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In the past, maxillomandibular advancement has resulted in considerable improvement in the volume of the posterior airway space. The objective of the present study was to find out how mandibular advancement without maxillary involvement would affect the posterior airway space in patients with mandibular retrognathism. Cone-beam computed tomographic (CT) scans were done for 20 patients before, and six months after, mandibular advancement. Cephalometric analysis at both time points included 2-dimensional and 3-dimensional assessment of the upper airway. Eight men and 12 women presented a preoperative mean (SD) Wits value of 7.4 (1.54) mm, with an airway area of 7.11 (1.88) cm2 and a volume of 14.92 (4.46) cm3. Six months postoperatively they showed a Wits value of 2.7 (0.41) mm, an airway area of 11.33 (3.49) cm2, and a volume of 25.7 (6.10) cm3. There was a mean (range) enlargement of 59 (22-82) % of the area and 73 (29-108) % of the volume. A preoperative Wits value of 8mm or more correlated significantly with a larger increase of the posterior airway space (p=0.002). At the same time, an improvement in the Wits value of 4.5mm or more correlated significantly with an increase in volume (p=0.016). The effect of mandibular advancement on the posterior airway space was significant, and the volumetric effect seems to be even more relevant than the two-dimensional changes.

The influence of dose reductions on diagnostic quality using a series of high-resolution ultralow-dose computed tomography (CT) scans for computer-assisted planning and surgery including the most recent iterative reconstruction algorithms was evaluated and compared with the fracture detectability of a standard cranial emergency protocol. A human cadaver head including the mandible was artificially prepared with midfacial and orbital fractures and scanned using a 64-multislice CT scanner. The CT dose index volume (CTDIvol) and effective doses were calculated using application software. Noise was evaluated as the standard deviation in Hounsfield units within an identical region of interest in the posterior fossa. Diagnostic quality was assessed by consensus reading of a craniomaxillofacial surgeon and radiologist. Compared with the emergency protocol at CTDIvol 35.3 mGy and effective dose 3.6 mSv, low-dose protocols down to CTDIvol 1.0 mGy and 0.1 mSv (97% dose reduction) may be sufficient for the diagnosis of dislocated craniofacial fractures. Non-dislocated fractures may be detected at CTDIvol 2.6 mGy and 0.3 mSv (93% dose reduction). Adaptive statistical iterative reconstruction (ASIR) 50 and 100 reduced average noise by 30% and 56%, and model-based iterative reconstruction (MBIR) by 93%. However, the detection rate of fractures could not be improved due to smoothing effects.

Objective The role of human papilloma virus (HPV) infections in oral carcinogenesis is an important topic of research in maxillofacial oncology. Nevertheless, the association between such infections in the oral cavity and the development of oral precancerous lesions remains unclear. The aim of this study was to evaluate the association between oral HPV infections and oral leukoplakia or erythroplakia. Study Design The case control study included 118 patients with manifest oral leukoplakia or erythroplakia, who underwent surgical biopsy, including a histopathologic grading of the lesion, and 100 control patients without any oral lesions. HPV detection was achieved with a noninvasive brush smear method (Digene Cervical Sampler, Hybrid Capture II-Test). Logistic regression analysis was performed to assess the associations. Results A significant association was found between high-risk oral HPV infection and the presence of oral premalignant lesions (P = .001). Among all other evaluated parameters, only smoking showed a significant association with the presence of oral lesions. Conclusions Oral HPV infections may play a role in the pathogenesis of premalignant oral lesions.

Purpose In computer-assisted implantation surgery, the transfer of prosthodontic-guided planning to the operative site is usually based on a registration template. The precise repositioning of the registration template is crucial for high accuracy and is compromised in edentulous jaws. The purpose was to determine the in vitro registration and targeting accuracy for surgical navigation in the edentulous jaw based on 3 fixed intraoral reference points. Materials and Methods Edentulous maxilla and mandible cadaver specimens were provided with 3 fixed reference-point screws. A resin template with matrices for the fixed reference-point screws was produced and connected to a Vogele-Bale-Hohner registration mouthpiece and external registration frame with a snap-lock system. Surgical implants were planned on computed tomographic data and the corresponding dental stone casts were drilled under guidance of an optical navigation system. For evaluation of the registration accuracy, fiducial registration error was recorded and application accuracy was evaluated by fusion of postsurgical computed tomographic scans of the drilled dental stone casts with the presurgical planning computed tomogram. Results In 9 maxillas and 5 mandibles, 14 registrations and 104 stone cast drillings were performed. The mean fiducial registration error was 0.49 ± 0.14 mm (0.37 to 0.9 mm). The mean total error at the tip of the borehole was 0.88 ± 0.65 mm (0.0 to 4.24 mm). The mean lateral errors were 0.51 ± 0.49 mm (0.0 to 2.80 mm) at the base and 0.46 ± 0.34 mm (0.0 to 1.5 mm) at the tip of the borehole, respectively. The mean angular error was 0.83 ± 0.60° (0.0 to 2.5°). Conclusion Three fixed intraoral reference points successfully support a registration mouthpiece and provide in vitro registration and targeting accuracy that is comparable to tooth-supported registration templates or bone marker registration.

A newborn female was referred with the following clinical symptoms: median tongue cleft, palate cleft, ankyloglosson, sublingual intraoral hamartoma and palatal intraoral hamartoma. Magnetic resonance imaging showed a subcutaneous cyst overlying the manubrium sterni. Genetic investigation (chromosome analysis) showed no aberrations and/or variations. The quick growth of the intraoral hamartoma required an excision at the age of 3 months. Under general anaesthesia the intraoral hamartoma was excised and the median tongue cleft was closed. Median tongue clefts are reported to be only associated with orofacial digital syndromes type I, II, IV and VI. If the clinical appearance is described without any association to an orofacial syndrome, the Tessier 30 cleft definition could be used as the best explanation of the symptoms. This is the first description of a combination of tongue cleft, palate cleft, intraoral hamartoma and subcutaneous cyst overlying the manubrium sterni. The clinical symptoms of this patient can be described best as a mild form of an orofacial digital syndrome type II or variation of a Tessier cleft No. 30.

Summary Although there have been recent advances in maxillofacial surgery and anaesthetic techniques, blood replacement is still common in orthognathic surgery. 179 patients underwent elective orthognathic surgery and donated autologous blood preoperatively. Standardized questionnaires about the preoperative blood donation were distributed to the patients. Haemoglobin, haematocrit, red blood cells and platelets were measured before blood donation, presurgically and postsurgically, as well as one year after surgery. Nearly all patients (98%) would recommend preoperative autologous blood donation. 97% of the patients saw the benefits of autologous blood donation in avoiding transfusion-transmitted infectious diseases such as acquired immune deficiency syndrome (AIDS) and hepatitis. No serious side-effects have been observed after blood donation. In patients with bimaxillary osteotomies (65% of the predeposited autologous blood units) 41% were in cases having upper jaw osteotomies and only 22% of the preoperatively donated units were retransfused in patients having lower jaw osteotomies. After a postsurgical decrease, the mean haemoglobin and mean haematocrit levels regained the levels determined prior to the donation. Preoperative autologous blood donation of 2 to 3 units (900–1350 ml ± 10%) of blood is recommended in bimaxillary osteotomies and 1 to 2 units (450–900 ml ± 10%) of blood for upper jaw osteotomies. In lower jaw surgery, the acute isovolaemic haemodilution should be considered.