Unintentional hypotension from lidocaine infiltration during orthognathic surgery and general anaesthesia.

BACKGROUND: A probable causal relationship between submucosal infiltration of lidocaine, with adrenaline 12.5 microg x mL(-1), and untoward arterial hypotension during general anaesthesia for orthognathic surgery was investigated in two parts. METHODS: The first part of the study was open and non-randomised. The patients served as their own controls, receiving 5.4 mL saline/adrenaline before mandibular or maxillary surgery on the first side of the jaw and 5.4 mL lidocaine (2%)/adrenaline on the other side a minimum of 40 min later. Nine patients received in total 11 pairs of injections of the study drugs. In Part Two, 50 mg or 100 mg of lidocaine with adrenaline was infiltrated in an observer-blinded and randomised order in either side of the jaw in another 13 patients. RESULTS: A significant and dose-dependent blood pressure decrease was observed after infiltration of lidocaine/adrenaline, but not after saline/adrenaline. The heart rate increased significantly after both types of injections, most pronounced after saline/adrenaline. Mean arterial blood pressure decreased on average 11% and 23% with lidocaine 50 mg and 100 mg, respectively (P<0.05, ANOVA). CONCLUSION: Lidocaine induced dose-dependent arterial hypotension when combined with a defined level of general anaesthesia. The causative mechanism is unclear.

Bone grafting to the maxillary sinus from the lateral side of the mandible.

Patients who were unable to have an implant of the maxilla without a bone graft were operated on by a modified sinus lift method, under local anaesthesia. Cortical bone grafts, harvested from the lateral side of the mandible, were forced horizontally into a slot, made in the lateral sinus wall after a mucosal sinus lift. The immediate stabilization of the graft permitted the dense packing of the space below the horizontal graft with bone chips, which probably contributed to the fast healing of the bone. We saw eight patients (10 sites) for long-term follow-up. Two or three Brånemark standard implants were inserted into the grafted area 3 months postoperatively. The abutments were connected 5 to 6 months after implantation. We have now adopted this modified method as the standard for bone grafting to the maxillary sinus in both of our maxillofacial centres.

Placement of posterior mandibular and maxillary implants in patients with severe bone deficiency: a clinical report of procedure.

The purpose of this investigation was to modify the method for implant placement in the posterior parts of the arches for fixed implant-supported prostheses using minimally invasive surgery. Eighty-six implants were placed posterior to the mental foramina in patients with severely resorbed mandibles, and 75 implants were placed in the posterior severely resorbed maxilla. Bone grafting from the mandible to the maxillary sinus was performed in 9 patients with severely atrophic maxillae. In all patients, optimal use of the anatomic features of the arch was achieved by tilting the implants. Patients were followed up for 12 to 123 months after prosthesis connection (mean 18 months). Three maxillary implants were lost at the time of abutment connection: 1 in the pterygoid plate, 1 close to the posterior sinus wall, and 1 placed in the palatal cortex. One implant was mobile approximately 1 year later, apparently because of an ill-fitting prosthesis. In the mandible, no implants were lost. The method described for the treatment of edentulous arches represents an alternative therapy to several others currently in use. This minimally invasive surgical procedure should be applicable in an outpatient clinic for treatment of severely resorbed posterior portions of the arches with implant-supported prostheses.

Tilting of posterior mandibular and maxillary implants for improved prosthesis support.

Rehabilitation of atrophied edentulous arches with endosseous implants in the posterior regions is often associated with anatomic problems such as jaw shape and location of the mental loop, mandibular canal, and maxillary sinuses. The purpose of this investigation was to modify the method for implant placement in the posterior part of the jaws to extend fixed implant-connected prostheses further distally, and to reduce the length of cantilevers in complete-arch prostheses without transpositioning the mandibular nerve or performing bone grafting in the maxilla. Forty-seven consecutive patients were treated with implants (25 patients/36 mandibular implants, 22 patients/30 maxillary implants) placed in tilted positions. They were followed a mean of 40 months (mandibles) and 53 months (maxillae). In the mandible, implants close to the mental foramina were tilted posteriorly approximately 25 to 35 degrees. In the maxilla, the posterior implants were placed close to and parallel with the sinus walls and were titled anteriorly/posteriorly approximately 30 to 35 degrees. Patients gained a mean distance of 6.5 mm of prosthesis support in the mandible and 9.3 mm in the maxilla, as a result of implant tilting. There were no implant failures in mandibles. The cumulative success rates in the maxilla at 5 years were 98% for tilted implants and 93% for non-tilted implants. Paresthesias of the mental nerve were observed on 4 sides during the first 2 to 3 weeks after implant placement. Analysis of the load distribution in one mandibular case showed no significant difference between tilted and the non-tilted implants, and the improved prosthesis support was confirmed. Satisfactory medium-term results concerning osseointegration and significant extension of prosthesis support show that the method can be recommended. This technique may allow for longer implants to be placed with improved bone anchorage.

Effects and adverse events of a dental appliance for treatment of obstructive sleep apnoea.

In a prospective study, 95 patients with mild to moderate obstructive sleep apnoea (OSA) were randomised to receive either surgical treatment, uvulopalatopharyngoplasty, (4-6 patients) or treatment with a nocturnal dental appliance for mandibular advancement (49 patients). Of the 49 dental appliance patients, 37 completed the 12-month follow-up. The aim of this study was to evaluate the effects and adverse events of dental appliance treatment from a one-year perspective. Somnography was employed to measure treatment effects before and 12 months post-treatment. At the 12-month control, somnography was performed twice: the first time with the dental appliance and the second time without it. Adverse events were recorded 2 weeks and 3, 6, and 12 months after treatment was initiated. The patients used the dental appliance on average 6 nights/week. After 12 months of treatment, the apnoea, apnoea/hypopnoea, oxygen desaturation, and snoring indices decreased significantly. Ninety-five per cent of the patients reduced their apnoea index by > or = 50% and 78% of the patients were normalised following treatment. At the somnographic registration without the dental appliance, the values were found comparable to what they were before treatment. Mandibular mobility and occlusion were constant throughout the study. The adverse events resulting from using the dental appliance were relatively minor and infrequent, and no serious complications were observed except for two patients who reported pain from the temporomandibular joint. In conclusion, the dental appliance has been shown to be a valuable treatment method for mild to moderate OSA with few adverse events in the stomatognathic system or other complications.

A prospective randomized study of a dental appliance compared with uvulopalatopharyngoplasty in the treatment of obstructive sleep apnoea.

The enthusiasm for uvulopalatopharyngoplasty (UPPP) in the treatment of obstructive sleep apnoea (OSA) has declined in recent years, partly because of a lower success rate over time and partly because of adverse effects. Reports on the beneficial effects of dental appliances exist, but only one prospective randomized study has been published comparing dental appliances with nasal continuous positive airway pressure (CPAP) treatment. No study has been published comparing dental appliance treatment with UPPP. Ninety-five male patients with confirmed OSA, subjective daytime sleepiness and an apnoea index (AI) > 5 were randomized for subsequent treatment with either a dental appliance or UPPP. There were 49 patients in the dental appliance group and 46 in the UPPP group. Thirty-seven patients in the dental appliance group and 43 in the UPPP group completed the 12-month follow-up. The success rate (rate of patients with at least a 50% reduction in AI) for the dental appliance group was 95%, which was significantly higher (p < 0.01) than the 70% success rate for the UPPP group. According to the criteria for OSA (apnoea index > or = 5 or apnoea/hypopnoea index > or = 10), 78% of the dental appliance group and 51% of the UPPP group were normalized after 12 months. The difference between the groups was significant (p < 0.05). These findings suggest that the dental appliance technique is useful in the treatment of mild to moderate OSA.

Anterior-inferior mandibular osteotomy in treatment of obstructive sleep apnea syndrome.

In a prospective randomized study on treatment of obstructive sleep apnea syndrome, anterior-inferior mandibular osteotomy with the purpose of stretching the suprahyoidal muscle was performed as one of the treatment methods. Ten men aged 20 to 65 years, without cardiovascular or neurologic disease, with normal maxillomandibular relation, and having an apnea index between 5 and 25 were included in the study. After a specially designed osteotomy of the chin, the anterior suprahyoidal muscles were detached, stretched approximately 10 to 12 mm, and sutured. The chin was then placed in its original position and post-operative evaluation was performed. Although there were initial reports of decreased daytime sleepiness and less snoring after surgery, the results after 12 months were discouraging. Somnographic registration (apnea index, apnea/hypopnea index, and oxygen desaturation index) as well as cephalometric analysis failed to show positive results. Hence, suspension of the suprahyoidal muscles as a method of treatment for obstructive sleep apnea syndrome cannot be recommended.

Induced hypotension may influence blood loss in orthognathic surgery, but it is not crucial.

The need for induced hypotension in orthognathic surgery was evaluated. Blood loss, duration of operation, quality of the surgical field, and surgical result were measured in 36 patients, assigned to either hypotension (mean arterial pressure, MAP, 50-64 mmHg) or normotension (MAP > or = 65 mmHg). Hypotension was achieved by increasing the amount of isoflurane given. The hypotensive group had significantly less bleeding over time (mean 0.9 ml/minute, 95% confidence interval (CI) of mean 0.6 to 1.2, compared with 1.8, 95% CI 1.3 to 2.4, p = 0.005). The corresponding difference in total blood loss did not differ significantly between the groups (mean 186 ml, 95% CI 98 to 275, compared with 304, 95% CI 210 to 399). No patient required transfusion of red cells. Neither the duration of surgery, nor the quality of the surgical field, nor the final result were significantly influenced by hypotension. The clinical relevance of induced hypotension in orthognathic surgery must be considered to be doubtful. A mean reduction of less than 150 ml will be of limited value at the low levels of blood loss reported.

A modified method of simultaneous bone grafting and placement of endosseous implants in the severely atrophic maxilla.

The purpose of this investigation was to clinically evaluate the modified method for surgical rehabilitation of severely atrophied maxillae with titanium implants. In 35 patients, sinus lift, Le Fort I osteotomy, and a downtilting of the maxilla were performed. Bone grafts from the iliac crest, placed between the sinus mucosa and the sinus floor, were secured with three to four Bränemark titanium implants 10 to 20 mm in length on each side. The osteotomized maxilla was stabilized with miniplates. The observation period was between 1 and 4 years after abutment connection. The rate of successful osseointegration was 86.6%.

Reverse genioplasty.

The purpose of this investigation was to evaluate the possibility of correcting the appearance of a protruded or retruded chin through relocation of the anterior alveolar segment. Five patients with a protruded chin (group I) were treated by anterior repositioning of the alveolar segment, while five patients with a retruded chin (group II) were treated through posterior repositioning of the mandible. In the patients in group I, the convexity of the chin became less pronounced and the most anterior point of the soft tissue chin curvature (pogonion) moved superiorly. In the patients in group II, the convexity of the chin become more pronounced. The position of soft tissue pogonion was unchanged. The ratio of the segment-lip movement in both groups was close 1:1. The method is easy to perform and provides predictable results. For patients with a protruded chin, in whom reduction genioplasty often offers a poor result, the procedure described could be a method of choice.

Soft tissue response to genioplasty procedures.

The soft tissue response to genioplasty procedures was studied in 65 patients. The patients were divided into four groups depending on the direction of the genioplasty. In 17 patients straight anterior repositioning was made (group I), in 12 patients posterior repositioning of the chin (group II), in 19 patients vertical reduction of the chin (group III) and in group IV superior-anterior repositioning of the chin. The predictability of the procedures varied. The soft tissue response was equal to the bone movement in the anterior repositioning but less predictable in the posterior direction or when combined with vertical reduction.

Transverse surgical correction of the maxilla. A modified procedure.

A modified surgical procedure to expand as well as reduce the width of the hard palate is described. Instead of a single sagittal osteotomy in the midline of the palate, multiple sagittal osteotomies are performed parallel to each other and maintaining the periosteal attachment to each of the fragments. The hard palate is thereby moveable and can be reduced in a transverse direction as well as expanded. The expansion will, however, be limited to the height of the curvature of the palate. Minor complications with the method are described. Long-term postoperative follow-up shows stable results with the method.

Posterior repositioning of the entire maxilla without postoperative intermaxillary fixation. A clinical and cephalometric study.

In 30 patients posterior repositioning of the entire maxilla has been performed. No postoperative intermaxillary fixation (IMF) has been applied. The surgical procedure is described and data given on the distance of repositioning. Results of cephalometric analysis indicate good long-term stability after surgery. We concluded that omitting IMF not only enhances patient comfort, but has no deleterious effect on postoperative stability of the maxilla.

Adverse effects on the brain in connection with isoflurane-induced hypotensive anaesthesia.

As a marker of brain cell injury, adenylate kinase (AK) was measured in cerebrospinal fluid (CSF) in 10 patients given anaesthesia with isoflurane-induced hypotension for corrective surgery of dentofacial deformities. Nine out of 10 patients displayed a marked increase in CSF-AK postoperatively compared with preoperative values. The postoperative mean value displayed a 400% increase compared to the corresponding preoperative value. This difference was statistically significant (P = 0.001). The rise in CSF-AK was most probably the result of an enhanced efflux of AK into CSF subsequent to a presumed hypoxic injury to brain cells.

Sagittal split osteotomy of the mandible without postoperative intermaxillary fixation. A clinical and cephalometric study.

A modified sagittal split technique has been evaluated in 42 dentate patients, in whom no postoperative intermaxillary fixation was used. Twenty-three patients had mandible set-back performed and 19 patients mandibular advancement. The method makes possible a safe split osteotomy under controlled conditions. The design of the osteotomy and screw osteosynthesis counteracts relapse. Omitting intermaxillary fixation facilitates postoperative handling of the patient and promotes rehabilitation.

Maxillary osteotomies without postoperative intermaxillary fixation (anterior, superior and inferior repositioning of entire maxilla). A clinical and cephalometric study.

Surgical correction of maxillary anomalies with anterior-superior or anterior-inferior repositioning of the segment was performed in 50 patients. The maxillary segment was stabilized by means of steel wires as horizontal mattress sutures, which, in all cases, gave very good primary stability. In case of insufficient bone contact miniplates were used. Postoperatively no rigid intermaxillary fixation (IMF) was applied. There are several advantages to not using intermaxillary fixation: 1) It is possible to carry out immediate postoperative inspection of the location of the condyles and thereby confirm that the segments are in the expected position. 2) Segment fixation is not disturbed by mandibular movements during recovery from general anaesthesia. 3) Manipulations by the anaesthesiologist immediately after surgery are not interfered with. 4) For the patient there is better postoperative comfort with no breathing, talking or feeding problems. 5) Minor corrections of intercuspation by means of orthodontic elastics are possible. These can act in the required direction and will not disturb the masticatory function. Masticatory function was resumed immediately after surgery and was usually normalized within 2-3 weeks. Cephalometric analysis revealed no significant relapse subsequent to surgery. Thus we conclude that omitting IMF, among other advantages, enhances patient comfort and has no negative effect on the postoperative stability of the maxilla.

Orthognathic surgery without the use of postoperative intermaxillary fixation. A clinical and cephalometric evaluation of surgical correction of mandibular and maxillary deformities.

The present series of investigations was performed in order to study the clinical and cephalometric long-term postoperative stability of the maxilla and mandible after surgical correction of jaw abnormities. The patients studied had maxillary or mandibular anomalies, alone or in combination with each other. Standardized surgical methods for correction of jaw deformities were used. Rigid postoperative intermaxillary fixation was omitted in all cases. Masticatory function was recommended immediately after surgery and was increased at the patient's own pace. Patients were able to eat all kinds of food 2-4 weeks postoperatively, independent of type of surgical procedure. The clinical results were good. Intraoperative complications, such as bleeding, unpredictable segment fracture during the splitting procedure, and damage to the neurovascular bundle or roots were negligible. The incidence of postoperative infections was very low. Such infections were limited to the region close to the osteosynthesis material and cleared up as soon as the wires or screws were removed. Paresthesia of the lower lip was seen with the sagittal split procedure especially when it was combined with genioplasty, but disappeared within one year. Standardized pre- and postoperative clinical and roentgenological recordings were made. In order to evaluate the postoperative stability of the osteotomized jaw segments cephalometric analysis of headfilms taken preoperatively, immediately postoperatively and at least one year after surgery was performed. There were no clinically significant postsurgical changes in the position of the maxilla, either in solitary procedures or in bimaxillary corrections. With mandibular advancement the mandible had moved slightly upwards and with setback surgery there was a slight post-surgical forward-upward movement. Omission of postoperative intermaxillary fixation, in combination with swelling or difficulties in nasal breathing, disturbed the tight intercuspidation immediately after surgery. The small changes seen were thought to be the result of tighter inter-cuspidation at the follow-up registration than on the day after surgery.

Simultaneous correction of maxillary and mandibular dentofacial deformities without the use of postoperative intermaxillary fixation. A clinical and cephalometric study.

Simultaneous correction of maxillary and mandibular anomalies was performed in 23 patients. The maxillary segment was stabilized by means of steel wires as horizontal mattress sutures, which, in all cases, gave good stability. A modified sagittal split has been applied in all cases. The method makes a safe split osteotomy possible under controlled conditions. The design of the osteotomy and the screw osteosynthesis counteract relapse. Postoperatively, no rigid intermaxillary fixation (IMF) was used. Masticatory function was started from the 1st postoperative day and in most cases was normalized 2-3 weeks after surgery according to the patients own judgement. Cephalometric analysis was performed on 15 patients by a superimposition technique. There was an overall good postoperative stability of the maxilla and mandible in the horizontal and vertical planes. We conclude that omitting IMF has no negative effect on the postoperative stability of the fragments.

Insect bite associated Kaposi's sarcoma with oral lesions.

A case of Kaposi's sarcoma with oral, pharyngeal and extremity lesions is reported. The first lesion appeared on the spot of an insect bite on the left leg during a stay in the Mediterranean area. Possible viral transmission by this route is discussed.

Miniplate osteosynthesis of infected mandibular fractures.

Miniplate osteosynthesis in cases of infected mandibular fractures in patients with reduced healing capacity and lack of cooperation has been evaluated. Thirty seven patients with 42 potentially infected mandibular fractures were treated by internal fixation with miniplates. Healing occurred in all cases. Postoperative infection was noted in 9 patients. Aspects of healing and indications for the method are discussed.