A study of 1000 malocclusions selected by the HLD (CalMod) Index

The purpose was to study the results of applying the HLD (CalMod) Index to a very large population of patients. The materials were the study models of 1000 cases that had already been measured and approved for treatment. Each model was remeasured and studied. The average age of the patients was 14.138 years of age; 55% were females and 45% were males. Fifty-six percent were approved on the basis of a score of 26 or more, and 44% were approved as one of the exceptions in the index. Fifty-eight percent of the patients were Class I, 35% were Class II, and 7% were Class III. Surprisingly, 26% of all the approvals (19% adjusted for overlap) were for overjets greater than 9 mm. Reverse overjets occurred at the rate of 2% of approvals. Deep impinging overbites with tissue destruction comprised 12% of all approvals and crossbites of individual anterior teeth with tissue destruction 4%. Only 4 cleft palate cases were recorded, as they do not routinely enter the system through the index route. No traumatic deviations were found. The HLD (CalMod) Index has been field tested under a very heavy load. This study demonstrated that it selects a very wide range of malocclusions.