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Reduction mentoplasty.

A reduction in the projection of the chin can balance a profile, particularly following a rhinoplasty. It is important, however, that dental and facial bone relationships first be assessed in order to rule out the existence of complicating conditions. This examination may or may not include radiologic studies or dental models. The surgery can be performed under local anesthesia. A minimum of 2.5 to 3.0 mm of bone must be resected in order to effect change.

Adolescent↗

Maxillary distraction: aesthetic and functional benefits in cleft lip-palate and prognathic patients during mixed dentition.

In the last few years, distraction techniques have been used successfully to correct the hypoplastic human mandible. In patients with cleft lip and palate, normal growth of the maxilla may be impaired by early cleft repair, and many of them do not respond to orthodontic procedures alone. Maxillary distraction is an alternative technique to correct maxillary hypoplasia during mixed dentition. In the last 3 years, the procedure was performed in 38 patients aged between 6 and 12 years; 18 patients had unilateral cleft lip and palate, 9 patients had bilateral cleft lip and palate, 7 patients had unilateral cleft palate, 2 patients had prognathism, and 2 patients had nasomaxillary dysplasia. Photographs, posteroanterior and lateral cephalograms, and dental models are obtained preoperatively (as well as an orthopantomogram) to locate the tooth buds. A subperiosteal dissection is performed exposing the anterior and lateral aspects of the maxilla, and an incomplete horizontal osteotomy is done above the tooth buds. Using a facial mask and an intraoral fixed appliance system as an anchorage, we initiate on the fifth postoperative day the application of distraction forces. Maxillary advancement between 4 and 12 mm is achieved during 3 to 4 weeks, and a satisfactory class I or II molar relationship is also obtained. A combination of forward and downward distraction forces can be used to achieve simultaneous advancement and elongation of the hypoplasic maxilla. The aesthetic results are excellent, and the nasolabial angle is increased, including a more anterior projection of the upper lip. Nasal breathing is improved as well as the air flow and patency of the nasal airway. Velopharyngeal function remains unchanged after the procedure. The follow-up in this series varied from 6 months to 3 years. No relapses have been observed.

Child↗

Early cleft lip repair in children with unilateral complete cleft lip and palate: a case against primary alveolar repair.

All children with complete unilateral cleft lip and palate will develop some degree of malocclusion regardless whether the alveolar cleft is repaired primarily or bone grafting is deferred. To evaluate the impact of early gingivoperiosteoplasty on occlusal relationships, dental models were obtained in 5-year-old patients who underwent early cleft lip and palate repair with primary boneless bone grafting (Skoog's method) (56 children) and without alveolar intervention (51 children). The Goslon's occlusion grading system was applied to evaluate occlusal relationships in both groups. Patients with early surgical intervention to repair alveolar cleft demonstrated poor occlusal relationship with the Goslon score 4 and 5, which will likely need an orthognathic corrective procedure (50% vs. 19.6% in patients without early primary dissection of the alveolar process). Results reaffirm that an inclusion of the alveolar process into the early primary lip repair adds to the severity of occlusal maldevelopment.

Alveolar Process↗

Does hard insertion and space improve shock absorption ability of mouthguard?

Mouthguards are expected to reduce sports-related orofacial injuries. Numerous studies have been conduced to improve the shock absorption ability of mouthguards using air cells, sorbothane, metal wire, or hard material insertion. Most of these were shown to be effective; however, the result of each study has not been applied to clinical use. The aim of this study was to develop mouthguards that have sufficient prevention ability and ease of clinical application with focus on a hard insertion and space. Ethylene vinyl acetate (EVA) mouthguard blank used was Drufosoft and the acrylic resin was Biolon (Dreve-Dentamid GMBH, Unna, Germany). Three types of mouthguard samples tested were constructed by means of a Dreve Drufomat (Type SO, Dreve-Dentamid) air pressure machine: the first was a conventional laminated type of EVA mouthguard material; the second was a three layer type with acrylic resin inner layer (hard-insertion); the third was the same as the second but with space that does not come into contact with tooth surfaces (hard + space). As a control, without any mouthguard condition (NOMG) was measured. A pendulum type impact testing machine with interchangeable impact object (steel ball and baseball) and dental study model (D17FE-NC.7PS, Nissin, Tokyo, Japan) with the strain gages (KFG-1-120-D171-11N30C2: Kyowa, Tokyo, Japan) applied to teeth and the accelerometer to the dentition (AS-A YG-2768 100G, Kyowa) were used to measure transmitted forces. Statistical analysis (anova, P < 0.01) showed significant differences among four conditions of NOMG and three different mouthguards in both objects and sensor. About acceleration: in a steel ball which was a harder impact object, shock absorption ability of about 40% was shown with conventional EVA and hard-insertion and about 50% with hard + space. In a baseball that was softer compared with steel ball, a decrease rate is smaller, reduction (EVA = approximately 4%, hard-insertion = approximately 12%, hard + space = approximately 25%) was admitted in the similar order. A significant difference was found with all the combinations except for between EVA and hard-insertion with steel ball (Tukey test). About distortion: both buccal and lingual, distortions had become small in order of EVA, hard-insertion, and hard + space, too. The decrease rate is larger than acceleration, EVA = approximately 47%, hard-insertion = 80% or more, and hard +space = approximately 98%, in steel ball. EVA = approximately 30%, hard-insertion = approximately 75%, and hard + space = approximately 98% in baseball. And a significant difference was found with all the combinations (Tukey test). Especially, hard + space has decreased the distortion of teeth up to several percentages. Acceleration of the maxilla and distortions of the tooth became significantly smaller when wearing any type of mouthguard, in both impact objects. But the effect of mouthguard was clearer in the distortion of the tooth and with steel ball. Considering the differences of mouthguards, the hard-insertion and the hard + space had significantly greater buffer capacity than conventional EVA. Furthermore, hard + space shows quite high shock absorption ability in the tooth distortion. Namely, hard + space has decreased the distortion of teeth up to several percentages in both impact objects.

Acceleration↗

Tramadol: does it have a role in emergency medicine?

Tramadol is a synthetic analgesic new to the Australasian market where its use is rapidly increasing. It is used extensively overseas, particularly in Europe where it has been popular since its introduction in Germany in the late 1970s. Tramadol has a dual mechanism of action: weak mu opioid receptor agonist and a reuptake inhibitor of serotonin and noradrenaline. Thus, it has distinct advantages and disadvantages compared to other available analgesics. Its use is advocated in a variety of acute and chronic pain states as well as some non-analgesic applications. The use of tramadol in an emergency setting is not well studied, with most published trials assessing its efficacy and tolerability in postoperative or dental models. This literature review concludes that tramadol does not offer any particular benefits over existing analgesics for the majority of emergency pain relief situations.

Abdominal Pain↗

Segregation analysis of mandibular prognathism in Libya.

The etiology of mandibular prognathism has been attributed to various genetic inheritance patterns and some environmental factors. The variation in inheritance patterns can be partly due to the use of different statistical approaches in the respective studies. The objective of this study was to investigate the role of genetic influences in the etiology of this trait. We performed segregation analysis on 37 families of patients currently being treated for mandibular prognathism. Mandibular prognathism was treated as a qualitative trait, with cephalometric radiographs, dental models, and photographs used to verify diagnosis. Segregation analysis of a prognathic mandible in the entire dataset supported a transmissible Mendelian major effect, with a dominant mode of inheritance determined to be the most parsimonious.

Adult↗

The effect of birthweight on tooth-size variability in twins.

Studies indicate that low birthweight (LBW) children display reduced deciduous tooth size but there is little information about permanent tooth size. It has also been shown that dental fluctuating asymmetry (FA) increases in response to various environmental influences, but the relationship between birthweight and FA remains unclear. The aim of this study was to compare tooth size and asymmetry, according to birthweight, in the deciduous and permanent dentitions of a sample of Australian twins. The study sample comprised 436 twins, classified into 2 groups: normal birthweight (NBW > 2500 g) and low birthweight (LBW < or = 2500 g). For each individual it was generally possible to measure maximum mesiodistal crown diameters of both deciduous and permanent central incisors from serial dental models. Correlations were calculated between tooth-size variables and birthweight; subsequently comparisons of tooth size and FA were made between the LBW and NBW samples using Student's t tests. Small positive correlations (around .1) were noted between birthweight and tooth-size variables. There was no evidence of tooth-size reduction in the LBW male sample, but the LBW females displayed tooth-size reduction of approximately 2-3% for both deciduous and permanent incisors, compared to the NBW females. There was no evidence of increased FA in the LBW individuals of either sex. These findings indicate that developing teeth are generally well-protected from developmental disturbances during prenatal and perinatal periods. Further research is needed to clarify the biological basis of an apparently true but weak association between tooth size and birthweight.

Birth Weight↗

The Goslon yardstick applied to a consecutive series of patients with unilateral clefts of the lip and palate.

First described in 1987, the Goslon yardstick has been used since as a reliable and reproducible means of measuring dental arch relationships and, therefore, the quality of facial growth. The dental study models of a group of 32 consecutively treated patients with unilateral clefts of lip and palate, from the Frenchay Hospital, Bristol, U.K., were analyzed using the Goslon yardstick. More than 50% of the sample were in the unfavorable Goslon groups IV and V. Because of these results, we at Frenchay Hospital now base our related surgical procedures on the early vomerine closure of the anterior hard palate without nasal or alveolar repair at 3 months, followed by primary hard and soft palate closure at 6 months.

Age Factors↗

Laboratory communication for esthetic success.

There is no single or simple answer for effective communication between laboratory technician and clinical dentist. Doing the lab work oneself or having an in-house technician may be a distinct advantage to some albeit labor- and perhaps cost-intensive. If the goal of the practicing dentist is to aspire to excellence, it is incumbent upon him or her to produce restorations that fit the teeth well, are shaded correctly and, when indicated, are the same color as the surrounding teeth. Effective communication with the laboratory is critical if any degree of success is desired.

Color↗

Assessing the quality of clinical procedures and technical standards of dental laboratories in fixed partial denture therapy.

PURPOSE: This study was conducted to assess the quality of impressions and tooth preparations sent to dental laboratories in Jordan and to determine the technical capabilities of these laboratories to construct fixed partial dentures. MATERIALS AND METHODS: A sample of 136 impressions and stone casts were examined for clinical errors in 35 laboratories that construct fixed partial dentures. They were sorted into unusable, unsatisfactory, acceptable, or satisfactory categories. The type of impression material and tray, opposing arch impressions, and occlusal records were noted. Instructions to technicians were assessed for completeness and clarity. Information regarding laboratory staff and equipment were collected. RESULTS: Half of the specimens inspected were categorized as unusable or unsatisfactory; these were found in commercial laboratories. They showed at least one clinical error such as drags or indefinite finishing lines in impressions and inadequate reduction, undercuts, or obvious taper on stone casts. Alginate impression material was used for 65% of the cases. Only 27% of specimens were accompanied with instructions; of these 22% were graded poor. No occlusal records were available with 54% of the specimens and no articulators were used except in dental school laboratories. The dental schools and some commercial laboratories had the best staff and equipment and were more capable of fabricating fixed partial dentures than those of the Ministry of Health and the Royal Med cal Services. CONCLUSION: The quality of abutment preparation and impressions were unsatisfactory or unusable in 50% of cases. Of the 37 available instructions 8 were not clear. The dental schools and some commercial laboratories were technically capable of producing good quality fixed partial dentures.

Dental Abutments↗

[Comparison of closing T loop technique and sliding technique using preadjusted appliance].

OBJECTIVE: To compare the difference between closing T loop technique and sliding technique. In anchorage demand and treatment outcome. METHODS: Sixteen first premolar extraction cases were chosen and divided into two groups for prospective paired t-test. They were treated by one author using 0.022" x 0.028" preadjusted appliances. T loops were fabricated using 0.018" x 0.025" s.s. wire. Chinese NiTi coil springs and 0.019" x 0.025" s.s. arch wire were employed in sliding technique group. Treatment materials, steps and appliance design in both groups were standardized. Measurements of dental model and cephalogram were taken. RESULTS: In closing T loop technique group and sliding technique group, the ratio of anterior teeth movement was 0.55 and 0.53 respectively. The difference was not significant (P > 0.05). L1MP angle decreased by 5.7 degrees and 3.1 degrees respectively during treatment (P < 0.05). CONCLUSION: Demand on anchorage was not significantly different between two groups. Sliding technique was more favorable in maintaining anterior teeth inclination.

Adolescent↗

[Prognosis of utility of modified supracrestal fiberotomy and contact point reproximation in the treatment of anterior segment crowding].

OBJECTIVE: The aim of this study was to evaluate quantitatively the effectiveness and feasibility of the modified supracrestal fiberotomy (MSF) and the contact point reproximation (CPR) in decreasing the relapse of anterior segments rotating and/or crowding after orthodontic treatment. METHODS: A total of 129 patients with crowding and/or rotated anterior teeth were selected for this study, and the average age was 13.07 years (54 males, 75 females). The modified supracrestal fiberotomy was performed on the anterior segments of patients in the experimental group (48 cases). After the anterior teeth were aligned, 23 of the 48 cases received a further treatment of the contact point reproximation on the anterior segments (the subgroup of MSF + CPR), and the other 25 subjects did not receive this treatment (the subgroup of MSF). The control group consisted of 81 cases. All cases wore Hawley retainers for 1.8 to 2.3 years, and all the patients were revisited 2.4 years postretention. The maxillary and mandibular dental models of all the patients were taken before treatment (T1), at the end of the treatment (T2) and 2.4 years postretention (T3). RESULTS: The relapse rate in the experimental group [(T3-T2)/T1 x 100%] was 21.6%, lower than that in the control group (P < 0.001). The relapse rate of mandible in the subgroup of MSF + CPR was 6.56% lower than that of the subgroup of MSF (P < 0.05). But the relapse rate of maxillary in the subgroups of MSF + CPR was similar as that of the subgroup of MSF (P > 0.05). CONCLUSION: The modified supracrestal fiberotomy can effectively alleviate relapse after orthodontic treatment of the crowding and/or rotation of anterior teeth. The treatment combining MSF and CPR can help maintain the stability of post-retention of mandibular anterior teeth.

Adolescent↗

Infection control in fixed prosthodontics.

The breadth and depth of our knowledge of infection control continues to increase in dramatic proportions. The literature is already massive and there is nothing to suggest an abatement of this situation. In truth, we can expect the very opposite; an escalation in attention at every level of concern, from the effectiveness of the chemical agents as actually used in the dental environment, to our methods of delivery, as well as the effects on the materials, equipment, and even the personnel in the dental setting. This trend undoubtedly will continue as our understanding of disease processes and the mechanisms of disease transmission increases. This will, in part, directly impact the scope and direction of future study of infection control practices in dentistry.

American Dental Association↗