Biomedical subjects

Yango Pohl

Publications and source records attributed to Yango Pohl.

12 recordsLinked to original sources

PubMed2006

Interrelation between endodontic status, pathologic cemental granules and periodontal ligament adhering to the root of extracted teeth.

OBJECTIVES: To evaluate if the endodontic status has influence on the adherence of periodontal ligament (PDL) to extracted teeth and if the presence of "pathologic granules" is correlated to the endodontic status and/or the amount of adhering PDL. STUDY DESIGN: Extracted teeth with different endodontic status and exhibiting no marginal periodontitis were histologically examined. RESULTS: Observation of pathologic granules was related to a nonvital endodontium and to acute peroperative inflammation. Pathologic granules and denudation of the extracted roots were significantly related. Acute peroperative inflammation and low extraction forces were related to denudation of the roots. Such relation was not found for endodontic status, tooth type, root-form, and age of patients. CONCLUSION: The existence of pathologic granules in unexposed cementum is strictly related to teeth with a nonvital endodontium. There is no effect of the endodontic status on the adherence of PDL when an acute inflammation is absent.

Adolescent↗

PubMed2006

Treatment of replacement resorption by intentional replantation, resection of the ankylosed sites, and Emdogain--results of a 6-year survey.

The present clinical study investigated the outcome of intentional replantation using resection of the ankylosed sites of the root, extraoral endodontic treatment using titanium posts and Emdogain for periodontal healing following trauma-related ankylosis. During an evaluation period of 6 years, 16 ankylosed teeth affected by replacement resorption were treated as described. Evaluation parameters before treatment and during the follow-up period included Periotest scores, percussion sound and periapical radiographs. All findings were compared to those of the adjacent teeth. In a second accident, one tooth was lost after 7 months and was excluded as a dropout. Ankylosis did not recur in seven replanted teeth, which were observed for an average of 52.3 months (range: 24-68 months). Ankylosis recurred in eight teeth after an average period of 12 months (range: 4-26 months). An infraocclusion, normal or only slightly reduced Periotest scores and normal percussion sound were preoperatively found in six of seven successfully replanted teeth, which corresponded to a relatively small area of ankylosis. The majority of the teeth showing recurrent ankylosis preoperatively presented with normal position, negative Periotest scores and a high percussion sound which corresponded to an extended area of ankylosis. Statistically significant relationship between preoperative findings and the treatment outcome (P = 0.031) have become apparent. The results indicate that the treatment of minor areas of ankylosis by intentional replantation, resection of the ankylosed sites and Emdogain appeared to prevent or delay the recurrence of ankylosis in 7 of 15 teeth.

Adolescent↗

PubMed2006

Dental squash injuries - a survey among players and coaches in Switzerland, Germany and France.

Squash belongs to sporting activities with medium risk of causing dental trauma. Because of high velocity, close body contact and the use of rackets the injury potential in squash has increased. The aim of this work was to conduct a comparative study between Switzerland, Germany and France on a number of issues: the frequency of dental and facial injuries in squash, athletes' habits of wearing mouthguards, as well as the general level of information about emergency measures after a dental trauma and the resulting consequences. Using a standardized questionnaire a total of 653 individuals, 600 squash players and their 53 coaches, were interviewed. In each of the three countries 200 players belonging to four different divisions (juniors, amateurs, semi-professionals and professionals) were surveyed. Of these 653 interviewees 133 (20.4%) have already observed a dental injury; 27 (4.5%) have experienced a dental trauma themselves. Less than half of all interviewed players and coaches (47.6%) were aware of the possibility of replanting avulsed teeth. Just 5.1% were familiar with the tooth rescue kit. Only one individual wore a mouthguard. The results show that the area of squash requires more information about prevention through sports associations, coaches and dentists.

Adolescent↗

PubMed2005

Results after replantation of avulsed permanent teeth. I. Endodontic considerations.

Following avulsion and replantation, teeth are at risk for infection and infection related resorption (IRR). Severe discolorations of tooth crowns and cervical root fractures are common. This study presents data on endodontic related complications of avulsed teeth replanted following an extraoral endodontic treatment. Periodontal aspects will be discussed in the second part of the present publication. Twenty-eight permanent teeth in 24 patients aged seven to 17 years were replanted after avulsion. All teeth could be evaluated. In all teeth extraoral endodontic treatment by retrograde insertion of ceramic or titanium posts was performed. Mean observation period was 31.2 months (median: 24.1 months). Nine teeth healed with a functional periodontal ligament (PDL) (functional healing, FH), 19 teeth exhibited replacement resorption (RR), which was succeeded by IRR in three teeth after observation periods of more than 14 months. Diagnosis was set to tunneling resorption (one case) and to cervical resorption preceded by complete RR (two cases). No early IRR was observed. All six teeth rescued in physiologic conditions (cell culture medium of tooth rescue box) exhibited FH. Discolorations of tooth crowns or other complications (cervical root fractures, fractures of posts) were not observed. No differences in the healing results of immature and mature teeth were observed which is in contrast to previous studies. This finding is explained with the different endodontic treatment protocols. Extraoral endodontic treatment by retrograde insertion of posts prevents early IRR and minimizes the overall incidence of IRR. The method does not negatively influence periodontal healing. As there are further advantages (no discoloration, no root fractures, patient not involved, less radiographs, less time consumption, less costs) the method is recommended in isolated teeth before replantation. Especially immature teeth profit from the prevention of complications.

Adolescent↗

PubMed2005

Results after replantation of avulsed permanent teeth. II. Periodontal healing and the role of physiologic storage and antiresorptive-regenerative therapy.

The status of the periodontal ligament (PDL) and of the pulp are decisive for the healing of avulsed and replanted teeth. A tooth rescue box was developed and distributed to offer optimal storage conditions for avulsed teeth. The therapy comprised extraoral endodontic treatment and applications of medicaments to enhance periodontal healing. In this long-term clinical study the healing results following avulsion and replantation were investigated. Twenty-eight permanent teeth in 24 patients were evaluated. The extraoral storage media and periods varied considerably. Soon after avulsion six teeth were stored in a cell culture medium (tooth rescue box Dentosafe) for 1-53 h; the PDL was defined as not compromised. Sixteen teeth were stored in a non-physiologic situation temporarily, the PDL was considered as compromised. Six teeth were stored in non-physiologic conditions for longer periods; the condition of the PDL was defined as hopeless. On 14 teeth antiresorptive-regenerative therapy (ART) with the local application of glucocorticoids and enamel matrix derivative and the systemic administration of doxycyclin was used. In all teeth extraoral endodontic treatment by retrograde insertion of posts was performed. The mean observation period was 31.2 months (+/-24.1; 5.1-100.2; median: 23.8). All six teeth rescued physiologically healed with a functional PDL (functional healing, FH) irrespective of the storage period. Of eight teeth with a compromised PDL on which ART was used, three teeth healed with a functional PDL. All other teeth showed replacement resorption, in three teeth additionally infection-related resorption was recorded. The predominant influence on the healing results was the immediate physiologic rescue of avulsed teeth (chi-square, P = 0.0001). The use of ART seemed to support FH (chi-square, P = 0.0547) in teeth with a compromised PDL. No other factors (maturity of roots, crown fractures, gender, age, antibiotics) were related to healing. In a linear regression analysis physiologic storage (P = 0.0013) and ART (P = 0.0421) were related to FH. For a good prognosis avulsed teeth should be stored immediately in a cell-compatible medium. Therefore the tooth rescue box should be distributed at places with higher risks of accidents, in families with children and in emergency facilities. The use of ART might have potential for enhancing the prognosis of teeth with a PDL that is compromised but not in a hopeless condition. Extraoral endodontic treatment reduces infection-related complications; this item was discussed in the first part of the publication.

Adolescent↗

PubMed2005

Results after replantation of avulsed permanent teeth. III. Tooth loss and survival analysis.

Avulsed permanent teeth were replanted following immediate extraoral endodontic treatment by insertion of posts from a retrograde direction. Some teeth were rescued in a physiologic environment (tissue culture medium contained in a tooth rescue box), and in some cases antiresorptive-regenerative therapy (ART) was used. The aim of the study was to identify variables that influence the incidence of tooth loss and the survival of avulsed and replanted permanent incisors. Twenty-eight permanent teeth in 24 patients aged 7-17 years were investigated. In all teeth extraoral endodontic treatment by retrograde insertion of posts was performed. All nine teeth with functional healing (FH) were in situ. Of the 19 teeth with non-FH, seven were removed to allow transplantations. Two teeth were removed due to severe infrapositions. One tooth was lost following a new trauma. No tooth was lost due to acute infections. In descriptive statistics the incidence of tooth loss was significantly related to healing (P = 0.0098, Fisher's exact test), to treatment planning, i.e. consecutive replantation of premolars and primary canines (P = 0.0001, Fisher's exact test) and to immediate physiologic rescue (P = 0.0394). ART was related to tooth loss when tested in teeth with a compromised periodontal ligament (P = 0.0389). No influence could be found for the parameters maturity, age and all other factors. In a regression analysis treatment planning was the only factor left which had a significant influence (P = 0.0002). The estimated mean survival time (Kaplan-Meier analysis) for all teeth was 57.3 months. The survival was significantly reduced (P = 0.0002, log rank test) when consecutive transplantations were intended and performed. No influence could be found for maturity, age and all other factors. The different findings to previous studies can be explained by the prevention of complications related to conventional endodontic treatment approaches. Statistics have to be carefully interpreted due to case preselection which is determined by the treatment guidelines and actual treatment options of the individual treating dentist.

Adolescent↗

PubMed2005

Level of information concerning dental injuries and their prevention in Swiss basketball--a survey among players and coaches.

Basketball carries a medium risk of dental injuries. Swiss data are not available in this respect. Using a standardized questionnaire 302 basketball players from 29 Swiss teams and their 29 coaches were interviewed. The questions focused on the frequency of dental accidents, their prevention and subsequent procedure. The participating 302 players came from three divisions: semi-professional players of National League A and B (102), amateurs of Regional League 2 and 3 (100) and young people of up to the age of 18 (100). The data were evaluated in relation to division, sex and team function. Of the 331 interviewed persons 102 had already seen a dental trauma in basketball and 55 had already had a dental trauma. Only four of the interviewed persons wore mouthguards. The awareness of the procedure following a dental trauma was unsatisfactory. The results of the survey show that significantly more information and education is required in Swiss basketball not only through sports associations but also through coaches and dentists.

Adolescent↗

PubMed2003

Extraoral endodontic treatment by retrograde insertion of posts: a long-term study on replanted and transplanted teeth.

OBJECTIVE: The aim of the study was to investigate the healing results of teeth replanted or transplanted in different indications and treated by extraoral root canal therapy. STUDY DESIGN: Extraoral root canal treatment was performed from a retrograde direction with posts made of ceramics or titanium. Preoperatively, the pulp status was classified as definitely infected (n = 47) or not infected/symptomless (n = 78), and the condition of the periodontal ligament (PDL) was classified as damaged (n = 50) or not damaged (n = 75) according to trauma type and extraoral storage. The healing after replantation or transplantation was diagnosed as functional, ankylosis, or infection depending on clinical and radiographic findings. RESULTS: In total, 125 teeth in 99 patients were replanted or transplanted. Mean observation period was 44.4 months. Teeth with a less damaged PDL in no case exhibited ankylosis/replacement resorption after a mean observation period of 53 months. Teeth without preoperative infection of the pulp in no case showed infection-related complications after a mean observation period of 30 months. Teeth classified as definitely infected before treatment had a high frequency of continuous periradicular bone and root resorption. CONCLUSIONS: The extraoral insertion of posts appeared to inflict no additional damage to the PDL that was clinically relevant. Infection-related complications were prevented. Teeth that were classified as definitely infected at the time of treatment had a low rate of healing and should undergo conventional root canal disinfection before this surgical procedure is applied.

Adolescent↗

PubMed2003

[Tooth transplantation].

Tooth transplantations provide the option of replacing lost or missing teeth in a biological fashion. On account of their high success rates and primarily in Scandinavian countries, they are a popular alternative to orthodontic or prosthetic treatment--particularly in case of children or young people losing teeth in accidents. Success of the treatment is ensured by corresponding diagnosis and good preoperative planning. Tissue-conserving transplant collection and the corresponding conditioning of the transplant bed are of decisive importance for the regeneration of the pulp and the periodontium. The success of the therapy is also influenced by the type and duration of splinting. Depending on the surgical technique and the transplanted tooth, the success rates are between 78% and 96%. The success criteria of a transplantation are defined clinically and radiologically. The diagnosis for transplantation is made from an orthodontic, endodontic, traumatologic, periodontologic and cardiologic perspective. The present article provides an overview of literature and shows current plantation techniques.

Dental Pulp Necrosis↗

PubMed2002

Treatment of replacement resorption with Emdogain--a prospective clinical study.

The present clinical study investigated the outcome of intentional replantation using Emdogain for periodontal healing following trauma-related ankylosis. Sixteen ankylosed teeth affected by replacement resorption were treated as follows: After tooth extraction, the root canal was obturated with a retrograde titanium post. Emdogain was applied to the root surface and into the extraction socket with subsequent replantation of the tooth. Evaluation parameters included horizontal and vertical Periotest scores, percussion sound and periapical radiographs. All findings were compared to those of the adjacent teeth. The mean follow-up period was 15 months (range 4-24 months). Eleven teeth showed no signs of recurrence of ankylosis: they were in full function and exhibited no pathological clinical findings. Four severely traumatized teeth demonstrated a recurrence of ankylosis after a mean period of 6 months, one tooth was lost in a second accident after 7 months. The estimated probability of 1 year without recurrence of ankylosis was P=0.66 (95% confidence interval [0.40; 0.94]). The mean survival time was 10.2 months (SD 1.1). The results indicate that treatment of replacement resorption following light to moderate trauma with replantation and Emdogain appears to prevent or delay recurrence of ankylosis in many cases.

Adolescent↗

PubMed2002

PCNA-expression of cementoblasts and fibroblasts on the root surface after extraoral rinsing for decontamination.

Periodontal cells capable of proliferation were studied immunohistochemically on extracted human teeth after 2-min irrigation with saline or ozonized water and marking of Proliferating Cell Nuclear Antigen (PCNA). All specimens expressed PCNA. The labelling index (LI), i.e. the number of positive cells compared to the total number of cells, was 6.6% after irrigation with saline and 7.8% after irrigation with ozone. There was no difference in number and distribution of PCNA-positive cells from the coronal to the apical thirds of the roots. Irrigation with ozonized water showed higher labelling indices in comparison with saline, but this could not be statistically substantiated (P = 0.24). Ozonized water, not being isotonic, had no negative effect on periodontal cells remaining on the tooth surface after irrigation for 2 min.

Cell Division↗

PubMed2002

Knowledge and prevention of dental trauma in team handball in Switzerland and Germany.

The aim of this work was to conduct a comparative study between Switzerland and Germany about the frequency of dental injuries in handball, athletes' habits of wearing mouthguard, as well as the general level of information about first emergency measures after a dental trauma and the resulting consequences for athletes and their coaches alike. For this, using interviews, seven handball teams each in two countries (Switzerland/Germany) belonging to the amateur and semiprofessional leagues were surveyed. A total of 112 individuals, 28 females and 84 males, were interviewed. Thirty-two of the 112 interviewees have once observed a dental injury; 12 have experienced a dental injury themselves. Only 10 individuals wore a mouthguard. The results show that the area of handball still requires more information and education.

Adult↗