Effects of radiation therapy on craniofacial and dental implants: a review of the literature.

OBJECTIVES: The theories of the effects of radiation therapy on craniofacial and dental implants have been challenged by new models. Animal and clinical studies differ on the importance of dose effect and implant location regarding implant survival. Our purpose was to explore the risks of irradiation regarding dose levels, timing of radiation, implant location, and material. STUDY DESIGN: A systematic search of the literature was performed to identify studies reporting animal and human data on the success of implants in irradiated versus nonirradiated bone. RESULTS: Eleven animal studies exploring histomorphometric, biomechanical, and histologic features of implants in irradiated bone were summarized. Sixteen human clinical studies evaluating craniofacial (n = 8) and dental (n = 8) implants in irradiated bone were summarized. No meta-analyses of dental implants in irradiated bone were found. Efficacy studies comparing different implant types in irradiated bone were not found. CONCLUSION: Studies from both animal subjects and human patients indicate that irradiated bone has a greater risk of implant failure than nonirradiated bone. This increase in risk may be up to 12 times greater; however, studies making these comparisons are of poor to moderate quality, so the magnitude of this difference should be accepted with caution.

[Neonatal cervical teratoma: case report]. / Neonatales zervikales Teratom: Falldarstellung.

Cervical teratomas are extremely rare tumours. Surgery of these mostly benign malformations is very challenging for a multidisciplinary team. A single case of a newborn, who was imminently prenatally diagnosed with a neck mass, is presented. After delivery the patient was transferred to neonatal intensive care unit and intubation was performed. A rapid growth of the mass required early surgery and removal of the neck mass was performed on the third day post delivery. Histological investigation showed an immature teratoma. The postoperative period was complicated by hypothyroidism. Due to severe laryngo-tracheomalacia tracheostomy was required when the baby was 2 weeks old. Further development has been without any sign of recurrence (12 months). On the basis of this case differential diagnosis, therapy and outcome is discussed.

[Orbital volume in congenital clinical anophthalmos]. / Orbitavolumetrie bei kongenitalem klinischen Anophthalmus.

INTRODUCTION: The purpose of this study is to report orbital volume measurement results in patients with congenital clinical anophthalmia before and after therapy and to compare them with normal values. PATIENTS AND METHOD: Normal values were obtained from 35 healthy children (22 boys, 13 girls; aged 3 month to 7 years) in whom MRI was done for non-ophthalmological reasons. 18 patients with congenital anophthalmos could be included, 9 with bilateral, 8 with unilateral disease and 1 microphthalmos. 6 of them had MRI follow-up (more than one examination). RESULTS: Orbital volume at birth is 7 ml and it increases with age: Orbital volume = 7.701 x age (month) (0.2484) ml. It is around 14.2 ml at the age 1 year, 17 ml with 2 years and reaches 23 ml with 7 years. In unilateral clinical anophthalmos orbital volume is 35 to 58 % compared with the healthy side and 31 to 65 % compared with the normal values. In bilateral cases the volume is 43 to 70 % of the normal value. During treatment it develops in parallel to the normal values. CONCLUSIONS: The normal values measured by our group are in accordance with the only published study by Bentley . MRI orbital volumetry is a reliable method without using radiation. It allows us to quantify the bony asymmetry and is suitable for therapy control when using orbital expanders. The congenital missing eye might be the most important reason why the orbit does not develop in the normal way to a normal size. Self-inflating high, hydrophilic hydrogel expanders do not seem to be able to compensate this, in spite of the fact that they work very well to prepare the socket for a prosthesis.

[Facial clefts and their coding with LAHS nomenclature]. / Die LKGS(N)-Spalten und ihre Kodierung mit der LAHS-Nomenklatur.

Research and treatment of clefts of lip, alveolus, and palate requires exact, reliable and reproducible terminology and documentation. In this paper we suggest a simple system to record a detailed diagnosis for every case of cleft. All anatomical regions involved by the cleft are considered and the extent in these regions is described. This nomenclature has been proposed for usage by the Interdisciplinary Cleft Palate and Craniofacial Anomalies Committee of the German Associations for Cranio-Maxillofacial Surgery, Orthodontics, Phoniatrics, Pedaudiology and ENT.

[Development, standardisation and evaluation of a model for arthroscopic surgery of the joint. An experimental study in pigs]. / Das Landschwein als Modell für Ausbildung, wissenschaftliche Untersuchungen und Entwicklung neuer arthroskopischer Operationsmethoden am Kiefergelenk.

AIM OF THE STUDY: The aim of this study was to establish a reliable educational model for and a further refinement of arthroscopic surgery in the temporomandibular joint (TMJ). MATERIAL AND METHODS: As a first step, the lateral-medial (length) and anterior-posterior distances (width) of the mandibular head of nine pig cadavers (country breed) of about 30 ( n=3), 60 ( n=3) and 90 kg ( n=3) body weight were measured and compared with findings in 12 adult human cadavers. The best points of access for the arthroscopic and lavage channels using the triangulation technique were determined. As determined by these findings, 15 arthroscopies were performed on eight pig TMJs under general anaesthetic. A control arthroscopy was performed after 2 weeks followed by another clinical follow-up at 4 weeks before the pigs were sacrificed. RESULTS: The TMJ of the pigs between 30 and 60 kg body weight was found to be highly comparable to the human TMJ. The best locations for puncturing the upper joint compartment of the TMJ in pigs were 5.0 cm and 6.1 cm anterior to the tragus on a line drawn along the lower margin of the zygoma. The only complication encountered was a subcutaneous infection treated successfully by antibiotics and incision. CONCLUSIONS: In our opinion, a standard and easily reproducible model is necessary for further studies in arthroscopic TMJ-surgery. The country bred pig represents a good model for educational purposes and for studying further refinements of arthroscopic technique.

[Congenital clinical anophthalmia and blind microphthalmia]. / Kongenitaler klinischer Anophthalmus und funktionsloser Mikrophthalmus. Vergleichende Betrachtungen zu unterschiedlichen Therapiekonzepten.

Congenital anophthalmia and blind microphthalmia are very rare conditions and there is no standard treatment available. Various previously reported therapeutical concepts are reviewed. The clinical picture can be divided into three subgroups with different therapeutical options recommended: in microphthalmia the conjunctival sac size is usually normal or slightly decreased. The use of non-expandable conformers is possible with good results. Patients treated with hydrogel expanders can wear a prosthesis earlier and with better cosmetic results. In congenital anophthalmia the conjunctival sac is very small and contracted and patients cannot wear a prosthesis or even a conformer. Hydrogel expander treatment--first for the conjunctival sac and second for the orbit--is the therapeutical option which may lead to good cosmetic results. Children >5 years of age and/or unsuccessful pre-treated cases may benefit from osteotomy to reduce mid-face asymmetry. To attain the main therapeutical goal in this subgroup, the ability to fit a normal prosthesis, a combination of different techniques like hydrogel expanders, dermis fat graft, lid surgery etc. may be necessary.

[Treatment of congenital clinical anophthalmos with high hydrophilic hydrogel expanders]. / Therapie des kongenitalen klinischen Anophthalmus mit hoch hydrophilen Hydrogelexpandern.

INTRODUCTION: Children presenting with congenital anophthalmos usually develop a smaller bony orbit, a constricted mucosal socket, and a shortened eyelid fissure. This causes problems when fitting these patients with a prosthesis. Clinical evaluation of the Wiese self-inflating hydrogel expanders has demonstrated their ability to expand the socket and eyelid fissure for inserting a more realistic prosthesis in shorter periods of time. PATIENTS AND METHOD: The study included 13 consecutive anophthalmic patients, eight unilateral and five bilateral. Each patient received a hemispherical osmotic tissue expander in the rudimentary mucosal socket and later a sphere implanted in the deeper soft orbital tissue. RESULTS: The use of hydrogel expanders enlarged the lid and palpebral fissure in all children, with good cosmetic results. It allowed insertion of custom-made glass prostheses with good cosmetic appearance very early in life. Growth of the bony orbit may be stimulated successfully by these expanders in the soft orbital tissue. CONCLUSIONS: The enlargement of constricted mucosal sockets and short palpebral fissures using self-inflating hydrogel expanders is a new and successful concept in treating congenital anophthalmos.

Malignant conversion of florid oral and labial papillomatosis during topical immunotherapy with imiquimod.

We report a case of a 61-year-old woman suffering from florid oral papillomatosis with a squamous-cell cancer of the floor of the mouth, which was removed by scalpel surgery combined with a radical neck dissection in 1996. Between 1996 and 2000 several histologically benign papillomatous lesions of mouth and lips were removed with laser and electrosurgery. However, the lesions recurred. In July 2000 hyperkeratotic, wart-like lesions were present at the lower and upper lips and at the right angle of the mouth and the adjacent oral mucosa. Overnight treatment with a topical 5% imiquimod cream on a Monday-Wednesday-Friday schedule was initiated. However, due to severe irritation and pain the application had to be reduced to 4 h per night, three times a week, followed by a therapy-free interval of 2 weeks. Despite this treatment consisting of four cycles of 3 weeks (1 week treatment and 2 weeks pause), the lesions increased markedly in size. A biopsy taken from the tumorous lesion from the right angle of the mouth proved to be a squamous-cell carcinoma. The tumors of the labial and oral mucosal sites as well as the right submandibular lymph nodes were removed by wide scalpel excision. The lips were reconstructed by plastic surgery. 24 months after surgical intervention no recurrence nor metastasis to lymph nodes or distal sites were observed.

[Primary "swallowing" function in relation to cleft type after 18 years of interdisciplinary therapy]. / Primärfunktion "Schlucken" in Abhängigkeit von der Spaltform nach 18-jähriger interdisziplinärer Therapie.

PURPOSE: The aim of today's interdisciplinary treatment of clefts is complete aesthetic and functional rehabilitation of the patient. But is it possible to also achieve a physiological swallowing pattern? MATERIAL AND METHODS: At the Rostock cleft center patients are treated by an interdisciplinary approach from their day of birth until their 18th year of life. Tongue position during swallowing was investigated in 117 consecutive patients. They were assigned to four groups. The control group consisted of 197 age-matched patients receiving non-cleft orthodontic treatment. RESULTS: Patients with clefts of only the primary or only the secondary palate achieved physiological swallowing in 87% or 88% of cases at the age of 18. Of the unilateral CLP cases, 74% also had a physiological swallowing pattern, but in patients with bilateral complete clefts this pattern could be observed in only 46%. In comparison, 95% of non-cleft patients achieved a physiological swallowing pattern following orthodontic and speech treatment at the age of 18. The so-called anterior swallowing pattern was the pathological pattern found most often in cleft and non-cleft patients. CONCLUSION: In most cleft patients interdisciplinary treatment leads to a physiological swallowing pattern. Only patients with bilateral clefts of lip and palate have a critical prognosis. They need special care and attention.

[Millard gingivoperiosteoplasty. An alternative to osteoplasty of alveolar clefts]. / Gingivoperiostplastik nach Millard. Alternative zur Osteoplastik der Kieferspalte.

PURPOSE: The gingivoperiosteoplasty according to Millard is a possible alternative treatment modality to osteoplasty; no second operation for harvesting the bone graft is necessary. The goal of this investigation was the comparison of gingivoperiosteoplasty with osteoplasty and a search for factors that led to an improvement of the prognosis of both techniques. MATERIAL AND METHODS: Long-term results of 53 patients with 72 alveolar clefts who underwent gingivoperiosteoplasty and 74 patients with 103 clefts of the alveolus were analyzed radiographically following an osteoplasty at the age of 12-14 years. The amount of bone in the alveolar cleft was determined and related to a number of factors such as number of teeth, unilateral or bilateral cleft, and orthodontic treatment. The statistical analysis was done with the Mann-Whitney U-test (p < 0.05). RESULTS: The rate of success was similar following gingivoperiosteoplasty and osteoplasty with a range of 68% to 73%. A postsurgical orthodontic expansion of the alveolus and the existence of lateral incisors improved the prognosis for both techniques significantly (p < 0.05). Teeth erupted into the new periosteally formed bone. This was observed in 82% of those patients in whom enough bone was formed. CONCLUSION: The gingivoperiosteoplasty according to Millard is a real alternative to a common osteoplasty at the age of 12-years if a lateral incisor is found at both cleft margins and if postsurgical orthodontic expansion of the upper jaw is performed.

[Stimulating regeneration of bone defects by implantation of bioceramics and autologous osteoblast transplantation]. / Stimulation der Regeneration von Knochendefekten durch Einsatz einer Biokeramik und autologer Osteoblastentransplantation.

QUESTION: Does artificial stimulation of osteoconduction and osteogenesis lead to improved bone formation in defects of critical size? MATERIAL AND METHODS: Full-thickness, critical-sized defects in the anterior mandible were created in 24 adult mini-pigs. These defects were treated with a new kind of bioactive ceramic (60% hydroxylapatite and 40% beta-tricalcium phosphate), applied as a unique sol gel [9]. The bioceramic was tested alone and in combination with autologous osteoblasts. In a control group, periosteum was the only bone-producing source. After 5 weeks, the animals were sacrificed and the defects analyzed clinically, histologically, and by X-ray examination. The effects of periosteum, bioceramics, and osteoblasts were investigated in particular. RESULTS: The new bioceramic was degraded at the same speed as new bone was laid down. The rate of newly formed bone was highest in the bioceramic group at 72.3% (control group with periosteal covering only 59.3%). Additional transplantation of autologous osteoblasts did not result in faster bone production. CONCLUSION: It seems that this bioactive ceramic is successful as a bone replacement material and will be suitable as a carrier for osteoinductive substances such as bone morphogenetic proteins.

Traumatic myositis ossificans (ossifying pseudotumor) of temporal muscle.

The purpose of this paper is to present the clinical, radiographic, and histological aspects of a case of traumatic myositis ossificans of the temporal muscle. This is a rare, benign ossifying pseudotumor of skeletal muscles. It had developed 3 weeks after trauma to the left temple in a 33-year-old man. Differential diagnostic aspects of traumatic myositis ossificans confirming its benign character are discussed.

Virus infections and tumors of the oral mucosae. Symposium of the "Arbeitskreis Oralpathologie und Oralmedizin" and the "Arbeitsgemeinschaft Dermatologische Infektiologie der Deutschen Dermatologischen Gesellschaft", Rostock, July 6-7, 2001.

The symposium on Virus Infections and Tumors of the Oral Mucosae was organized as a joint meeting of the Arbeitskreis Oralpathologie and Oralmedizin and the Arbeitsgemeinschaft Dermatologische Infektiologie (ADI) der Deutschen Dermatologischen Gesellschaft. The main topics of the meeting were herpes virus infections, human papillomavirus (HPV) infections and human immunodeficiency virus (HIV) infections of the oral mucosae. Clinically both diagnostic, differential diagnostic and therapeutic aspects of the virus-associated diseases were discussed in several presentations. Another important issue was the role of these viruses, particularly of HPVs, in the origin and development of oral cancer. Apparently besides smoking and alcohol other risk factors comprise high risk HPVs, immunodeficiency and possibly also genetic factors. Whether neonatal early infections may predispose children to a specific cancer risk in their future life is still at a level of discussion. Some arguments, however were shown that tonsillar carcinoma, which shows the highest prevalence of the high-risk HPV 16- DNA sequences between all oral cancer, is possibly an epidemiologically and etiologically distinct tumor. It is argued that this tumor is probably less dependent on classical carcinogens than other oral malignant tumors.

Closure of vertical alveolar bone defects with guided horizontal distraction osteogenesis: an experimental study in pigs and first clinical results.

PURPOSE: To evaluate the option of treating alveolar clefts by guided distraction osteogenesis instead of applying osteoplasty with autologous bone grafts from iliac crest, rib or fibula. MATERIAL AND METHODS: At first, 30 land-bred pigs were operated upon. Treatment of each animal included creating bony defects measuring 2, 4 or 8 mm in the maxilla, anterior to the canine region and up to the nasal periosteum. In 15 of the 30 animals, a new horizontal segment distractor was tested. The device was placed in situ prior to creating an alveolar segment posterior to the defect. This segment was then transported gradually by distraction, thus crossing and closing the defect. At the end of the distraction and stabilization periods the newly formed bony tissue was examined. RESULTS: The critical size of defects was found to be larger than 4 mm. In five of six animals with a horizontal defect of 8 mm, complete ossification of the defect had occurred following distraction osteogenesis. This technique was then applied to five patients successfully. CONCLUSION: It was shown that distraction osteogenesis is a valid alternative for treating alveolar clefts.

The Eurocleft project 1996-2000: overview.

INTRODUCTION: The original Eurocleft project, a European intercentre comparison study, revealed dramatic differences in outcome, which were a powerful stimulus for improvement in the services of respective teams. The study developed a preliminary methodology to compare practices and the potential for wider European collaboration including opportunities for the promotion of clinical trials and intercentre comparison was recognized by the European Commission. Therefore, the project: 'Standards of Care for Cleft Lip and Palate in Europe: Eurocleft' ran between 1996 and 2000 and aimed to promote a broad uplift in the quality of care and research in the area of cleft lip and palate. RESULTS: The results of the 1996-2000 project include: a register of services in Europe, with details of professionals and teams involved in cleft care, service organization, clinical protocols and special facilities for research; a set of common Policy Statements governing clinical practice for European cleft teams, Practice Guidelines describing minimum recommendations for care that all European children with clefts should be entitled to and recommendations for Documentation governing minimum records that cleft teams should maintain; encouraging initial efforts to compare outcomes (results) of care between centres. A survey showed a wide diversity in models of care and national policies as well as clinical practices in Europe. Of the 201 centres that registered with the network, the survey showed 194 different protocols being followed for only unilateral clefts. CONCLUSION: Cleft services, treatment and research have undoubtedly suffered from haphazard development across Europe. Attainment of even minimum standards of care remains a major challenge in some communities and both the will to reform and a basic strategy to follow are overdue. It is hoped that the Eurocleft Consensus Recommendations reached during the present project will assist in improving the opportunities for tomorrow's patients. It is also hoped that the collaborative research now beginning under the European Commission's Framework V Programme will provide a focus for European researchers wishing to improve understanding, treatment and prevention of clefts of the lip, alveolus and palate in the years ahead.

Is it possible to prevent cleft palate by prenatal administration of folic acid? An experimental study.

OBJECTIVE: In this study, folic acid was tested for its antiteratogenic effects on experimentally induced cleft palate in animals. DESIGN: Eleven pregnant Lew 1 A dams (75 fetuses) received 200 mg/kg procarbazine via gastric tubing on postconception (p.c.) day 14 to induce a cleft palate (CP); seven of the pregnant dams (45 fetuses) were additionally given 4 mg/kg folic acid subcutaneously from the 14th to the 17th day p.c. As a control group, three more pregnant dams (24 fetuses) were not treated with the drugs mentioned above. All fetuses were delivered by Caesarian section on day 20 p.c. OUTCOMES MEASURED: All fetuses were weighed and examined macroscopically with a stereomicroscope. Each fetal head was cut into 35 frontal sections and scrutinized histologically. RESULTS: None of the control fetuses (n = 24) exhibited a cleft. Without folate administration, 90% of the fetuses (27 of 30) that received procarbazine exhibited a CP. After additional prenatal folate administration, this rate remained virtually unchanged (91%; 41 of 45). However, the proportion of complete (total) CP (4%) was significantly (p <.0001) lower than in the group without folate (53%). Cleft-associated microgenia and microglossia were also significantly less frequent when folate was administered prenatally: microgenia was reduced by 22% (p =.029) and microglossia by 24% (p =.032). CONCLUSIONS: On the basis of these results, folate has a partial ameliorating effect on the teratogenicity of procarbazine given to pregnant rats. Additional studies are necessary on the effect of folate in different species, also taking cleft lip and CP into consideration.

[Wavy incision of the soft palate. Modification of intravelar veloplasty]. / Wellenschnitt am weichen Gaumen. Modifikation der intravelaren Veloplastik.

PURPOSE: The problem with primary soft palate repair is shortness of the soft palate and a soft tissue deficit in this region. The authors introduce a modification of the intravelar veloplasty allowing lengthening of the soft palate at the time of primary closure. METHODS: The "soft palate wavy incision procedure" combines a wavy or undulating type of incision at the velar cleft margins with intravelar veloplasty. In 12 patients with complete clefts of the palate, postoperative breathing and speech was analyzed 3 years later. The investigator did not know whether a modification of the common procedure had been performed in these patients or not. RESULTS: It was found that the soft palate wavy line procedure is easy to perform and closure in three layers is possible even in wide clefts of the soft palate. No postoperative fistula was observed. An average lengthening of the soft palate of about 56% (24-83%) was achieved, measured immediately at the end of surgery. Three years later the patients have good speech results following this technique. CONCLUSIONS: Experience has shown that the soft palate wavy incision procedure is straightforward, safe, and easy. It seems that this technique leads to better results than classic intravelar veloplasty. This paper is only a first report, and further investigations are necessary.

[Wavy incisions for soft palate repair]. / Wellenschnitt am weichen Gaumen : Modifikation der intravelaren Veloplastik.

Purpose. The problem with primary soft palate repair is shortness of the soft palate and a soft tissue deficit in this region. The authors introduce a modification of the intravelar veloplasty allowing lengthening of the soft palate at the time of primary closure. Methods. The "soft palate wavy incision procedure" combines a wavy or undulating type of incision at the velar cleft margins with intravelar veloplasty. In 12 patients with complete clefts of the palate, postoperative breathing and speech was analyzed 3 years later. The investigator did not know whether a modification of the common procedure had been performed in these patients or not. Results. It was found that the soft palate wavy line procedure is easy to perform and closure in three layers is possible even in wide clefts of the soft palate. No postoperative fistula was observed. An average lengthening of the soft palate of about 56% (24-83%) was achieved, measured immediately at the end of surgery. Three years later the patients have good speech results following this technique. Conclusions. Experience has shown that the soft palate wavy incision procedure is straightforward, safe, and easy. It seems that this technique leads to better results than classic intravelar veloplasty. This paper is only a first report, and further investigations are necessary.