Roger William Fernandes Moreira

Complications of intraoral donor site for bone grafting prior to implant placement.

Purpose:The purpose of this prospective study was to evaluate the morbidity and the major complications of intraoral donor sites for bone grafting prior to implant placement. Materials:The records of 104 consecutive patients with indication for bone grafting prior to implant installation treated at Piracicaba Dental School by the Department of Oral and Maxillofacial Surgery, from June 2001 until June 2003, were reviewed. Results:One hundred three surgical procedures were realized, in which 40% were harvested from mandibular symphysis, 28.8% from mandibular ramus, and 31.2% from maxillary tuberosity. Prevalence of complications among intraoral donor sites was more significant after harvestingvesting the mandibular symphysis. The major complication and discomfort reported by the patients was sensory deficit in lower lip and mental area. It was noted that 16% harvesting procedures involving symphysis and 8.3% involving the mandibular ramus area reported some sensory deficit. No complications were found involving the maxillary tuberosity. Conclusion:Complications and morbidity were smaller in the ramus than in symphysis, and temporary sensory disturbances were the most common complications, noted in both symphysis and ramus areas.

Influence of Diameter and Length of Implant on Early Dental Implant Failure

PURPOSE To relate diameter and length of implants with early implant failure. PATIENTS AND METHODS Implants with a cylindrical design and surface treatment by removal of titanium via acidification from 3 different manufacturers were used in this study. Two surgical procedures for submerged implants were evaluated--the placement of the implants (first surgical phase) and the procedure for reopening (second surgical phase)--before the installation of the prosthetic system. The length of the implants was classified as short (6-9 mm), medium (10-12 mm), or long (13-18 mm), and the diameter was classified as narrow, regular, or wide. The statistics were computed with SAS statistical software (SAS Institute, Cary, NC). Step-wise and chi(2) analyses were used, in addition to univariate and multivariate logistic regression. RESULTS In this retrospective study, 1,649 implants (807 maxillary and 821 mandibular) were placed in 650 patients (mean age, 42.7 years) in different areas: anterior maxilla (458), posterior maxilla (349), anterior mandible (270), and posterior mandible (551). The early survival rate for all 1,649 implants was 96.2%. Regarding diameter, the largest loss was observed in narrow implants (5.1%), followed by regular (3.8%) and wide (2.7%) implants. Regarding length, the largest loss was observed in short implants (9.9%), followed by long (3.4%) and medium (3.0%) implants. Early loss occurred in 50 implants, 31 (4.3%) of which were installed in anterior areas and 19 (2.8%) in posterior areas. According to step-wise analyses and the chi(2) test, short implant (P = .0018) and anterior installation of implant (P = .0013) showed associations with early loss. CONCLUSION A significant relationship of early implant loss was observed with short implants. No relationships between early loss of implants and the osseous quality or diameter of implants were observed. These findings may be attributed to the operators experience with different implant designs, learning curves, or changes in technique and indications for the use of short implants from 1996 to 2004.

The Influence of Tobacco on Early Dental Implant Failure

PURPOSE The purpose of this study was to assess tobacco use as a risk factor for early implant failure. MATERIALS AND METHODS To address the research aim, a retrospective study design was used, and a study sample was derived from among patients who had 1 or more implants inserted between July 1996 and July 2004. The main predictor variable was the frequency of tobacco use. The major outcome variable was early implant failure. Appropriate descriptive, bivariate, and multivariate statistics were computed. RESULTS The study sample was composed of 650 patients who had 1,628 implants inserted and were selected for analysis. The early implant loss rates found in the nonsmoking group and the smoking group were 3.32% and 2.81%, respectively. Univariate and bivariate analyses showed no statistical significance for early implant losses associated with the frequency of tobacco use. CONCLUSIONS The results of this study suggest that tobacco use alone cannot be considered as a factor for risk related to early implant failures. Prospective studies are needed to assess the risk of early implant failure in conjunction with smoking.

Histological and histomorphometric analyses of calcium phosphate cement in rabbit calvaria

PURPOSE To assess bone regeneration in critical sized defects in the rabbit calvarium, filled with the bone substitute calcium phosphate cement. MATERIAL AND METHODS Circular bone defects (8mm) were made in both parietal bones of 10 rabbits. One of the defects was filled with the calcium phosphate cement, and the other received autogenous bone harvested from the calvaria. The animals were killed at 3 or 6 weeks (n=5). Data analysis included qualitative assessment of the calvarial specimens and histomorphometric analysis was used to quantify the amount of new bone within the defects. RESULTS The microscopic analysis of the samples showed bone healing with both calcium phosphate cement and autogenous bone graft. Data obtained from the histomorphometric analysis were statistically analyzed using 2-way analysis of variance and the Tukeys test. Data analysis showed that the autogenous bone graft had significantly more new bone compared with calcium phosphate cement at 3 and 6 weeks. Calcium phosphate cement at 6 weeks presented similar results to autogenous bone at 3 weeks. Both treatments presented an increase in bone healing with time. CONCLUSION Treatments allowed bone regeneration that increased with time, however surgical cavities treated with the autogenous graft had more bone formation than those with calcium phosphate cement.

A Comparison of Motorcycle and Bicycle Accidents in Oral and Maxillofacial Trauma

PURPOSE The aim of this study was to present a large series of motorcycle- and bicycle-related traumas to the face in an attempt to identify the injury pattern in motorcyclists and bicyclists. PATIENTS AND METHODS Data were collected from patients during a 10-year period (1999 through 2009), which included demographic data, diagnosis of facial fractures, use of protective devices, dentoalveolar trauma, and facial soft tissue injuries. RESULTS There were 556 patients with bicycle accidents and 367 with motorcycle accidents. Men were involved in 79% (436) of bicycles accidents and 82% (299) of motorcycle accidents. Young male patients were more frequent in bicycle and motorcycle accidents. Two hundred fifty bicyclists showed 311 maxillofacial fractures. Two hundred twenty-one motorcyclists showed 338 maxillofacial fractures. Motorcycle accidents caused multiple fractures in more patients. Seventy-six percent of motorcyclists were using helmets at the time of the accidents, whereas 6% of cyclists were using helmets. Motorcyclists showed a larger number of lacerations, whereas bicyclists showed a larger number of abrasions. Avulsion was the most common dentoalveolar injury for these accident types. Hospital stays were 3.8 days for motorcyclists and 1.3 days for bicyclists. CONCLUSIONS The high-impact collisions typically observed in motorcycle accidents is directly related to larger percentages of soft tissue lacerations and facial fractures. The low-impact trauma that is observed in bicycle accidents is more commonly associated with soft tissue abrasion, hematoma, and dentoalveolar fractures. This stresses the need for compulsory legislation for helmet use with face-guards for cyclists and motorcyclists. It is important to take measures to alert the public regarding the severity of injuries likely to occur in bicycle- and motorcycle-related accidents and ways to prevent them.

A 9-Year Retrospective Study of Dental Trauma in Piracicaba and Neighboring Regions in the State of São Paulo, Brazil

PURPOSE The purpose of this study was to evaluate the occurrence of dentoalveolar trauma during a 9-year period in the Oral and Maxillofacial Surgery Division at Piracicaba Dental School, State University of Campinas in patients from the Piracicaba municipality and neighborhood regions in São Paulo, Brazil. PATIENTS AND METHODS This retrospective epidemiologic study from January 1999 to December 2007 evaluated all patients who presented at the Oral and Maxillofacial Surgery Division at Piracicaba Dental School with sustained oral and maxillofacial traumatic injuries associated with dentoalveolar trauma. Information regarding age, gender, etiology, use of protective devices such seatbelts, crash helmets, and presence of facial fractures and general trauma, oral condition, stage of dentition, date of trauma, drug abuse, type, teeth affected, and classification of the trauma were gathered from the medical files. Descriptive analysis was conducted. RESULTS In total, 2,785 patients were analyzed and 542 (19.46%) were included in this study. The male to female ratio was 2.81:1. Most patients presented with oral hygiene as regular (51.85%). Friday, Saturday, and Sunday were the most prevalent days. Smoking was the most common harmful habit analyzed (16.05%) followed by alcohol use (15.87%). Bicycle accidents (26.94%) were the most common cause, followed by falls (22.69%). With regard to protective devices, 31.51% of drivers were wearing seatbelts during the accidents and helmets were used by 84.38% of motorcycle drivers at the moment of injury. One hundred thirty-five facial fractures were associated with dental and dentoalveolar traumas, and the mandible was the facial bone most associated with dentoalveolar trauma. Upper and lower limbs were most frequently associated with general trauma, accounting for 140 (38.78%) and 111 (30.75%), respectively. CONCLUSION This study shows that dentoalveolar trauma rates and patterns in the Piracicaba municipality and neighborhood regions in São Paulo are similar to other populations. The weekend is the period with the major incidence of dentoalveolar trauma. Alcohol consumption was linked with this type of trauma. Dentoalveolar trauma is involved in and closely related to severe maxillofacial trauma. The use of a helmet is as important as that of a seatbelt. More studies are necessary for a better knowledge and understanding when considering protocols and organization charts in emergency rooms.

Traumatic intrusion of maxillary permanent incisors into the nasal cavity: report of a case.

Complete intrusion injuries in the mixed or permanent dentition are relatively rare and represent one of the most serious injuries to the periodontal ligament in dental traumatology. This paper describes the case history of a 7-year-old boy who sustained displacement of central incisors into the nasal cavity. Surgical repositioning was undertaken and a splint was placed.

Mechanical and photoelastic analysis of four different fixation methods for mandibular body fractures

OBJECTIVE The aim of the present study was to compare four methods of fixation in mandibular body fractures. STUDY DESIGN Mechanical and photoelastic tests were performed using polyurethane and photoelastic resin mandibles, respectively. The study groups contained the following: (I), two miniplates of 2.0 mm; (II) one 2.0 mm plate and an Erich arch bar; (III) one 2.4 mm plate and an Erich arch bar, and (IV) one 2.0 mm plate and one 2.4 mm plate. The differences between the mean values were analyzed using Tukeys test, the Mann-Whitney test and the Bonferroni correction. RESULTS Group II recorded the lowest resistance, followed by groups I, IV and III. The photoelastic test confirmed the increase of tension in group II. CONCLUSION The 2.4 mm system board in linear mandibular body fractures provided more resistance and the use of only one 2.0 mm plate in the central area of the mandible created higher tension.

Clinical, radiographic, and histological analyses of calcium phosphate cement as filling material in maxillary sinus lift surgery

BACKGROUND The installation of dental implants in the posterior maxilla is often faced with resorbed alveolar processes, resulting from a combination of pneumatization of the maxillary sinus, the effects of periodontal disease, and physiological bone resorption. The sinus lift surgery has been practiced since 1980 with the aim to increase bone height in this region for an implant supported prosthetic rehabilitation, and various filling materials have been used for such. OBJECTIVES This study aimed to clinically, radiographically, and histologically evaluate a preparation of calcium phosphate cement (Bone Source(®), BS) used as filling material in maxillary sinus elevation surgery. METHODS Ten patients were operated requiring maxillary sinus graft for future placement of osseointegrated implants. After a period ranging from 9 to 16 months, a clinical evaluation and biopsy of the grafted area in the region adjacent to the axis of the implant to be inserted were performed. RESULTS Clinically and radiographically, no evidence of resorption/substitution of BS was noticed. Although no patients have had postoperative complications and the material presented fully biocompatible characteristics with woven bone in intimate contact with BS, it was not possible to place any implants due to minimal bone formation and friability of the material. CONCLUSION It was concluded that despite the osteoconductive capacity of BS, this conventional calcium phosphate preparation does not support sufficient amount of new bone formation that could allow its use as filling material for maxillary sinus floor lift and subsequent dental implant placement.

Development plates for stable internal fixation: Study of mechanical resistance in simulated fractures of the mandibular condyle

OBJECTIVE To develop Y-shaped plates with different thicknesses to be used in simulated fractures of the mandibular condyle. Ten plates were developed in Y shape, containing eight holes, and 30 synthetic polyurethane mandible replicas were developed for the study. MATERIAL AND METHODS The load test was performed on an Instron Model 4411 universal testing machine, applying load in the mediolateral and anterior-posterior positions on the head of the condyle. Two-way ANOVA with Tukey testing with a 5% significance level was used. RESULTS It was observed that when the load was applied in the medial-lateral plate of greater thickness (1.5 mm), it gave the highest strength, while in the anteroposterior direction, the plate with the highest resistance was of the lesser thickness (0.6 mm). A plate with a thickness of 1.5 mm was the one with the highest average value for all displacements. In the anteroposterior direction, the highest values of resistance were seen in the displacement of 15 mm. CONCLUSION After comparing the values of the biomechanical testing found in the scientific literature, it is suggested that the use of Y plates are suitable for use in subcondylar fractures within the limitations of the study.