Pekka Ylipaavalniemi

A comparative prospective clinical study of two single-tooth implants: A preliminary report of 102 implants

STATEMENT OF PROBLEM Treatment of tooth loss in the anterior maxilla can involve difficult functional, esthetic, and psychologic problems, especially in young patients with otherwise good dentition. PURPOSE The purpose of this study was to provide a preliminary comparative evaluation of two implants (ITI and Astra) in single-tooth restorations. MATERIAL AND METHODS This prospective study of 102 single-tooth replacements with 56 ITI and 46 Astra dental implants was performed in 82 patients at the Finnish Student Health Service Foundation. One Astra implant was lost before loading. The overall survival rate of the implants was 97.8% for Astra implants and 100% for the ITI system. After the initial healing period of at least 6 months, the remaining 101 implants (56 ITI, 45 Astra) were free of periimplant infection and revealed no detectable mobility. Radiographs did not reveal signs of periimplant radiolucencies. All 101 implants received single-tooth crowns. RESULTS Periimplant parameters and acceptable implant function were examined and demonstrated satisfactory results with preestablished clinical parameters and radiographs at 1 year. During the observation time the mean marginal bone loss was 0.13 mm with Astra implants and 0.11 mm with ITI implants. Subjectively all patients were satisfied with their single-tooth restorations supported by either ITI or Astra dental implants. CONCLUSION The favorable results of this short-term study support the application of the two implant systems for single-tooth restorations, especially in the anterior region of the maxilla.

Prophylactic use of phenoxymethylpenicillin and tinidazole in mandibular third molar surgery, a comparative placebo controlled clinical trial

A clinical double-blind placebo controlled trial was carried out in 136 patients to test the value of the prophylactic use of phenoxymethylpenicillin and tinidazole in mandibular third molar surgery. The three patient groups were uniform with regard to the background data such as age and weight of the patients and the clinical status of the operated tooth, as well as to the observations made at surgery. No statistically significant differences were found between the study groups in the parameters used for evaluation. The results indicate that neither penicillin nor tinidazole have more effect on postoperative complications following operative extraction of wisdom teeth, than placebo tablets.

Factors predisposing to postoperative complications related to wisdom tooth surgery among university students.

In a retrospective study among 550 Helsinki University students 20 to 30 years old, factors predisposing to postoperative complications from removal of lower jaw wisdom teeth were evaluated. Patient records and panoramic tomograms covering the period from 1990 to 1993 were examined; 50 patients (9.1%) had postoperative complications after removal of a wisdom tooth. The most common complications were alveolar osteitis (2.9%), postoperative infection (2.6%), postoperative bleeding (1.5%), and dysesthesia of the lower lip or tongue (1.1%). Factors associated with increased postoperative complications were mesiohorizontal position of the tooth, deep impaction of the tooth, and use of oral contraceptives. Before patients undergo surgery for removal of wisdom teeth, those who use oral contraceptives or have difficult tooth impactions should be informed about the increased possibility of postoperative complications.

Clinical follow-up study of third molar eruption from ages 20 to 26 years

The development of 412 upper and lower third molars was clinically followed up for 6 years in 120 students, starting at the age of 20 years. Clinical and radiographic examinations carried out at baseline and 6 years later showed that during the follow-up period almost half the third molars originally recorded as partially erupted had erupted. When the lower third molars were initially invisible, only 9% of them had erupted by age 26 years whereas 29% remained invisible. When third molars had been already erupted at baseline, only a few were extracted during the 6-year follow-up period. It was concluded that a certain proportion of third molars erupt relatively late, and therefore the need for surgical interventions may decrease with age during early adulthood.

A comparison of diclofenac with and without single-dose intravenous steroid to prevent postoperative pain after third molar removal

The efficacy of 40 mg of methylprednisolone given intravenously before operation in combination with orally administered rapid-release and sustained-release diclofenac preparations in preventing postoperative pain after third molar removal was studied. The administration of methylprednisolone and diclofenac resulted in greater pain relief than did administration of diclofenac alone.

Change in clinical status of third molars in adults during 12 years of observation

PURPOSE The aim of the study was to follow the clinical changes in third molar status during a 12-year period in patients aged 20 to 32 years. PATIENTS AND METHODS The study was based on a follow-up of 81 university students (32 men, 49 women). They were clinically examined and panoramic radiographs were taken at baseline (mean age, 20.7+/-0.5 years) and at the end of the study (mean age, 32.6+/-0.6 years). RESULTS The students had 285 unerupted, partially erupted, or fully erupted third molars at the beginning of the study, and 150 at the end. On final examination, 115 teeth were erupted. During the first 6 years from age 20 to 26, various clinical changes took place in the status of the third molars. In the second 6 years, until age 32, the two main changes were either removal or eruption. During the 12-year follow-up, 22% of third molars erupted, a few even after 26 years of age; the percentage of third molars removed was 42%. CONCLUSION Third molars undergo continuous clinical change at least up to the age of 32 years.

Third molars as an acute problem in Finnish university students

The study was carried out to determine the risk of acute disease of third molars in young adult patients. The subjects in this case-control study were 100 consecutive university students who complained of third molar problems when making an appointment. The third molars were mostly mandibular, partly erupted, and distoangularly oriented. Severity of discomfort and interference with daily activities were graded by the patients on average as 5.0 (SD +/- 2.7) and 3.6 (SD +/- 2.9), on a scale from 0 through 10. Distoangular lower third molars caused the most discomfort and interfered most with activities of patients. The risk of acute disease in patients with distoangularly oriented third molars was 3.6 times that in other patients. Bivariate analysis showed that if the follicle of a distoangular third molar were enlarged, the risk of acquiring acute disease was 44 times that in other patients. It was concluded that early removal of partially erupted and distoangularly oriented lower third molars is recommended, especially when they are associated with an enlarged follicle.

Effective Postoperative Pain Control by Preoperative Injection of Diclofenac

SummaryWe have treated ninety-five patients undergoing surgical removal of third molar with diclofenac or placebo, administered double-blind either pre- or postoperatively. Postoperative pain was recorded hourly for the first 8 h using a 100 mm visual analogue scale.Preoperative administration of diclofenac produced more effective pain relief than either postoperative administration or placebo.Since diclofenac has an inhibitory action on prostaglandin synthesis prophylactic intramuscular administration may have reduced the inflammatory process before synthesis of prostaglandins was activated.

Long-term evaluation of estimates of need for third molar removal

PURPOSE The aim of this study was to evaluate the estimates on need for third molar removals made at age 20 after 12 years. PATIENTS AND METHODS The series consisted of 81 university students followed from age 20 to 32 years. At baseline and at study end, these students were clinically examined, and panoramic radiographs were taken. At baseline in 1982, a qualified oral surgeon had made estimates on need for removal of third molars within 5 years; 75% of students needed removals. Actual treatment performed was evaluated after 12 years. A questionnaire served to determine symptoms related to third molars during the 12-year period. RESULTS During the follow-up, one or more third molars had been removed from 67% of the former students. A total of 155 third molar removals had been estimated, but by age 32 years the percentage actually removed was only 59%. Of the 79 third molars taken out at the Finnish Student Health Service, 77% were initially estimated to need a surgical procedure, but actually 66% were simply extracted. Most were removed at around age 27 years. According to the questionnaire, 67% of the students were asymptomatic in the third molar region during 12 years. CONCLUSION Because need for surgical removal decreases during early adulthood, routine prophylactic extraction of asymptomatic third molars in young adults cannot be recommended. Well-defined indications for prophylactic removals are needed.

Pain and temperature sensations related to local analgesia

Following the injection of local analgesic solutions at room temperature (21 degrees C) and at normal body temperature (37 degrees C), respectively, in the oral submucosal region, it was found that most of the subjects experienced the solutions as being of body temperature, regardless of whether the temperature of the solution was 37 degrees C or 21 degrees C. The duration of soft tissue anesthesia was not influenced by the temperature of the solutions. After the anesthetic effect had subsided, prilocaine 4% caused post-analgesic pain less frequently than did lidocaine 2% with adrenalin 12.5 mug/ml. Following injections with different mepivacaine solutions it was found that a low pH caused more frequent pain than a high pH, that the addition of a vasoconstrictor caused more frequent pain than a plain solution, and that there was a tendency for more frequent pain with increasing concentrations of the local anesthetic agent. In this study the addition of adrenalin was not found to prolong the period of soft tissue anesthesia.