Survival of retained permanent canines after autotransplantation: A retrospective cohort study.

INTRODUCTION: After third molars, canines are the teeth most commonly affected by displacement and impaction. Although orthodontic surgical treatment represents the standard method for realignment of canines, autotransplantation (autoTX) functions as the second-line therapy if orthodontic alignment does not succeed in treating impaction and severe displacement. This retrospective cohort study aimed to identify clinical predictors for postoperative survival and endodontic treatment needs after autoTX of severely displaced and impacted canines. METHODS: The study cohort comprised patients who received canine autoTX in a single surgical center between 2006 and 2018. Canines with severe displacement and retention were surgically treated using a standardized protocol. Statistical analysis of survival probability was performed with the Kaplan-Meier method, and bivariate data were analyzed using logistic regression and the Pearson chi-square test. Nonparametric continuous variables were analyzed using the Mann-Whitney U test. RESULTS: Data from 319 patients with 378 canine grafts were available for analysis after a mean follow-up of 54.7 ± 36.5 months on the patient level (range, 0.3-181.8 months). With 25 lost autotransplants, the cumulative survival rate was 93.4%. Patient age at surgery, the state of the apical foramen, endodontic treatment need, and persistence of deciduous teeth at the implantation site had a significant negative impact on autotransplant survival (P <0.05). Endodontic treatment need was significantly related to the patient's age at surgery, the state of the apical foramen, and preoperative orthodontic traction (P <0.05). Thus, these independent variables were identified as clinical predictors for the survival of both the autotransplant and the dental pulp. Gender, ischemia time, postoperative ankylosis, or site of autoTX did not influence any of the outcome variables. CONCLUSIONS: The high survival rates of autotransplanted permanent canines make this treatment a promising option, especially in patients with severe tooth displacement, in which orthodontic treatment alone cannot provide predictable alignment, irrespective of the patient's age. Interpreting age and preoperative orthodontic traction as delaying the onset of autoTX and state of apex, time-dependent aspects seem to be of great importance for postoperative complications leading to endodontic treatment or graft loss. Therefore, early implementation of autoTX as a treatment modality for impacted, severely displaced, and vain exposed canines in daily surgical practice should be encouraged.

Primary tooth autotransplantation: update and retrospective clinical study.

OBJECTIVE: A new technique of primary tooth autotransplantation has recently been published demonstrating reliable replacement of missing permanent incisors in young children due to trauma or agenesis. This retrospective clinical study reports on the longterm success of this new technique in a larger patient group regarding its potential to support bone and soft tissue growth. STUDY DESIGN: 40 children (age range: 2.7-17.6 years) received 53 primary tooth autotransplants (49 canines and 4 incisors) due to traumatic tooth loss (73%), agenesis (19%) or dysplasia/displacement (8%). Clinical and radiological follow-up examinations were performed to check up on root resorption, bone and soft tissue growth, survival and success. RESULTS: 22 transplants still present in the oral cavity of 18 patients yielded a success rate of 77%. The Kaplan-Meier estimator measured a median survival time of 86 months (7.2 years) for all 53 grafts. In all cases, increasing soft tissue and bone development enabled a successful prosthetic rehabilitation regarding aesthetics and function. CONCLUSIONS: Primary tooth autotransplantation reliably restores edentulous anterior space in children experiencing traumatic tooth loss or agenesis and acts as an immediate therapy before other therapies such as premolar transplantation or orthodontic space closure can be carried out at a later time. It guarantees the co-development of soft tissue and bone in the teenage jaw which is associated with high patient satisfaction and acceptance of this method.

Premolar autotransplantation in juvenile dentition: quantitative assessment of vertical bone and soft tissue growth.

OBJECTIVE: Premolar autotransplantation represents an effective therapeutic option for the treatment of juvenile dentition with either aquired or congenital hypodontia. The objective of this prospective clinical study was to quantitatively assess bone and soft tissue levels after autogenous premolar transplantation by clinical and radiographic parameters. STUDY DESIGN: In the study, 26 premolars were transplanted in 20 patients after traumatic tooth loss (n = 16) or congenital aplasia (n = 10) in the anterior maxilla. Based on standardized photographic documentation, the relative soft tissue level was measured compared to the healthy adjacent teeth. Radiographic findings included evaluation of root resorption, pulp canal obliteration, and relative bone height. RESULTS: Average survival rate of transplanted premolars (n = 26) was 100% over a follow-up period of 29 months (range 10-60 months). The relative soft tissue level significantly increased by +1.1 mm (P < .01). Radiographs showed a tendency toward vertical bone growth. Continuous root development and signs of pulpal healing were observed postoperatively in 18 transplants (69.2%). CONCLUSIONS: Autogenous premolar transplantation represents a safe method to ensure functional and aesthetic rehabilitation in the anterior maxilla irrespective of the nature of tooth loss.

Laser therapy of a dermal nevus in the esthetic zone of the nasal tip: A case report and comprehensive literature review.

This case report demonstrates the ablation of a dermal nevus using a diode laser in the esthetically very demanding facial area of the nasal tip. The clinical outcome shows good results and a high level of patient satisfaction. Due to effective wound granulation and healing, elaborate skin grafts could be avoided. The application of the contact laser ensures safe treatment in highly perfused areas thanks to haptic feedback and good coagulative effect. The method should therefore be considered as an alternative to other ablative procedures for benign lesions in the facial area.

Primary canine auto-transplantation: a new surgical technique.

OBJECTIVE: The aim of this study was to investigate whether the growth of soft tissue and bone in children with traumatic tooth loss or agenesis of teeth can be developed reliably, using a new technique of autogenous primary canine transplant. STUDY DESIGN: A total of 10 patients (age range, 7-13 years) were treated either for trauma or for agenesis (n = 14 primary canine transplants). In addition to the clinical examination, patients were subjected to radiologic examinations with regard to root resorption, bone height, and soft tissue level. RESULTS: With an average survival rate of 87%, the average survival time of the transplants using the Kaplan-Meier estimator was 5.2 years. In all cases, soft tissue and bone growth was effectively developed. CONCLUSIONS: Autogenous primary canine transplant is a reliable surgical method for rehabilitating children in the early mixed dentition after traumatic tooth loss, enabling adequate soft tissue and bone growth.

Autotransplantation and surgical uprighting of impacted or retained teeth: A retrospective clinical study and evaluation of patient satisfaction.

OBJECTIVES: This retrospective clinical study aimed to determine the success rate of autotransplanted impacted or retained teeth along with a patient satisfaction survey and to analyze the influence of relevant clinical and radiographic parameters. SUBJECTS AND METHODS: Fifty-seven teeth (37 canines, 10 molars, seven premolars, three incisors) in 45 patients (median 15 years) were evaluated over a mean of 1.6 years. The success criteria were pocket probing depth ≤3.5 mm, mobility grade ≤ II, Periotest ≤30 and complete alveolar bone healing. The influencing parameters were oral hygiene, smoking, periodontal screening index, occlusal/proximal contacts, horizontal position, dental age, pulp obliteration and degree of displacement. Furthermore, bone height was measured. RESULTS: The overall success rate was 74%, along with a high patient satisfaction. The survival rate was 96% after a mean follow-up of 1.6 years. The favorable factors were proper oral hygiene, non-smoking, good general periodontal condition, proximal contacts and pulp obliteration. An increase in or maintenance of bone level was found in 96%. CONCLUSIONS: Autotransplantation of impacted or retained teeth is an appropriate treatment, if orthodontic alignment has failed, especially in growing patients.

Atrophy of free fibular grafts after mandibular reconstruction.

BACKGROUND: In free fibular flap surgery, the graft's low vertical height and tendency to resorb over time have been considered potential drawbacks. This study investigated (1) short- and long-term bone resorption in free fibular grafts; (2) resorption behavior of fibular grafts versus dentulous and edentulous autochthonous mandibular bone; and (3) factors that potentially influence long-term bone atrophy, such as site of reconstruction, presence of osseointegrated dental implants, patient age, and adjuvant radiation therapy. METHODS: Between 1992 and 2004, 113 patients received free fibular grafts. Fifty-four of these patients were examined retrospectively. Postoperative Panorex examinations assessed loss of bone height per month. Standardized miniplate measurements served as a reference to prevent errors caused by projection on magnification. RESULTS: Follow-up ranged from 6 months to 12 years. According to Jewer's classification, the following defect types were found: L, 23 (42.6 percent); H, five (9.3 percent); C, two (3.7 percent); LC, 12 (22.2 percent); HC, nine (16.7 percent); and LCL, three (5.6 percent). Radiographic analysis revealed a monthly atrophy of 0.04 +/- 0.08 mm (mean +/- SD) for fibular bone, 0.14 +/- 0.11 mm for dentulous mandibula, and 0.20 +/- 0.17 mm for edentulous mandibula. The difference in bone loss between fibula and edentulous or dentulous bone was significant (Friedman's test and Wilcoxon paired-sample test, p < 0.0001 and p = 0.02, respectively). Investigated factors had no significant influence on bone resorption rate. CONCLUSIONS: Fibular grafts show short- and long-term stability. Their rate of atrophy is significantly lower than that of edentulous or dentulous mandibular bone. Thus, implants can be inserted into this bone graft just as successfully as they are inserted into adjacent mandibular bone when the same bone height is present.

Free flap monitoring using simultaneous non-invasive laser Doppler flowmetry and tissue spectrophotometry.

BACKGROUND: Early identification of flap failure is an indispensable prerequisite for flap salvage. Although many methods of free flap monitoring are available, there is still no single reliable non-invasive technique for early recognition of flap failure and for differentiation between arterial occlusion and venous congestion. The aim of this study was to investigate the benefits of the tissue oxygen analysis system O(2)C for monitoring patients undergoing maxillofacial reconstruction with fasciocutaneous radial forearm flaps. MATERIAL AND METHODS: In a prospective clinical study the microcirculatory parameters of blood flow, flow velocity, haemoglobin concentration (AU, Arbitrary Units) and oxygen saturation (%) were assessed by clinical means, by laser Doppler flowmetry and tissue spectrophotometry in 61 patients intraoperatively. Measurements were carried out before flap harvest, in the separated radial forearm flap, immediately after anastomoses and up to 14 days after reconstruction. RESULTS: Following anastomosis, blood flow and flow velocity exceeded the level before flap elevation and reached significant differences by the third postoperative day (p<0.05). Oxygen saturation decreased significantly by the third postoperative day and haemoglobin oxygenation showed stable values after performing anastomosis. Simultaneous, non-invasive laser-Doppler flowmetry and tissue spectrophotometry detected vascular complications in all cases with no false positive or false negative results and prior to clinical assessment. CONCLUSION: For the first time this new device allows reliable prediction of venous congestion by an increase of haemoglobin-concentration, and of arterial occlusion by a decrease in blood flow parameters and oxygen saturation. It can thus differentiate the mechanisms of flap failure before clinical assessment.

Bilateral synchronous submandibular lumps in a patient with gastric carcinoma.

This case report deals with a patient who was readmitted with a bilateral submandibular swelling after having received primary surgery due to gastric adenocarcinoma 6 months before. After bilateral submandibulectomy both glands were diagnosed histopathologically as metastasis of adenocarcinoma. This is the rare case of a submandibular gland metastasis and the first case of a bilateral synchronous submandibular gland metastasis from gastric carcinoma.

In vivo visualization of platelet/endothelium cell interaction in muscle flaps.

Increasing evidence underlines the substantial pathophysiological impact of platelets on the development of ischemia/reperfusion injury (I/R) in flaps. Methods for studying dynamic platelet mechanisms in flaps in vivo are not available. The aim of this study was to develop a model enabling quantitative analysis of platelet kinetics and platelet-endothelium cell interaction within the microcirculation of muscle flaps in vivo. Balb/c mice (n = 16) were anesthetized, and an epigastric muscle flap was prepared. Autologous platelets were separated from blood donor animals (n = 16) and labeled ex vivo by means of rhodamine-6-G. After I/R (90 minutes' clamping, 10 minutes' reperfusion), the platelets were administered intra-arterially (i.a.). Microhemodynamics and kinetics of platelets were investigated by intravital fluorescence microscopy. I/R of muscle flaps induced disturbances in microcirculation. The number of rolling platelets, as well as platelets adhering to the inner vessel wall of venules, was increased in the ischemia group. Using intravital fluorescence microscopy, platelet kinetics were analyzed directly in flap microcirculation in vivo for the first time. Since platelet/endothelial cell interaction is a key event in the pathophysiology after microsurgical procedures, this model will help to understand basic molecular mechanisms of platelet behavior during I/R.

Degradable injectable bone cement in maxillofacial surgery: indications and clinical experience in 27 patients.

BACKGROUND: A carbonated apatite cement (NORIAN SRS) was used as a bone mineral substitute for the calvaria or viscerocranium in 27 patients. It has the consistency of a paste and hardens at physiologic pH and body temperature due to dahllite crystallization, which has the stoichiometric formula Ca(8.8)(HPO(4))(0.7)(PO(4))(4.5)(CO(3))(0.7)(OH)(1.3). MATERIAL AND METHODS: The cement was used for posttraumatic bone defects in the orbital, periorbital or malar regions (nine patients), posttraumatic deformities of the frontal bone (six patients), tumour-dependent bony defects of the calvaria (two patients) and posttraumatic or cystic defects of the mandible (five patients). In another five patients, the material was used to augment the atrophic anterior mandible in combination with the insertion of dental implants. Follow-up varied between 6 and 40 months (mean: 29 months). RESULTS: There was no inflammatory reaction surrounding the implanted material. There was no sign of infection in any of the patients and only one case of partial wound dehiscence with superficially exposed material. The defect fillings and augmentations were successful in all patients. None of the 19 dental implants which were inserted in combination with the material showed any sign of infection or loosening. Also, there was no loosening of the implants after loading (mean follow-up: 15 months). From the check-up radiographs, the material could be seen as a dense, radio-opaque structure. There were no material fractures or dislocations. Radiologically, the material seemed to be completely replaced by bony tissue after 30 months. CONCLUSION: Our 5-year clinical experience suggests that the material is a suitable bone mineral substitute for cranio-maxillofacial surgery especially for moderate-sized defects of the calvaria and forehead bone. It has advantages over preformed, solid bone substitute materials, and, due to its initial plasticity and eventual great compressive strength, it can also stabilize dental endosseous implants in the atrophic mandible.

Perforator flaps from the lateral lower leg for intraoral reconstruction.

Perforator flaps are based on cutaneous, small-diameter vessels that originate from a main pedicle and perforate fascia or muscle to reach the skin. Although these flaps have recently become popular for soft-tissue reconstructions in nearly all regions of the body, the systematic application of perforator flaps with short, small-caliber pedicles for intraoral reconstruction has not been reported. Experience with the use of 10 consecutive perforator flaps from the lateral lower leg for intraoral defect coverage is reported. In 10 cases, a 4- to 6-cm-long septocutaneous or myocutaneous perforating vessel from the peroneal artery, with a diameter of 1 to 2 mm, could be identified in the proximal one-half of the lateral lower leg. The thin, pliable skin paddles, measuring up to 6 x 8 cm, were used for defect coverage after resection of squamous cell carcinomas of the floor of the mouth (five cases), soft palate (one case), tongue (two cases), or buccal mucosa (two cases). Anastomoses were performed to the lingual artery and concomitant vein. Except for one case, all perforator flaps healed without complications and the functional results were satisfying. At the donor site, which was always closed directly, an approximately 15-cm-long scar resulted, without functional impairments. The peroneal artery was regularly preserved. Perforator flaps from the lateral lower leg might have many applications for intraoral soft-tissue reconstruction, especially because of their minimal donor-site morbidity.

Chronic left heart catheterization for microvascular blood flow determination in the rabbit: a minimally invasive technique using specially designed port devices.

BACKGROUND: This study describes a modified catheterization technique with subcutaneously implanted port catheters to be inserted in a retrograde manner across the aortic valve into the left heart ventricle through the right carotid artery to measure organ perfusion. MATERIALS AND METHODS: The specially designed arterial port catheters were implanted in New Zealand rabbits (n = 11, 3.7 +/- 0.1 kg [mean +/- SEM]) under iv anesthesia (medetomidine/ketamine) and single-shot perioperative antibiotic therapy. Hemodynamics were registered continuously during the operation via an ear artery catheter. RESULTS: Implantation of ports was performed in all animals (11/11) without major complications (mean operation time: 70 +/- 3 min). We did not observe catheter-associated arrhythmia, fall in mean arterial pressure (MAP before and post OP: 70 +/- 2 and 68 +/- 2 Torr, respectively), or change in arterial oxygen saturation (SaO2 before and post OP: 89 +/- 3 and 95 +/- 2%, respectively). With a specifically modified microsurgical insertion technique, cerebral blood supply was effectively preserved as evidenced from postmortem histological examinations, cerebral blood flow determination with fluorescent microspheres, and measurement of S-100b protein serum concentrations, a specific marker of neuronal damage. The positioning of the catheter tip in the left ventricle was found to be correct in 10/11 animals. CONCLUSIONS: Repeated and atraumatic microsphere injections into the left ventricle have become feasible by transcutaneous puncture of subcutaneous port systems over several weeks under light sedation. Hence, this new approach (i) avoids the necessity of repeated intracardiac injections and port insertions via thoracotomy, thus reducing the perioperative stress for the animals, and (ii) allows for the first time minimally invasive repetitive and chronic measurements of regional organ blood flow under various experimental settings.