An Analysis of Frequency, Morphology, and Locations of Maxillary Sinus Septa Using Cone Beam Computed Tomography

PURPOSE

To evaluate the frequency, morphology, and locations of maxillary sinus septa using cone beam computed tomographic (CBCT) imaging of the entire maxillary sinus and to analyze factors influencing the presence or absence of septa.

MATERIALS AND METHODS

CBCT images of the maxilla taken during a 1-year study period (October 1, 2012, to September 30, 2013) were evaluated for the presence and type of septa as well as the health or pathology of the maxillary sinus. Differences in age, gender, type of dentition, septa location, and sinus pathology with regard to the incidence of sinus septa were analyzed statistically.

RESULTS

The study included 294 maxillary sinuses in 212 patients (126 women and 86 men) with a mean age of 53.8 years. Sinus septa were present in 141 patients (66.5%) and in 166 of 294 sinuses (56.5%). The most common orientation of the septa was coronal (61.8%), 7.6% were oriented axially, and 3.6% were aligned sagittally. Most septa were located on the floor of the maxillary sinus (58.6%), commonly (60.7%) in the region of the first and second molars. The maxillary sinuses were diagnosed in 36.4% of cases as healthy and without thickening of the sinus membrane. Sex was a significant variable in the health of the maxillary sinus; 57.7% of the sinuses in women and 72.3% in men were diagnosed as pathologic.

CONCLUSION

Septa are common anatomical structures and are most often found in the first or second molar region on the floor of the maxillary sinus. To prevent possible complications during sinus floor elevation procedures, a thorough three-dimensional radiographic examination of the sinus prior to surgery is recommended.

Influence of hemostatic agents upon the outcome of periapical surgery: dressings with anesthetic and vasoconstrictor or aluminum chloride

OBJECTIVE

To evaluate the effects of different hemostatic agents upon the outcome of periapical surgery.

DESIGN

A retrospective study was made of patients subjected to periapical surgery between 2006-2009 with the ultrasound technique and using MTA as retrograde filler material. We included patients with a minimum follow-up of 12 months, divided into two groups according to the hemostatic agent used: A) dressings impregnated in anesthetic solution with adrenalin; or B) aluminum chloride paste (Expasyl). Radiological controls were made after 6 and 12 months, and on the last visit. The global evolution scale proposed by von Arx and Kurt (1999) was used to establish the outcome of periapical surgery.

RESULTS

A total of 96 patients (42 males and 54 females) with a mean age of 40.7 years were included. There were 50 patients in the aluminum chloride group and 46 patients in the anesthetic solution with vasoconstrictor group. No significant differences were observed between the two groups in terms of outcome after 12 months - the success rate being 58.6% and 61.7% in the anesthetic solution with vasoconstrictor and aluminum chloride groups, respectively (p > 0.05).

CONCLUSION

The outcome after 12 months of follow-up was better in the aluminum chloride group than in the anesthetic solution with vasoconstrictor group, though the difference was not significant.

Implant periapical lesion: diagnosis and treatment

The implant periapical lesion is the infectious-inflammatory process of the tissues surrounding the implant apex. It may be caused by different factors: contamination of the implant surface, overheating of bone during drilling, preparation of a longer implant bed than the implant itself, and pre-existing bone disease. Diagnosis is achieved by studying the presence of symptoms and signs such us pain, swelling, suppuration or fistula; in the radiograph an implant periapical radiolucency may appear. A diagnostic classification is proposed to establish the stage of the lesion, and determine the best treatment option accordingly. The following stages are distinguished: acute apical periimplantitis (non-suppurated and suppurated) and subcacute (or suppurated-fistulized) apical periimplantitis. The most adequate treatment of this pathology in the acute stage and in the subacute stage if there is no loss of implant stability is apical surgery. In the subacute stage, if there is implant mobility, the extraction of the implant is necessary.

Key words:Implant periapical lesion, apical periimplantitis, retrograde periimplantitis.

Survival of implants placed with the osteotome technique: an update

A literature review is made to analyze the survival of implants placed with the osteotome technique. A PubMed search was made based on the key words "osteotome AND dental implants", corresponding to publications between 1998-2008. The inclusion criteria were: a) a minimum of 10 patients; b) a minimum follow-up of 6 months; c) implants placed using the osteotome technique with or without indirect sinus lift; and d) specification of the implant number and survival rate. Sixty-four articles were identified, of which 20 met the inclusion criteria. A total of 2006 implants were placed in 1312 patients using the osteotome technique. The duration of follow-up after prosthetic loading ranged from 6-144 months. Indirect sinus lift was carried out in all but one of the studies. The residual crest height ranged from 2.8-12 mm, with a mean gain in bone after sinus lift of 2.5-5.1 mm. The time from implant placement to prosthetic loading varied from 1.5-9 months. The percentage implant survival rate was 85.1-100%. The survival rate of implants placed with the osteotome technique is high and does not differ with respect to implant placement with the conventional technique.

Pain and swelling after periapical surgery related to the hemostatic agent used: anesthetic solution with vasoconstrictor or aluminum chloride

OBJECTIVE

To assess pain and swelling in the first 7 days after periapical surgery and their relationship with the agent used for bleeding control.

STUDY DESIGN

A prospective study was conducted between October 2006 and March 2009. Patients subjected to root surgery, who completed the questionnaire and who consented to the postoperative instructions were included in the study. The subjects were divided into two groups according to the hemostatic agent used: A) gauze impregnated with anesthetic solution with vasoconstrictor; or B) aluminum chloride. The patients were administered a questionnaire, and were asked to record the severity of their pain and swelling on a plain horizontal visual analog scale (VAS). Data were recorded by the patients on the first 7 postoperative days. In addition, the patients were asked to record analgesic consumption.

RESULTS

A total of 76 questionnaires (34 in group A and 42 in group B) were taken to be correctly completed. Pain was reported to be most intense two hours after surgery. At this point 52.6% of the patients had no pain. Seventy-five percent of the patients consumed analgesics in the first 24 hours. There were no significant differences between the two groups in terms of the intensity of pain or in the consumption of analgesics. Swelling reached its maximum peak on the second day; at this point, 60.6% of the patients suffered mild or moderate swelling. The Expasyl group showed significantly greater swelling than the gauzes group.

CONCLUSION

The type of hemostatic agent used did not influence either the degree of pain or the need for analgesia among the patients in this study. However, the patients belonging to the Expasyl group suffered greater swelling than the patients treated with gauzes impregnated with anesthetic solution with vasoconstrictor.

Peripheral giant cell granuloma associated with dental implants: clinical case and literature review

Peripheral giant cell granuloma (PGCG) associated to dental implants is a very infrequent peri-implant soft-tissue complication, with only 11 cases recorded in the literature to date. The present study describes a 54-year-old woman presenting a swelling of the alveolar margin in the fourth quadrant in relation to a fixed prosthesis cemented over implants. Treatment consisted of complete resection of the lesion with implantoplasty of the exposed implant threads. The diagnosis of PGCG was confirmed by histological study, and no relapse has been recorded after 12 months of follow-up.

Comparison of immediate and delayed implants in the maxillary molar region: a retrospective study of 123 implants

PURPOSE

The purpose of this study was to compare marginal bone loss and success rates 1 year after implants had been placed in maxillary molar sites, either immediately postextraction or after the extraction sites had healed (delayed).

MATERIALS AND METHODS

A retrospective case study was made of subjects treated with immediate or delayed dental implants in the maxillary molar region between January 2006 and December 2008. A protocol was prepared in which patient age, sex, implant length and diameter, type of prosthesis, buccal plate width, and use of bone grafting were recorded. After 12 months, data relating to the clinical and radiologic conditions of the implants and the success rate according to the criteria of Buser et al were recorded. The variables were analyzed statistically (Student t test, Pearson correlation, Games-Howell test).

RESULTS

The study included 123 implants placed in 70 patients; 35 implants were immediate and 88 were delayed. Two immediate and six delayed implants failed, resulting in success rates of 94.3% and 93.2%, respectively. Average marginal bone loss was 0.56 mm for immediate implants and 0.67 mm for delayed implants.

CONCLUSIONS

The placement of immediate implants in maxillary molar sites achieved similar results to implants placed in healed sites in the same region after 12 months. No statistically significant differences were found between implant survival rates or average marginal bone loss.

A retrospective comparison of 1,022 implants: immediate versus nonimmediate

PURPOSE

The aim of this study was to compare the survival of implants placed in mature bone with the survival of implants placed in fresh extraction sockets in the same patients.

MATERIALS AND METHODS

A retrospective study of patients treated simultaneously with at least one immediate and one nonimmediate implant was carried out for the period 2005 to 2008. Data were recorded for patient age and sex; implant length, diameter, and position; and, for postextraction implants, distance between the implant and the alveolar bone.

RESULTS

One thousand twenty-two implants were placed in 150 patients; 480 were placed immediately and 542 were placed in mature bone. The mean implant survival rate was 93.4%; survival rates were 93.8% for immediate implants and 93.2% for nonimmediate implants. The failure rate in the maxilla was 5.2% and in the mandible it was 2.8%. The failure rate for immediate implants in the posterior maxilla was 8.5%, which was statistically significantly higher than for implants placed elsewhere. Of the failed implants, 72% were early failures.

CONCLUSIONS

The survival rate of implants placed in fresh extraction sockets was similar to that of implants placed in mature bone. A statistically significantly higher failure rate was seen with immediate implants placed in the posterior maxilla.

A prospective clinical study of polycarboxylate cement in periapical surgery

OBJECTIVE

To evaluate the clinical efficacy of polycarboxylate cement as retrograde filling material.

DESIGN

A prospective clinical study was made of 25 patients subjected to periapical surgery with ultrasound and magnifying loupes, in which polycarboxylate cement was used as retrograde filling material. Measurements were made of the area and diameter of the lesions pre- and postoperatively, and 6 and 12 months after the operation. The apical resection and retrograde filling areas were also measured, and the prognosis following surgery was recorded.

RESULTS

A total of 23 patients with 31 apicoectomized teeth were studied (2 patients being lost to follow-up). The mean area of the periapical lesions before surgery was 52.25 mm2, with a mean major diameter of 6.1 mm and a mean lesser diameter of 4.8 mm. The success rate after 12 months was 54.7%, according to the criteria of Von Arx and Kurt. The prognosis was poorer in females, in larger lesions, and in cases with larger retrograde filling areas.

CONCLUSIONS

Polycarboxylate cement offers good results, with important bone regeneration after periapical surgery.

Virtual articulator for the analysis of dental occlusion: an update

The future of dental practice is closely linked to the utilization of computer-based technology, specifically virtual reality, which allows the dental surgeon to simulate true life situations in patients. The virtual articulator has been designed for the exhaustive analysis of static and dynamic occlusion, with the purpose of substituting mechanical articulators and avoiding their errors. These tools will help both odontologists and dental prosthetists to provide the best individualized treatment for each patient. The present review analyzes the studies published in the literature on the design, functioning and applications of virtual articulators. A Medline-PubMed search was made of dental journals, with the identification of 137 articles, of which 16 were finally selected. The virtual articulator can simulate the specific masticatory movement of the patient. During mandibular animation, the program calculates the sites where the opposing teeth come into contact. The studies made to assess the reliability of the virtual articulator show good correspondence in visualization of the number and position of the dynamic contacts. The virtual articulator is a precise tool for the full analysis of occlusion in a real patient.

Key words: Virtual articulator, dental occlusion, dental articulator.

Radiographic findings in the maxillary sinus: comparison of panoramic radiography with computed tomography

PURPOSE

To assess the prevalence of radiographic signs of maxillary sinus pathology in patients undergoing dental implant treatment and to compare the efficacy of panoramic radiography, computed tomography (CT), and three-dimensional (3D) CT with Implametric software in the diagnosis of sinus pathology.

MATERIALS AND METHODS

Thirty patients were selected at random from those being treatment-planned to receive implant-supported restorations in the maxilla and who had a panoramic radiograph, a conventional CT scan in acetate, and a 3D CT scan in digital format. The radiographic maxillary sinus findings were categorized as: (1) no sign of pathology, (2) mucosal thickening, (3) mucous cyst, or (4) occupation of the entire sinus.

RESULTS

Seventeen women and 13 men were included, with a mean age of 50.9 years. There was a 38.3% prevalence of radiographic abnormalities (23.3% mucosal thickenings, 10% mucous cysts, and 5% occupation of the entire sinus). Of the 23 sinuses that displayed radiographic signs of pathology, only 1 (4.3%) was correctly diagnosed by the panoramic radiograph.

CONCLUSIONS

The most common radiographic maxillary sinus finding was mucosal thickening, followed by mucous cysts and occupation of the whole sinus. Conventional CT can be considered a reliable method for the diagnosis of maxillary sinus pathology.

Maxillary sinus septa: a systematic review

This review analyzes articles published on the presence of septa in maxillary sinuses. An automated search was conducted on PubMed using different key words. This search resulted in 11 papers in which the presence of antral septa was assessed. These septa are barriers of cortical bone that arise from the floor or from the walls of the sinus and may even divide the sinus into two or more cavities. They may originate during maxillary development and tooth growth, in which case they are known as primary septa; or they may be acquired structures resulting from the pneumatization of maxillary sinus after tooth loss, in which case they are called secondary septa. Several methods have been used in their study, direct observation on dried skulls or during sinus lift procedures; and radiographic observation using panoramic radiographs or computed tomographs. Between 13 and 35.3% of maxillary sinuses have septa. They can be located in any region of the maxillary sinus and their size can vary between 2.5 and 12.7 mm in mean length. Some authors have reported a higher prevalence of septa in atrophic edentulous areas than in non-atrophic ones. If a sinus lift is conducted in the presence of maxillary sinus septa, it may be necessary to modify the design of the lateral window in order to avoid fracturing the septa.

Oromandibular dystonia: a dental approach

Oromandibular dystonia consists of prolonged spasms of contraction of the muscles of the mouth and jaw. Primary idiopathic forms and secondary forms exist. Secondary dystonia develops due to environmental factors; some cases of cranial dystonia after dental procedure have been reported, but the causal relationship between these procedures and dystonia remains unclear. Traumatic situations in the mouth, such as poor aligned dentures or multiple teeth extractions may cause an impairment of proprioception of the oral cavity, leading to subsequent development of dystonia. The clinical characteristics of oromandibular dystonia are classified according to the affected muscles. The muscles involved may be the muscles of mastication, muscles of facial expression, or the muscles of the tongue. At present, there is no known cure for OMD. The mainstay of treatment for most focal dystonia is botulinum toxin injections. It is important for the dentist to be familiar with oromandibular dystonia, as it can develop after dental treatment and is often misdiagnosed as a dental problem.

Augmentation procedures for deficient edentulous ridges, using onlay autologous grafts: an update

The purpose of this review was to analyze publications related to augmentation procedures using autologous onlay grafts and to evaluate the survival/success rates of implants placed in the augmented areas. An automated search was made in Medline, of clinical publications from 2002 to 2007, including at least 5 patients and with a minimum follow-up of 6 months. Ten papers were included. These suggested that grafts are indicated when the height of the alveolar crest is less than 5mm, or the width less than 4mm. The surface resorption of grafts protected by guided bone regeneration membranes was less than for unprotected grafts. Calvarial grafts suffered less resorption than did iliac grafts. The healing period of the graft until implant placement was, in most cases, 4-6 months. The most frequent complications in the recipient site were wound dehiscences. Prosthetic loading time was, in almost all patients, 3 months after implant placement. Implant survival rate ranged from 97.1% to 100%. Although , due to the difficulty in finding homogenous studies, the sample is small, we can conclude that autologous onlay block bone grafts are an effective procedure for alveolar crest augmentation; graft surface resorption is reduced when the grafts are protected by regeneration membranes; few complications arise from the procedure; and the success rate for implants placed in the reconstructed area is between 89.5 and 95.7%.