Is dental general anaesthesia in children an outdated concept? A retrospective analysis.

AIM: The aim of this retrospective study was to determine the prevalence of caries and treatment needs in the collective of patients ?16 years of age, who underwent scheduled dental general anaesthesia (DGA) at the University Clinic of Innsbruck from January 2015 to June 2019, with respect to demographic factors. MATERIALS AND METHODS: A retrospective analysis of children's diagnoses, demographics, and dental treatment under general anaesthesia in Innsbruck, Austria, from 2015 to 2019 was performed. Anonymised demographic data (age; gender; the presence or absence of general disease or disablement; parents' first language (German- (GS) or non-German-speaking (non-GS), reflecting ethnicity; and the number of teeth restored and extracted under DGA were collected from patients' files. Data was analysed by means of descriptive and comparative statistics. RESULTS: The main group consisted of 545 subjects at a median age of 5.3 (IQR 4.4-6.6) years, who had exclusively primary teeth and or first molars that received restorations or were extracted. Of the subjects, 84.4% were classified with uncooperativeness due to dental anxiety and 15.6% with systemic diseases or intellectual and or physical disablement. In this group, 47.9% were GS and 52.1% were non-GS or had GS or non- GS parents. In the total sample, 5 (IQR 3-7) primary teeth were restored and 4 (IQR 4-7) extracted. Subgroup analysis revealed statistically significant differences in the number of extracted primary teeth between children with and without systemic diseases or disablement - 3 (IQR 1-5) versus 4 (IQR 2-7) - and between children of GS and non-GS parents - 4 (IQR 2-6) versus 5 (IQR 3-7.8). Zero (IQR 0-0) first molars were filled and extracted. CONCLUSION: Within the study collective of children in poor oral health, the offspring of non-GS families were overrepresented (compared to their prevalence in the total population) and displayed a higher prevalence of deep caries than those of GS parents. By intensifying and special gearing of prophylactic measures to the non-GS population and promoting the parents' insight into the importance of oral hygiene and regular dental attendance, the demand for scheduled DGA might be greatly reduced. In the small share of children who suffer from severe diseases or disablement and are thus unable to cooperate with home care or dental treatment, DGA will remain the treatment of choice.

Prosthetic rehabilitation of patients with hypohidrotic ectodermal dysplasia: A systematic review.

Hypohidrotic ectodermal dysplasia (HED) comprises a large group of inherited disorders of ectodermal structures, characterised by hypo- or anhidrosis, hypotrichosis and hypo- or oligo- or anodontia. We aimed to systematically assess the spectrum of prosthodontic approaches with regard to the patients' age and to provide clinical implications for practicing dentists. An electronic and manual search was conducted in four databases (Medline, LIVIVO, Cochrane Library, Web of Science Core Collection). Publications of multiple study designs written in English or German without data restrictions, reporting on prosthodontic treatment of patients diagnosed with HED and afflicted with oligo- or anodontia, were included. In total, 75 articles on 146 patients were analysed according to the patients' age. In children aged 2-17 years, removable full or partial (over)dentures represented standard treatment. In the mandible, implant-supported removable dentures on two interforaminal implants presented an alternative, already in young childhood. In cases with more than six teeth per jaw, also fixed (resin) bridges were used, frequently after orthodontic treatment. In adults, fixed or removable reconstructions with the help of up to eight implants per jaw, usually placed after bone augmentation procedures, were standard. Ten case reports/series with long-term follow-up illustrated the need for consistent maintenance including denture renewals. Prosthodontic rehabilitation should start in early childhood and needs to be revised in accordance with the patients' growth. Treatment should be carried out by a multidisciplinary team addressing variable demands in different age groups.

Influence of CAD/CAM fabrication on denture surface properties.

Three main properties are responsible for the microbial attractiveness of denture surfaces: roughness, hydrophilicity and free surface energy. This study investigated whether CAD/CAM-fabricated dentures are more favourable for these surface properties than conventionally fabricated dentures. The mucosal surface roughness of 54 standardised study dentures was measured using contact profilometry. The surface hydrophilicity and free surface energy of 70 standardised denture resin specimens were determined by contact angle measurements. Both experimental settings compared AvaDent (AD), Baltic Denture System (BDS), Vita VIONIC (VV), Whole You Nexteeth (WN) and Wieland Digital Dentures (WDD) surfaces with conventionally manufactured denture surfaces (control group). These data were analysed using ANOVA together with Tukey's test or the Games-Howell post hoc test. All CAD/CAM dentures had lower mean surface roughness values than conventional dentures. For AD, VV, WN and WDD, the differences were statistically significant. Vita VIONIC (P < .001), coated WN (P < .001), AD (P = .023) and BDS specimens (P = .027) were significantly more hydrophilic than the control group. All measured surface energies were of similar magnitude (mean values between 31.82 and 33.68 mJ/m2 ), and only coated WN specimens had a significantly increased mean value (66.62 mJ/m2 , P < .001). Although most CAD/CAM dentures have smoother and more hydrophilic surfaces than conventional dentures, there is no difference in their free surface energy, except for coated dentures.

Shortcomings of prosthodontic rehabilitation of patients living in long-term care facilities.

Removable dentures are a non-invasive, cost-effective prosthodontic solution for the reduced dentition. Their intended purpose is the rehabilitation of harmonious oral function and aesthetics on a long-term basis. The prevalence of removable dentures among patients of advanced age is high and the quality of the dentures is often poor. The aim of this study was to find the most important shortcomings of removable dentures and address the main targets for improving the quality of prosthodontic rehabilitation. The records from dental check-ups in Austrian residential homes were analysed retrospectively. Dental anamnesis questionnaires and data from the clinical examinations of 105 denture wearers were analysed. The functional condition and retention of 192 dentures had been assessed, as well as the impact of the dentures on the intra-oral tissues. Insufficient denture retention was very common, particularly in the lower jaw (56·0%). Problems with the masticatory function were reported by 26.7% of the denture wearers, 11·4% were dissatisfied with the denture aesthetics, and 4·8% had difficulties with phonetics. Traumatic ulcers were found in 18·1%. Cracks, broken pieces (6·3%) or missing denture teeth (2·1%) were rare. It may be assumed that the findings of the present study also apply to a great percentage of community-dwelling seniors. The most important issues in prosthodontic rehabilitation with removable dentures are denture retention and masticatory function. Regular dental check-ups, denture adjustment and, when necessary, relining can maintain the primary denture quality and prevent damages of the oral tissues caused by ill-fitting dentures.

Failure analysis of fractured dental zirconia implants.

OBJECTIVES: The purpose of the present study was the macroscopic and microscopic failure analysis of fractured zirconia dental implants. METHODS: Thirteen fractured one-piece zirconia implants (Z-Look3) out of 170 inserted implants with an average in situ period of 36.75±5.34 months (range from 20 to 56 months, median 38 months) were prepared for macroscopic and microscopic (scanning electron microscopy [SEM]) failure analysis. These 170 implants were inserted in 79 patients. The patient histories were compared with fracture incidences to identify the reasons for the failure of the implants. RESULTS: Twelve of these fractured implants had a diameter of 3.25 mm and one implant had a diameter of 4 mm. All fractured implants were located in the anterior side of the maxilla and mandibula. The patient with the fracture of the 4 mm diameter implant was adversely affected by strong bruxism. By failure analysis (SEM), it could be demonstrated that in all cases, mechanical overloading caused the fracture of the implants. Inhomogeneities and internal defects of the ceramic material could be excluded, but notches and scratches due to sandblasting of the surface led to local stress concentrations that led to the mentioned mechanical overloading by bending loads. CONCLUSIONS: The present study identified a fracture rate of nearly 10% within a follow-up period of 36.75 months after prosthetic loading. Ninety-two per cent of the fractured implants were so-called diameter reduced implants (diameter 3.25 mm). These diameter reduced implants cannot be recommended for further clinical use. Improvement of the ceramic material and modification of the implant geometry has to be carried out to reduce the failure rate of small-sized ceramic implants. Nevertheless, due to the lack of appropriate laboratory testing, only clinical studies will demonstrate clearly whether and how far the failure rate can be reduced.

The Endo-Distractor for preimplant mandibular regeneration.

OBJECTIVE: A simple practical device for a new technique of vertical distraction osteogenesis was developed. The Endo-Distractor Krenkel was originally intended for the anterior regeneration of highly atrophic mandibles. The Endo-Distractor features several novelties. Placement is made intraosseously in the basal cortical bone. The distraction screw length may be adapted to the depth of chin soft tissues. The quality of anchorage in the basal cortical bone guarantees the stability of the distraction vector. The endobuccal emergence is that of an artificial crown, and does not cause any patient discomfort. The device can easily be removed without secondary surgery. All kinds of implants may be placed after the retention time. This study's objective was to evaluate the use of the Endo-Distractor Krenkel in edentulous patients with highly atrophic mandibles. MATERIAL AND METHOD: This new device was used on 18 patients, between January 2000 and September 2004, who were then followed-up for at least 36 months. Mandibular atrophy was measured with a lateral cephalogram, then classified according to Atwood's modified classification. The studied criteria included the amplitude of distraction, its duration, the distractor's lingual tilt, the number and outcome of implants, and complications. RESULTS: The sex ratio was 17 female for one male patient. The mean patient age was 56 years (43 to 66 years). The mean distraction amplitude was 11.3mm (8 to 14 mm). The mean retention time was 186.8 days (37 to 309 days). The distractor's mean lingual tilt was 4.3 degrees (0 to 23 degrees ). Two mandibular fractures occurred 6 weeks after placing the Endo-Distractor. The first one was treated medically, and the second one required removing the Endo-Distractor and osteosynthesis. An average of four interforaminal implants were placed for a total of 24 Brånemark and 51 Straumann implants. Four implants were lost in a patient due to infection. All other implants were osseointegrated. No bone loss was detected at follow-up after functional loading. DISCUSSION: These results show that alveolar distraction is possible on severely atrophic mandibles. The quality of bone and gum reconstruction is satisfactory both for functional and esthetic results. Surgical difficulty and rate of complications were lower than with conventional distraction techniques.

Bilateral investigation of the temporomandibular joint. An autopsy study of edentulous individuals.

Investigations concerning normal and pathological anatomy of the temporomandibular joint (TMJ) have shown that pathological reactions such as deviations of the shape of the condyle, disc thinnings, disc perforations and osteoarthrotic changes are fairly common, particularly in the elderly population. Autopsy studies of the TMJ describe pathological findings respective to their location in different age groups, but most authors describe their findings for removed joints of one side only. The specific aim of this study was therefore to investigate the intra-individual relationships between the degenerative changes and deviations concerning the articular surfaces of the TMJs and the topographical distributions of these findings. In this investigation both joints of 22 edentulous individuals between 58 and 95 years of age were studied. Correlations were found between the right and left joints with respect to the anatomical location of the pathological findings.

Quantitative analysis of masseter and temporalis EMGs: a comparison of anterior guided versus balanced occlusal concepts in patients wearing complete dentures.

The lack of easily measurable, objective physiological activity parameters of the masseter and temporalis muscle during jaw movements in humans has led to the consideration to revise data of surface electromyographies (EMGs) by applying a computerized quantification method. The aim of this follow-up analysis was to get quantitative data out of EMG-records of an earlier study. These records were obtained with two different splints, splint 1 providing an anterior front-canine guidance and splint 2 providing bilateral balanced occlusion. Utilizing a computer aided integration method led to numeric results which statistically proves the prediction of the previous investigation. Applying the integration method, the EMG raw signal was transformed into area-values which enabled a statistical work up of the data. Wilcoxon test statistics shows a significant (P<0.05) lower muscle activity in patients wearing dentures providing anterior front-canine guidance compared to those with balanced occlusion. It is concluded that the neuromuscular activity of the elevator muscles is highly reproducible and that the neuromuscular function is similar in edentulous subjects to that found in people with natural teeth. Furthermore, the study statistically proves earlier visual data that all those subjects, whose muscle activities were observed with anterior guidance (splint 1) compared to bilateral balanced occlusion (splint 2) showed significantly lower values with regard to subjects wearing splint 2.

Masseter and temporalis surface electromyography in patients wearing complete dentures comparing anterior and posterior occlusal concepts--a pilot study.

The activity of jaw elevator muscles (masseter and anterior temporal muscle) was studied by surface electromyography in 17 patients wearing complete dentures with anterior-canine guidance. Baseline electromyography was recorded with the dentures and compared to recordings obtained with two different splints adapted to the upper denture, one providing anterior guidance leading to immediate disclusion of the posterior teeth during any jaw movement, the other providing posterior guidance buccally on the working side and lingually on the non-working side (bilaterally balanced occlusion). Recordings were obtained during a sequence of different jaw movements: postural position, maximal tooth contact in intercuspal position, protrusive movement of the mandible (under tooth contact) and during lateral excursions, also carried out under tooth contact. Muscle activity was not significantly different as recorded with dentures only versus with the splints providing anterior guidance. However, a significant increase in activity was observed with bilaterally balanced occlusion. The results of this study in edentulous people are similar to those found in patients with natural teeth.

Determination of pipamperone in human plasma by high performance liquid chromatography.

A sensitive and reproducible high performance liquid chromatographic method was developed for the determination of pipamperone (1'-[4-(4-fluorophenyl)-4-oxobutyl]-[1,4'-bipiperidine]-4'- carboxamide, Dipiperon, CAS 1893-33-0) in plasma samples. Pipamperone and its internal standard (piritramide or 1'-(3-cyano-3,3-diphenylpropyl)-[1,4'-bipiperidine]-4'-carbo xamide) were extracted from alkalinized plasma by liquid-liquid extraction and analysed on a reversed-phase (C18) column. In order to reduce analysis time, a gradient elution technique was applied. Chromatographic peaks were quantified by UV detection at two wavelengths. The method has a detection limit of 2 ng/ml, it proved to have good accuracy and precision, and was linear in the range of 2 to 400 ng/ml. The assay was extensively applied to study the pharmacokinetics in man after oral administration of the drug.

[Cephalometric analysis of Class III patients after surgery]. / Kephalometrische Analyse von Patienten aus dem progenen Formenkreis nach operativer Korrektur.

The University of Innsbruck, Department of Dentistry, analysed the cephalograms of 23 prognathic patients whose dysgnathia was corrected by an osteotomy of the mandible only. The obtained results were compared with an analysis of the respective models. Documentation was obtained prior to surgery, post-operatively and during follow-up examinations over a period of at least six years. Evaluation of the results focused on occlusion and the WITS-appraisal. Prior to surgery 21 patients presented with a macromandibulosis which in 50 percent of the cases was combined with a micro- or retromaxillosis. As a rule, there were also dento-alveolar compensations with retrusion of the lower front teeth and protrusion of the anterior maxillary teeth. Surgical results remained stable in 14 cases, three patients incurred a slight partial relapse while six patients had a significant relapse, though the original extend of the malocclusion with anterior crossbite reoccurred in two cases only. It was possible to prove the relationship between relapse and the existence of myofunctional disturbances. Consequently, safe long-term results may only be obtained by means of interdisciplinary planning and treatment.

[Effects of myofunctional disorders on occlusion following surgery for mesial bite]. / Die Auswirkungen myofunktioneller Störungen auf die Okklusion mach Progenieoperationen.

In a follow-up study of 24 patients with mesial bite operated on at the Department of Oral and Maxillofacial Surgery, University of Innsbruck Medical School, relations between the outcome of sagittal splitting and myofunctional disorders were investigated. Orofacial imbalances of variable extent were found to be present in 16 of the patients followed up. Effects of myofunctional factors on occlusal position, occlusion, overbite and overjet are reviewed. Five patients with particularly severe myofunctional disorders underwent detailed logopedic and myofunctional evaluation. Results are presented. As myofunctional factors may profoundly affect the late results of surgery, it is concluded that patients with myofunctional disorders should undergo adjuvant myofunctional rehabilitation before or at least after surgery in order to prevent relapses.

The mandibular condyles in the submentovertex projection--their morphology and topographical relationship to the foramina spinosa.

On conventional radiographs, the morphology and position of the condyles in an axial view are best seen in the submentovertex projection. The foramina spinosa, which are used by the middle meningeal arteries as passages and are clearly outlined in this view, serve as landmarks for a co-ordinate system that permits precise measurements of various angles and distances. One hundred and twenty-six submentovertex views were used for measuring the condyles. Results presented as means and standard deviations suggest condylar variables to be related to the function of the stomatognathic system. Practical applications include surgical, orthodontic or prosthetic manipulations of the mandible resulting in transverse or sagittal displacement of the condyles.