Predictores de dolor y tiempo de internación prolongado tras cirugía ortognática: estudio de cohorte retrospectivo / Predictors of pain and prolonged length of stay after orthognathic surgery: A retrospective cohort study

Introduction: Orthognathic treatment has assumed an important role in orthodontics and maxillofacial surgery in the last years; however, little has been investigated about this type of treatment. Objectives: The main purpose of this study was to identify major factors and/or predictors associated with postoperative pain (PP) and hospital length of stay (LOS) after orthognathic surgery. Materials and methods: 52 patients who underwent orthognathic surgery from 2008 to 2010 at the University Hospital of São Paulo University were investigated. Study variables such as patient characteristics, preoperative, intraoperative and postoperative data were collected. The outcome variables were PP and LOS. Descriptive and analytical statistics was computed for all variables. Results: 27.6% of patients had pain in the postoperative period. Lidocaine used in general anesthesia was an associated factor of PP. The overall mean LOS was 2 days; gender, location of procedure, type and duration of anesthesia were identified as probable predisposing factors. There was a significant correlation between anesthesia time and discharge. Anesthesia variables were more predictably related with postoperative pain and hospitalization time. Location of orthognathic procedure, however, was an important surgical variable that influenced in LOS. Conclusions: Intravenous lidocaine boluses used during general anesthesia were associated with PP. Male patients, single-jaw surgery, inhalational anesthesia and duration of anesthesia were predisposing factors that improve LOS.

Introducción: la cirurgía ortognática ha asumido un papel importante en la ortodoncia y en la cirugía maxilofacial en los últimos años. Sin embargo, se ha investigado poco sobre este tipo de tratamiento. Objetivos: el objetivo principal de este estudio fue identificar los principales factores o predictores asociados con el dolor posoperatorio (DP) y el tiempo de internación (TI) después de la cirugía ortognática. Materiales y métodos: fueron estudiados 52 pacientes que se sometieron a cirugía ortognática (2008 - 2010) en el Hospital Universitario de la Universidad de São Paulo. Se recolectaron variables de estudio tales como características de los pacientes y datos perioperatorios. Estadística descriptiva y analítica se calculó para todas las variables. Resultados: el 27,6% de los pacientes presentaron dolor en el posoperatorio. La lidocaína utilizada en la anestesia general fue un factor asociado del DP. El TI medio global fue de 2 días. El género, la localización del procedimiento, el tipo y la duración de la anestesia se identificaron como factores predisponentes probables. Hubo una correlación significativa entre el tiempo de anestesia y de descarga. Las variables de anestesia podían predecirse más cuando estaban relacionadas con el DP y el TI. La localización de la cirurgía ortognática, sin embargo, fue una variable quirúrgico importante que influyó en lo TI. Conclusiones: la lidocaína intravenosa en bolo utilizada durante la anestesia general se asoció con el DP. Los pacientes varones, la cirugía sobre una sola mandíbula, la anestesia inhalatoria y la duración de la anestesia fueron factores predisponentes que prolongaron el TI.

Bone healing of mandibular critical-size defects in spontaneously hypertensive rats.

Few articles have shown changes in bone metabolism caused by hypertension. The objective of this study was to investigate the relationship between hypertension and bone healing. Circular critical-size defects 5 mm and 2 mm in diameter were created, respectively, on the left and right side of the mandible in 40 spontaneously hypertensive and 40 control Wistar-Kyoto rats. Five animals from each strain were killed 2, 3, 5, 10, 15, 30, 60 and 90 days after surgery. The macroscopic evaluation showed great mandibular angle deformation on the left side and non-healed defects on both sides and groups. Histological evaluation revealed similar bone healing on both sides, with initial necrosis in the central area, and fibrosis and angiogenesis within the first 5 days. From the 10th postoperative day on, the newly formed bone displayed progressive thickening until the 90th postoperative day, when the defect margins presented a compact bone structure. Furthermore, the statistical analysis of the histometric data did not reveal any significant hypertension effect on bone healing in the defect area. These results suggest that bone healing was not different between spontaneously hypertensive rats and control rats.

Bone healing of mandibular critical-size defects in spontaneously hypertensive rats

Few articles have shown changes in bone metabolism caused by hypertension. The objective of this study was to investigate the relationship between hypertension and bone healing. Circular critical-size defects 5 mm and 2 mm in diameter were created, respectively, on the left and right side of the mandible in 40 spontaneously hypertensive and 40 control Wistar-Kyoto rats. Five animals from each strain were killed 2, 3, 5, 10, 15, 30, 60 and 90 days after surgery. The macroscopic evaluation showed great mandibular angle deformation on the left side and non-healed defects on both sides and groups. Histological evaluation revealed similar bone healing on both sides, with initial necrosis in the central area, and fibrosis and angiogenesis within the first 5 days. From the 10th postoperative day on, the newly formed bone displayed progressive thickening until the 90th postoperative day, when the defect margins presented a compact bone structure. Furthermore, the statistical analysis of the histometric data did not reveal any significant hypertension effect on bone healing in the defect area. These results suggest that bone healing was not different between spontaneously hypertensive rats and control rats.

Assessment of preclinical learning on oral surgery using three instructional strategies.

The purpose of this investigation was to evaluate three learning methods for teaching basic oral surgical skills. Thirty predoctoral dental students without any surgical knowledge or previous surgical experience were divided into three groups (n=10 each) according to instructional strategy: Group 1, active learning; Group 2, text reading only; and Group 3, text reading and video demonstration. After instruction, the apprentices were allowed to practice incision, dissection, and suture maneuvers in a bench learning model. During the students' performance, a structured practice evaluation test to account for correct or incorrect maneuvers was applied by trained observers. Evaluation tests were repeated after thirty and sixty days. Data from resulting scores between groups and periods were considered for statistical analysis (ANOVA and Tukey-Kramer) with a significant level of a=0.05. Results showed that the active learning group presented the significantly best learning outcomes related to immediate assimilation of surgical procedures compared to other groups. All groups' results were similar after sixty days of the first practice. Assessment tests were fundamental to evaluate teaching strategies and allowed theoretical and proficiency learning feedbacks. Repetition and interactive practice promoted retention of knowledge on basic oral surgical skills.

A novel approach to intraoral mandibular nerve anesthesia: changing reference planes in the Gow-Gates block technique.

PURPOSE: The Gow-Gates technique is said to have several advantages over traditional techniques to achieve mandibular nerve anesthesia; however, its routine use is quite limited, mainly due to complications during visual alignment of reference landmarks. The purpose of this study was to verify the validity and accuracy of a new method to reach the injection site. MATERIAL AND METHODS: Fifteen magnetic resonance images were captured. Distances from the ideal injection point in the condylar neck (puncture ideal) to the injection points located in the alpha and beta plane intersection (puncture Gow-Gates and puncture modified) were measured and compared. RESULTS: Positive and significant (P

Determinação dos planos de referência na técnica de anestesia mandibular de gow-gates: uma nova proposta / Assesment of reference planes in the Gow-Gates mandibular block: a new approach

A literatura é enfática na afirmação de que a técnica de anestesia mandibular proposta por Gow-Gates apresentaria uma série de vantagens sobre a técnica tradicional, como a menor necessidade de anestesia complementar e menores índices de aspiração e complicações. No entanto, o uso rotineiro da técnica de Gow-Gates tanto entre os clínico como entre os acadêmicos pode ser considerada ínfimo, e parte disto pode ser atribuído à dificuldade de identificação e compreensão dos planos de referência extra-orais. O intuito destes trabalho foi verificar a precisão e a validade de um novo método de determinação do local de puntura. Para este fim, obteve-se uma amostra de quinze imagens bilaterais da região das órbitas ao mento, capturadas por meio de ressonância magnética. Os pontos e planos geométricos de referência foram demarcados e traçados em computador...

The literature asseverates that the mandibular anesthesia technique described by Gow-Gates has several advantages than the traditional technique, such as lower requirement of supplementary injections and reduced incidence of positive blood aspiration and complications. However, rotine use of the Gow-Gates technique by clinicians and faculty can be considered negligible, whic may be attributed in some degree to problems in comprehension and identification of the extraoral reference planes. The purpose of this was to verify the precision and the validity of a new method to accomplish the injection site...