Clinical review of patients with fixed bridges (1)

This report comprises the first part of an investigation into the methodology of clinical examinations of patients with bridges. The complete study is concerned with the following problems.

• 1 To what extent do deviations occur between observers in the independent recording of factors of interest in the re-examination of patients with fixed bridges?
• 2 Are the deviations observed systematic?
• 3 Does a cumulative and simultaneous examination lead to less deviating results?
• 4 Are there any characteristic differences between observers with a greater or lesser degree of clinical experience?

     

Location of probe tip in bleeding and non-bleeding pockets with minimal gingival inflammation

Abstract In the present study the location of the probe tip was studied on human teeth scheduled for extraction for periodontal reasons. Prior to extraction all teeth were subjected to initial treatment consisting of plaque control and removal of supra- and subgingival deposits. Results showed that:

• 1 ) 43% of the pockets examined were still bleeding on probing after treatment
• 2 ) bleeding pockets were deeper than non-bleeding pockets
• 3 ) in non-bleeding pockets the probe tip was located more accurately at the attachment level than in bleeding pockets.

     

Sutureless gingival grafting

Abstract Suturing a gingival graft is often the most time-consuming stage of the grafting procedure, especially in regions of difficult access. Previously, it has been suggested that a combination of adhesive cellophane and cyanoacrylate may be used to immobilise the graft without suturing. The technique presented here attempts to simplify further sutureless grafting with the following modifications:

• – Bandage tape is used instead of adhesive cellophane.
• – The tape is not placed on the teeth but on the attached gingiva on either side of the graft site.
• – The use of cyanoacrylate is discarded.

The success of the procedure depends on complete haemostasis as any moisture will prevent the tape from adhering to the gingiva. Inherent advantages of sutureless grafting accomplished with the use of bandage tape are:

• – The graft lies flat on the recipient site and is kept under slight pressure by the tape.
• – Minimal blood clot is present between the graft and the recipient site.
• – The “wick” effect of the sutures is eliminated.
• – The chair side time is greatly reduced.
• – A shorter appointment and no sutures to remove imply less discomfort for the patient.

The technique is contraindicated should the patient present an allergic background to bandage tape.     

Reviewers' guide to evaluating manuscripts

• The abstract should clearly and concisely describe the study.
• Tips articles do not have abstracts.
• Clinical reports and technique articles should include a 1-paragraph, nonstructured abstract that summarizes the article and the presented procedure's advantages.
• Clinical Sciences/Research articles should include a structured abstract that contains the following sections:

• •Statement of

Abstract

• •None for Tips articles
• •Nonstructured for Clinical Report/Technique articles
• •Structured for Research/Clinical Science articles.
• •Includes Clinical Implications statement.

Material and methods

• •Materials cited with proper information (product, manufacturer, and manufacturer's city/state/country).
• •Methods explained fully, with attention to criteria for quantitative judgment and procedures

     

Quantification of marginal leakage of amalgam restorations in vitro

A method is described to quantify marginal leakage of amalgam restorations in vitro as a function of time. The method consists of the determination of the amount of nitrogen gas passing through the margins of the restoration at 2atm. pressure in 30min. The method described needs about sixteen specimen per experiment. The standard error is 20-30% of the mean leakage value and is independent of the type of condensation and the amalgam type. Two amalgams, the non-γ₂-Dispersalloy and the conventional, Amalcap was compared longitudinally over a period of 4 months. The results showed:

• 1 The marginal leakage of Dispersalloy decreased strongly with time; the time dependency of Amalcap was less pronounced.
• 2 That carefully condensed Amalcap showed significantly less marginal leakage than Dispersalloy.
• 3 Whereas the marginal leakage of Amalcap was dependant on the condensation procedure, the leakage of Dispersalloy did not depend strongly on it.

     

Histometric evaluation of periodontal bone loss in rats. I. The effect of marginal irritation, systemic irradiation and trauma from occlusion

The effect of marginal irritation, trauma from occlusion and total body X-irradiation on interradicular bone of Wistar rat molars, was studied after an experimental period of two weeks. Histologic findings and slatistical evaluation of histometric results indicate that:

• – the only single factor capable of reducing the height of interradicular bone was marginal irritation,
• – the only additional factor that was capable of increasing this reduction in height was total body X-irradiation,
• – marginal irritation, either alone or in combination with trauma from occlusion increased bone density in the submarginal area_t
• – total body X-irradiation inhibited the osteogenic reaction induced in the submarginal area by marginal irritation.
• – trauma from occlusion did not have any effect on the parameters measured.

     

Alterations in crevicular fluid flow during healing following gingival surgery

The relationship between gingival crevicular fluid flow and healing after gingival surgery, as assessed by biopsy, cytologic and microbial smears, was evaluated. Eighty-five periodontal pockets from the maxillary anterior and premolar teeth were studied in nine patients. Gingival fluid flow measurements, cytologic and microbial smears were taken weekly from each periodontal pocket for five weeks. The gingivectomy was performed at the first week and the tissue biopsied. Additional biopsies were also taken of selected areas on the fifth week. The results were analyzed to ascertain any correlation between gingival crevicular fluid flow and gingival inflammation during healing. The following conclusions can be drawn:

• 1 Quantity of gingival crevicular fluid, sulcular cytologic and microbial smears can be of value in assessing gingival status.
• 2 A direct relationship exists between the rate of crevicular fluid flow and healing following gingival surgery.
• 3 A healthy crevicular epithelium lining the gingival sulcus appears to function as a barrier, thereby retaining the gingival tissue fluid.

     

Autotransplantation of a maxillary third molar to replace a maxillary premolar with vertical root fracture

Aim To report the successful autotransplantation of a fully developed third molar that required nonsurgical and surgical interventions for tooth adaptation. Summary This case report describes the autotransplantation of a third molar with complete root development after the loss of a fractured premolar in a 47-year-old male. To allow better adaptation of the donor tooth, the buccal roots of the third molar were removed using a diamond bur and the canal entrances were filled. Recall examination 6 years after completion of root-canal treatment showed normal periodontal healing with absence of infection, ankylosis or progressive resorption. The transplantation of a third molar is seen as a promising method to replace a lost permanent tooth, and to restore aesthetics and function. Key learning points

• • Autotransplantation is a viable option for the treatment of a missing tooth or for replacement of traumatized tooth when there is a donor tooth available.
• • Fully developed third molars are potentially reliable candidates in the absence of other suitable donor teeth.

     

Clinical Judgement And Decision Making In Endodontics

Clinical judgement in endodontics consists of much more than diagnosis and treatment planning for the affected tooth. The issues involved in clinical judgement and decision making can be summarised by three questions:

• 1 Is endodontic treatment appropriate for the patient? Endodontic treatment should be undertaken only as part of an agreed, comprehensive treatment plan that takes into account patient concerns as well as objective clinical findings.
• 2 How difficult is the endodontic treatment? The difficulty of the case should be balanced with the skill and experience of the dentist, in deciding whether to manage the case in general practice or to refer the patient to an endodontist. The use of a standard form for assessing the difficulty of each endodontic case will aid in consistent, systematic assessment of patients. An example of such a form is provided.
• 3 What is the prognosis for the tooth? The outcome of endodontic treatment depends not only on the endodontic treatment but on other factors such as restorability and periodontal status. The prognosis will be compromised by procedural problems and by restorative and periodontal factors.

In all but routine cases, the steps involved in decision making may be more complex and less easily resolved than the practical clinical aspects of endodontic therapy.     

Ridge preservation in cases requiring tooth extraction during endodontic surgery: a case report

Aim To provide a treatment option to endodontists performing surgery that will enhance ridge preservation when tooth extraction is required. Summary A 47‐year‐old woman was referred to an endodontic practice for apical root‐end resection of tooth 22 because of refractory periradicular disease. Radiographic examination revealed a large periradicular lesion, 5 mm in diameter and a root‐end filling at the root apex. The treatment plan included exploratory surgery and apical root‐end resection. A vertical root fracture was diagnosed and the decision was made to extract the tooth. The socket was grafted with a cancellous bovine bone and covered with a resorbable collagen membrane. Follow‐up examination revealed favourable bone healing with formation of a new cortical plate and the preservation of soft tissue width and height in the aesthetic area. Key learning points

• • The principles of guided bone regeneration.
• • Preserving or reconstructing the extraction socket.
• • Enhances the ability to restore function and provide aesthetically pleasing restorations to patients without violating the predictability and function of the prostheses.

     

A two-year clinical study comparing the effect of dentifrices on selected dental materials

• 1 A two-year double-blind human clinical study has been conducted to determine the comparative effect of two commercially available dentifrices on selected dental materials.
• 2 Forty-three adult subjects were selected to participate. They received either acrylic resin or silicate restorations in their anterior teeth, or a full cast gold veneer crown with an acrylic surface.
• 3 The subjects were randomly assigned to either one of the two dentifrices and utilized the dentifrice in their normal manner at least 3 times per day.
• 4 The dental restorations were clinically evaluated in reference to their surface characteristics immediately after placement, and after 3, 6, 12 and 24 months' use of the dentifrices. The acrylic surfaces of the veneer crowns were also evaluated at these same time periods; however, in this case an in vivo tooth surface reflectance measurement technique was also utilized.
• 5 The results of this clinical study provide the following conclusion after 24 months use of the two dentifrices: There was no difference between the two dentifrices in that neither dentifrice produced any abnormal or unusual effect on the surface characteristics of either the acrylic or silicate anterior restorations, or the acrylic surfaces of the veneer crowns.

     

Statement of purpose and methods

The Journal of Evidence-Based Dental Practice has two primary goals:

• •To improve patient outcomes and health
• •To facilitate decision making that results in better patient outcomes, enhanced research planning, better products, and improved policy development.

     

Prevalence of juvenile periodontitis in Finland

Abstract The prevalence of juvenile periodontitis was studied in Finland, in an ethnic group representing a uniform Caucasoid population. The study population consisted of the 16–year-old subjects in the county of Uusimaa, population approximately 1,000,000. The screening study was based on the well-organized national dental care service which provides free dental care for all, up to the age of 17. Bitewing radiographs taken of all subjects at the age of 16 were used as the basic material for screening for juvenile periodontitis. Altogether 8,096 pairs of bitewing radiographs were available from the 16–year-old subjects born in 1960–61, representing 56 % of the total age group. The radiographs were examined by the author and 28 cases were singled out for thorough clinical and radiographic examination. The following criteria were set for juvenile periodontitis:

• – The patient must be in good general health
• – Radiographically detectable bone loss more than 2 mm must be demonstrated around more than one tooth
• – Local irritants must not be commensurate with the bone loss.

Eight cases among the 8,096 subjects fulfilled these criteria giving a prevalence of 0.1 %. With 95 % confidence this gives an estimate between 0.06 and 0.26 %.     

A roentgenographic study of clinically healthy and inflamed periodontal tissues in children

In an investigation of the effect of prolonged daily supervision of toothbrushing on Swedish schoolchildren (Koch and Lindhe, 1965; Lindhe and Koch, 1966) the incidence and severity of gingivitis in the experimental group were found to be substantially less than in the control group. It was therefore thought of interest to ascertain if there were roentgenographically detectable differences between the groups. The present investigation was carried out on 64 Swedish scoolchildren, randomly picked from the larger material taking part in the above mentioned investigation. Of these, 33 belonged to the supervised group and 31 to the group serving as a control. The criteria used for the diagnosis of periodontal disease in the roentgenograms were:

• 1 marginal tickening of the periodontal membrane.
• 2 defects of the margin of the alveolar crest.
• 3 increased distance between the cemento-enamel junction and the peak of the alveolar crest.

Roentgenographs of the upper and lower front teeth were obtained using a modified parallel technique. The roentgenographic interpretation was carried out as a blind test. No statistically significent differences between the two groups were found. Because of these findings, roentgenograms of the 14 cases who showed no signs of gingival inflammation and of the 10 cases who had the highest gingival scores were selected. These roentgenograms were re-examined simultaneously by two of the authors. As before, no statistically significant differences were found between the two groups.     

Application of an air-abrasive cutting apparatus in the pediatric dental field: Cutting using chitin-chitosan grains

Using an air-abrasive cutting apparatus, cavity preparation of dentin and artificially softened dentin was performed using alumina or chitinchitosan grains as cutting media. As a result of scanning electron microscopic observation, the following findings were obtained:

• 1.In cutting specimens that showed high values for Knoop hardness, alumina grains exhibited excellent cutting effects.
• 2.Regarding specimens after decalcification for each duration, the amount of cutting was significantly larger with alumina grains than with chitin-chitosan grains.
• 3.Regarding specimens cut using chitin-chitosan grains, the deepest cavity preparation was obtained in the specimens decalcified for 12 hours.
• 4.Healthy dentin was effectively cut by the ejection of alumina grains, whereas artificially softened dentin was effectively cut by the selective use of chitin-chitosan grains.
• 5.Adhesion of a large amount of chitin-chitosan grains in the wet dentin specimens was observed.
• 6.The amount of chitin-chitosan grain adhesion was the largest in the wet dentin specimens decalcified 12 or 24 hours.

     

Horizontal/oblique root fractures in the palatal root of maxillary molars with associated periodontal destruction: case reports

Aim To report two cases of palatal root fracture in maxillary molars that were successfully managed in the short term by root canal treatment and root amputation. Summary In the first case, a 48‐year‐old woman with bony destruction and a deep periodontal pocket on the palatal root of tooth 26 (FDI) underwent root canal treatment. Bleeding into the palatal canal and radiolucent lines over the root suggested a fracture. Further evidence was provided by an electronic apex locator. Subsequent surgery confirmed the presence of a horizontal root fracture and the fractured root was removed. In the second case, a 75‐year‐old woman presented with pain from the left posterior teeth. Clinical examination revealed an oblique root fracture of tooth 27 palatal roots with abscess formation and a deep periodontal pocket. Palatal root amputation and odontoplasty were performed. This was followed by root canal treatment. Both teeth were preserved in the short term and early healing of these two cases was uneventful. Key learning points

• ? Horizontal/oblique root fracture of the palatal root in molars is rare.
• ? A combination of periodontal and root canal treatment and palatal root amputation may allow short‐term preservation of functional teeth.

     

The occurrence of plaque and gingivitis and its relationship to tooth alignment within the dental arches

Abstract The aim of the present investigation was to evaluate whether and to what degree discrepancies in tooth alignment can influence plaque accumulation and gingival status, An intra-individual study was performed on 30 children with unilateral malposition of upper lateral incisors (15 children) and lower second premolars (15 children). Corresponding contralateral teeth were used as controls. The meanage was 14.4 years. The degree of malalignment in individual cases was assessed using a new malposition index (MPI). Plaque and gingival condition were assessed according to Silness & Löe (1964) and Löe & Silness (1963), respectively. The test and control areas were compared with regard to plaque accumulation and gingival status. Correlation analysis was performed to test the connection between these two parameters and tooth malalignment. The frequency of visible plaque (P1I 2+ 3) and gingival bleeding (GI 2 + 3) was generally higher for the test areas compared with the control areas. A comparison between the test and control areas showed the difference in gingival bleeding to be significant and of similar magnitude as regards upper laterals and lower second premolars. The difference in visible plaque was less marked but still significant. The correlation analysis did not show any connection between the degree of plaque accumulation or gingival inflammation and the degree of tooth malalignment. The differences found between normal and malaligned teeth thus showed a difnite trend, namely:

• – plaque and gingivitis were more widespread around malaligned upper lateral incisors and lower second premolars than around contralateral teeth well positioned within the dental arches.
• – the degree of malalignment was of secondary importance.

     

Apexogenesis after initial root canal treatment of an immature maxillary incisor – a case report

Aim To present a case where a traumatized, immature tooth still showed capacity for continued root development and apexogenesis after root canal treatment was initiated based on an inaccurate pulpal diagnosis. Summary Traumatic dental injuries may result in endodontic complications. Treatment strategies for traumatized, immature teeth should aim at preserving pulp vitality to ensure further root development and tooth maturation. A 9‐year‐old boy, who had suffered a concussion injury to the maxillary anterior teeth, was referred after endodontic treatment was initiated in tooth 21 one week earlier. The tooth had incomplete root length, thin dentinal walls and a wide open apex. The pulp chamber had been accessed, and the pulp canal instrumented to size 100. According to the referral, bleeding from the root made it difficult to fill the root canal with calcium hydroxide. No radiographic signs of apical breakdown were recorded. Based on radiographic and clinical findings, a conservative treatment approach was followed to allow continued root development. Follow‐up with radiographic examination every 3rd month was performed for 15 months. Continued root formation with apical closure was recorded. In the cervical area, a hard tissue barrier developed, which was sealed with white mineral trioxide aggregate (MTA). Bonded composite was used to seal the access cavity. At the final 2 years follow‐up, the tooth showed further root development and was free from symptoms. Key learning points

• ? Endodontic treatment of immature teeth may result in a poor long‐term prognosis.
• ? The pulp of immature teeth has a significant repair potential as long as infection is prevented.
• ? Treatment strategies of traumatized, immature permanent teeth should aim at preserving pulp vitality to secure further root development and tooth maturation.
• ? Radiographic interpretation of the periapical area of immature teeth may be confused by the un‐mineralized radiolucent zone surrounding the dental papilla.

     

Tooth mobility measurements following two methods of eliminating nonworking side occlusal interferences

Abstract The objective of this study was to compare tooth mobility following two methods of eliminating nonworking side interference (NWSI). The first method involved the complete elimination of any tooth contact on the NWS. The second method involved the reduction of the NWSI to a level which was harmonious with the occlusion on the working side. Thirty-three clinically healthy individuals having nonworking side interferences and no pathological signs of occlusal trauma, participated in the study. After 1 month of intensive training in oral hygiene, the volunteers were divided into three groups of 11 each. The first two groups were experimental and the third group received no occlusal adjustment to serve as a control. In the first group tooth mobility measurements and periapical x-ray films of teeth with nonworking interferences were taken. Occlusal interferences were then totally eliminated by selective tooth grinding. Two months later mobility and x-ray recordings of same teeth were repeated. In the second group the same procedure was performed, but nonworking side interferences were adjusted to harmonious contacts with occlusion on the working side. Tooth mobility was measured in hundredths of a millimeter, using the microperiodontometer designed by Mühlemann (1954). Data were subjected to statistical analysis and the following conclusions were drawn:

• 1 Tooth mobility was significantly (P < 0.001) reduced after complete elimination of nonworking side interferences, as well as after adjusting the nonworking side interferences to harmonious contacts with occlusion on the working side (P < 0.01).
• 2 The reduction in mobility was significantly (P < 0.001) greater when occlusal interferences were completely eliminated than when harmonious contacts were achieved.
• 3 There were no detectable radiographic changes, either in the interproximal alveolar bone level or periodontal ligament spaces, 2 months following occlusal adjustment.

     

Morphological changes in the zygomatic arch during growth

Morphometry of the zygomatic arch was obtained using 30 Indian dried skulls at each of Hellman's dental stages: IIA, IIIA, IIIB, IVA, and VA, for a total of 150 skulls 300 sides. The following conclusions were obtained.

• 1.Though both the height and length of the zygomatic arch increased at all stages from IIA to VA, the rate of increase of the height indicated a value larger than the length.
• 2.The zygomaticotemporal suture consisted of the vertical element from the upper margin to the center and the horizontal element from the lower side to the margo inferior during the IIA period. This suture changed to a gradual curve from the upper margin to the margo inferior with the movement of the center and the lower side to the rear during the VA period.
• 3.The degree of interdigitation of the zygomaticotemporal suture increased from the IIA period to the IIIA and IIIB to IVA.

These findings suggest that the form of the zygomatic arch and the zygomaticotemporal suture showed growth change adjusting to the functional change in mastication with growth.