 88.35 ± 1.56% versus 60.20 ± 1.67% in the control implants. Melatonin regenerated the width and length of cortical bone around implants in tibiae of rabbits more quickly than around control implants without the addition of melatonin.

Crestal bone loss evaluation in osseotite expanded platform implants: a 5‐year study

OBJECTIVE The aim of this prospective clinical study was to evaluate the survival rates at 5 years of expanded platform implants placed in the anterior zone of the maxilla and immediately restored with single crowns. MATERIALS AND METHODS Implants incorporating the platform-switching concept were placed in fresh extraction sockets in the maxillary arch, with each patient receiving a provisional restoration immediately after implant placement. After 15 days, final screwed restorations were inserted. Mesial and distal bone heights were evaluated using digital radiography on the day following implant placement and at 1, 3, 6, 9, 12, 24, 36 months and 5 years. Primary stability was measured with resonance frequency analysis (RFA) using the Osstell Mentor device. Sixty-four implants were placed in 32 men and 32 women ranging in age between 29 and 60 (mean: 39.64 ± 5.16 years). RESULTS Mean mesial bone loss was 0.08 mm (SD 0.42). Mean distal bone loss was 0.14 mm (SD 0.56). Over the course of the 5 years, the mean RFA value was 72.5 ± 3.1 SD. CONCLUSION The platform-switched implants remained stable over the course of 5 years and had an overall survival rate of 97.1%.

Meta-analysis of the increase in height in maxillary sinus elevations with osteotome

Objectives: To compare the different variations of sinus elevation techniques with osteotomes, to evaluate the increase in height achieved, and to quantify the osseointegration periods and the success rates for the implants placed. Study Design: A meta-analytic study with descriptive statistics was carried out on sinus elevations using osteotomes, analyzing a total of 11 articles published between the years 2003 and 2008. Results: Summers’ classic technique for performing sinus elevations with osteotomes differs from the current techniques being used with respect to the use of drills, the manner in which the sinus floor is fractured and how the sinus membrane is lifted, and especially on the type of graft used—the most current tendency being not to use a graft. The maximum gain in height is 4.62 mm, and the minimum gain in height is 2.07 mm, starting with a maximum residual bone height of 8.8 mm and a minimum of 4.1 mm. The osseointegration period is 4.9 months and the success rate is 95.5%. Conclusions: Performing sinus elevations with osteotomes is a predictable technique that enables achieving an increase in bone height and successful results, similar to those of other techniques used, in the placement of implants. Key words:Osteotomes, maxillary sinus elevation, dental implants, osseointegration.

Glossopharyngeal Neuralgia: A Presentation of 14 Cases

OBJECTIVE The aim of this study was to present a series of clinical cases on glossopharyngeal neuralgia as well as the therapeutic approach used. PATIENTS AND METHODS This observational, descriptive, and retrospective study was carried out on 14 patients who were diagnosed with glossopharyngeal neuralgia between the years 1997 and 2007 at the Oral-Facial and Implant Surgery Department and at the Otorhinolaryngology, Neurology, and Neurosurgery Departments of the Madrid University Hospital. RESULTS The study consisted of 8 women and 6 men. The neuralgia was found predominantly on the left side, and considering the 4 areas of topographical distribution into which the distribution of the ninth nerve is divided, the results of our study showed that the maximum of the areas affected was 3, with 2 areas being the most common. Accompanying symptoms were only recorded in 4 of the cases. In 12 of the cases, initial treatment was with prescription drugs consisting of different doses of carbamazepine. In the remaining cases, or once the other course of treatment was proven to be unsuccessful, surgical treatment was used, applying different techniques and obtaining a high rate of success with them. CONCLUSIONS Glossopharyngeal neuralgia is an uncommon pathology that is treated with medicine or surgery, with carbamazepine and vascular microdecompression being the treatments of choice.

Evaluation of the anaesthetic properties and tolerance of 1:100,000 articaine versus 1:100,000 lidocaine. A comparative study in surgery of the lower third molar

Objectives: To evaluate the anaesthetic properties and tolerance of articaine versus lidocaine at equal vasoconstrictor concentration. Study Design: A total of 96 male and female patients who underwent surgical treatment of the lower third molar participated. Patients were randomly assigned to articaine hydrochloride with epinephrine 1:100,000 and lidocaine hydrochloride with epinephrine 1:100,000. The variables analysed were latency period, duration of anaesthetic effect, tolerance and adverse reactions. Results: Both the latency period and the duration of anaesthetic effect were greater for articaine, although the differences were not statistically significant. Latency: mean difference of 2.70 ± 2.12 minutes (95%CI of -1.51 minutes - 6.92 minutes). Duration: mean difference of -33 minutes 5 seconds ± 31 minutes (95% CI -1 hour 35 minutes - 29 minutes). There were 4 adverse events that did not require the patients to be withdrawn from the study. Conclusions: The anaesthetics in this study have very similar properties for use in surgery and have demonstrated a good safety and tolerability profile Key words: Articaine, lidocaine, vasoconstrictor, adverse reactions.

Impact of prosthetic rehabilitation type on satisfaction of completely edentulous patients. A 5-year prospective study

Abstract Objective. The aim of this study was to evaluate the satisfaction of rehabilitated edentulous patients in relation to implant prosthetic type. Materials and methods. This prospective cohort study included 40 completely edentulous patients wearing conventional prostheses. They were divided into two study groups: Group A contained 20 patients rehabilitated with implant-supported fixed prostheses and Group B contained 20 patients with overdentures. Subjects were evaluated by means of a specially designed questionnaire before treatment and after 1, 3 and 5 years. Results. Group A exhibited better results in terms of esthetics, function and personal satisfaction, although without statistically significant differences. However, statistically significant differences were found within parameters of oral hygiene after 1 year in favor of Group B. Conclusions. Overall satisfaction was seen to increase after implant rehabilitation, regardless of the type of prosthesis used. The satisfaction of edentulous patients differs depending on prosthetic type. Patients rehabilitated with fixed prostheses obtain a generally higher level of satisfaction than patients wearing overdentures.

Biological response to porcine xenograft implants: an experimental study in rabbits

Purpose: The aim of this study was to evaluate the effect of a new porcine biomaterial and collagen paste in 20 New Zealand rabbits. Materials and Methods: Forty implants using a porcine xenograft made up of 80% corticocancellous collagenated bone particles of ⩽300 &mgr;m in size were placed in the proximal metaphyseal area of both tibiae. Four periods of time were formed: 1h, 5, 8, and 15 months. After implantation, an anteroposterior and lateral radiological study was carried out. Samples were sectioned at 5 &mgr;m and stained using hematoxylin-eosin, Massons trichromic, and Gordon-Switt reticulin stains. Results: These results confirmed the biocompatibility of this porcine biomaterial-collagen paste; only a few, occasional macrophages and scattered lymphocytes were observed. No fibrosis was observed between the implants and the bone. Moreover, the material was osteoconductive acting as a “scaffold” for bone cells, and there was a progressive increase in bone growth in and around the implants. Conclusion: This new porcine biomaterial-collagen paste seemed to be biocompatible, bioresorbable, and osteoconductive.

Dental considerations in diagnosis of maxillary sinus carcinoma

BACKGROUND Maxillary sinus carcinoma is a rare entity with an incidence of 0.2% and a low patient survival rate due to the frequency of late diagnosis. METHODS In this multicenter, transversal, retrospective, observational study, the authors analyzed patients who had received a diagnosis of maxillary sinus carcinoma, registering their oral symptoms, histologic type, treatment efficacy, and survival rate. RESULTS Maxillary sinus carcinoma was diagnosed in 24 patients (15 men and 9 women), of which 75% were squamous cell carcinomas. All patients had dental mobility, and some had swelling, orosinus fistula, or some dental loss. Mean patient survival rate was 38.83 months. CONCLUSIONS A history of pain or swelling of unknown origin, an unexplained widening of periodontal ligament space, or mobility of the teeth should be considered warning signs of maxillary sinus carcinoma. PRACTICAL IMPLICATIONS Recognition of oral symptoms by the dentist would help in making an early diagnosis of maxillary sinus carcinoma, improving the patients chances of survival and quality of life.

Comparison of peri-implant soft tissues in submerged versus transmucosal healing: A split mouth prospective immunohistochemical study

OBJECTIVE The present split-mouth prospective study involves an immunohistochemical evaluation of peri-implant soft tissue healing after the osseointegration period, comparing submerged and transmucosal approaches using two-piece implant systems. The null hypothesis was that both surgical procedures elicit a similar immune response of the peri-implant soft tissues. DESIGN Thirty-one healthy patients were included in this study, in which two implants were placed in the right and left maxillary pre-molar regions. A total of 62 dental implants were analyzed, establishing a control side with 31 submerged implants, and a study side with 31 exposed implants bearing healing abutments. After a three-month healing period, a soft tissue biopsy was collected and prepared for immunohistochemical analysis of the proportions of different lymphocyte subpopulations. RESULTS The comparative analysis between the submerged and transmucosal approaches failed to identify statistically significant differences in CD19+ B cells, CD4+ T cells, CD8+ T cells, CD25+ T cells or γd T cells. However, significant differences in NK lymphocytes (p = 0.012) were recorded with the submerged surgical procedure. CONCLUSIONS Peri-implant soft tissue immune response with submerged or transmucosal healing protocols demonstrated comparable outcomes after the osseointegration period. There is sufficient evidence that the null hypothesis of no difference cannot be rejected. To the best of our knowledge, this is the first study of its kind. Further research is therefore needed to further clarify the role of these lymphocyte subpopulations in peri-implant soft tissues.

Complications in the treatment of mandibular condylar fractures: Surgical versus conservative treatment

OBJECTIVES In the present article, we aim to review the main intra- and post-operative complications associated with two different therapeutic approaches for treating mandibular condylar fractures: conservative (CTR) and surgical treatment (ORIF, Open Reduction and Internal Fixation). MATERIAL AND METHODS We have carried out a retrospective, meta-analytic, observational study using literature review, covering the period between 2000- September 2017. The data obtained were processed using statistical software SPSS v.0.18 and R v.2.11.1. The chi-squared test was used for comparison of relative frequencies for independent samples. RESULTS A total of 2458 patients with 2810 fractures were collected for study. Patients treated with CTR and ORIF were an average of 29 years old, of those treated with CTR, 72.37% and 27.63% were male or female respectively and, of those treated with ORIF, 70.36% and 29.64% were male or female respectively. The main complications suffered by CTR and ORIF patients were: asymmetry (10.2%/6.4%), residual pain (6.5%/5.6%), temporomandibular joint and articular imbalance (15.9%/10.3%) and malocclusion (11.1%/4.0%), respectively. We only found significant differences between CTR and ORIF in the number of cases of temporomandibular joint and articular imbalance and malocclusion. Facial nerve damage was found exclusively among ORIF patients (8.6%) of which 8.3% were temporary and 0.3% permanent. CONCLUSIONS The complications associated with either technique are minimal and infrequent, resulting in successful outcomes with minimal morbidity. CTR are associated with complications deriving from delayed mobilization leading to functional limitation, whereas the main complication associated with ORIF treatment was facial nerve damage.