Intraoperative imaging in orbital reconstruction: how does it affect the position of the implant?

Intraoperative imaging enables the surgeon to control the position of the implant during orbital reconstruction. Although it might improve surgical outcome and avoid the need for revision surgery, it may also increase the duration of the operation and the exposure to radiation. The goal of this study was to find out whether intraoperative imaging improves the position of the implant in reconstructions of the orbital floor and medial wall. Two surgeons reconstructed complex orbital fractures in 10 cadavers. After the reconstruction a computed tomographic scan was made to confirm the position of the implant and, if required, to make any adjustments. Scans were repeated until the surgeon was satisfied. The ideal position was ascertained by scans that were obtained before and after creation of the fractures. The position of the implant achieved was compared with that of the ideal position of the implant, and improved significantly for yaw (p = 0.04) and roll (p = 0.03). A mean of 1.6 scans was required for each reconstruction (maximum n = 3). The main reason for alteration was the rotation roll. Intraoperative imaging significantly improves the position of the implant in fractures of the orbital floor and medial wall. The surgeon has quality control of its position during the reconstruction to restore the anatomical boundaries.     

What are the defining characteristics of the most cited publications in orthognathic surgery?

The purpose of this study was to identify the characteristics associated with highly cited papers in orthognathic surgery. This was a cohort study of articles published in the English-language literature from 1900 to 2017. Citation databases were searched for papers related to orthognathic surgery and the most frequently cited papers were identified. For each paper, the following variables were collected: region of origin, time-period of publication, corresponding author specialty, journal of publication, topic area, study design, and number of citations. The outcome variable was the citation index (citations per year). North American investigators published 70% of the 100 most-cited articles in orthognathic surgery. The majority of papers were from oral and maxillofacial surgeons. Frequent content areas were diagnosis, virtual planning, fixation/stability, and complications. The majority (54%) of studies were cohort or case report/series. The mean number of citations was 235.0 ± 126.5; the mean citation index was 9.9 ± 6.1 citations per year. Time-period, content area, and study design were associated with the citation index (all P < 0.001). Time-period, content area, and study design predicted the citation index (all P ≤ 0.009). Among frequently cited papers in orthognathic surgery, oral and maxillofacial surgeons had the highest volume of contributions. Diagnosis, treatment planning, and complications were the most common topics studied.     

What are the research priorities of Canadian dentists?

A joint CDA-Institutes of Musculoskeletal Health and Arthritis study was undertaken to evaluate the dental research priorities of Canadian dentists. A self-complete questionnaire was sent to all dentists in Canada with the December 2001 JCDA. This last article in a 3-part series presents the results on funding priorities. By April 1, 2002, 2,788 questionnaires, representing a response rate of approximately 16%, had been returned. Of 8 broad areas of research, respondents identified areas related to treatments as the most important: 77% cited the evaluation of the effectiveness of techniques and treatments as high priority, 76% the development of treatments and 70% the development of materials. The areas judged less important were improvements in access to care (42%) and a better understanding of patient behaviour (25%). With respect to more specific research topics, the highest priority subjects were dental materials other than amalgam and periodontal diseases.     

What are the effects of metopic synostosis on visual function?

Metopic synostosis is a premature fusion of the metopic cranial suture. Small case studies into the effects on vision have suggested that there is a raised incidence of astigmatic refractive error with increased risk of failure to develop normal vision if reconstructive surgery is delayed beyond 7 months of age. The aim of this study was to look at a much larger group of patients to give more statistical significance on the incidence of significant refractive error and strabismus in cases of metopic synostosis and compare this with that known for the general population of children at a similar age. A secondary objective was to look at the age at surgery and the visual outcome. A retrospective analysis of case notes was carried out for 64 children with a confirmed diagnosis of metopic synostosis attending the Oxford Craniofacial Unit. Twenty children (31%) were found to have a visual problem, with 18 needing glasses to correct a refractive error and 10 having strabismus. The nature of refractive error was generally hypermetropia, in some cases combined with low astigmatism (1.5 diopters [D] or less). Only 1 child was recorded as having more than 1.5 D of astigmatism. The age at surgery did not seem to influence visual outcome. The incidence of significant refractive error requiring correction and strabismus across the metopic group (31%) was higher than that found in the general population of children at a similar age (5%-11%). This reinforces the importance of orthoptic/ophthalmic surveillance in metopic synostosis.     

Does incorporating zinc in titanium implant surfaces influence osseointegration? A systematic review

Statement of problem

Titanium implant surfaces have been modified to improve osseointegration; however, the evidence for incorporating zinc into titanium implants to improve new bone formation and osseointegration is not clear.

What is the role of specialties in dentistry?

Dental specialties have an important, positive role in improving education and practice, stimulating research and defining quality expectations in their areas of expertise. However, it is well-known that general dental practitioners accomplish a significant portion of the dental therapy that commonly is classified as being within the scope of the respective recognized specialty areas. In this column, I have made suggestions about methods for improving the interaction between specialists and generalists and a call for better acceptance by each group of the capabilities of the other.     

What are the surgical risks and 2-year stability of mandibular anterior subapical osteotomy in the treatment of dentoalveolar protrusion?

Objective

To investigate the stability and complications of mandibular anterior subapical osteotomy (ASO) in the treatment of bimaxillary dentoalveolar protrusion by way of a retrospective study.

Materials and methods

One hundred and twenty patients who received orthognathic surgery at a single center between 2008 and 2017 were included. Relapse was assessed by serial tracings of lateral cephalograms which were obtained pre-operatively (T1), within 6 weeks after surgery (T2) and at 2 years after surgery. The changes between T2 and T3 represented stability and were tested using the paired t test. The relationship between the extents of surgical repositioning (T2–T1) and relapse (T3–T2) was investigated using the Pearson correlation coefficient. The associations between the variables and the occurrence of relapse and complications identified the risk factors and were evaluated using the χ² test or Fisher’s exact test. When r?>?0.80, clinical correlation was considered significant; and statistical significance was set at P?<?0.05, while confidence interval was set at 95%.

Results

There was a mean uprighting of L1-MP by 12.7°. At 2 years after surgery, 96.7% of the patients experienced a mean relapse of L1-MP by 2.9°. The extent of surgical repositioning was only weakly correlated with that of relapse and no specific factor that increased the risk of relapse could be identified. The most frequent complications were blood loss requiring transfusion, wound dehiscence or infection, gingival recession, and periodontal bone loss, involving 25.8 to 43.3% of the patients. The remaining complications included tooth root damage, fixation hardware exposure or infection, lingual mucosal laceration, and tooth devitalization. There were no cases of avascular necrosis or nonunion.

Conclusions

Although relapse occurred in most of the patients after 2 years, the actual extent was small (2.9°) which was not likely to be clinically significant.

Trial registration

HKUCTR-2964

Clinical relevance

Although ASO may be valuable in correcting mandibular dentoalveolar protrusion, the procedure brings with it risks and complications and should be reserved for severe deformities.