Patient-specific distractors for customized mandibular distraction osteogenesis to relieve upper airway obstruction in infants with Pierre Robin sequence.

The purpose of this article is to report the author's technique for using patient-specific distractors for customized distraction osteogenesis of the mandible in patients with Pierre Robin sequence and upper airway obstruction. The advantages of virtual planning and patient-specific plates in other aspects of craniomaxillofacial surgery, such as orthognathic and reconstructive surgery, have been reported previously. Similar to patient-specific plates, the theorized advantages of patient-specific distractors in infants with Robin sequence and upper airway obstruction include increased accuracy, decreased operating time, and less morbidity to vital anatomic structures such as the inferior alveolar nerve and developing tooth buds. This technique is novel in using patient-specific distractors in the craniomaxillofacial skeleton.

Does a learning curve exist for accuracy in three-dimensional planning for maxillary positioning in bimaxillary orthognathic surgery?

The purpose of this study was to investigate the influence of time, and experience, on the accuracy of maxillary repositioning in bimaxillary orthognathic surgery performed using virtual surgical planning (VSP). Patients who had undergone bimaxillary orthognathic surgery were reviewed. Maxillary position on pre- and postoperative computed tomography scans was compared. The patients were divided into groups according to the year in which VSP was performed and surgery completed. Linear distances between upper jaw reference landmarks were measured in all three planes of space to determine accuracy between the preoperative VSP and the surgical outcome at various time points. One hundred subjects met the eligibility criteria for assessment and were allocated to groups: 2013 (n=10), 2014 (n=17), 2015 (n=39), 2016 (n=20), and 2017 (n=14). Overall, the results demonstrated improved precision in maxillary position over the years, with more accurate results in patients who underwent surgery in 2015, 2016, and 2017. Mean linear differences between planned and obtained results demonstrated more accurate results in the horizontal direction, followed by transverse and vertical directions. An overall average difference within 1mm was observed for 51.3% of the measurements included in the sample group. Time, and surgeon experience, can influence the accuracy of maxillary positioning in bimaxillary orthognathic surgery.

Medial canthopexy using transcaruncular barb and miniplate: technique and cadaver study.

Traditional medial canthopexy techniques require transnasal access, periorbital skin incision, and/or direct canthal suturing, often yielding unpredictable outcomes. The transcaruncular canthal barb and miniplate technique is a simplified method of canthopexy that avoids these manoeuvres. 10 transcaruncular medial canthopexies were performed on cadavers with simulated naso-orbito-ethmoid (NOE) injury. Differences in mean pre-injury and post-canthopexy intercanthal distance (ICD) and palpebral aperture width (PAW) measurements were compared using a matched paired t test. Reliability between pre-injury and post-injury intercanthal distance and PAW was compared with intraclass correlation coefficients. Canalicular distortion and final implant position were assessed with post-canthopexy computed tomography (CT). There was no difference in mean palpebral aperture width (32.32 and 32.43 mm) or mean intercanthal distance (29.18 and 29.06 mm) between pre-injury and post-canthopexy groups (both p>0.05). All intercanthal distance and PAW intraclass correlation coefficients were >0.97 (p<0.05). Post-canthopexy, CT scans showed canaliculus distortion in 4/10 of upper and 0/10 of lower canaliculi with all canthal barbs in the correct position relative to the plate. In a cadaver telecanthus model, medial canthopexy using the transcaruncular barb and miniplate technique reliably reduces the medial canthus and did not distort the lower lacrimal canaliculus, but may distort the upper canaliculus.

Gun orientation in self-inflicted craniomaxillofacial gunshot wounds: risk factors associated with fatality.

The purpose of this study was to evaluate whether orientation of a firearm predicts survival, and to identify risk factors associated with fatality in subjects with self-inflicted craniomaxillofacial gunshot wounds. A retrospective cohort study design was used. The primary predictor variable was orientation of the weapon, defined as in the coronal (lateral) or sagittal (anterior-posterior) trajectory pattern. The primary outcome variable was death for subjects on arrival or during their hospital stay. Other covariates measured include demographic, firearm-related, and psychosocial variables. Risk factors for fatality were identified using multivariate logistic regression. Of the 92 subjects that met study inclusion criteria, 47 (67.2) held the firearm in the coronal position. In the full multivariate model, coronal gun orientation (OR=7.7, 95% CI: 2.0, 30.1, p=0.003) and the absence of a psychiatric diagnosis were associated with an increased risk of fatality (OR=0.1, 95% CI: 0.04, 0.5, p=0.002). Coronal firearm orientation was associated with an increased risk of fatality following self-inflicted craniomaxillofacial gunshot injuries. A patient with a documented psychiatric disorder was not found to be more likely to succumb to this type of injury.

Sialolithiasis in a residual Wharton's duct after excision of a submandibular salivary gland.

Treatment of salivary stones includes both surgical and non-surgical techniques. Surgical approaches range from excision of the sialolith, for those near the duct orifice, to removal of the affected salivary gland and its associated duct, for stones near the hilum of the gland. We present a case of two sialoliths triggering an acute infection in a residual Wharton's duct, 12 years after the removal of the associated submandibular gland. Excision of the sialoliths and treatment of the infected duct via sialodochoplasty was successfully performed in this patient. If the Wharton's duct is not removed with the associated submandibular gland, the potential for infection and continuous growth of dormant calcifications exists. We also address the aetiology, pathogenesis, and management of patients with sialolithiasis in the absence of a major salivary gland.